阅读说明：本技术 发光装置及其制造方法 (Light emitting device and method for manufacturing the same ) 是由 黄逸儒 庄东霖 郑季豪 于 2021-06-10 设计创作，主要内容包括：本发明提供一种发光装置,包括成长基板、发光元件、第一导电凸块以及第二导电凸块。发光元件设置于成长基板上,包括第一型半导体层、第二型半导体层、发光层、欧姆接触层、第一导体层以及第二导体层。发光层与第二型半导体层由凹槽贯穿。欧姆接触层设置于第一型半导体层上且位于凹槽中。欧姆接触层与第一型半导体层电性连接。第一导电层设置于第一型半导体层上且位于凹槽中。第一导电层覆盖欧姆接触层。第二导电层设置于第二型半导体层上且与第二型半导体层电性连接。一种发光装置的制造方法亦被提出。(The invention provides a light-emitting device, which comprises a growth substrate, a light-emitting element, a first conductive bump and a second conductive bump. The light emitting element is arranged on the growth substrate and comprises a first type semiconductor layer, a second type semiconductor layer, a light emitting layer, an ohmic contact layer, a first conductor layer and a second conductor layer. The light emitting layer and the second type semiconductor layer are penetrated through by the groove. The ohmic contact layer is arranged on the first type semiconductor layer and is positioned in the groove. The ohmic contact layer is electrically connected with the first type semiconductor layer. The first conductive layer is arranged on the first type semiconductor layer and is positioned in the groove. The first conductive layer covers the ohmic contact layer. The second conductive layer is disposed on the second type semiconductor layer and electrically connected to the second type semiconductor layer. A method for manufacturing a light emitting device is also provided.)

1. A light emitting device comprising:

growing a substrate;

the light-emitting element is arranged on the growth substrate and comprises:

a first type semiconductor layer;

a second type semiconductor layer;

the light emitting layer is positioned between the first type semiconductor layer and the second type semiconductor layer, and the light emitting layer and the second type semiconductor layer are provided with grooves which penetrate through the light emitting layer and the second type semiconductor layer;

the ohmic contact layer is arranged on the first type semiconductor layer, is positioned in the groove and is electrically connected with the first type semiconductor layer;

the first conducting layer is arranged on the first type semiconductor layer and is positioned in the groove, covers the ohmic contact layer and is electrically connected with the ohmic contact layer; and

the second conducting layer is arranged on the second type semiconductor layer and is electrically connected with the second type semiconductor layer;

the first conductive bump is electrically connected with the first type semiconductor layer through the first conductive layer and the ohmic contact layer; and

and the second conductive bump is electrically connected with the second type semiconductor layer through the second conductive layer.

2. The light-emitting device according to claim 1, wherein the first conductive layer is directly electrically connected to the first-type semiconductor layer.

3. The light-emitting device according to claim 1, wherein the light-emitting element further comprises:

a first current conducting layer disposed on the first conductive layer, and electrically connected to the first type semiconductor layer through the first conductive layer and the ohmic contact layer; and

and the second current conduction layer is arranged on the second conductive layer and electrically connected with the second type semiconductor layer through the second conductive layer.

4. The light emitting device of claim 3, wherein the first conductive layer is located between the ohmic contact layer and the first current conducting layer.

5. The light emitting device of claim 1, wherein the material of the ohmic contact layer comprises a III-V compound.

6. The light-emitting device according to claim 1, wherein a lattice constant of the ohmic contact layer is mismatched with a lattice constant of the first-type semiconductor layer.

7. The light emitting apparatus of claim 1, further comprising:

an insulating layer stack disposed on the light emitting element, the insulating layer stack comprising:

a first insulating layer; and

the second insulating layer is arranged on the first insulating layer;

the first connecting layer is arranged on the first insulating layer and is electrically connected with the first type semiconductor layer through the first conducting layer; and

a second connection layer disposed on the first insulation layer and electrically connected to the second type semiconductor layer through the second conductive layer,

the second insulating layer covers the first connecting layer and the second connecting layer, and the first connecting layer is electrically isolated from the second connecting layer through the first insulating layer and the second insulating layer.

8. The light-emitting device according to claim 7, wherein the first conductive bump is electrically connected to the first conductive layer through the first connection layer, and the second conductive bump is electrically connected to the second conductive layer through the second connection layer.

9. The light-emitting device according to claim 7, further comprising a third connection layer which is electrically floating and is disposed on the first insulating layer, wherein the third connection layer is electrically isolated from the first connection layer or the second connection layer by the first insulating layer and the second insulating layer.

10. The light-emitting device according to claim 1, further comprising an undoped semiconductor layer between the growth substrate and the light-emitting element.

11. The light emitting device according to claim 1, wherein the ohmic contact layer comprises a plurality of openings and islands surrounding the plurality of openings, and the first conductive layer fills the plurality of openings to contact the first-type semiconductor layer.

12. The light emitting device of claim 1, wherein the ohmic contact layer comprises a roughened surface comprising a plurality of microstructures.

13. A light emitting device comprising:

growing a substrate;

the light-emitting element is arranged on the growth substrate and comprises:

a first type semiconductor layer;

a second type semiconductor layer;

the light emitting layer is positioned between the first type semiconductor layer and the second type semiconductor layer, and the light emitting layer and the second type semiconductor layer are provided with grooves which penetrate through the light emitting layer and the second type semiconductor layer;

the ohmic contact layer is arranged on the first type semiconductor layer, is positioned in the groove and is electrically connected with the first type semiconductor layer, and is provided with a plurality of finger parts;

the first conducting layer is arranged on the upper surface of the ohmic contact layer and positioned in the groove, and the first conducting layer is electrically connected with the ohmic contact layer; and

and the second conducting layer is arranged on the second type semiconductor layer and is electrically connected with the second type semiconductor layer.

14. The light emitting device of claim 13, wherein the fingers are located in the grooves with a spacing between the fingers and the second type semiconductor layer.

15. The light-emitting device according to claim 13, wherein the light-emitting element further comprises an insulating reflective layer disposed on the light-emitting layer, the second type semiconductor layer, and the second conductive layer, wherein the insulating reflective layer comprises a plurality of openings.

16. The light emitting apparatus of claim 15, further comprising:

the first current conducting layer is arranged on the first conducting layer and is electrically connected with the first type semiconductor layer through the first conducting layer and the ohmic contact layer; and

and the second current conducting layer is arranged on the insulating reflecting layer, and the insulating reflecting layer is electrically connected to the second conducting layer through the plurality of openings so as to be electrically connected with the second type semiconductor layer.

17. The light emitting apparatus of claim 16, further comprising:

an insulating layer stack disposed on the light emitting element, the insulating layer stack comprising:

a reflective layer; and

the insulating layer is arranged on the reflecting layer;

the first connecting layer is arranged on the reflecting layer and is electrically connected with the first type semiconductor layer through the first current conducting layer; and

a second connection layer disposed on the reflective layer and electrically connected to the second type semiconductor layer through the second current conduction layer,

wherein the insulating layer covers the first connection layer and the second connection layer.

18. A method of making a light emitting device, comprising:

providing a growth substrate;

forming an undoped semiconductor layer on the growth substrate;

forming a light emitting device on the undoped semiconductor layer, comprising:

forming a first type semiconductor layer on the undoped semiconductor layer;

forming a light emitting layer on the first type semiconductor layer;

forming a second type semiconductor layer on the light emitting layer;

performing a first etching process to pattern the light emitting layer and the second type semiconductor layer, wherein at least one first groove is formed in the light emitting layer and the second type semiconductor layer and exposes the first type semiconductor layer;

forming a sacrificial layer to cover the first type semiconductor layer, the light emitting layer and the second type semiconductor layer;

performing a second etching process to pattern the sacrificial layer, wherein at least one second groove is formed in the sacrificial layer, and the orthographic projection of the second groove on the growth substrate is located in the orthographic projection of the first groove on the growth substrate;

forming an ohmic contact layer in the second groove;

removing the sacrificial layer;

forming a first conductive layer on the ohmic contact layer and electrically connecting the ohmic contact layer; and

forming a second conductive layer on the second type semiconductor layer;

forming a first current conducting layer and electrically connected to the first conductive layer, and forming a second current conducting layer and electrically connected to the second conductive layer;

forming a first insulating layer on the light emitting element, wherein the first insulating layer is provided with a plurality of openings to expose the first current conducting layer and the second current conducting layer respectively;

forming a first connection layer, a second connection layer and a third connection layer on the first insulation layer, wherein the first connection layer and the second connection layer are respectively and correspondingly electrically connected to the first current conduction layer and the second current conduction layer through the plurality of openings, and the third connection layer is electrically floating;

forming a second insulating layer on the first insulating layer, the second insulating layer isolating the first connection layer, the second connection layer and the third connection layer, wherein the second insulating layer includes a plurality of openings; and

forming a first conductive bump and a second conductive bump, wherein the first conductive bump and the second conductive bump are electrically connected to the first connection layer and the second connection layer through the plurality of openings of the second insulating layer, respectively.

19. The method of claim 18, wherein the step of forming a light-emitting element further comprises:

forming an insulating reflective layer on the light emitting layer, the second type semiconductor layer and the second conductive layer,

wherein the second current conducting layer is electrically connected to the second conducting layer through the plurality of openings of the insulating reflective layer.

20. The method of claim 18, wherein the first groove has a first width and the second groove has a second width, the first width being greater than the second width.

Technical Field

The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly, to a light emitting device and a method of manufacturing the same.

Background

Generally, the light emitting diode includes vertical and flip-chip light emitting diodes. The light emitting diode applied to the flip chip type comprises a first type semiconductor layer, a light emitting layer, a second type semiconductor layer, a first metal layer, a second metal layer, a first insulating layer, a first current conducting layer, a second insulating layer, a first bonding layer and a second bonding layer. The first type semiconductor layer has a first portion and a second portion. The light emitting layer is disposed on the first portion of the first type semiconductor layer. The second part of the first type semiconductor layer extends outwards from the first part and protrudes out of the area of the light-emitting layer. The second type semiconductor layer is configured on the luminous layer. The first metal layer is disposed on the second portion of the first type semiconductor layer and electrically connected to the first type semiconductor layer. The second metal layer is disposed on the second type semiconductor layer and electrically connected to the second type semiconductor layer. The first insulating layer covers the first metal layer and the second metal layer and is provided with a plurality of through openings respectively exposing the first metal layer and the second metal layer. The first current conducting layer and the second current conducting layer are arranged on the first insulating layer and filled in the plurality of through openings of the first insulating layer so as to be electrically connected with the first metal layer and the second metal layer respectively. The second insulating layer covers the first current conduction layer and the second current conduction layer and is provided with a plurality of through openings which are respectively overlapped with the first current conduction layer and the second current conduction layer. The first bonding layer and the second bonding layer are arranged on the second insulating layer and filled into the plurality of through openings so as to be electrically connected with the first current conducting layer and the second current conducting layer respectively. The first bonding layer and the second bonding layer are used for eutectic bonding to an external circuit board. However, in the process of providing the first metal layer, the first metal layer is not easily in ohmic contact (ohmic contact) with the first type semiconductor layer, and thus the performance of the light emitting diode is affected.

Disclosure of Invention

The invention provides a light-emitting device and a manufacturing method thereof, which have good performance.

The invention provides a light-emitting device, which comprises a growth substrate, a light-emitting element, a first conductive bump and a second conductive bump. The light emitting element is disposed on the growth substrate. The light emitting element comprises a first type semiconductor layer, a second type semiconductor layer, a light emitting layer, an ohmic contact layer, a first conductive layer and a second conductive layer. The light emitting layer is located between the first type semiconductor layer and the second type semiconductor layer. The light emitting layer and the second type semiconductor layer have a groove penetrating the light emitting layer and the second type semiconductor layer. The ohmic contact layer is arranged on the first type semiconductor layer, is positioned in the groove and is electrically connected with the first type semiconductor layer. The first conductive layer is arranged on the first type semiconductor layer and is positioned in the groove. The first conductive layer covers the ohmic contact layer and is electrically connected with the ohmic contact layer. The second conductive layer is disposed on the second type semiconductor layer and electrically connected to the second type semiconductor layer. The first conductive bump is electrically connected with the first type semiconductor layer through the first conductive layer and the ohmic contact layer. The second conductive bump is electrically connected with the second type semiconductor layer through the second conductive layer.

In an embodiment of the invention, the first conductive layer is directly electrically connected to the first type semiconductor layer.

In an embodiment of the invention, the light emitting device further includes a first current conducting layer and a second current conducting layer. The first current conducting layer is arranged on the first conducting layer, and the first current conducting layer is electrically connected with the first type semiconductor layer through the first conducting layer and the ohmic contact layer. The second current conduction layer is disposed on the second conductive layer, and the second current conduction layer is electrically connected to the second type semiconductor layer through the second conductive layer.

In an embodiment of the invention, the first conductive layer is located between the ohmic contact layer and the first current conducting layer.

In an embodiment of the invention, a material of the ohmic contact layer includes a III-V compound.

In an embodiment of the invention, a lattice constant of the ohmic contact layer is mismatched with a lattice constant of the first type semiconductor layer.

In an embodiment of the invention, the light emitting device further includes an insulating layer stack, a first connection layer, and a second connection layer. The insulating layer is stacked on the light emitting element and comprises a first insulating layer and a second insulating layer. The second insulating layer is disposed on the first insulating layer. The first connection layer is disposed on the first insulating layer. The first connecting layer is electrically connected with the first type semiconductor layer through the first conducting layer. The second connection layer is arranged on the first insulation layer. The second connection layer is electrically connected with the second type semiconductor layer through the second conductive layer. The second insulating layer covers the first connection layer and the second connection layer. The first connecting layer is electrically isolated from the second connecting layer by the first insulating layer and the second insulating layer.

In an embodiment of the invention, the first conductive bump is electrically connected to the first conductive layer through the first connection layer. The second conductive bump is electrically connected with the second conductive layer through the second connection layer.

In an embodiment of the invention, the light emitting device further includes a third connection layer electrically floating and disposed on the first insulating layer. The third connecting layer is electrically isolated from the first connecting layer or the second connecting layer through the first insulating layer and the second insulating layer.

In an embodiment of the invention, the light emitting device further includes an undoped semiconductor layer. The undoped semiconductor layer is located between the growth substrate and the light-emitting element.

In an embodiment of the invention, the ohmic contact layer includes a plurality of openings and an island surrounding the plurality of openings. The first conductive layer fills the plurality of openings to contact the first type semiconductor layer.

In an embodiment of the invention, the ohmic contact layer includes a rough surface. The rough surface includes a plurality of microstructures.

The invention provides a light-emitting device, which comprises a growth substrate and a light-emitting element. The light emitting element is disposed on the growth substrate. The light emitting element comprises a first type semiconductor layer, a second type semiconductor layer, a light emitting layer, an ohmic contact layer, a first conductive layer and a second conductive layer. The light emitting layer is located between the first type semiconductor layer and the second type semiconductor layer. The light emitting layer and the second type semiconductor layer have a groove penetrating the light emitting layer and the second type semiconductor layer. The ohmic contact layer is arranged on the first type semiconductor layer, is positioned in the groove and is electrically connected with the first type semiconductor layer. The ohmic contact layer has a plurality of fingers. The first conductive layer is arranged on the upper surface of the ohmic contact layer and is positioned in the groove. The first conductive layer is electrically connected with the ohmic contact layer. The second conductive layer is disposed on the second type semiconductor layer and electrically connected to the second type semiconductor layer.

In an embodiment of the invention, the finger is located in the groove, and a space is formed between the finger and the second-type semiconductor layer.

In an embodiment of the invention, the light emitting device further includes an insulating reflective layer disposed on the light emitting layer, the second type semiconductor layer and the second conductive layer. The insulating reflective layer includes a plurality of openings.

In an embodiment of the invention, the light emitting device further includes a first current conducting layer and a second current conducting layer. The first current conducting layer is disposed on the first conducting layer. The first current conduction layer is electrically connected with the first type semiconductor layer through the first conductive layer and the ohmic contact layer. The second current conducting layer is disposed on the insulating reflective layer. The insulating reflecting layer is electrically connected to the second conductive layer through the plurality of openings so as to be electrically connected with the second type semiconductor layer.

In an embodiment of the invention, the light emitting device further includes an insulating layer stack, a first connection layer, and a second connection layer. The insulating layer is stacked on the light emitting element and comprises a reflecting layer and an insulating layer arranged on the reflecting layer. The first connecting layer is arranged on the reflecting layer. The first connecting layer is electrically connected with the first type semiconductor layer through the first current conduction layer. The second connecting layer is arranged on the reflecting layer. The second connection layer is electrically connected with the second type semiconductor layer through the second current conduction layer. The insulating layer covers the first connection layer and the second connection layer.

The invention relates to a manufacturing method of a light-emitting device, which comprises the following steps. A growth substrate is provided. Forming an undoped semiconductor layer on the growth substrate. And forming a light emitting element on the undoped semiconductor layer. The step of forming the light emitting element includes the following steps. A first type semiconductor layer is formed on the undoped semiconductor layer. And forming a light emitting layer on the first type semiconductor layer. Forming a second type semiconductor layer on the light emitting layer. A first etching process is performed to pattern the light emitting layer and the second type semiconductor layer. At least one first groove is formed in the light emitting layer and the second type semiconductor layer and exposes the first type semiconductor layer. A sacrificial layer is formed to cover the first type semiconductor layer, the light emitting layer and the second type semiconductor layer. A second etching process is performed to pattern the sacrificial layer. At least one second groove is formed in the sacrificial layer. The orthographic projection of the second groove on the growth substrate is positioned in the orthographic projection of the first groove on the growth substrate. And forming an ohmic contact layer in the second groove. The sacrificial layer is removed. And forming a first conductive layer on the ohmic contact layer and electrically connecting the ohmic contact layer. And forming a second conductive layer on the second type semiconductor layer. A first current conducting layer is formed and electrically connected to the first conducting layer. Forming a second current conducting layer and electrically connecting to the second conducting layer. A first insulating layer is formed on the light emitting device. The first insulating layer has a plurality of openings to expose the first current conducting layer and the second current conducting layer respectively. And forming a first connection layer, a second connection layer and a third connection layer on the first insulation layer. The first connection layer and the second connection layer are respectively and correspondingly electrically connected to the first current conduction layer and the second current conduction layer through the plurality of openings. The third connecting layer is electrically floating. A second insulating layer is formed on the first insulating layer. The second insulating layer isolates the first connection layer, the second connection layer and the third connection layer. The second insulating layer includes a plurality of openings. Forming a first conductive bump and a second conductive bump. The first conductive bump and the second conductive bump are electrically connected to the first connection layer and the second connection layer through the plurality of openings of the second insulating layer, respectively.

In an embodiment of the invention, the step of forming the light emitting device further includes forming an insulating reflective layer on the light emitting layer, the second type semiconductor layer and the second conductive layer. The second current conducting layer is electrically connected to the second conducting layer through the plurality of openings of the insulating reflective layer.

In an embodiment of the invention, the first groove has a first width. The second groove has a second width. The first width is greater than the second width.

In view of the above, in the light emitting diode according to the embodiment of the invention, since the ohmic contact layer is electrically connected to the first type semiconductor layer, and the first conductive layer contacts the ohmic contact layer, the first conductive layer made of the metal material and the ohmic contact layer of the epitaxial structure form a structure with low impedance and ohmic contact characteristics on the first type semiconductor layer. Thereby, the electrical property of the first type semiconductor layer can be improved. Thus, the light emitting device can have excellent performance and quality. In addition, the manufacturing process of the light-emitting device can be simple and cost-saving.

Drawings

Fig. 1 is a schematic top view of a light emitting device according to an embodiment of the invention.

Fig. 2A to 2N are schematic cross-sectional views of the light emitting device of fig. 1 along a sectional line U-U' in a manufacturing method.

Fig. 2F is a partially enlarged schematic view of the region R1 of fig. 2E.

Fig. 2H is a partially enlarged schematic view of the region R2 of fig. 2G.

Fig. 3A to 3D are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention.

Fig. 3B is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention.

Fig. 4A to 4C are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention.

Fig. 4A is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention.

Fig. 4B is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention.

Fig. 5A to 5B are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention.

Fig. 5A is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention.

Fig. 6A to 6F are schematic cross-sectional views illustrating a method for manufacturing a light-emitting device according to another embodiment of the invention.

Fig. 7A to 7C are schematic cross-sectional views illustrating a method of manufacturing a light emitting device according to still another embodiment of the invention.

1,1A,1B,1C,1D,1E light-emitting device

10 growth substrate

12 undoped semiconductor layer

100 light emitting element

110 first type semiconductor layer

110' layer of semiconductor material of a first type

120 luminescent layer

120' layer of luminescent material

130 second type semiconductor layer

130' a semiconductor material layer of a second type

140,140A,140B ohmic contact layer

140T upper surface

141 opening hole

142 island-like part

143 microstructure

151 first conductive layer

152 second conductive layer

161 first Current conducting layer

162 second current conducting layer

171 first connection layer

172 second connection layer

173 third connection layer

181 first conductive bump

182 the second conductive bump

190 conductive member

210 sacrificial layer

220 insulating layer stack

221 first insulating layer

222 second insulating layer

230 insulating reflective layer

FP finger part

R1, R2, R3, R4, R5, R6 regions

SP distance

W1 first Width

W2 second Width

W3, W4, W5 Width

O1, O2 grooves

O3, O4, O5, O6 and O7 openings

Section line of U-U

Detailed Description

Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the description to refer to the same or like parts.

Fig. 1 is a schematic top view of a light emitting device according to an embodiment of the invention. Fig. 2A to 2N are schematic cross-sectional views of the light emitting device of fig. 1 along a sectional line U-U' in a manufacturing method. For clarity and ease of illustration, several elements are omitted from fig. 1 and 2A-2N. Referring to fig. 1 and fig. 2N, in particular, the light emitting device 1 can be applied as a flip-chip light emitting diode. The light emitting device 1 includes a growth substrate 10, a light emitting device 100 disposed on the growth substrate 10, and a first conductive bump 181 and a second conductive bump 182 electrically connected to the light emitting device 100. The light emitting device 100 includes a first type semiconductor layer 110, a second type semiconductor layer 130, a light emitting layer 120 between the first type semiconductor layer 110 and the second type semiconductor layer 130, a first conductive layer 151, and a second conductive layer 152. The first conductive layer 151 is disposed on the first type semiconductor layer 110 and electrically connected to the first type semiconductor layer 110. The second conductive layer 152 is disposed on the second type semiconductor layer 130 and electrically connected to the second type semiconductor layer 130. The first conductive bump 181 is electrically connected to the first type semiconductor layer 110 through the first conductive layer 151. The second conductive bump 182 is electrically connected to the second type semiconductor layer 130 through the second conductive layer 152. In an embodiment of the invention, the light emitting device 1 further includes an ohmic contact layer 140 disposed on the first type semiconductor layer 110 and electrically connected to the first type semiconductor layer 110. The first conductive layer 151 is disposed on the ohmic contact layer 140 and electrically connected to the ohmic contact layer 140. Since the ohmic contact layer 140 is disposed between the first type semiconductor layer 110 and the first conductive layer 151, the problem that ohmic contact is not easily formed between the first conductive layer 151 made of a metal material and the first type semiconductor layer 110 can be solved. In addition, the ohmic contact layer 140 and the first conductive layer 151 may have low impedance (low resistance) and ohmic contact characteristics, so that the quality and performance of the light emitting device 1 may be improved.

Referring to fig. 1, a light emitting device 1 generally includes a growth substrate 110 and a light emitting unit. The light emitting unit includes, for example, a first type semiconductor layer 110, a light emitting layer 120, a second type semiconductor layer 130, an ohmic contact layer 140, a first conductor layer 151, and a second conductor layer 152 (not shown in fig. 1). The light-emitting device 1 further includes a first connection layer 171 and a second connection layer 172. The first connection layer 171 is electrically connected to the first conductive layer 151. The second connection layer 172 is electrically connected to the second conductive layer 152.

As can be seen from fig. 1, the first connection layer 171 and the second connection layer 172 may be disposed opposite to each other and separated from each other. The light emitting layer 120 and the second type semiconductor layer 130 may have a groove O1 penetrating the light emitting layer 120 and the second type semiconductor layer 130. The groove O1 may be a notch and extends into the first connection layer 171 or the second connection layer 172 in a top view. The groove O1 may be defined by the sidewalls of the light emitting layer 120 and the second type semiconductor layer 130, and isolated from the sidewalls of the first connection layer 171 or the second connection layer 172.

In some embodiments, the ohmic contact layer 140 is disposed in the groove O1 and is isolated from the sidewall of the groove O1 (i.e., the sidewall of the light emitting layer 120 and the second-type semiconductor layer 130). Specifically, the orthographic projection of the ohmic contact layer 140 on the growth substrate 110 is located in the orthographic projection of the groove O1 on the growth substrate 110. The ohmic contact layer 140 and the groove O1 have a spacing SP having a width W3. In some embodiments, width W3 is, for example, but not limited to, 1 micron to 30 microns.

As can be seen in fig. 1, portions of the ohmic contact layer 140 may extend along the groove O1. The extended portions of the ohmic contact layer 140 may be defined as fingers FP. The finger FP does not overlap the light emitting layer 120 and the second-type semiconductor layer 130. In some embodiments, the contour of the fingers FP is disposed around the light emitting layer 120 and the second-type semiconductor layer 130. In other embodiments, the ohmic contact layer 140 further includes a connection portion (not shown) for connecting the plurality of fingers FP, but not limited thereto.

As shown in fig. 1, the first conductive layer 151 conformally covers the ohmic contact layer 140. A portion of the first conductive layer 151 is disposed in the groove O1 and may extend along the groove O1. The first conductive layer 151 is disposed around the light emitting layer 120 and the second type semiconductor layer 130, but not limited thereto. In other embodiments, the first conductive layer 151 may partially overlap the ohmic contact layer 140.

In some embodiments, the first connection layer 171 may be electrically connected to the first conductive layer 151 and the ohmic contact layer 140. The second connection layer 172 can be electrically connected to the second conductive layer 152 (see fig. 2N). The first conductive bump 181 and the second conductive bump 182 are electrically connected to the first connection layer 171 and the second connection layer 172, respectively. Under the above arrangement, the first conductive bump 181 and the second conductive bump 182 can be respectively used as a positive electrode or a negative electrode of the light emitting device 1 and are electrically connected to an external circuit element. Therefore, the light emitting device 1 can be applied to a visible light emitting device, an ultraviolet light emitting device, or other suitable light emitting devices, but not limited thereto.

The manufacturing process of the light emitting device 1 will be briefly described below with an embodiment.

Referring first to fig. 2A, a growth substrate 10 is provided. The material of the growth substrate 170 is, for example, C-Plane, R-Plane or A-Plane Sapphire (Sapphire) or other transparent material. Further, a single crystal compound having a lattice constant close to that of the first-type semiconductor layer 110 is also suitable as a material for the growth substrate 10. In some embodiments, the material of the growth substrate further includes silicon carbide (SiC), silicon (Si), aluminum nitride (AlN), gallium nitride (GaN), or aluminum gallium nitride (AlGaN), or other suitable materials, but is not limited thereto.

In one embodiment, the undoped semiconductor layer 12 may be selectively formed on the growth substrate 10. The material of the undoped semiconductor layer 12 is, for example, undoped aluminum nitride (undoped) or aluminum gallium nitride (algan) or other suitable materials, but not limited thereto.

Next, a stack of light-emitting elements is formed on the undoped semiconductor layer 12. For example, the undoped semiconductor layer 12 is located between the growth substrate 10 and the light emitting device. The stacked layers of the light emitting device of the present embodiment, for example, include a first type semiconductor material layer 110 ', a light emitting material layer 120 ', and a second type semiconductor material layer 130 ' that are sequentially grown and stacked on the growth substrate 10. In other embodiments, the light emitting device 1 may not have the growth substrate 10 or the undoped semiconductor layer 12.

In some embodiments, the first type semiconductor material layer 110' is, for example, an N-type semiconductor layer, including an N-AlGaN based (N-AlGaN based) material or N-Al_yGaN base/n-Al_xGaN-based materials (x ≠ y), but not limited thereto. The second type semiconductor material layer 130' is, for example, a P-type semiconductor layer, including, but not limited to, a P-AlGaN based (P-AlGaN based) material or a P-AlGaN based/P-GaN based material.

In some embodiments, the luminescent material layer 120' may be a Quantum Well structure (QW). In other embodiments, the light emitting material layer 120' may be a Multiple Quantum Well structure (MQW), wherein the Multiple Quantum Well structure includes a plurality of Quantum Well layers (Well) and a plurality of Quantum Barrier layers (Barrier) alternately arranged in a repeating manner. Further, the constituent material of the light emitting material layer 120' includes a compound semiconductor composition capable of emitting a light beam having a peak wavelength falling in an emission wavelength range of 220nm to 300nm (middle ultraviolet light) or 300nm to 400nm (near ultraviolet light). The material of the luminescent material layer 120' includes Al_xGaN base/Al_yGaN-based material, and x ≦ y, but not limited thereto.

Under the above arrangement, the light emitting device of an embodiment of the invention is, for example, an ultraviolet light emitting diode.

Referring to fig. 2B, a first etching process is performed to pattern the light emitting material layer 120 'and the second type semiconductor material layer 130' to form the light emitting layer 120 and the second type semiconductor layer 130. The patterned light emitting layer 120 and the second type semiconductor layer 130 have the first groove O1 formed in the light emitting layer 120 and the second type semiconductor layer 130. The first recess O1 may expose the surface of the first-type semiconductor material layer 110' or the first-type semiconductor layer 110. In some embodiments, the sidewall of the first groove O1 may be a slope, but is not limited thereto. Then, an etching process is performed to pattern the first-type semiconductor material layer 110' to form the first-type semiconductor layer 110. The first type semiconductor layer 110 is located on a portion of the undoped semiconductor layer 12, and the portion of the undoped semiconductor layer 12 may be exposed. The light emitting layer 120 is on the first-type semiconductor layer 110, and the second-type semiconductor layer 130 is on the light emitting layer 120.

Referring to fig. 2C, a sacrificial layer 210 is formed to cover the first-type semiconductor layer 110, the light emitting layer 120 and the second-type semiconductor layer 130. In some embodiments, the sacrificial layer 210 may be disposed on the sidewalls of the light emitting layer 120 and the second type semiconductor layer 130 and cover the upper surface of the second type semiconductor layer 130. The material of the sacrificial layer 210 includes an organic material or an inorganic material, for example, the inorganic material may include silicon dioxide (SiO)₂) Alumina (Al)₂O₃) Or silicon nitride (SiN), but not limited thereto.

Then, a second etching process is performed to pattern the sacrificial layer 210. The patterned sacrificial layer 210 may form at least one second groove O2 in the sacrificial layer 210. The orthographic projection of the second groove O2 on the growth substrate 10 is located in the orthographic projection of the first groove O1 on the growth substrate 10. In some embodiments, the first groove O1 has a first width W1. The first width W1 may be defined as the maximum distance between opposing sidewalls of the first groove O1. The second groove O2 has a second width W2. The second width W2 may be defined as the maximum distance between opposing sidewalls of the second groove O2. The first width W1 is greater than the second width. In some embodiments, the first width W1 is, for example, 3 to 100 microns. The second width W2 is, for example, 1 to 100 micrometers, but not limited thereto.

Referring to fig. 2D, an ohmic contact layer 140 is formed in the second groove O2. In detail, the step of forming the ohmic contact layer 140 may include performing a heating process on the growth substrate 10, wherein the heating temperature ranges from 100 ℃ to 1500 ℃ to grow crystals on the surface of the first-type semiconductor layer 150 exposed by the sacrificial layer 210. In some embodiments, the heating process further includes doping silicon or tetravalent element (e.g., carbon) into the ohmic contact layer 140. The ohmic contact layer 140 is an epitaxial (epitaxial) structure layer, and the material thereof includes gallium nitride, gallium aluminum nitride, indium gallium nitride, and indium gallium aluminum nitride. In some embodiments, the material of the ohmic contact layer 140 includes a compound of a group III-V material, or the above-mentioned material doped with aluminum or indium element, but is not limited thereto. In addition, the ohmic contact layer 140 may be a semiconductor epitaxial layer doped with a high concentration element, for example, the ohmic contact layer 140 is doped with a high concentration silicon, and the concentration of the doped carriers is 1017cm-3 to 1020cm-3, but not limited thereto. In some embodiments, the ohmic contact layer 140 may have a single crystal structure (monocrystailine), an amorphous structure (amophorus) or a polycrystalline structure (polycrystailine), which is not limited in the present invention.

Please refer to fig. 2E and fig. 2F. Fig. 2F is a partially enlarged schematic view of the region R1 of fig. 2E. The sacrificial layer 210 is removed. After the step of removing the sacrificial layer 210, the ohmic contact layer 140 may be located in the first groove O1 and not contact the light emitting layer 120 and the second-type semiconductor layer 130. The ohmic contact layer 140 has a spacing SP from the sidewall of the first groove O1. The spacing SP has a width W3. In some embodiments, the width W3 is smaller than the first width W1, and the width of the spacing SP is, for example, 1 to 50 micrometers, but not limited thereto. Thus, the orthographic projection of the ohmic contact layer 140 on the growth substrate 10 partially overlaps the orthographic projection of the first type semiconductor layer 110 on the growth substrate 10, and a part of the surface of the first type semiconductor layer 110 can be exposed.

In some embodiments, the ohmic contact layer 140 may have a trapezoidal cross-sectional shape. The upper surface 140T of the ohmic contact layer 140 may be a flat surface, but is not limited thereto. In addition, the ohmic contact layer 140 disposed in the first groove O1 may be the finger FP, and disposed around the light emitting layer 120 and the second type semiconductor layer 130 or surrounding the light emitting layer 120 and the second type semiconductor layer 130, but not limited thereto. The finger FP has a spacing SP from the light emitting layer 120 or the second-type semiconductor layer 130.

Please refer to fig. 2G and fig. 2H. Fig. 2H is a partially enlarged schematic view of the region R2 of fig. 2G. A first conductive layer 151 is formed on the upper surface 140T of the ohmic contact layer 140. In some embodiments, the first conductive layer 151 is conformal with the ohmic contact layer 140, for example. For example, the first conductive layer 151 covers the ohmic contact layer 140, and an orthographic projection profile of the first conductive layer 151 on the growth substrate 10 is similar to an orthographic projection profile of the ohmic contact layer 140 on the growth substrate 10. The orthographic projection of the first conductive layer 151 on the growth substrate 10 may be outside the orthographic projection of the ohmic contact layer 140 on the growth substrate 10, but not limited thereto. In some embodiments, the orthographic projection of the first conductive layer 151 on the growth substrate 10 may be located within the orthographic projection of the ohmic contact layer 140 on the growth substrate 10.

As shown in fig. 2G and 2H, the first conductive layer 151 may completely cover the ohmic contact layer 140 and directly contact the first type semiconductor layer 110, such that the first conductive layer 151 may be directly electrically connected to the first type semiconductor layer 110. The orthographic projection of the first conductive layer 151 on the growth substrate 10 partially overlaps the orthographic projection of the first-type semiconductor layer 110 on the growth substrate 10. A portion of the surface of the first-type semiconductor layer 110 may be exposed. In addition, the first conductive layer 151 is isolated from the light emitting layer 120 and the second type semiconductor layer 130.

In some embodiments, the first conductive layer 151 is, for example, a single metal layer or a stack of multiple metal layers, but not limited thereto. The material of the first conductive layer 151 includes chromium (Cr), titanium (Ti), aluminum (Al), aluminum Alloy (Alloy Al), aluminum copper Alloy (Alloy Al/Cu), silver (Ag), nickel (Ni), palladium (Pd), platinum (Pt), gold (Au), or a combination thereof.

It is noted that the metal material is not easy to form an ohmic contact directly on the first-type semiconductor layer 110. In an embodiment of the present invention, the ohmic contact layer 140 and the first type semiconductor layer 110 are a heterostructure (heterostructure). The lattice constant of the ohmic contact layer 140 is mismatched with the lattice constant of the first-type semiconductor layer 110. Therefore, after the epitaxial structure of the ohmic contact layer 140 is formed on the surface of the first type semiconductor layer 110, the first conductive layer 151 of the metal material may be formed on the ohmic contact layer 140 to complete the process of disposing the ohmic contact structure on the first type semiconductor layer 110. Under the above configuration, the first conductive layer 151 and the ohmic contact layer 140 may form a structure having low resistance and ohmic contact characteristics on the first type semiconductor layer 110. Thereby, the electrical property of the first type semiconductor layer 110 can be improved. The light emitting device 1 can have excellent performance and quality. In addition, the manufacturing process of the light emitting device 1 can be simplified and the cost can be saved.

Referring to fig. 2I, a second conductive layer 152 is formed on the second type semiconductor 130. The second conductive layer 152 is electrically connected to the second type semiconductor 130. In some embodiments, the orthographic projection of the second conductive layer 152 on the growth substrate 10 is located within the orthographic projection of the second type semiconductor 130 on the growth substrate 10, but not limited thereto. In other embodiments, the profile of the second conductive layer 152 may be similar to or cut to be equal to the profile of the second type semiconductor 130.

In some embodiments, the second conductive layer 152 is made of a material and has a structure similar to the first conductive layer 151, and includes a stack of metals or metal alloys. In other embodiments, the material of the second conductive layer 152 further includes Indium Tin Oxide (ITO), zinc oxide (ZnO), aluminum zinc oxide (AlZnO), or gallium zinc oxide (GaZnO) or other suitable transparent conductive materials. Thus, the light emitting area of the light emitting device 100 can be increased. In addition, the second conductive layer 152 and the second type semiconductor layer 130 have characteristics of low impedance and ohmic contact.

In some embodiments, the thickness of the second conductive layer 152 is, for example, 0A to 500A, but not limited thereto. The thickness of the second conductive layer 152 may be smaller than that of the first conductive layer 151, but is not limited thereto.

Thus, the light-emitting element 100 is substantially completed. The fabrication of the light emitting device 1 will be continued below.

Referring to fig. 2J, a first current conduction layer 161 and a second current conduction layer 162 are then formed. The first current conducting layer 161 is formed on the first conductive layer 151 and electrically connected to the first conductive layer 151. First conductive layer 151 is located between ohmic contact layer 140 and first current conducting layer 161. The first current conducting layer 161 is electrically connected to the first type semiconductor layer 110 through the first conductive layer 151 and the ohmic contact layer 140. Second current conducting layer 162 is formed on second conductive layer 152 and is electrically connected to second conductive layer 152. The second current conducting layer 162 is electrically connected to the second type semiconductor layer 130 through the second conducting layer 152. In some embodiments, the orthographic projection of the first current conducting layer 161 on the growth substrate 10 overlaps the orthographic projection of the first conductive layer 151 on the growth substrate 10. The orthographic projection of the second current conducting layer 162 on the growth substrate 10 overlaps the orthographic projection of the second conducting layer 152 on the growth substrate 10. In some embodiments, the thickness of first current conducting layer 161 is greater than the thickness of first conductive layer 151, but not limited thereto. The thickness of second current conducting layer 162 is greater than the thickness of second conductive layer 152, but not limited thereto.

In some embodiments, the materials and structures of the first current conducting layer 161 and the second current conducting layer 162 are similar to those of the first conductive layer 151, and include a metal or a metal alloy stack, which is not described herein again. In another embodiment, first current conducting layer 161 and second current conducting layer 162 may also be formed in the same step of forming first conductive layer 151 and second conductive layer 152. In still other embodiments, the current conducting layer may not be provided and may be directly replaced by a conductive layer.

Referring to fig. 2K, an insulating layer stack 220 (shown in fig. 2M) is then formed on the light emitting device 100. The insulating layer stack 220 includes a first insulating layer 211 and a second insulating layer 212. The detailed description is as follows.

After the steps of forming the first current conducting layer 161 and the second current conducting layer 162, a first insulating layer 211 is formed on the light emitting device 100. Specifically, the first insulating layer 211 covers the undoped semiconductor layer 12, the first type semiconductor layer 110, the light emitting layer 120, the second type semiconductor layer 130, the ohmic contact layer 140, the first conductive layer 151, the second conductive layer 152, the first current conducting layer 161, and the second current conducting layer 162. The material of the first insulating layer 221 includes a single layer or multiple layers of insulating materials or a structure in which multiple layers of insulating materials having different refractive indexes are alternately stacked, wherein the stacked structure of the insulating materials having different refractive indexes includes, for example, silicon dioxide and titanium dioxide (SiO)₂/TiO₂) Stacked structure of (a) or silicon dioxide and tantalum pentoxide (SiO)₂/Ta₂O₅) The stacked structure of (1).

In some embodiments, the first insulating layer 221 may be a reflective layer. For example, the first insulating layer 221 may include a Distributed Bragg Reflector (DBR) layer in which a plurality of insulating layers having different refractive indexes are stacked on one another.

In an embodiment not shown, the first insulating layer 221 may include an upper insulating layer and a lower insulating layer and a bragg reflective layer between the upper insulating layer and the lower insulating layer. In the above embodiments, the material and thickness of the upper insulating layer and the lower insulating layer can be adjusted to the reflection wavelength range of the bragg reflector. Therefore, the Bragg reflection layer adopts the upper insulation layer and the lower insulation layer with the thickness varying, so that the Bragg reflection layer has a wider reflection wavelength range and is suitable for being applied to terminal products needing a light-emitting effect in a wide wavelength range. However, the above materials and the application of the light emitting device are only examples, and in practice, when the bragg reflective layer is made of other materials, the application can be adjusted according to the reflective wavelength range. Under the above arrangement, when the first insulating layer 221 is a reflective layer, the light beam emitted from the light-emitting layer 120 of the light-emitting unit 100 can be reflected toward the growth substrate 10 in a concentrated manner, so as to improve the light-emitting effect and the light-emitting efficiency of the light-emitting device 1.

As shown in fig. 2K, the first insulating layer 221 may be patterned to form a plurality of openings O3 and O4 in the first insulating layer 221. The opening O3 and the opening O4 expose the first current conducting layer 161 and the second current conducting layer 162, respectively.

Referring to fig. 2L, a first connection layer 171, a second connection layer 172, and a third connection layer 173 are formed on the first insulation layer 211. The materials of the first connection layer 171, the second connection layer 172, and the third connection layer 173 are similar to those of the first conductive layer 151, and thus are not described herein again. The first connection layer 171 is electrically connected to the first current conducting layer 161 through the opening O3. The first connection layer 171 is electrically connected to the first type semiconductor layer 110 through the first current conducting layer 161, the first conductive layer 151 and the ohmic contact layer 140. The second connection layer 172 is electrically connected to the second current conducting layer 162 through the opening O4. The second connection layer 172 is electrically connected to the second type semiconductor layer 130 through the second current conducting layer 162 and the second conducting layer 152. In some embodiments, the third current conducting layer 173 is not electrically connected to the light emitting device 100 but electrically floating disposed on the first insulating layer 221. Under the above configuration, the third current conducting layer 173 can be used as a testing pad for performing an electrical test on the light emitting device 1 during the manufacturing process.

Referring to fig. 2M, a second insulating layer 222 is then formed on the first insulating layer 221. The second insulating layer 222 covers the first, second, and third connection layers 171, 172, and 173. Thus, the insulating layer stack 220 including the first insulating layer 221 and the second insulating layer 222 may be used to isolate the first connection layer 171, the second connection layer 172, and the third connection layer 173. The second insulating layer 222 is disposed on the first insulating layer 221 (i.e., the reflective layer). The material of the second insulating layer 222 includes silicon dioxide (SiO)₂) Titanium dioxide (TiO)₂) Or other suitable material, but not limited thereto.

As shown in fig. 2M, the second insulating layer 222 may be patterned to have a plurality of openings O5 and O6. The opening O5 corresponds to overlap the first connection layer 171 and expose the first connection layer 171. The opening O6 correspondingly overlaps the second connection layer 172 and exposes the second connection layer 172.

Referring to fig. 2N, a first conductive bump 181 and a second conductive bump 182 are formed. The first conductive bump 181 and the second conductive bump 182 are electrically connected to the first connection layer 171 and the second connection layer 172 through the opening O5 and the opening O6 of the second insulating layer 222, respectively. Specifically, the first conductive bump 181 is disposed corresponding to and overlapping the opening O5. The second conductive bump 182 is disposed corresponding to and overlapping the opening O6. Under the above configuration, the first conductive bump 181 can be electrically connected to the first conductive layer 151 through the first connection layer 171 and the first current conduction layer 161, and electrically connected to the ohmic contact layer 140 and the first type semiconductor layer 110. The second conductive bump 182 can be electrically connected to the second conductive layer 152 through the second connection layer 172 and the second current conduction layer 162, and is electrically connected to the second type semiconductor layer 130. Thus, the first conductive bump 181 can be used as a cathode of the light emitting device 1 (for example, the first type semiconductor layer is an N-type semiconductor layer), and the second conductive bump 182 can be used as an anode of the light emitting device 1 (for example, the second type semiconductor layer is a P-type semiconductor layer).

In some embodiments, the first conductive bumps 181 and the second conductive bumps 182 can be conductive pads, conductive pillars, or conductive balls. The first conductive bump 181 and the second conductive bump 182 include solder or metal. For example, the material of the first conductive bump 181 and the second conductive bump 182 includes gold (Au), tin (Sn), gold-tin alloy, tin-silver-copper alloy, or a combination thereof, but is not limited thereto.

In short, in the light emitting device 1 according to an embodiment of the invention, since the light emitting unit 100 includes the ohmic contact layer 140 electrically connected to the first type semiconductor layer 110, and the first conductive layer 151 conformally covers the ohmic contact layer 140, the first conductive layer 151 made of a metal material and the ohmic contact layer 140 having an epitaxial structure form a structure with low impedance and ohmic contact characteristics on the first type semiconductor layer 110. Thereby, the electrical property of the first type semiconductor layer 110 can be improved. In addition, the first insulating layer 221 may intensively reflect the light beam emitted by the light emitting layer 120 of the light emitting unit 100, so as to improve the light emitting effect and the light emitting rate of the light emitting device 1. Thereby, the light emitting device 1 can have excellent performance and quality. In addition, the manufacturing process of the light emitting device 1 is simple and cost-effective.

It should be noted that the following embodiments follow the reference numerals and parts of the contents of the foregoing embodiments, wherein the same reference numerals are used to indicate the same or similar elements, and the description of the same technical contents is omitted. For the description of the omitted parts, reference may be made to the foregoing embodiments, and the following embodiments will not be repeated.

Fig. 3A to 3D are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention. Fig. 3B is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention. For clarity of the drawings and ease of illustration, several elements are omitted from fig. 3A-3D. The light emitting device 1A of the present embodiment is similar to the light emitting device 1 of fig. 2A to 2N, and the main differences are, for example: the ohmic contact layer 140A includes a plurality of openings 141 and islands 142 surrounding the plurality of openings 141.

As can be seen from fig. 3A and 3B, the island 142 of the ohmic contact layer 140A may be electrically connected to the first-type semiconductor layer 110, and the opening 141 may extend in a direction perpendicular to the growth substrate 10. The opening 141 may expose a portion of the first-type semiconductor layer 110. In some embodiments, the heating process time of the ohmic contact layer 140A of the present embodiment may be shortened, or the temperature may be raised or lowered, compared to the ohmic contact layer 140 of fig. 2F, resulting in a rougher epitaxial structure of the ohmic contact layer 140A. Thereby, the contact area of the ohmic contact layer 140A can be increased.

Referring to fig. 3C and fig. 3D, a first conductive layer 151 is formed on the ohmic contact layer 140A. The first conductive layer 151 fills the opening 141 to contact the first-type semiconductor layer 110. Then, a first current conducting layer 161, a second current conducting layer 162, a first connection layer 171, a second connection layer 172, a third connection layer 173, a first conductive bump 181, a second conductive bump 182 and an insulating layer stack 220 are sequentially formed to complete the installation of the light emitting device 1A. Under the above configuration, the contact area between the first conductive layer 151 and the ohmic contact layer 140A can be increased, thereby further reducing the impedance. In addition, the bonding force of the first conductive layer 151 and the ohmic contact layer 140A may be improved. In addition, since the ohmic contact layer 140A has a plurality of openings 141, the aperture ratio can be increased to increase the light extraction effect. Thus, the performance and the structural quality of the light emitting element 100A and the light emitting device 1A can be improved.

Fig. 4A to 4C are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention. Fig. 4A is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention. Fig. 4B is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention. For clarity of the drawings and ease of illustration, several elements are omitted from fig. 4A-4C. The light emitting device 1B of the present embodiment is similar to the light emitting device 1 of fig. 2A to 2N, and the main differences are, for example: the ohmic contact layer 140B has a rough surface. Specifically, the upper surface 140T of the ohmic contact layer 140B is a rough surface, and the rough surface includes a plurality of microstructures 143. The microstructure 143 is, for example, a defect, a pit, or a rugged structure on the surface. The microstructures 143 may extend from the top surface 140T to the first-type semiconductor layer 110. The microstructures 143 may or may not extend through the ohmic contact layer 140B. With the above configuration, the micro structures 143 can increase the contact area of the ohmic contact layer 140B.

Referring to fig. 4B and 4C, a first conductive layer 151 is formed to conformally cover the ohmic contact layer 140B. Then, a first current conduction layer 161, a second current conduction layer 162, a first connection layer 171, a second connection layer 172, a third connection layer 173, a first conductive bump 181, a second conductive bump 182, and an insulating layer stack 220 are sequentially formed to complete the arrangement of the light emitting device 1B. Under the above configuration, the contact area between the first conductive layer 151 and the ohmic contact layer 140B can be increased, thereby further reducing the impedance. In addition, the bonding force of the first conductive layer 151 and the ohmic contact layer 140A may be improved. Therefore, the performance and the structural quality of the light-emitting device 1B can be improved.

Fig. 5A to 5B are schematic cross-sectional views illustrating a method for manufacturing a light emitting device according to another embodiment of the invention. Fig. 5A is a partially enlarged schematic view of an ohmic contact layer according to another embodiment of the invention. For clarity of the drawings and ease of description, several elements are omitted from fig. 5A-5B. The light emitting device 1C of the present embodiment is similar to the light emitting device 1 of fig. 2A to 2N, and the main differences are, for example: the first conductive layer 151 is disposed on the ohmic contact layer 140, and an orthographic projection of the first conductive layer 151 on the growth substrate 10 is located within an orthographic projection of the ohmic contact layer 140 on the growth substrate 10. In some embodiments, the ohmic contact layer 140 has a width W4, and the first conductive layer 151 has a width W5. Width W4 is greater than width W5. In some embodiments, width W4 is, for example, 3 microns to 100 microns. The width W5 is, for example, 1 to 100 micrometers, but not limited thereto. Under the above arrangement, the first conductive layer 151 does not directly contact the first-type semiconductor layer 110.

Then, a first current conduction layer 161, a second current conduction layer 162, a first connection layer 171, a second connection layer 172, a third connection layer 173, a first conductive bump 181, a second conductive bump 182 and an insulation layer stack 220 are sequentially formed to complete the fabrication of the light emitting device 1C. With the above arrangement, the light emitting device 1C has good performance and structural quality.

Fig. 6A to 6F are schematic cross-sectional views illustrating a method for manufacturing a light-emitting device according to another embodiment of the invention. For clarity of the drawings and ease of illustration, several elements are omitted from fig. 6A-6F. The light emitting device 1D of the present embodiment is similar to the light emitting device 1 of fig. 2A to 2N, and the main differences thereof are, for example: the light emitting device 1D further includes an insulating reflective layer 230. In detail, the step of forming the light emitting device 100 further includes forming an insulating reflective layer 230 on the light emitting layer 120, the second type semiconductor layer 130 and the second conductive layer 152 after the step of forming the second conductive layer 152.

Next, a plurality of openings O7 are formed in the insulating reflective layer 230. The opening O7 overlaps the second conductive layer 152 to expose the second conductive layer 152. In some embodiments, the material of the insulating reflective layer 230 includes a single layer or multiple layers of insulating material, or a structure alternately stacked by a plurality of insulating material layers with different refractive indexes, such as a Bragg reflector (DBR), and the alternately stacked structure of the insulating material layers with different refractive indexes includes silicon dioxide and titanium dioxide (SiO), for example₂/TiO₂) Or silicon dioxide, tantalum pentoxide (SiO)₂/Ta₂O₅) Or a stacked structure of silicon dioxide and magnesium fluoride (SiO)₂/MgF₂) The stacked structure of (1).

In an embodiment not shown, the insulating reflective layer 230 may include an upper insulating layer and a lower insulating layer and a bragg reflective layer between the upper insulating layer and the lower insulating layer.

In another embodiment, not shown, the insulating reflective layer 230 may include upper and lower insulating layers and a metal mirror between the upper and lower insulating layers. The material of the metal reflector is, for example, aluminum, silver or aluminum-copper alloy, but not limited thereto.

Under the above arrangement, the insulating reflective layer 230 can intensively reflect the light beam emitted from the light-emitting layer 120 of the light-emitting unit 100 toward the direction of the growth substrate 10, so as to improve the light-emitting effect and the light-emitting efficiency of the light-emitting device 1D.

Referring to fig. 6B and 6C, a first current conducting layer 161 is formed on the first conductive layer 151, and a second current conducting layer 161 is formed on the insulating reflective layer 230. The insulating reflective layer 230 is electrically connected to the second conductive layer 152 through the opening O7 to electrically connect with the second type semiconductor layer 130.

Then, a first insulating layer 221 is formed on the light emitting device 100 and covers the insulating reflective layer 230. The first insulating layer 221 may be a reflective layer. The first insulating layer 221 may be a single layer of reflective insulating material or include a structure in which a plurality of insulating materials having different refractive indexes are alternately stacked. The first insulating layer 221 may be a bragg reflective layer. In some embodiments, the first insulating layer 221 may include an upper insulating layer, a lower insulating layer, and a bragg reflective layer between the upper insulating layer and the lower insulating layer, but not limited thereto. Under the above configuration, the light beam emitted from the light emitting layer 120 can be reflected toward the growth substrate 10 in a concentrated manner, so as to improve the light emitting effect and the light emitting efficiency of the light emitting device 1D.

In some embodiments, the first insulating layer 221 further includes an opening O3 and an opening O4. The opening O3 and the opening O4 expose the first current conducting layer 161 and the second current conducting layer 162, respectively.

Referring to fig. 6D, a first connection layer 171, a second connection layer 172, and a third connection layer 173 are formed on the first insulation layer 211. The first connection layer 171 is electrically connected to the first current conducting layer 161 through the opening O3. The second connection layer 172 is electrically connected to the second current conducting layer 162 through the opening O4. In some embodiments, the third current conducting layer 173 is not electrically connected to the light emitting device 100 but electrically floating disposed on the first insulating layer 221. The third current conducting layer 173 can be used as a test pad for performing an electrical test on the light emitting device 1D during the manufacturing process.

Referring to fig. 6E, a second insulating layer 222 is then formed on the first insulating layer 221. The second insulating layer 222 covers the first, second, and third connection layers 171, 172, and 173. Thereby, the first, second and third connection layers 171, 172 and 173 may be isolated from each other by the first and second insulating layers 221 and 222.

In some embodiments, the second insulating layer 222 has a plurality of openings O5 and O6. The opening O5 corresponds to overlap the first connection layer 171 and expose the first connection layer 171. The opening O6 correspondingly overlaps the second connection layer 172 and exposes the second connection layer 172.

Referring to fig. 6F, a first conductive bump 181 and a second conductive bump 182 are formed. The first conductive bump 181 and the second conductive bump 182 are electrically connected to the first connection layer 171 and the second connection layer 172 through the opening O5 and the opening O6 of the second insulating layer 222, respectively. The first conductive bump 181 and the second conductive bump 182 may be conductive pads, conductive pillars, or conductive balls.

Under the above configuration, the light emitting device 1D can further improve the concentration of the light beam emitted from the light emitting layer 120 through the insulating reflective layer 230, so as to improve the light emitting effect and quality. In addition, the light-emitting device 1D has good performance and structural quality.

Fig. 7A to 7C are schematic cross-sectional views illustrating a method of manufacturing a light emitting device according to still another embodiment of the invention. For clarity of the drawings and ease of illustration, several elements are omitted from fig. 7A-7C. The light emitting device 1E of the present embodiment is similar to the light emitting device 1D of fig. 6A to 6F, and the main differences are, for example: the light emitting device 1E further includes a plurality of conductive members 190 disposed on the second conductive layer 152. The material of the conductive element 190 is similar to that of the first conductive layer 151, and therefore, the description thereof is omitted.

The orthographic projection of any one of the conductive members 190 on the growth substrate 10 overlaps the orthographic projection of the second conductive layer 152 on the growth substrate 10. In some embodiments, the orthographic projection of the conductive member 190 on the growth substrate 10 is located in the orthographic projection of the second conductive layer 152 on the growth substrate 10. In other embodiments, the orthographic projection area of the conductive member 190 on the growth substrate 10 is smaller than the orthographic projection area of the first conductive layer 151 on the growth substrate 10.

In some embodiments, the insulating reflective layer 230 is disposed on the second type semiconductor layer 130 and the second conductive layer 152. The insulating reflective layer 230 has a plurality of openings O7. Opening O7 overlaps conductive element 190 to expose conductive element 190.

Referring to fig. 7B and 7C, a first current conducting layer 161 is formed on the first conductive layer 151, and a second current conducting layer 161 is formed on the insulating reflective layer 230. The insulating reflective layer 230 is electrically connected to the conductive member 190 through the opening O7 to electrically connect with the second type semiconductor layer 130.

Then, the first connection layer 171, the second connection layer 172, the third connection layer 173, the first conductive bump 181, the second conductive bump 182 and the insulating layer stack 220 are sequentially formed to complete the installation of the light emitting device 1E. Under the above configuration, the light emitting device 1E can further reduce the impedance of the second conductive layer 152 and the second current conductive layer 162 through the conductive member 190. The light-emitting device 1E has good performance and structural quality.

In summary, in the light emitting device according to an embodiment of the invention, the ohmic contact layer is electrically connected to the first type semiconductor layer, and the first conductive layer contacts the ohmic contact layer, so that the first conductive layer made of a metal material and the ohmic contact layer of the epitaxial structure form a structure with low impedance and ohmic contact characteristics on the first type semiconductor layer. Thereby, the electrical property of the first type semiconductor layer can be improved. In addition, the first insulating layer or the insulating reflective layer can intensively reflect the light beam emitted by the light emitting layer of the light emitting unit, so that the light emitting effect and the light emitting rate of the light emitting device are improved. Thus, the light emitting device can have excellent performance and quality. In addition, the manufacturing process of the light-emitting device can be simple and cost-saving.