阅读说明：本技术 一种半导体器件、led芯片及其转移方法 (Semiconductor device, LED chip and transfer method thereof ) 是由 夏继业 董小彪 姚志博 王岩 盛翠翠 王程功 于 2020-05-29 设计创作，主要内容包括：本发明提供了一种半导体器件和LED芯片及其转移方法,LED芯片包括电极,通过在该电极背离LED芯片其他膜层的一侧设置凹槽,在LED芯片转移时利用该凹槽保护凹槽内部的键合材料不被刻蚀,从而可以实现只保留腔室区域内的键合材料,以实现LED芯片在转移过程中与基板之间的粘附力一致,继而提高LED芯片的拾取良率。(The invention provides a semiconductor device, an LED chip and a transfer method thereof, wherein the LED chip comprises an electrode, one side of the electrode, which is far away from other film layers of the LED chip, is provided with a groove, and bonding materials in the groove are protected from being etched by using the groove when the LED chip is transferred, so that the bonding materials in a cavity area can be reserved only, the consistency of the adhesive force between the LED chip and a substrate in the transfer process is realized, and the pick-up yield of the LED chip is improved.)

1. An LED chip, comprising:

an electrode; and one side of the electrode, which deviates from other film layers of the LED chip, is provided with a groove.

2. The LED chip of claim 1, wherein said recess is open along a side of said LED chip in a thickness direction.

3. The LED chip of claim 2, wherein the minimum width of the opening is less than half of the width corresponding to the side where the opening is located.

4. The LED chip according to claim 2, wherein an orthographic projection shape of the opening in a thickness direction of the LED chip comprises any one of: trapezoidal, arc, square.

5. A semiconductor device, comprising:

a substrate;

the bonding layer is arranged on one side surface of the substrate; wherein the bonding layer includes a bonding material therein; and

the LED chip is embedded in the bonding layer and connected with the substrate;

wherein the LED chip comprises the LED chip according to any one of claims 1 to 4, the electrode of the LED chip being connected to the substrate.

6. The semiconductor device according to claim 5, wherein a thickness of the bonding layer in a stacking direction of the substrate and the bonding layer is smaller than a thickness of the LED chip in the stacking direction.

7. A method for transferring an LED chip is characterized in that the LED chip comprises an electrode, a groove is arranged on one side of the electrode, which is far away from other film layers of the LED chip, and the transferring method comprises the following steps:

preparing or obtaining a substrate;

coating a bonding layer on one side surface of the substrate;

embedding the side of the LED chip where the electrode is located into the bonding layer and connecting the LED chip with the substrate;

transferring the LED chip; and

and etching the bonding layer.

8. The transfer method of claim 7, wherein the etching the bonding layer comprises:

and etching the bonding layer by introducing dry etching.

9. The transfer method of claim 8, wherein the etching the bonding layer comprises:

and introducing corrosive gas to etch the bonding layer.

10. The transfer method according to claim 7, wherein the groove is provided with an opening along a side surface in a thickness direction of the LED chip, and the etching the bonding layer comprises:

etching away the bonding layer outside the groove.

Technical Field

The invention relates to the technical field of display, in particular to a semiconductor device, an LED chip and a transfer method thereof.

Background

In the existing manufacturing process of the display panel, when laser is stripped, the adhesion between the light emitting diode and the temporary substrate needs to be strong enough, and in the subsequent light emitting diode pickup process, the adhesion between the light emitting diode and the temporary substrate needs to be small as much as possible, so that the pickup yield of the light emitting diode is improved.

However, in the temporary substrate post-processing process, the problem of low pickup yield of the light emitting diode still exists.

Disclosure of Invention

In view of the above, embodiments of the present invention are directed to a semiconductor device, an LED chip and a transfer method thereof, which can improve the pick-up yield of the LED chip.

According to an aspect of the present invention, an embodiment of the present invention provides an LED chip, including: an electrode; and one side of the electrode, which deviates from other film layers of the LED chip, is provided with a groove.

In one embodiment, the groove is provided with an opening along the side surface of the thickness direction of the LED chip.

In an embodiment, the minimum width of the opening is smaller than half of the width corresponding to the side surface where the opening is located.

In an embodiment, an orthographic projection shape of the opening in the thickness direction of the LED chip includes any one of the following shapes: trapezoidal, arc, square.

According to another aspect of the present invention, an embodiment of the present invention provides a semiconductor device, including: a substrate; the bonding layer is arranged on one side surface of the substrate; wherein the bonding layer includes a bonding material therein; and an LED chip embedded in the bonding layer and connected with the substrate; wherein the LED chip comprises the LED chip as described in any one of the above, and the electrode of the LED chip is connected with the substrate.

In one embodiment, the thickness of the bonding layer in the stacking direction of the substrate and the bonding layer is smaller than the thickness of the LED chip in the stacking direction.

According to another aspect of the present invention, an embodiment of the present invention provides a method for transferring an LED chip, where the LED chip includes an electrode, and a side of the electrode facing away from other film layers of the LED chip is provided with a groove, and the method includes: preparing or obtaining a substrate; coating a bonding layer on one side surface of the substrate; embedding the side of the LED chip where the electrode is located into the bonding layer and connecting the LED chip with the substrate; transferring the LED chip; and etching the bonding layer.

In one embodiment, the etching the bonding layer includes: and etching the bonding layer by introducing dry etching.

In one embodiment, the etching the bonding layer includes: and introducing corrosive gas to etch the bonding layer.

In an embodiment, the groove is provided with an opening along a side surface in a thickness direction of the LED chip, and the etching the bonding layer includes: etching away the bonding layer outside the chamber region.

According to the semiconductor device, the LED chip and the transfer method thereof, the LED chip comprises the electrode, the groove is arranged on one side of the electrode, which is far away from other film layers of the LED chip, and bonding materials in the groove are protected from being etched by the groove when the LED chip is transferred, so that the bonding materials in a cavity area can be reserved only, the consistency of the adhesion force between the LED chip and a substrate in the transfer process is realized, and the pick-up yield of the LED chip is improved.

Drawings

Fig. 1 is a schematic cross-sectional view of an LED chip transfer along a direction perpendicular to a thickness direction according to an embodiment of the present disclosure.

Fig. 2 is a schematic cross-sectional view of an LED chip transfer along a direction perpendicular to a thickness direction according to another embodiment of the present disclosure.

Fig. 3 is a schematic cross-sectional view of an LED chip transfer along a direction perpendicular to a thickness direction according to another embodiment of the present disclosure.

Fig. 4 is a schematic structural diagram of a semiconductor device according to an embodiment of the present application.

Fig. 5 is a flowchart illustrating an LED chip transferring method according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Further, in the exemplary embodiments, since the same reference numerals denote the same components having the same structure or the same steps of the same method, if an embodiment is exemplarily described, only a structure or a method different from the already described embodiment is described in other exemplary embodiments.

Throughout the specification and claims, when one element is described as being "connected" to another element, the one element may be "directly connected" to the other element or "electrically connected" to the other element through a third element. Furthermore, unless explicitly described to the contrary, the term "comprising" and its corresponding terms should only be taken as including the stated features, but should not be taken as excluding any other features.

A general batch transfer Light Emitting Diode (LED) includes five processes: temporary bonding, laser stripping, temporary substrate post-processing, light-emitting diode pickup and light-emitting diode bonding. In the existing manufacturing process of the display panel, when laser is stripped, the adhesion between the light emitting diode and the temporary substrate needs to be strong enough, and in the subsequent light emitting diode pickup process, the adhesion between the light emitting diode and the temporary substrate needs to be small as much as possible, so that the pickup yield of the light emitting diode is improved. Therefore, the post-treatment process of the temporary substrate is particularly important, the adhesion force of the light-emitting diode and the temporary substrate is changed through the post-treatment, and the LED batch transfer technology with higher yield can be developed. The inventors have found that in the temporary substrate post-treatment process, the material that achieves adhesion between the light emitting diode and the temporary substrate is usually etched away, but due to the non-uniform etching window, the adhesion difference between each LED and the temporary substrate is large, and thus the pick-up yield of the final LED is not high. In order to improve the pickup yield, the inventors propose the following scheme.

Fig. 1 is a schematic cross-sectional view of an LED chip along a direction perpendicular to a thickness direction according to an embodiment of the present disclosure. As shown in fig. 1, the LED chip 3 includes an electrode 30 and other film layers, wherein the electrode 30 is located at a side of the LED chip 3, and a groove 31 is provided at a side of the electrode 30 facing away from the other film layers, that is, the groove 31 is provided at the side of the electrode 30 of the LED chip 3.

The embodiment of the application utilizes the groove 31 arranged on one side of the electrode 30 to form a protection space for the adhesive material inside the groove 31, namely, in the temporary substrate post-treatment process, only the adhesive material outside the groove 31 is etched, and the adhesive material inside the groove 31 is reserved, so that certain adhesive force can be ensured to exist between the LED chip and the substrate, meanwhile, the uniformity of the adhesive material in the groove 31 can also be ensured, the consistency of the adhesive force between the LED chip and the substrate is ensured, and the picking yield of the final light-emitting diode is improved. It should be understood that the LED chip in the embodiments of the present application may be a micro LED chip. It is understood that the groove 31 may not penetrate the electrode 30 in the thickness direction of the LED chip, and may penetrate the electrode 30.

According to the LED chip provided by the embodiment of the invention, the LED chip comprises the electrode, the groove is arranged on one side of the electrode, which is far away from other film layers of the LED chip, and the bonding material in the groove is protected from being etched by the groove when the LED chip is transferred, so that the bonding material in the cavity area can be reserved only, the consistency of the adhesive force between the LED chip and the substrate in the transfer process is realized, and the pick-up yield of the LED chip is improved.

In one embodiment, as shown in fig. 1, an opening 32 may be provided on a side surface of the groove 31 in the thickness direction of the LED chip 3. That is, an opening 32 is provided on a side surface of the electrode 30 in the thickness direction of the LED chip 3 to realize communication of the groove 31 with the outside of the electrode 30 through the opening 32. By providing the opening 32, when the substrate 1 and the LED chip 3 are peeled off at a later stage, the bonding material inside the chamber region 31 may be further processed by the opening 32, so that the peeling operation between the substrate 1 and the LED chip 3 is smoothly performed. In a further embodiment, as shown in fig. 1, the LED chip 3 includes two electrodes 30 disposed side by side and close to each other, a groove 31 is disposed on each of the two electrodes 30, and an opening 32 may be disposed on a surface of each of the two grooves 31 opposite to each other. Through all setting up recess 31 on two electrodes 30, can avoid adhesion to concentrate and the promotion of the degree of difficulty of peeling off that brings when guaranteeing the adhesion between base plate and the LED chip 3, and set up opening 32 respectively in two relative one sides of recess 31, can utilize the position characteristic that two electrodes 30 are close to each other to provide certain effect of sheltering from for the other side, when handling the bonding material of recess 31 outside promptly, can avoid the bonding material of recess 31 inside to be handled as far as possible, thereby adhesion strength and homogeneity between base plate and the LED chip 3 have been guaranteed. It should be understood that the number of the grooves 31 and the number of the openings 32 may be selected according to the requirements of practical application scenarios, and the number of the grooves 31 and the number of the openings 32 may be 1 or more, as long as the number of the grooves 31 and the openings 32 selected can ensure the adhesive strength and uniformity between the substrate and the LED chip 3, and the specific number of the grooves 31 and the openings 32 is not limited in the embodiments of the present application.

In one embodiment, as shown in fig. 1, the minimum width D of the opening 32 is less than half of the width D corresponding to the side where the opening 32 is located. If the width of the opening 32 is too large, a part or a larger part of the bonding material inside the groove 31 may be disposed during the process of disposing the bonding material, or even all of the bonding material may be disposed, so that the adhesion between the substrate and the LED chip 3 is insufficient, which obviously is not favorable for the subsequent process, and of course, the pickup yield of the LED chip 3 may be reduced. Therefore, in the embodiment of the present application, the width D of the opening 32 is set to be less than half of the width D of the side surface where the opening 32 is located (i.e. the width of the electrode 30 on the side where the opening 32 is located), so that in the process of processing the bonding material, the influence degree on the bonding material inside the groove 31 can be effectively reduced, and the adhesion strength and uniformity between the substrate and the LED chip 3 are ensured. It should be understood that the width of the opening 32 may be selected according to the requirement of the practical application scenario, as long as the width of the opening 32 is selected to avoid the influence on the bonding material inside the groove 31 during the process of processing the bonding material, and the specific width of the opening 32 is not limited in the embodiment of the present application.

In an embodiment, the orthographic projection shape of the groove 31 in the thickness direction of the LED chip 3 may include any one of the following shapes: trapezoidal, arc, square. The smaller the area inside the groove 31, the less the bonding material contained inside the groove 31, resulting in insufficient adhesion between the substrate and the LED chip 3; if the opening 32 on the groove 31 is too large, the bonding material inside the groove 31 may be greatly affected during the process of handling the bonding material, resulting in insufficient or inconsistent adhesion between the substrate and the LED chip 3. Therefore, in the embodiment of the present application, for the purpose of ensuring that the groove 31 has a certain internal area and the width of the opening 32 is small, the shape of the groove 31 may be set to be trapezoidal (as shown in fig. 1), and a shorter side of the trapezoidal shape is located on one side of the opening 32, so that the width of the opening 32 is small while the internal area of the groove 31 is large, that is, the adhesive strength and consistency between the substrate and the LED chip 3 are simultaneously ensured. For the above analysis, the shape of the groove 31 may be set to be an arc (as shown in fig. 2), and the radian of the arc is greater than 180 degrees, so that the width of the opening 32 can be ensured to be smaller while the inner area of the groove 31 is ensured to be larger, that is, the adhesive strength and consistency between the substrate and the LED chip 3 are ensured. On the premise of satisfying the adhesive strength between the substrate and the LED chip 3, the groove 31 may be set to be square (as shown in fig. 3), which is a structure with a shorter width and a longer length, that is, the inner area of the groove 31 is increased as much as possible while the width of the opening 32 (corresponding to the width of the square) is ensured to be smaller, thereby ensuring the adhesive strength and consistency between the substrate and the LED chip 3. It should be understood that the embodiment of the present application may select different shapes of the groove 31 according to requirements of practical application scenarios, as long as the selected shape of the groove 31 can achieve that the internal area of the groove 31 meets the requirements and the width of the opening 32 is small, so as to avoid the influence on the bonding material inside the groove 31 in the process of processing the bonding material.

Fig. 4 is a schematic structural diagram of a semiconductor device according to an embodiment of the present application. As shown in fig. 4, the semiconductor device includes: the LED chip comprises a substrate 1, a bonding layer 2 and an LED chip 3 which are arranged in a stacked mode. The bonding layer 2 is arranged on one side surface of the substrate 1, the bonding layer 2 comprises a bonding material, the LED chip 3 is embedded in the bonding layer 2 and connected with the substrate 1, the LED chip 3 may comprise the LED chip 3 according to any of the embodiments, and the electrode 30 of the LED chip 3 is connected with the substrate 1.

Generally, after the LED chip 3 is prepared on the sapphire, the substrate 1 and the LED chip 3 are bonded to each other and then the LED chip 3 is peeled off from the sapphire, thereby transferring the LED chip 3. When the LED chip 3 is peeled off from the sapphire and transferred, the adhesion force between the substrate 1 and the LED chip 3 needs to be large enough to ensure that the LED chip 3 does not separate from the substrate 1, at this time, in order to ensure the adhesion strength between the LED chip 3 and the substrate 1, the bonding layer 2 is arranged between the substrate 1 and the LED chip 3, and the bonding between the substrate 1 and the LED chip 3 is realized by using the bonding material in the bonding layer 2. For the purpose of improving the adhesion between the substrate 1 and the LED chip 3, the LED chip 3 is embedded into the bonding layer 2 and connected with the substrate 1, and it is ensured that the bonding material in the bonding layer 2 fills the gap between the substrate 1 and the LED chip 3, thereby ensuring the adhesion between the substrate 1 and the LED chip 3. After the LED chips 3 are peeled off and transferred from the sapphire, the adhesion between the substrate 1 and the LED chips 3 needs to be weakened (but the substrate 1 and the LED chips 3 cannot be peeled off directly) to reduce the difficulty in subsequently peeling the LED chips 3 off the substrate 1, so that the bonding layer 2 between the substrate 1 and the LED chips 3 (or the bonding material in the bonding layer 2) needs to be processed, since the gap between the substrate 1 and the LED chips 3 is small, when the bonding material in the bonding layer 2 is processed, the processing speed is difficult to be consistent, and a part of the bonding material needs to be reserved, which causes different amounts of the bonding material reserved between each LED chip 3 and the substrate 1, even the bonding material between the same LED chip 3 and the substrate 1, and thus causes inconsistent adhesion between each LED chip 3 and the substrate 1, this affects the pick-up yield of the subsequent LED chips 3. Since the side of the LED chip 3 close to the bonding layer 2 includes the electrode 30, that is, the electrode 30 is also embedded into the bonding layer 2, in the embodiment of the present application, the bottom of the electrode 30 (that is, the side close to the substrate 1) is provided with the groove 31, in the process of embedding the electrode 30 into the bonding layer 2, the bonding material in the bonding layer 2 fills the groove 31, and the electrode 30 is connected to the substrate 1, that is, the side of the groove 31 close to the substrate 1 is sealed, when the bonding layer 2 is processed, the bonding material in the groove 31 is not processed from the side close to the substrate 1, so that it can be ensured that the bonding material in the groove 31 is not processed or is processed in a very small amount, that the bonding material outside the groove 31 can be processed, it is ensured that the bonding material between the substrate 1 and the LED chip 3 is only present in the groove 31, so that while a certain adhesion between the substrate 1 and the LED chip 3 is ensured, the adhesion consistency between each LED chip 3 and the substrate 1 is also ensured, so that the pick-up yield of the subsequent LED chips 3 is improved.

According to the semiconductor device provided by the embodiment of the invention, the bonding layer is arranged on the surface of one side of the substrate, the bonding layer comprises the bonding material, the LED chip is embedded into the bonding layer and connected with the substrate, so that the bonding connection between the LED chip and the substrate is realized, the side, close to the bonding layer, of the LED chip comprises the electrode, the side, close to the substrate, of the electrode is provided with the groove, when the LED chip is bonded with the substrate, the bonding material is filled in the groove, and because the LED chip is connected with the substrate, the bonding material in the groove cannot be etched from one side of the substrate during etching, so that the bonding material in the groove can be reserved only, the consistency of the adhesive force between each LED chip and the substrate is realized, and the picking yield of the LED chips is improved.

In an embodiment, the thickness of the bonding layer 2 in the stacking direction of the substrate 1 and the bonding layer 2 may be smaller than the thickness of the LED chip 3 in the stacking direction. In order to ensure that the electrode 30 on the LED chip 3 can be contacted with the substrate 1, the thickness of the bonding layer 2 along the stacking direction of the substrate 1 and the bonding layer 2 is smaller than the thickness of the LED chip 3 along the stacking direction, so that the electrode 30 on one side of the LED chip 3 can be ensured to be contacted with the substrate 1 when the LED chip 3 is embedded into the bonding layer 2, one side of the groove 31 close to the substrate 1 is ensured to be connected with the substrate 1 in a sealing manner, and the bonding material in the groove 31 is prevented from being processed from one side of the substrate 1 in the process of processing the bonding layer 2. It should be understood that, in the embodiment of the present application, different thicknesses of the bonding layer 2 may be selected according to requirements of practical application scenarios, as long as the selected thickness of the bonding layer 2 can ensure that the electrode 30 is in contact with the substrate 1 to seal the groove 31, and the specific thickness of the bonding layer 2 is not limited in the embodiment of the present application.

In an embodiment, the bonding layer 2 may include any one of the following layers of glue: photoresist, silicon-based adhesive, epoxy resin adhesive. It should be understood that different materials of the bonding layer 2 may be selected according to the requirements of the actual application scenario, as long as the selected material of the bonding layer 2 can ensure the adhesion between the substrate 1 and the LED chip 3.

Fig. 5 is a flowchart illustrating an LED chip transferring method according to an embodiment of the present application. The LED chip includes an electrode, and a groove (the specific structure is as described in the above embodiment) is disposed on a side of the electrode away from other film layers of the LED chip, as shown in fig. 5, the LED chip transferring method includes the following steps:

step 510: a substrate is prepared or obtained.

The substrate 1 may be prepared, or the existing substrate 1 may be directly obtained, and the substrate 1 in the embodiment of the present application may be a rigid substrate such as a glass substrate, or may be a substrate of another type or material, which is not limited in the embodiment of the present application.

Step 520: and coating a bonding material on one side surface of the substrate.

The bonding layer 2 is formed by coating a bonding material on one side surface of the substrate 1.

Step 530: and embedding the side of the LED chip where the electrode is positioned into the bonding material and connecting the LED chip with the substrate.

The side of the LED chip 3 where the electrode 30 is located is embedded in the bonding layer 2 and the electrode 30 contacts the substrate 1 to ensure a hermetic connection of the electrode 30 with the substrate 1.

Step 540: the LED chips are transferred.

After the bonding layer 2 is used for adhering the substrate 1 and the LED chip 3, the LED chip 3 can be transferred.

Step 550: and etching the bonding layer.

Through etching bonding layer 2, realize all etching away the bonding material of recess 31 outside to only guarantee the bonding material of recess 31 inside between base plate 1 and the LED chip 3, then when guaranteeing the adhesion strength between base plate 1 and the LED chip 3, guaranteed the adhesion uniformity between each LED chip 3 and the base plate 1, be favorable to improving the yield of picking up of LED chip 3. In an embodiment, a specific implementation manner of etching the bonding layer may include: the bonding material is etched by dry etching. In further embodiments, the implementation may include: and introducing corrosive gas to etch the bonding material. In an embodiment, the recess is provided with an opening on a surface adjacent to the substrate, and etching the bonding layer may include: the bonding material outside the recess is etched away. It should be understood that, in the embodiment of the present application, different etching manners, such as wet etching, may be selected according to requirements of an actual application scenario, as long as the selected etching manner can achieve etching of the bonding material outside the groove 31, and the specific etching manner is not limited in the embodiment of the present application.

According to the LED chip transfer method provided by the embodiment of the invention, the bonding material is coated on the surface of one side of the substrate to form the bonding layer, the side where the electrode of the LED chip is located is embedded into the bonding material and connected with the substrate, the bonding material is filled in the groove when the LED chip is bonded with the substrate, and the bonding material in the cavity region cannot be etched from one side of the substrate when the LED chip is connected with the substrate, so that the bonding material in the groove can be reserved only, the consistency of the adhesive force between each LED chip and the substrate is realized, and the pick-up yield of the LED chip is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and the like that are within the spirit and principle of the present invention are included in the present invention.