阅读说明：本技术 一种基于氮化镓材料的光继电器 (Optical relay based on gallium nitride material ) 是由 郭伟玲 郭浩 蔺天宇 程海娟 朱彦旭 于 2020-10-28 设计创作，主要内容包括：本发明公开了一种基于氮化镓材料的光继电器,整个光继电器内部器件的制备方式是是氮化镓发光器件、氮化镓光电转换器件和氮化镓高电子迁移率晶体管制备于三个独立芯片,而后进行封装集成；相比较传统基于Si基器件的半导体继电器来说,基于GaN材料的器件光电转化效率高、器件响应速度提高,同时拥有了更高的击穿电压。此外,本发明还将GaN基发光和光电转换器件集成于同一衬底上以及将发光器件、光电转换器件、高电子迁移率晶体管集成在同一衬底上并进行封装,这提高了器件性能,减少了集成封装步骤,同时减小了光电继电器的体积。(The invention discloses a gallium nitride material-based optical relay.A preparation method of an internal device of the whole optical relay is that a gallium nitride luminescent device, a gallium nitride photoelectric conversion device and a gallium nitride high electron mobility transistor are prepared in three independent chips and then are packaged and integrated; compared with the traditional semiconductor relay based on the Si-based device, the GaN-based device is high in photoelectric conversion efficiency, high in response speed and high in breakdown voltage. In addition, the GaN-based light emitting device and the photoelectric conversion device are integrated on the same substrate, and the light emitting device, the photoelectric conversion device and the high electron mobility transistor are integrated on the same substrate and packaged, so that the device performance is improved, the integrated packaging steps are reduced, and the size of the photoelectric relay is reduced.)

1. An optical relay based on gallium nitride material, characterized in that: comprises more than one light-emitting device, more than one photoelectric conversion device and more than two high electron mobility transistors; the light-emitting device, the photoelectric conversion device and the high electron mobility transistor are all prepared by growing gallium nitride materials; carrying out COB (chip on Board) packaging on the light-emitting device and the photoelectric conversion device chip, and enabling the light-emitting device to face the photoelectric conversion device; or encapsulating the light emitting device and the photoelectric conversion device in a transparent encapsulating layer having a highly reflective coating on the surface; the light emitting device is connected to the input end of the optical relay, the output end of the photoelectric conversion device is connected with the input ends of the high electron mobility transistors, namely the grid and the source, the sources of the two high electron mobility transistors are connected, and the drains of the two high electron mobility transistors are connected to the output end of the optical relay.

2. An optical relay according to claim 1, wherein said light emitting device is a gan led; the photoelectric conversion device is a gallium nitride photoelectric conversion element; the high electron mobility transistor is a gallium nitride high electron mobility transistor.

3. The optical relay according to claim 1, wherein the light emitting device, the photoelectric conversion device and the high electron mobility transistor are packaged independently, and are combined together through a circuit board.

4. The optical relay according to claim 3, wherein the light emitting device, the photoelectric conversion device, and the high electron mobility transistor are fabricated by integrating the light emitting device and the photoelectric conversion device on a same chip; or the light-emitting device, the photoelectric conversion device and the high electron mobility transistor are integrated on the same chip.

5. An optical relay based on gallium nitride material according to claim 1, wherein: the light emitting device is a green light emitting unit, a blue light emitting unit, a cyan light emitting unit or an ultraviolet light emitting unit, and the light emitting device is of a flip chip structure or a front chip structure.

6. An optical relay based on gallium nitride material according to claim 1, wherein: the photoelectric conversion device is a green light-sensitive unit, a blue light-sensitive unit, a cyan light-sensitive unit, or an ultraviolet light-sensitive unit.

7. The optical relay of claim 1 wherein the high electron mobility transistor is an enhancement mode device or a depletion mode device.

Technical Field

The present invention relates to an optical relay of a semiconductor device, and more particularly, to an optical relay device using a GaN material as a light emitting material, a photoelectric conversion material, and a driver, and belongs to the technical field of power management.

Background

The semiconductor relay is small in on-resistance, can control a minute analog signal, and is small in size, and therefore can be applied to various scenes.

With the continuous optimization and development of the structure and the process of the Si-based device, the performance development of the Si material is approaching to the limit, and it is difficult to meet the requirement of the power electronic field for higher performance of the electronic device, and it becomes very difficult to continue to improve the electrical performance of the device through the improvement of the structure and the process of the device.

In the third generation of semiconductors, GaN is a research hotspot of wide-bandgap semiconductor power devices, has the characteristics of large forbidden bandwidth, high critical breakdown electric field, high electron drift saturation velocity, high thermal conductivity, good chemical stability and the like, meets the development requirements of future power semiconductor devices towards high power, high frequency, high speed, high reliability and high integration, and is particularly suitable for the development of future power electronic devices. Compared with silicon, gallium nitride has higher breakdown electric field intensity, and the resistance and the breakdown voltage of the gallium nitride are more advantageous, so that the size of a device can be smaller under a given breakdown voltage, and the device is more consistent with the development trend of future power electronics.

GaN is a core material for semiconductor illumination, and has very important applications and significances in semiconductor illumination and beyond illumination fields due to its high luminous efficiency and wide wavelength range. In the aspect of photoelectric conversion, gallium nitride is taken as a detector, and the gallium nitride gradually breaks through the limitation of the application aspect of silicon-based materials due to the advantages of wider direct band gap, stable physical and chemical properties, easiness in improving quantum efficiency and the like. With the continuous improvement of the quality, the continuous expansion of the epitaxial dimension and the gradual maturity of the process technology level of the AlGaN/GaN heterojunction electronic material, the frequency and the performance of the GaN HEMT electronic device are continuously improved, while the cost is continuously reduced, which also accelerates the application, the popularization and the commercialization of the nitride electronic device in the market. Wherein the enhancement mode will provide faster and more stable turn-on and turn-off speeds, and is also more easily integrated, whether chip-level or package-level.

Therefore, the gallium nitride material is used for replacing a silicon-based device in the traditional semiconductor relay, so that the photoelectric conversion efficiency can be improved, the response speed of the device can be improved, and the output capacity can be improved. The development requirements of the future power electronic field are met.

Fig. 1 is a schematic diagram of a typical optical relay. As shown in the drawing, the photo-relay a1 includes a light emitting element L1, a photoelectric conversion module L2, and an output module L3 including two mosfets. The light emitting device L1, which may be a Light Emitting Diode (LED), is connected to the input terminals T1 and T2 of the optical relay a1 to receive a current signal and generate an optical signal according to the current signal; the photoelectric conversion module L2 includes a photodiode array and circuits; the sources of the two mos transistors in the output module L3 are connected, and the drains thereof are connected to the output terminals T3 and T4 of the photo relay a1, respectively. After receiving the optical signal from the light emitting element L1, the photodiode array of the photoelectric conversion module L2 generates a corresponding voltage drop and outputs the voltage drop to the gate and source electrodes of the mosfet to control the on-state of the two mosfets, thereby controlling the current flowing through the two mosfets.

Disclosure of Invention

The invention aims to meet the development requirements in the field of power electronics, and provides a novel optical relay based on a GaN material. The relay is provided with: the light emitting device includes one or more light emitting devices, one or more photoelectric conversion devices, and two or more high electron mobility transistors. The light emitting device faces the photoelectric conversion device, and the output end of the photoelectric conversion device is connected with the input end (i.e., the gate and the source) of the high electron mobility transistor. And all the devices are prepared by adopting gallium nitride material growth. The gallium nitride high electron mobility transistor may be an enhancement mode device or a depletion mode device.

Because all devices are prepared by adopting gallium nitride material growth, the device performance can be improved and the integrated packaging steps can be reduced by preparing the devices on the same substrate and chip.

The preparation process taking the normally-installed GaN-based LED as an example comprises the following steps: firstly, cleaning the LED epitaxial wafer. The epitaxial wafer is then etched using an inductively coupled plasma until the N-GaN is exposed. Then make itDeposition of SiO by plasma enhanced chemical vapor deposition₂As a current blocking layer. And evaporating the ITO film by using an electron beam, and obtaining an ITO pattern by photoetching and wet etching. Followed by SiO deposition using PECVD₂As a passivation layer. Sputtering Cr/Al/Ti/Pt/Ti/Au laminated metal electrode.

The GaN-based p-i-n type photoelectric detector comprises the following preparation process flows: the epitaxial wafer is first cleaned. Preparing an ITO conductive layer by using electron beam evaporation, then etching an epitaxial wafer by using inductively coupled plasma to expose an N-GaN layer, then depositing a Ti/Al/Ni/Au metal electrode on an N-type table top by using electron beam evaporation, depositing a Ni/Au P metal electrode on a P-type layer, and finally preparing SiO by using Plasma Enhanced Chemical Vapor Deposition (PECVD)₂Passivation layers to isolate and protect the devices.

The technological process of the GaN-based enhanced AlGaN/GaN HEMT comprises the following steps: preparing a GaN-based enhanced AlGaN/GaN HEMT by using Metal Organic Chemical Vapor Deposition (MOCVD) or Molecular Beam Epitaxy (MBE), cleaning a sapphire substrate, drying, and then sequentially growing a GaN low-temperature layer, a GaN epitaxial layer and an AlGaN layer. After the AlGaN/GaN heterojunction is prepared, a fluorine ion injection window below a grid electrode is prepared through photoetching, fluorine ion injection under the grid electrode is carried out to prepare an enhanced AlGaN/GaN HEMT, and a Ti/Al/Ni/Au metal electrode is deposited through electron beam evaporation.

After preparing and obtaining a GaN-based LED, a photoelectric conversion device chip and a high mobility electronic transistor, packaging the GaN-based light emitting device chip and the photoelectric conversion device chip in hemispherical transparent resin, covering a high reflection coating on the hemispherical transparent resin, and packaging the hemispherical transparent resin and the output part of the GaN-based light emitting device chip and the photoelectric conversion device chip with a GaN HEMT chip to obtain a novel optical relay with the light emitting device and the photoelectric conversion device integrated on the same chip; and carrying out COB (chip on Board) packaging or packaging in hemispherical transparent resin on the GaN-based light emitting device and the photoelectric conversion device, and then integrating the packaged GaN-based light emitting device and the packaged photoelectric conversion device on a reserved position of a GaN-based high-mobility electronic transistor substrate to obtain the novel optical relay in which the light emitting device, the photoelectric conversion device and a GaN HEMT (high electron mobility transistor) chip of an output part are integrated on the same chip.

Thus, there are three ways to grow and fabricate the device. The preparation method of the internal device of the whole optical relay can be that a gallium nitride luminescent device, a gallium nitride photoelectric conversion device and a gallium nitride high electron mobility transistor are prepared on three independent chips and then are packaged and integrated; the gallium nitride light-emitting device and the gallium nitride photoelectric conversion device can be integrated on the same substrate; the gallium nitride light-emitting device, the gallium nitride photoelectric conversion device and the gallium nitride high electron mobility transistor can be integrated on the same substrate.

Compared with the traditional semiconductor relay based on a Si-based device, the GaN-based device has the advantages of high photoelectric conversion efficiency, high response speed and higher breakdown voltage. In addition, the GaN-based light emitting device and the photoelectric conversion device are integrated on the same substrate, and the light emitting device, the photoelectric conversion device and the high electron mobility transistor are integrated on the same substrate and packaged, so that the device performance is improved, the integrated packaging steps are reduced, and the size of the photoelectric relay is reduced.

Drawings

The purpose and features of the present invention will become apparent from the following description of the embodiments provided together with fig. 1.

FIG. 1 is an equivalent circuit diagram of a typical semiconductor optical relay;

FIG. 2 is a schematic structural diagram of a GaN-based flip-chip LED device according to the present invention;

FIG. 3 is a schematic structural view of a GaN-based forward-mounted LED device according to the present invention;

FIG. 4 is a schematic structural view of a GaN photoelectric conversion device in the present invention;

FIG. 5 is a schematic view of a GaN HEMT device in accordance with the present invention;

FIG. 6 is a schematic structural diagram of an output portion of two source interconnected GaN HEMT devices of the present invention;

fig. 7 is a schematic cross-sectional structure of an optical relay in embodiment 1;

fig. 8 is a schematic cross-sectional structure of an optical relay in embodiment 2;

fig. 9 is a schematic cross-sectional structure of an optical relay in embodiment 3;

fig. 10 is a schematic cross-sectional structure of an optical relay in embodiment 3;

in the figure: a1: optical relay

T1, T2, T5, T6: input pin

T3, T4, T7, T8: output pin

L1: light emitting element

L2: photoelectric conversion module

L3: output module

H1, H2: high electron mobility transistor

C1: photoelectric conversion element circuit

F1: transparent encapsulation layer of resin

F2: high reflective coating

F3: outer packaging layer of optical relay

G: lead frame

W1-W6: conducting wire

X: substrate

P1: light-emitting element and photoelectric conversion module of optical relay

P2: output module of optical relay

1: si substrate

2：N-GaN

3：MQWS

4：P-GaN

5: p electrode

6: substrate

7: n electrode

8: p electrode

9：SiO₂

10：ITO

11：P-GaN

12：MQWs

13：N-GaN

14：i-GaN

15: substrate

16: n electrode

17: p electrode

18：ITO

19: upper confinement layer of P-GaN

20：i-GaN

21：N-GaN

22：i-GaN

23: substrate

24: n electrode

25: source metal

26：Si₃N₄Passivation layer

27: grid metal

28: drain metal

29: AlGaN buffer layer

30: i-GaN transition layer

31: GaN low temperature layer

32: si substrate

Detailed Description

The following describes in more detail a specific embodiment of the present invention with reference to the accompanying drawings. It is to be noted that the drawings are in simplified schematic form and are not to precise scale, which is only used for the purpose of convenience and clarity to assist in explaining the present invention.

An optical relay based on gallium nitride material comprises more than one light-emitting device, more than one photoelectric conversion device and more than two high electron mobility transistors; the light-emitting device, the photoelectric conversion device and the high electron mobility transistor are all prepared by growing gallium nitride materials; carrying out COB (chip on Board) packaging on the light-emitting device and the photoelectric conversion device chip, and enabling the light-emitting device to face the photoelectric conversion device; or encapsulating the light emitting device and the photoelectric conversion device in a transparent encapsulating layer having a highly reflective coating on the surface; the light emitting device is connected to the input end of the optical relay, the output end of the photoelectric conversion device is connected with the input ends of the high electron mobility transistors, namely the grid and the source, the sources of the two high electron mobility transistors are connected, and the drains of the two high electron mobility transistors are connected to the output end of the optical relay.

Embodiment mode 1

The GaN optical relay of embodiment 1 is, as shown in fig. 7, characterized in that the light emitting device, the photoelectric conversion device, and the output portion of the two HEMT devices are all epitaxial-grown and chip-fabricated using GaN materials, and the three devices are grown independently of each other to fabricate three independent chips, and then packaged and integrated. The light emitting element is fixed on the lead frame at the upper half part of the packaging structure, and the light emitting surface of the light emitting element is opposite to the light receiving surface of the light receiving element. The structural diagrams of the three devices correspond to fig. 3, 4 and 6, respectively.

Embodiment mode 2

The GaN optical relay of embodiment 2 is characterized in that the GaN light emitting device and the GaN photoelectric conversion device are integrated on the same substrate (the photoelectric relay structure is shown in fig. 8), and then packaged and integrated with the GaN HEMT chip of the output portion.

Embodiment 3

The GaN optical relay of embodiment 3 is characterized in that a GaN light emitting device, a GaN photoelectric conversion device, and a GaN HEMT device of an output portion are integrated on the same Si substrate, wherein the GaN light emitting device and the GaN photoelectric conversion device are each packaged by COB (photoelectric relay structure shown in fig. 9), or a GaN light emitting device chip and a GaN photoelectric conversion device chip are packaged in a transparent packaging layer, and a highly reflective coating is coated thereon (photoelectric relay structure shown in fig. 10), and the entire GaN optical relay is packaged and integrated on the same substrate.

As described above, for the specific embodiments of the present invention, it is obvious to those skilled in the art that the present invention can be modified and modified without departing from the core idea of the present invention, and the modified and modified embodiments also fall within the protection scope of the claims of the present invention.