CN211743090U - Power device - Google Patents
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- CN211743090U CN211743090U CN202020537935.4U CN202020537935U CN211743090U CN 211743090 U CN211743090 U CN 211743090U CN 202020537935 U CN202020537935 U CN 202020537935U CN 211743090 U CN211743090 U CN 211743090U
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Abstract
The utility model discloses a power device, which comprises at least one vacuum-packaged unit structure; wherein the unit structure includes: the light modulator comprises a silicon substrate, and an emitter, a light modulator and a collector which are formed on the silicon substrate. On one hand, the whole device is prepared by adopting a uniform silicon-based process, so that the problem of inconsistency of an emitting electrode of the traditional cold cathode field emission in the process of preparation is solved, the internal precision and consistency of the device are improved, and the reliability of the device is enhanced; on the other hand, the light modulation electrode formed on the silicon substrate is introduced based on a silicon-based process, so that the field emission efficiency of the emitter is enhanced, the inconsistency of the distance between the tip of the emitter and the collector caused by the nonuniformity of the emitter is offset, the process redundancy of the cold cathode emission electrode is increased, the device does not need to generate electrons completely by depending on a field emission principle, the load of field emission is reduced, and the reliability of the device is further enhanced.
Description
Technical Field
The utility model relates to a vacuum microelectronics technical field especially relates to a power device.
Background
The withstand voltage of the existing power device is born by a space electric field of a semiconductor junction, and the on-resistance and the working efficiency of the device are limited. The existing vacuum microelectronic power device with field cathode emission can improve the voltage endurance of the power device, but the electron emission is completely emitted by the electric field, so the power and reliability of the device are not guaranteed, and the product is not mature.
SUMMERY OF THE UTILITY MODEL
The embodiment of the application provides a power device, and solves the technical problem that an existing power device is low in reliability.
The application provides the following technical scheme through an embodiment of the application:
a power device includes at least one vacuum-packed cell structure; wherein the unit structure includes:
a silicon substrate;
an emitter formed on the silicon substrate by a silicon-based process;
a light modulation electrode formed on the silicon substrate by a silicon-based process, the light modulation electrode being used for generating photons to excite the emitter to emit electrons;
and a collector formed on the silicon substrate by using a silicon-based process, wherein the collector is used for exciting the electrons emitted by the emitter.
Optionally, the unit structure further includes:
and a grid electrode formed on the silicon substrate by utilizing a silicon-based process, wherein the grid electrode is used for generating an electric field to excite the emitter to emit electrons.
Optionally, the light modulator is an LED structure emitting light laterally.
Optionally, the light modulator is an ultraviolet LED.
Optionally, the ultraviolet LED includes an N-type semiconductor material, a P-type semiconductor material, and a resonant cavity formed by the N-type semiconductor material and the P-type semiconductor material.
Optionally, the N-type semiconductor material and the P-type semiconductor material are gallium nitride, indium gallium nitride, or aluminum gallium nitride.
Optionally, the emitter includes a silicon-based microtip structure and a metal layer covering the silicon-based microtip structure.
Optionally, the pressure of the vacuum packaging is 10-6Pa～10Pa。
Optionally, the power device includes at least two of the cell structures, and the two cell structures are image-integrated along the light modulation electrode.
Optionally, a bonding cover plate is further formed on the two unit structures integrated along the mirror image of the light modulation electrode.
One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:
a vacuum-encapsulated cell structure for a power device, comprising: a silicon substrate; an emitter formed on the silicon substrate by a silicon-based process; a light modulation electrode formed on the silicon substrate by a silicon-based process, the light modulation electrode being used for generating photons to excite the emitter to emit electrons; and a collector formed on the silicon substrate by using a silicon-based process, wherein the collector is used for exciting the electrons emitted by the emitter. On one hand, the whole device is prepared by adopting a uniform silicon-based process, so that the problem of inconsistency of an emitting electrode of the traditional cold cathode field emission in the process of preparation is solved, the internal precision and consistency of the device are improved, and the reliability of the device is enhanced; on the other hand, the light modulation electrode formed on the silicon substrate is introduced based on a silicon-based process, so that the field emission efficiency of the emitter is enhanced, the inconsistency of the distance between the tip of the emitter and the collector caused by the nonuniformity of the emitter is offset, the process redundancy of the cold cathode emission electrode is increased, the device does not need to generate electrons completely by depending on a field emission principle, the load of field emission is reduced, and the reliability of the device is further enhanced.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic diagram of a cell structure of a power device according to an embodiment of the present invention;
fig. 2 is a schematic diagram of another unit structure of a power device according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of the emitter structure of FIG. 1;
fig. 4 is a schematic structural diagram of a power device according to an embodiment of the present invention.
The reference numerals are explained below:
100. the silicon substrate, 200, an emitter, 210, a silicon-based micro-tip structure, 220, a metal layer, 300, a light modulation electrode, 400, a collector, 500, a grid, 600 and a bonding cover plate.
Detailed Description
The embodiment of the application provides a power device, and solves the technical problem that an existing power device is low in reliability.
In order to solve the technical problems, the general idea of the embodiment of the application is as follows:
a power device includes at least one vacuum-packed cell structure; wherein the unit structure includes: a silicon substrate 100; an emitter 200 formed on the silicon substrate 100 using a silicon-based process; an optical modulator 300 formed on the silicon substrate 100 by a silicon-based process, the optical modulator 300 being configured to generate photons to excite the emitter 200 to emit electrons; a collector 400 formed on the silicon substrate 100 using a silicon-based process, the collector 400 for exciting the electron emitted from the emitter 200.
On one hand, the whole device is prepared by adopting a uniform silicon-based process, so that the problem of inconsistency of the emitter 200 of the traditional cold cathode field emission in the process of preparation is solved, the internal precision and consistency of the device are improved, and the reliability of the device is enhanced; on the other hand, the light modulation electrode 300 formed on the silicon substrate 100 is introduced based on a silicon-based process, so that the field emission efficiency of the emitter 200 is enhanced, the inconsistency of the distance between the tip of the emitter 200 and the collector 400 caused by the nonuniformity of the emitter 200 is counteracted, the process redundancy of the cold cathode emission electrode is increased, the device does not need to generate electrons completely by depending on the field emission principle, the load of field emission is reduced, and the reliability of the device is further enhanced.
In order to better understand the technical solution, the technical solution will be described in detail with reference to the drawings and the specific embodiments.
First, it is stated that the term "and/or" appearing herein is merely one type of associative relationship that describes an associated object, meaning that three types of relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
Also, the appearances of the phrases "in" and "out" in this document are not necessarily all referring to the same embodiment, but are to be construed broadly and encompass both forms.
Analysis of the prior art shows that the conventional power device bears bias voltage by means of PN, and the large bias voltage requires a large drift region, which increases on-resistance and affects the operating efficiency of the device. Therefore, the cathode field emission principle is used to improve the voltage endurance of the power device, but the cathode field emission array cannot realize a uniform field emission threshold due to the process inconsistency in the process of processing, thereby affecting the power improvement and the long-term working reliability of the whole device. Therefore, it is attempted to increase the field emission efficiency by using the optical modulation principle and increase the threshold margin of the field emission, but the existing optical modulation methods all use the technologies such as optical fiber and carbon nanotube to introduce the external light source, and the integration and the modulation performance are greatly affected, so that the possibility of mass production is not provided.
As shown in fig. 1, the present application provides, by one embodiment, a power device including at least one vacuum-packed cell structure; wherein the unit structure includes:
a silicon substrate 100;
an emitter 200 formed on the silicon substrate 100 using a silicon-based process;
an optical modulator 300 formed on the silicon substrate 100 by a silicon-based process, the optical modulator 300 being configured to generate photons to excite the emitter 200 to emit electrons;
a collector 400 formed on the silicon substrate 100 using a silicon-based process, the collector 400 for exciting the electron emitted from the emitter 200.
It should be noted that the power device of the present embodiment generally includes a plurality of unit structures integrated together, and the internal structure of a single unit structure is described first.
Referring to fig. 1, a silicon substrate 100 is positioned at the bottom, and an emitter 200, a collector 400, and a light modulation electrode 300 are formed on the silicon substrate 100 using a silicon-based process. On one hand, due to the adoption of the uniform silicon-based process, the problem of inconsistency of the emitter 200 of the traditional cold cathode field emission in the process of preparation is solved, the internal precision and consistency of the device are improved, and the reliability of the device is enhanced. On the other hand, in operation, the emitter 200 and the collector 400 excite the emitter 200 to emit electrons through the electric field effect, and the collector 400 receives the electrons; meanwhile, the light modulation electrode 300 excites the emitter 200 to emit electrons through a photoelectric effect to supplement an electric field effect, so that the device does not need to generate electrons completely by depending on a field emission principle, the process redundancy of the cold cathode emission electrode is increased, the load of field emission is reduced, and the reliability of the device is enhanced. In addition, since the optical modulation electrode 300 applies optical modulation, the modulation frequency is increased, and high-frequency response, even high-frequency high-power response, can be realized.
In addition, the complementary effect of the optical modulator 300 on field emission through the photoelectric effect can also increase the margin of the field emission threshold, so that the field emission array can still normally work under the assistance of light under the condition of non-uniform emission threshold, the array integration of a unit structure is facilitated, and the power of the device and the reliability of long-term work are further improved. The light modulation electrode 300 is formed on the silicon substrate 100 by a silicon-based process, so that self-luminescence can be realized, external light sources are not required to be introduced by external optical fibers or carbon nanotubes and other technologies, and necessary conditions for large-scale integration are formed.
As an alternative structure, referring to fig. 2, the unit structure further includes: a gate 500 formed on the silicon substrate 100 using a silicon-based process, the gate 500 for generating an electric field to excite the emitter 200 to emit electrons.
In this structure, the gate electrode 500 is positioned between the collector electrode 400 and the emitter electrode 200 for generating an electric field to excite the emitter electrode 200 to emit electrons, and the collector electrode 400 is for receiving electrons. The benefits of adding gate 500 are: the field emission modulation efficiency is increased, and the device can realize an electric modulation electrode which is complementary with the light modulation by increasing the modulation electric field by using the grid 500 which is closer to the emitter besides the collector 400 to generate the field emission electric field. In addition, the control of the two modulation ends can increase the reliability of the device, so that the two control parameters do not need to work under extreme conditions.
It should be noted that when the gate 500 is present, the photoelectric effect is compensated by the non-uniformity of the pitch between the tip of the emitter 200 and the gate 500.
In this embodiment, the pressure of the vacuum package is 10-6Pa to 10Pa, and the reason for this setting range is: the electron of the device passes a certain distance from the emitter 200 to the collector 400, if the distance is full of air, the electron collides with gas atoms in the air, and the electron reaches the collector 400. therefore, the necessary vacuum condition is the requirement for ensuring the normal operation of the device, and the distance between the grid 500 and the emitter 200 or between the collector 400 and the emitter 200 is different according to the different processing technologies, so to reach the field emission electric field, the applied field emission voltage is proportional to the emission distance and inversely proportional to the pressure of the vacuum cavity, therefore, the pressure is in a certain range, and the lower limit of the air pressure is generally limited by the manufacturing process capabilityAnd the high voltage limit is determined by the reliability of the device, and the pressure can reach 10Pa at the maximum when the field emission voltage is lower than 30V and the emission efficiency is 1 percent.
After the overall structure of the cell structure is clarified, a specific structure of the light modulator 300 and the emitter 200 will be described below.
Referring to fig. 1 and 2, in the present embodiment, the light modulation electrode 300 is a lateral light emitting LED structure for transmitting photons to the emitter 200 located at the side. The type of the light source can be selected as required as long as the photoelectric effect can be generated and the emitter can be excited to emit electrons, for example, light-emitting LEDs with different wavelengths can be processed according to different metal types (different work functions) of the emitter 200; illustratively, the light modulator 300 is an ultraviolet LED. The shorter wavelength of the ultraviolet light can produce the photoelectric effect more effectively. Specifically, the ultraviolet LED includes an N-type semiconductor material, a P-type semiconductor material, and a resonant cavity formed by the N-type semiconductor material and the P-type semiconductor material. The semiconductor material for the light modulation electrode can be selected according to the requirement, and the InGaN/AlGaN structure is used, and the N-type semiconductor material and the P-type semiconductor material are gallium nitride, indium gallium nitride and aluminum gallium nitride. The reason for selecting gallium nitride, indium gallium nitride and aluminum gallium nitride is that the wide forbidden band width is favorable for forming ultraviolet light with shorter wavelength, the direct band gap is favorable for high light emission efficiency, and the structure and the process of the silicon-based gallium nitride LED are very mature.
In the specific implementation process, the ultraviolet LED can be LED out of the electrode, and the light intensity is controlled through voltage so as to supplement the field emission efficiency.
Referring to fig. 3, in the present embodiment, the emitter 200 includes a silicon-based microtip structure 210 and a metal layer 200 covering the silicon-based microtip structure 210. The metal layer 200 may be selected as desired, such as molybdenum. The metal layer 200 is attached to the silicon-based microtip structure 210 or is etched directly from the metal layer 200.
In this embodiment, the silicon-based process refers to a standard processing and manufacturing process using a silicon wafer as a substrate. In a specific implementation process, the unit structure of this embodiment may be specifically prepared by the following method:
1. extending a gallium nitride material on a silicon substrate 100 to prepare a light-emitting diode, wherein the cathode of the light-emitting diode is connected with the substrate, and the anode of the light-emitting diode is led out to be used as a light modulation electrode of a power device;
2. manufacturing a molybdenum-tipped emitter beside the light-emitting diode by using a Spindt method, or manufacturing a silicon-tipped emitter 200 by using an oxidation sharpening process, wherein the emitter 200 is partially connected with the silicon substrate 100 to jointly form an emitting structure of a device;
3. evaporating metal on another silicon substrate to form a collector 400;
4. the collector 400 and other prepared parts are combined together in a vacuum environment through a silicon wafer bonding process to form a collector, and a bonding cover plate 600 in a vacuum environment is provided; the metal surface of the collector 400 is bonded to other parts, and the collector 400 can also be formed by bonding a silicon wafer without evaporated metal;
5. and leading out each electrode through a silicon processing technology for subsequent packaging.
After the specific construction of the single cell structure is clarified, the operation principle of the cell structure is explained as follows:
fig. 1 and fig. 2 are unit structures of two power devices, fig. 1 is a simplified structure of fig. 2, the modulator of fig. 1 only modulates light provided by the light modulator 300, a field emission electric field is provided by a collector 400, the electric field provided by the collector 400 satisfies the minimum field emission electric field condition in the device structure array, i.e. provides a base electric field, and then the device is excited by the light field provided by the light modulator 300 to assist the emitter electrons, the excited electrons are received by the collector 400, and the amount of the received electrons is modulated and controlled by the light modulator 300. Whereas the device of fig. 2 is modulated by the light modulation provided by the light modulating electrode 300 and the electric field provided by the gate 500, the collector 400 voltage in fig. 2 can be reduced appropriately according to circuit operating requirements, since the field emission electric field is no longer provided, or a higher collector voltage can be achieved by increasing the collector 400 to emitter 200 distance. In addition, the control of the two modulation ends can increase the reliability of the device, so that the two control parameters do not need to work under extreme conditions. The silicon substrate 100 and the emitter 200 are interconnected structures and are emitters (cathodes) of devices, the cathode of the light modulation electrode 300 is connected with the structures 100 and 200, and the anode of the light modulation electrode 300, namely the light modulation electrode, is led out independently. The collector 400 and the gate 500 are also separately led out to form the collector 400 or the electrical modulator, respectively.
As mentioned above, in the present embodiment, the power device generally includes a plurality of unit structures integrated together, and after the specific construction and operation principle of the single unit structure are clarified, an embodiment of the unit structure integration is provided below.
Referring to fig. 4, as an alternative embodiment, the power device includes at least two of the cell structures, and the two cell structures are image-integrated along the light modulation electrode 300. Specifically, a bonding cover plate 600 is further formed on two unit structures mirror-integrated along the light modulator 300. In the structure of fig. 4, the gate electrode 500 is not formed, and is directly integrated using the cell structure of fig. 1. After integration, the collector 400 generates a field emission electric field, the light modulator 300 forms a photoelectric modulator, and the variation of the collector current of the device is controlled by the photoelectric modulator. In addition, the array structure is favorable for forming a reproducible array structure and forming a device with high power. Therefore, referring to the integration manner of fig. 4, a plurality of unit structures can be integrated in an array manner, so that the power of the whole device is improved.
The technical scheme in the embodiment of the application at least has the following technical effects or advantages:
the power device of the present embodiment includes a vacuum-sealed unit structure including: a silicon substrate 100; an emitter 200 formed on the silicon substrate 100 using a silicon-based process; an optical modulator 300 formed on the silicon substrate 100 by a silicon-based process, the optical modulator 300 being configured to generate photons to excite the emitter 200 to emit electrons; a collector 400 formed on the silicon substrate 100 using a silicon-based process, the collector 400 for exciting the electron emitted from the emitter 200. On one hand, the whole device is prepared by adopting a uniform silicon-based process, so that the problem of inconsistency of the emitter 200 of the traditional cold cathode field emission in the process of preparation is solved, the internal precision and consistency of the device are improved, and the reliability of the device is enhanced; on the other hand, the light modulation electrode 300 formed on the silicon substrate 100 is introduced based on a silicon-based process, so that the field emission efficiency of the emitter 200 is enhanced, the inconsistency of the distance between the tip of the emitter 200 and the collector 400 caused by the nonuniformity of the emitter 200 is counteracted, the process redundancy of the cold cathode emission electrode is increased, the device does not need to generate electrons completely by depending on the field emission principle, the load of field emission is reduced, and the reliability of the device is further enhanced.
While the preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the appended claims be interpreted as including the preferred embodiment and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A power device comprising at least one vacuum-encapsulated cell structure; wherein the unit structure includes:
a silicon substrate;
an emitter formed on the silicon substrate by a silicon-based process;
a light modulation electrode formed on the silicon substrate by a silicon-based process, the light modulation electrode being used for generating photons to excite the emitter to emit electrons;
and a collector formed on the silicon substrate by using a silicon-based process, wherein the collector is used for exciting the electrons emitted by the emitter.
2. The power device of claim 1, wherein the cell structure further comprises:
and a grid electrode formed on the silicon substrate by utilizing a silicon-based process, wherein the grid electrode is used for generating an electric field to excite the emitter to emit electrons.
3. The power device of claim 1, wherein the light modulating electrode is an LED structure that emits light laterally.
4. The power device of claim 3, wherein the light modulating electrode is an ultraviolet LED.
5. The power device of claim 4, wherein the ultraviolet LED comprises an N-type semiconductor material, a P-type semiconductor material, and a resonant cavity formed by the N-type semiconductor material and the P-type semiconductor material.
6. The power device of claim 5, wherein the N-type and P-type semiconductor materials are gallium nitride, indium gallium nitride, or aluminum gallium nitride.
7. The power device of claim 1 wherein said emitter comprises a silicon-based microtip structure and a metal layer overlying said silicon-based microtip structure.
8. The power device of claim 1, wherein the vacuum package has a pressure of 10-6Pa～10Pa。
9. The power device according to any of claims 1-8, wherein said power device comprises at least two of said cell structures, both of said cell structures being image-integrated along said light modulating electrode.
10. The power device of claim 9, wherein a bonded cover plate is further formed over two of said cell structures mirror-integrated along said light modulator electrode.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020537935.4U CN211743090U (en) | 2020-04-13 | 2020-04-13 | Power device |
| PCT/CN2021/072889 WO2021208553A1 (en) | 2020-04-13 | 2021-01-20 | Power device and preparation method therefor |
| US17/595,770 US20220328275A1 (en) | 2020-04-13 | 2021-01-20 | Power device and fabrication method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020537935.4U CN211743090U (en) | 2020-04-13 | 2020-04-13 | Power device |
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| Publication Number | Publication Date |
|---|---|
| CN211743090U true CN211743090U (en) | 2020-10-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202020537935.4U Active CN211743090U (en) | 2020-04-13 | 2020-04-13 | Power device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111477527A (en) * | 2020-04-13 | 2020-07-31 | 中国科学院微电子研究所 | Power device and preparation method thereof |
| WO2021208553A1 (en) * | 2020-04-13 | 2021-10-21 | 中国科学院微电子研究所 | Power device and preparation method therefor |
-
2020
- 2020-04-13 CN CN202020537935.4U patent/CN211743090U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111477527A (en) * | 2020-04-13 | 2020-07-31 | 中国科学院微电子研究所 | Power device and preparation method thereof |
| WO2021208553A1 (en) * | 2020-04-13 | 2021-10-21 | 中国科学院微电子研究所 | Power device and preparation method therefor |
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