CN111403479B - HEMT devices with multi-metal gate structures and their fabrication methods - Google Patents
HEMT devices with multi-metal gate structures and their fabrication methodsInfo
- Publication number
- CN111403479B CN111403479B CN202010204549.8A CN202010204549A CN111403479B CN 111403479 B CN111403479 B CN 111403479B CN 202010204549 A CN202010204549 A CN 202010204549A CN 111403479 B CN111403479 B CN 111403479B
- Authority
- CN
- China
- Prior art keywords
- metal
- gate
- layer
- gate electrode
- electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D30/00—Field-effect transistors [FET]
- H10D30/40—FETs having zero-dimensional [0D], one-dimensional [1D] or two-dimensional [2D] charge carrier gas channels
- H10D30/47—FETs having zero-dimensional [0D], one-dimensional [1D] or two-dimensional [2D] charge carrier gas channels having 2D charge carrier gas channels, e.g. nanoribbon FETs or high electron mobility transistors [HEMT]
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D30/00—Field-effect transistors [FET]
- H10D30/01—Manufacture or treatment
- H10D30/015—Manufacture or treatment of FETs having heterojunction interface channels or heterojunction gate electrodes, e.g. HEMT
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D30/00—Field-effect transistors [FET]
- H10D30/60—Insulated-gate field-effect transistors [IGFET]
- H10D30/67—Thin-film transistors [TFT]
- H10D30/6729—Thin-film transistors [TFT] characterised by the electrodes
- H10D30/6737—Thin-film transistors [TFT] characterised by the electrodes characterised by the electrode materials
- H10D30/6738—Schottky barrier electrodes
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D30/00—Field-effect transistors [FET]
- H10D30/60—Insulated-gate field-effect transistors [IGFET]
- H10D30/67—Thin-film transistors [TFT]
- H10D30/674—Thin-film transistors [TFT] characterised by the active materials
- H10D30/675—Group III-V materials, Group II-VI materials, Group IV-VI materials, selenium or tellurium
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D62/00—Semiconductor bodies, or regions thereof, of devices having potential barriers
- H10D62/80—Semiconductor bodies, or regions thereof, of devices having potential barriers characterised by the materials
- H10D62/85—Semiconductor bodies, or regions thereof, of devices having potential barriers characterised by the materials being Group III-V materials, e.g. GaAs
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D64/00—Electrodes of devices having potential barriers
- H10D64/20—Electrodes characterised by their shapes, relative sizes or dispositions
- H10D64/27—Electrodes not carrying the current to be rectified, amplified, oscillated or switched, e.g. gates
- H10D64/311—Gate electrodes for field-effect devices
- H10D64/411—Gate electrodes for field-effect devices for FETs
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D64/00—Electrodes of devices having potential barriers
- H10D64/60—Electrodes characterised by their materials
- H10D64/64—Electrodes comprising a Schottky barrier to a semiconductor
Landscapes
- Junction Field-Effect Transistors (AREA)
Abstract
The invention discloses a HEMT device with a multi-metal gate structure and a preparation method thereof. The device comprises AlGaN/GaN epitaxy, two ends of the upper surface of the AlGaN/GaN epitaxy are respectively connected with a source electrode and a drain electrode, a gate electrode is arranged on the source electrode and the drain electrode near the source electrode side, a first layer of metal X of the gate electrode is deposited in an electron beam evaporation mode, a second layer of metal Y of the gate electrode is deposited in a magnetron sputtering mode, the work function of the second layer of metal Y of the gate electrode is higher than that of the first layer of metal X, photoetching is not needed, and a metal structure contacted with (Al) GaN formed after the stripping of the gate electrode is Y/X/Y. The multi-metal gate structure is contacted with (Al) GaN, so that an electric field is redistributed, an electric field peak value of a gate edge close to a drain electrode is reduced, breakdown voltage of the device is improved, and meanwhile, a lower electric field peak value of the gate edge weakens electrons injected into the gate to form a virtual gate effect, current collapse of the device is reduced, and dynamic performance of the device is improved.
Description
Technical Field
The invention relates to the field of semiconductors, in particular to a HEMT device with a multi-metal gate structure and a preparation method thereof.
Background
GaN materials are widely used in high-frequency power amplifiers, high-voltage power switches and other occasions because of the characteristics of high electron mobility, low on-resistance, excellent heat dissipation capability, high breakdown and the like. The breakdown voltage of the current GaN-based HEMT device is far from reaching the theoretical limit value (3.4 MV/cm) of GaN materials, the device is easy to break down between gate and drain, and how to reduce the high electric field peak value near the gate edge at one side of the drain is beneficial to improving the breakdown voltage of the device. The most common approach is to use a gate field plate or source field plate to adjust the electric field distribution so as to reduce the high electric field peaks near the gate edge on the drain side. On the other hand, the virtual gate effect due to gate injection electrons exacerbates the impact on device current collapse, making the device exhibit poor performance under stress conditions. Passivation processes are commonly used to reduce the surface state on barrier layers, suppress current collapse (r.hao, et al, IEEE Electron Device lett.,2017, 38 (11)), and field plate processes are used to modulate the electric field, thereby reducing the surface state (h. Hanawa, et al, IEEE International Reliability Physics Symposium proceedings, 2013). A scholars (a.k. VISVKARMA, et Al, semiconductor, sci. technology, 2019, 34 (10)) realizes a double-layer gate metal process by changing the angle of electron beam deposition, forms a double-contact interface of a Ni/(Al) GaN gate and a Ti/(Al) GaN gate, changes the electric field distribution of the gate edge, and improves the breakdown voltage and the dynamic performance of the device.
Current devices for depositing metals are typically electron beam evaporation or magnetron sputtering. The magnetron sputtering device mainly uses argon ions to bombard the target material to sputter atoms of the material to the surface of the wafer, and the electron beam evaporation device mainly uses heating to melt the material, and after the material reaches the boiling point, particles of the material are separated from the surface of the material one by one to reach the surface of the wafer. For magnetron sputtering equipment, the sputtering distance is short, mainly related to collision among particles, and an average free path of particle movement is considered, similar to a point light source, and the angles among the particles are large, so that the area of the material sputtered on the surface of the wafer is larger than a defined photoetching window, while the cavity for electron beam evaporation is long, similar to a parallel light source, and the metal material is evaporated vertically on the surface of the wafer.
In summary, the dual-layer gate metal process helps to improve the breakdown voltage and dynamic performance of the device. However, the above-mentioned method of changing the angle of the electron beam deposition is difficult to control precisely and has poor reproducibility.
Disclosure of Invention
The HEMT device with the multi-metal gate structure is provided, a first layer metal X prepared by utilizing an electron beam is completely wrapped by a second layer metal Y prepared by utilizing magnetron sputtering, a YXY metal gate structure is formed, electric field distribution is regulated, electric field peaks near the gate edge of a drain electrode are reduced, breakdown voltage of the device is improved, and meanwhile, the influence of grid injection electrons on current collapse of the device by a grid electrode is weakened by the lower electric field peaks near the gate edge, and dynamic performance of the device is improved.
The object of the invention is achieved by at least one of the following technical solutions.
The invention provides a HEMT device with a multi-metal gate structure, which comprises AlGaN/GaN epitaxy, wherein two ends of the upper surface of the AlGaN/GaN epitaxy are respectively connected with source and drain electrodes, the source and drain electrodes are close to a source side and are provided with gate electrodes, a first layer of metal X of the gate electrodes is deposited in an electron beam evaporation mode, a second layer of metal Y of the gate electrodes is deposited in a magnetron sputtering mode, the work function of the second layer of metal Y of the gate electrodes is higher than that of the first layer of metal X, no extra photoetching step is needed, and the metal structure contacted with (Al) GaN formed after the stripping of the gate electrodes is Y/X/Y.
The invention adopts a method combining electron beam and magnetron sputtering, realizes the multi-metal gate structure Y/X/Y after metal stripping, does not need to change the angle of electron beam deposition, only adopts a traditional deposition mode for electron beam and magnetron sputtering, has repeatability, and compared with the double-layer gate metal process, the method based on the invention realizes the three-layer gate metal process.
The HEMT device with the multi-metal gate structure comprises an AlGaN/GaN epitaxy, a source electrode, a drain electrode and a gate electrode, wherein two ends of the upper surface of the AlGaN/GaN epitaxy are respectively connected with the source electrode and the drain electrode, the gate electrode is connected with the upper surface of the AlGaN/GaN epitaxy and comprises a first layer of metal X and a second layer of metal Y, and the metal structure contacted with (Al) GaN formed after the gate electrode is stripped is Y/X/Y.
The HEMT device with the multi-metal gate structure provided by the invention is an AlGaN/GaN HEMT device.
Further, the length of the second layer metal Y at two sides of the first layer metal X is 0.5-1 mu m.
Further, the two layers of metal Y completely encapsulate the first layer of metal X.
Further, the gate electrode to source distance is smaller than the gate electrode to drain distance, i.e. the source drain electrode is arranged close to the source side.
The invention provides a method for preparing the HEMT device with the multi-metal gate structure, which comprises the following steps:
(1) Defining a source-drain electrode window on AlGaN/GaN epitaxy, preparing a source-drain electrode and annealing to form ohmic contact;
(2) Defining a gate electrode photoetching window, and preparing a multi-metal gate structure Y/X/Y to obtain the HEMT device with the multi-metal gate structure.
Further, the photoetching window of the gate electrode in the step (2) is designed to be 1-2 mu m.
Further, in the step (2) of the multi-metal gate structure Y/X/Y, the first layer of metal X is deposited by electron beam evaporation, the second layer of metal Y is deposited by magnetron sputtering, and the thickness of the second layer of metal Y is greater than that of the first layer of metal X.
Further, in the multi-metal gate structure Y/X/Y in the step (2), the first metal layer X is one of Ni, ti, tiN and the second metal layer Y is one of Cu, W, ni and the like.
Compared with the prior art, the invention has the following beneficial effects and advantages:
The multi-metal grid electrode prepared by utilizing the electron beam and the magnetron sputtering does not need an extra photoetching step, the second metal Y prepared by the magnetron sputtering completely wraps the first metal X prepared by the electron beam, a multi-metal grid structure Y/X/Y is formed, electric field distribution is regulated, an electric field peak value near the grid edge of a drain electrode is reduced, breakdown voltage of a device is improved, meanwhile, a virtual grid effect formed by electron injection of the grid electrode is weakened by the lower electric field peak value at the grid edge, and by testing C-V characteristics, the saturation capacitance (158 pF) of the device of a corresponding W/TiN/W structure is reduced by 13.9% compared with the device (136 pF) of the TiN structure at the test frequency of 10KHz, and the dynamic performance of the device is improved.
Drawings
Fig. 1 is a schematic diagram of an epitaxial layer of a GaN-based HEMT device prior to fabrication of source-drain contact electrodes in an embodiment;
FIG. 2 is a schematic diagram of an embodiment device structure after source-drain electrodes are fabricated and annealed to form ohmic contacts;
FIG. 3 is a schematic view of a device structure after forming a gate electrode according to an embodiment;
fig. 4 is a capacitance data diagram of a HEMT device with a multi-metal gate structure and a TiN structure device prepared in example 2;
In the figure, alGaN/GaN is epitaxially grown on 1, source/drain electrode 2, and gate electrode 3.
Detailed Description
The following examples are presented to further illustrate the practice of the invention, but are not intended to limit the practice and protection of the invention. It should be noted that the following processes, if not specifically described in detail, can be realized or understood by those skilled in the art with reference to the prior art.
Example 1
The embodiment provides a HEMT device with a multi-metal gate structure, as shown in fig. 3, the device comprises an AlGaN/GaN epitaxy 1, two ends of the upper surface of the AlGaN/GaN epitaxy are respectively connected with a source-drain electrode 2, the source-drain electrode 2 is close to a source side and provided with a gate electrode 3, a first layer of metal Ti of the gate electrode 3 is deposited in an electron beam evaporation mode, a second layer of metal Ni of the gate electrode 3 is deposited in a magnetron sputtering mode, no extra photolithography step is needed, and a metal structure which is formed after the gate electrode 3 is stripped and is in contact with (Al) GaN is Ni/Ti/Ni. G-1 in FIG. 3 represents a first layer of metal and G-2 represents a second layer of metal.
The embodiment also provides a method for preparing the HEMT device with the multi-metal gate structure, which comprises the following steps:
(1) Defining a source-drain electrode window on AlGaN/GaN epitaxy (an epitaxial layer before preparing a source-drain contact electrode is shown in figure 1), preparing a source-drain electrode 2 and annealing to form ohmic contact, as shown in figure 2;
(2) Defining a gate electrode 3 photoetching window to prepare a multi-metal gate structure Ni/Ti/Ni, as shown in fig. 3, wherein the gate photoetching window of the HEMT device is designed to be 1 mu m, the length of a second layer of metal Ni on two sides of a first layer of metal Ti is 0.7 mu m, the thickness of the first layer of metal Ti is 50nm, the thickness of the second layer of metal Ni is 250nm, and the second layer of metal Ni completely wraps the first layer of metal Ti, so that the HEMT device with the multi-metal gate structure is obtained.
The HEMT device with the multi-metal gate structure prepared in embodiment 1 has good dynamic performance and low saturation capacitance, and can be shown by referring to fig. 4.
Example 2
The embodiment provides a HEMT device with a multi-metal gate structure, as shown in fig. 3, the device comprises an AlGaN/GaN epitaxy 1, two ends of the upper surface of the AlGaN/GaN epitaxy are respectively connected with a source-drain electrode 2, the source-drain electrode 2 is close to a source side and provided with a gate electrode 3, a first layer of metal TiN of the gate electrode 3 is deposited in an electron beam evaporation mode, a second layer of metal W of the gate electrode 3 is deposited in a magnetron sputtering mode, no extra photolithography step is needed, and a metal structure which is formed after the gate electrode 3 is stripped and is in contact with (Al) GaN is W/TiN/W.
The embodiment also provides a method for preparing the HEMT device with the multi-metal gate structure, which comprises the following steps:
(1) Defining a source-drain electrode window on AlGaN/GaN epitaxy 1, preparing a source-drain electrode 2 and annealing to form ohmic contact, as shown in figure 2;
(2) Defining a gate electrode 3 photoetching window to prepare a multi-metal gate structure W/TiN/W, as shown in figure 3, wherein the gate photoetching window of the HEMT device is designed to be 1 mu m, in the metal structure W/TiN/W formed after stripping of the gate electrode, the length of a second layer of metal W on two sides of a first layer of metal TiN is 0.5 mu m, the thickness of the first layer of metal TiN is 50nm, the thickness of the second layer of metal W is 200nm, and the second layer of metal W completely wraps the first layer of metal TiN, so that the HEMT device with the multi-metal gate structure is obtained.
Fig. 4 is a C-V characteristic comparison chart of the HEMT device (W/TiN/W) with the multi-metal gate structure prepared in example 2, only showing the corresponding capacitance data at the test frequency of 10KHz, and it can be seen that the device with the W/TiN/W structure has a lower saturation capacitance value than the device with the TiN structure.
The above examples are only preferred embodiments of the present invention, and are merely for illustrating the present invention, not for limiting the present invention, and those skilled in the art should not be able to make any changes, substitutions, modifications and the like without departing from the spirit of the present invention.
Claims (2)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010204549.8A CN111403479B (en) | 2020-03-21 | 2020-03-21 | HEMT devices with multi-metal gate structures and their fabrication methods |
| PCT/CN2020/132690 WO2021189923A1 (en) | 2020-03-21 | 2020-11-30 | Hemt device having multi-metal gate structure and fabrication method therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010204549.8A CN111403479B (en) | 2020-03-21 | 2020-03-21 | HEMT devices with multi-metal gate structures and their fabrication methods |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111403479A CN111403479A (en) | 2020-07-10 |
| CN111403479B true CN111403479B (en) | 2025-11-25 |
Family
ID=71413951
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010204549.8A Active CN111403479B (en) | 2020-03-21 | 2020-03-21 | HEMT devices with multi-metal gate structures and their fabrication methods |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN111403479B (en) |
| WO (1) | WO2021189923A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111403479B (en) * | 2020-03-21 | 2025-11-25 | 中山市华南理工大学现代产业技术研究院 | HEMT devices with multi-metal gate structures and their fabrication methods |
| CN113725287B (en) * | 2021-07-21 | 2023-05-05 | 中山市华南理工大学现代产业技术研究院 | Low-temperature gold-free ohmic contact GaN-based HEMT device and preparation method thereof |
| CN114927566B (en) * | 2022-02-18 | 2025-07-25 | 中山市华南理工大学现代产业技术研究院 | GaN-based HEMT gold-free ohmic contact electrode based on Ti/Al/Ni/Cu and preparation method thereof |
| CN116072714A (en) * | 2022-12-09 | 2023-05-05 | 重庆邮电大学 | HEMT device with integrated gate electrode structure and its preparation method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108604596A (en) * | 2015-07-17 | 2018-09-28 | 剑桥电子有限公司 | Field plate structure for semiconductor device |
| CN212907750U (en) * | 2020-03-21 | 2021-04-06 | 中山市华南理工大学现代产业技术研究院 | HEMT device with multi-metal gate structure |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8318562B2 (en) * | 2007-04-02 | 2012-11-27 | University Of South Carolina | Method to increase breakdown voltage of semiconductor devices |
| CN101881667B (en) * | 2010-06-24 | 2015-09-09 | 电子科技大学 | A kind of uncooled microbolometer and preparation method thereof |
| CN104377241B (en) * | 2014-09-30 | 2017-05-03 | 苏州捷芯威半导体有限公司 | Power semiconductor device and manufacturing method thereof |
| CN106158948B (en) * | 2015-04-10 | 2020-05-19 | 中国科学院苏州纳米技术与纳米仿生研究所 | III-nitride enhanced HEMT device and manufacturing method thereof |
| CN104966731B (en) * | 2015-07-06 | 2018-04-10 | 大连理工大学 | HEMT device with sandwich gate dielectric structure and preparation method thereof |
| CN107799590B (en) * | 2017-11-21 | 2024-05-24 | 华南理工大学 | A GaN-based microwave power device with large gate width and a manufacturing method thereof |
| JP6997002B2 (en) * | 2018-02-19 | 2022-01-17 | 住友電気工業株式会社 | Semiconductor devices and their manufacturing methods |
| CN109037050B (en) * | 2018-07-17 | 2021-09-17 | 中山市华南理工大学现代产业技术研究院 | Preparation method of GaN-based HEMT gold-free ohmic contact electrode based on TiN |
| CN111403479B (en) * | 2020-03-21 | 2025-11-25 | 中山市华南理工大学现代产业技术研究院 | HEMT devices with multi-metal gate structures and their fabrication methods |
-
2020
- 2020-03-21 CN CN202010204549.8A patent/CN111403479B/en active Active
- 2020-11-30 WO PCT/CN2020/132690 patent/WO2021189923A1/en not_active Ceased
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108604596A (en) * | 2015-07-17 | 2018-09-28 | 剑桥电子有限公司 | Field plate structure for semiconductor device |
| CN212907750U (en) * | 2020-03-21 | 2021-04-06 | 中山市华南理工大学现代产业技术研究院 | HEMT device with multi-metal gate structure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111403479A (en) | 2020-07-10 |
| WO2021189923A1 (en) | 2021-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111403479B (en) | HEMT devices with multi-metal gate structures and their fabrication methods | |
| JP2019517734A (en) | Multi-step surface passivation structure and method for manufacturing the same | |
| CN111223933A (en) | Novel epitaxial layer structure for improving threshold voltage of GaN enhanced MOSFET | |
| CN102386223A (en) | High-threshold voltage gallium nitride (GaN) enhancement metal oxide semiconductor heterostructure field effect transistor (MOSHFET) device and manufacturing method | |
| CN109560120B (en) | GaN normally-off MISFET device with vertical grooves grown in selective area and manufacturing method thereof | |
| CN107768252A (en) | A kind of normally-off GaN base MOSFET structure of the high conduction property of high threshold voltage and preparation method thereof | |
| CN107706241A (en) | A kind of normally-off GaNMOSFET structures at high quality MOS interfaces and preparation method thereof | |
| CN111403480A (en) | High-voltage AlGaN/GaN HEMT device and preparation method thereof | |
| CN113725287B (en) | Low-temperature gold-free ohmic contact GaN-based HEMT device and preparation method thereof | |
| CN114664938A (en) | A kind of GaN-based HEMT device and its preparation method and application | |
| CN107154426A (en) | A kind of device architecture and implementation method for improving silicon substrate GaN HEMT breakdown voltages | |
| CN114122127B (en) | A nitride HEMT device with combined passivation medium and its preparation method | |
| CN108598154A (en) | Enhanced gallium nitride transistor and preparation method thereof | |
| CN117423725A (en) | High-voltage transverse GaN high-electron mobility transistor | |
| CN104701363B (en) | A kind of transistor and preparation method thereof based on enhanced grid structure | |
| CN107706232A (en) | A kind of MIS grid structure normally-off GaN base transistor in situ and preparation method | |
| CN105679679B (en) | A kind of preparation method of GaN base notched gates MISFET | |
| CN212907750U (en) | HEMT device with multi-metal gate structure | |
| CN216250739U (en) | Gallium nitride transistor with high conduction capability | |
| CN109755301B (en) | A GaN MISFET device with high-quality gate interface and its preparation method | |
| CN111430459B (en) | AlGaAs/GaAs high electron mobility transistor and preparation method | |
| CN209487514U (en) | A GaN MISFET device with high-quality gate interface | |
| CN115966604B (en) | A semiconductor device structure and its fabrication method | |
| CN207966998U (en) | A kind of normally-off GaN base MOSFET structure of the high conduction property of high threshold voltage | |
| CN214378453U (en) | NiO is containedXMIS-HEMT device of protective layer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |