CN111129163A - Schottky diode and preparation method thereof - Google Patents
Schottky diode and preparation method thereof Download PDFInfo
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- CN111129163A CN111129163A CN201911231350.8A CN201911231350A CN111129163A CN 111129163 A CN111129163 A CN 111129163A CN 201911231350 A CN201911231350 A CN 201911231350A CN 111129163 A CN111129163 A CN 111129163A
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- H10D8/051—Manufacture or treatment of Schottky diodes
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Abstract
本发明涉及半导体领域，特别涉及一种肖特基二极管及其制备方法。该方法包括：在衬底上外延n型氧化镓层；在所述n型氧化镓层上制备第一掩膜层；其中，所述第一掩膜层的窗口为待制备的热氧化处理区所对应的区域，其中，所述热氧化处理区包括至少一个第一热氧化区和两个第二热氧化区；对器件正面进行第一高温退火处理，形成热氧化处理区；去除所述第一掩膜层；制备正面的阳极金属层和背面的阴极金属层；其中，所述第一热氧化区位于阳极金属下方，每个第二热氧化区部分位于阳极金属下方。上述方法可以通过热氧化形成终端结构，降低阳极金属下方及边缘区电场，从而降低阳极反向漏电，改善击穿和导通特性。
The invention relates to the field of semiconductors, in particular to a Schottky diode and a preparation method thereof. The method includes: epitaxially an n-type gallium oxide layer on a substrate; preparing a first mask layer on the n-type gallium oxide layer; wherein, a window of the first mask layer is a thermal oxidation treatment area to be prepared The corresponding area, wherein the thermal oxidation treatment area includes at least one first thermal oxidation area and two second thermal oxidation areas; a first high temperature annealing treatment is performed on the front side of the device to form a thermal oxidation treatment area; the first thermal oxidation treatment area is removed; A mask layer; preparing the anode metal layer on the front side and the cathode metal layer on the back side; wherein, the first thermal oxidation zone is located under the anode metal, and each second thermal oxidation zone is partially located under the anode metal. The above method can form a terminal structure through thermal oxidation, and reduce the electric field under the anode metal and in the edge region, thereby reducing the anode reverse leakage and improving the breakdown and conduction characteristics.
Description
Technical Field
The invention relates to the field of semiconductors, in particular to a Schottky diode and a preparation method thereof.
Background
As semiconductor devices are applied in more and more technical fields, conventional silicon-based and other narrow bandgap semiconductor diodes have many challenges, in which breakdown voltage is difficult to meet the increasing requirements, and becomes one of the key factors influencing further improvement of device performance. Gallium oxide (Ga)2O3) Compared with the third generation semiconductor material represented by SiC and GaN, the semiconductor material has wider forbidden band width, the breakdown field strength is more than 20 times that of Si and more than 2 times that of SiC and GaN, and theoretically, when a diode device with the same withstand voltage is manufactured, the on-resistance of the device can be reduced to 1/10 of SiC and 1/3 of GaN, and the on-resistance of the device can be reduced to Ga2O3The baliga figure of merit of the material is 18 times that of SiC and 4 times or more that of GaN material, so Ga2O3The semiconductor material is a wide bandgap semiconductor material with excellent performance and suitable for preparing power devices and high-voltage switching devices.
The wide bandgap gallium oxide Schottky diode has the advantages of high breakdown, low on-resistance and the like, and the Ga is improved at present2O3The performance of the schottky diode is continuously improved by methods such as crystal material quality and optimized doping process, however, the breakdown voltage and the conduction characteristic of the existing schottky diode are far lower than the expected value of the material.
Disclosure of Invention
In view of this, embodiments of the present invention provide a schottky diode and a method for manufacturing the schottky diode, so as to improve the breakdown voltage and the turn-on characteristic of the conventional schottky diode.
A first aspect of an embodiment of the present invention provides a method for manufacturing a schottky diode, including:
extending an n-type gallium oxide layer on a substrate;
preparing a first mask layer on the n-type gallium oxide layer; the window of the first mask layer is a region corresponding to a thermal oxidation treatment region to be prepared, and the thermal oxidation treatment region comprises at least one first thermal oxidation region and two second thermal oxidation regions;
carrying out first high-temperature annealing treatment on the front surface of the device to form a thermal oxidation treatment area;
removing the first mask layer;
preparing an anode metal layer on the front side and a cathode metal layer on the back side;
the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a first region, the region outside the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a second region, and the first thermal oxidation region is located in the first region; the first portion of each second thermal oxide region is located in the first region and the second portion of each second thermal oxide region is located in the second region.
Optionally, the thermal oxidation processing area further includes: and the third thermal oxidation area is positioned in the second area.
Optionally, after forming the thermal oxidation treatment zone, the method further comprises: and performing high temperature annealing treatment on at least one of the first thermal oxidation region, the second thermal oxidation region and the third thermal oxidation region.
Optionally, the substrate is an n-type gallium oxide substrate, and the doping concentration of the substrate is greater than that of the n-type gallium oxide layer.
Optionally, the n-type gallium oxide layer is non-uniformly doped, and the n-type gallium oxide layer has a multi-layer structure with increased concentration from top to bottom.
Optionally, the preparing the anode metal layer on the front surface includes:
after removing the first mask layer, depositing an insulating medium layer;
removing the insulating medium layer of the preset anode region by dry etching or wet etching;
preparing an anode metal layer with a front surface of a field plate structure; the field plate structure comprises a single-layer field plate structure, a multi-layer field plate structure and an inclined field plate structure;
correspondingly, the preset anode region is a first region, and the region outside the preset anode region is a second region.
A second aspect of an embodiment of the present invention provides a schottky diode, including:
a substrate;
an n-type gallium oxide layer formed on the substrate;
an anode metal layer formed on the n-type gallium oxide layer;
a cathode metal layer formed on the back surface of the substrate;
wherein, the n-type gallium oxide layer comprises: the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a first region, the region outside the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a second region, and the first thermal oxidation region is positioned in the first region and is in contact with the anode metal layer; the first portion of each second thermal oxidation region is located in the first region, the second portion of each second thermal oxidation region is located in the second region, and the first portion of each second thermal oxidation region is in contact with the anode metal layer.
Optionally, the n-type gallium oxide layer further includes: and the third thermal oxidation area is positioned in the second area, and the upper surface of the third thermal oxidation area is the upper surface of the n-type gallium oxide layer.
Optionally, the annealing temperature and the annealing time in the formation process of the first thermal oxidation region, the second thermal oxidation region and the third thermal oxidation region are different.
Optionally, the substrate is an n-type gallium oxide substrate, and the doping concentration of the substrate is greater than that of the n-type gallium oxide layer;
the n-type gallium oxide layer is non-uniformly doped, and the n-type gallium oxide layer is of a multi-layer structure with the concentration increased from top to bottom.
When the Schottky diode is prepared, the front surface of the device is subjected to high-temperature annealing treatment to form a thermal oxidation treatment area; the preparation of the first mask layer on the n-type gallium oxide layer can form a thermal oxidation treatment area at a specific position, wherein the thermal oxidation treatment area comprises at least one first thermal oxidation area located in the area below the anode metal layer and two second thermal oxidation areas partially located below the anode metal layer. After the first mask layer is removed, the anode metal layer is prepared at a specific position of the front side of the device, and the first thermal oxidation region and the second thermal oxidation region are arranged below the anode metal layer, so that electric fields below the anode metal layer and in a marginal region are reduced, reverse electric leakage of the anode metal layer is reduced, and breakdown voltage and conduction characteristics of the prepared Schottky diode are improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
Fig. 1 is a schematic flow chart of a method for manufacturing a schottky diode according to an embodiment of the present invention;
fig. 2 is a schematic cross-sectional structure diagram after an n-type gallium oxide layer is epitaxially grown on a substrate according to an embodiment of the present invention;
fig. 3 is a schematic cross-sectional structure diagram after a first mask layer is prepared on an n-type gallium oxide layer according to an embodiment of the present invention;
FIG. 4 is a schematic cross-sectional view of the front side of the device after high temperature annealing to form a thermal oxidation treatment region according to an embodiment of the present invention;
fig. 5 is a schematic cross-sectional structure diagram of the first mask layer removed according to the embodiment of the present invention;
FIG. 6 is a schematic cross-sectional view of a front side anode metal layer and a back side cathode metal layer prepared according to an embodiment of the present invention;
fig. 7 is a schematic cross-sectional structure diagram of a device formed when two first oxidation regions are provided according to an embodiment of the present invention;
fig. 8 to 11 are schematic cross-sectional views illustrating a schottky diode formed by a third thermal oxidation region according to an embodiment of the present invention;
fig. 12 is a schematic cross-sectional view of a schottky diode with two first thermal oxide regions and four third thermal oxide regions according to an embodiment of the present invention;
fig. 13 is a schematic cross-sectional structure diagram after a mask layer is deposited on an n-type gallium oxide layer according to an embodiment of the present invention;
FIG. 14 is a schematic cross-sectional view of a deposited insulating dielectric layer according to an embodiment of the present invention;
FIG. 15 is a schematic cross-sectional view illustrating a structure of an insulating medium layer removed from a predetermined anode region according to an embodiment of the present invention;
fig. 16 is a schematic cross-sectional view of the anode metal layer on the front side with a field plate structure and the cathode metal layer on the back side according to the embodiment of the present invention;
fig. 17 is a schematic cross-sectional view of a schottky diode having an anode metal layer on the front surface of a field plate structure according to an embodiment of the present invention, which corresponds to fig. 7;
fig. 18 is a schematic cross-sectional view of a schottky diode having an anode metal layer on the front surface of a field plate structure according to the embodiment of the present invention, which corresponds to fig. 11;
fig. 19 is a schematic cross-sectional view of a schottky diode having an anode metal layer on the front side of a field plate structure according to the embodiment of the present invention, which corresponds to fig. 12;
fig. 20 is a schematic cross-sectional structure diagram of a schottky diode according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings in combination with embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Fig. 1 is a schematic flow chart of a method for manufacturing a schottky diode according to an embodiment of the present invention, and referring to fig. 1, the method for manufacturing a schottky diode may include:
step S101, an n-type gallium oxide layer is extended on a substrate.
In the embodiment of the present invention, referring to fig. 2, the substrate 201 is an n-type heavily doped gallium oxide substrate. The n-type gallium oxide layer 202 is a lightly doped gallium oxide layer realized by doping Si or Sn, and the thickness of the n-type gallium oxide layer 202 is set according to actual requirements.
Step S102, preparing a first mask layer on the n-type gallium oxide layer; the window of the first mask layer is a region corresponding to a thermal oxidation treatment region to be prepared, and the thermal oxidation treatment region comprises at least one first thermal oxidation region and two second thermal oxidation regions.
In the embodiment of the present invention, referring to fig. 3, in order to form a thermal oxidation processing region in a specific region in a subsequent step, the first mask layer 204 may be first prepared in a region corresponding to a region other than the thermal oxidation processing region to be prepared, even though the window of the first mask layer 204 is the region corresponding to the thermal oxidation processing region to be prepared.
And step S103, carrying out high-temperature annealing treatment on the front surface of the device to form a thermal oxidation treatment area.
In the embodiment of the present invention, referring to fig. 4, the front surface of the device is subjected to a high temperature annealing process, and due to the shielding of the first mask layer 204, a thermal oxidation processing region is not formed in the n-type gallium oxide layer corresponding to the region where the first mask layer 204 exists, and a thermal oxidation processing region is formed in the n-type gallium oxide layer outside the region corresponding to the first mask layer.
And step S104, removing the first mask layer.
In an embodiment of the present invention, referring to fig. 5, the first mask layer is removed to form the device structure shown in fig. 5. The thermal oxidation treatment zones comprise a first thermal oxidation zone 2051 and a second thermal oxidation zone 2052, the classification of the oxidation treatment zones is carried out according to the relative positions of the oxidation treatment zones and the metal anode to be prepared, the first thermal oxidation zone 2051 is positioned in a zone corresponding to the position under the metal anode to be prepared, the number of the first thermal oxidation zone 2051 is at least one, and the second thermal oxidation zone 2052 is partially positioned in a zone corresponding to the position under the metal anode to be prepared, and the number of the second thermal oxidation zone 2052 is fixed to be two. Accordingly, when different numbers of the first thermal oxide regions 2051 are to be prepared, the window of the first mask layer is also changed accordingly.
Step S105, preparing an anode metal layer on the front side and a cathode metal layer on the back side; the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a first region, the region outside the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a second region, and the first thermal oxidation region is located in the first region; the first portion of each second thermal oxide region is located in the first region and the second portion of each second thermal oxide region is located in the second region.
In the embodiment of the present invention, referring to fig. 6, after the first mask layer is removed, the anode metal layer 206 is prepared on the front surface of the device, so that the left and right edges of the anode metal layer 206 are respectively located in the regions corresponding to the two second thermal oxide regions 2052, that is, the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a first region, the region other than the region corresponding to the projection of the anode metal layer on the n-type gallium oxide layer is a second region, when the anode metal layer is prepared, the first thermal oxide region 2051 is located in the first region, the first portion of each second thermal oxide region 2052 is located in the first region, and the second portion of each second thermal oxide region 2052 is located in the second region. Compared with an n-type gallium oxide layer which is not subjected to high-temperature annealing treatment, the thermal oxidation treatment region subjected to high-temperature annealing treatment has ion concentration difference, the thermal oxidation treatment region is formed at a specific position, and the relative positions of the anode metal layer 206 and the thermal oxidation treatment region are controlled, so that electric fields below the anode metal layer 206 and in the edge region can be reduced, reverse leakage of an anode is reduced, and breakdown and conduction characteristics are improved. When the number of the first oxidation regions is two, the device finally formed is as shown in fig. 7.
When the Schottky diode is prepared, the front surface of the device is subjected to high-temperature annealing treatment to form a thermal oxidation treatment area; and preparing a first mask layer on the n-type gallium oxide layer, and forming thermal oxidation treatment regions, namely forming at least one first thermal oxidation region and two second thermal oxidation regions, at specific positions in the n-type gallium oxide layer due to the shielding effect of the first mask layer. After the first mask layer is removed, preparing an anode metal layer on the front side of the device, and preparing a cathode metal layer on the back side of the device; and the left edge and the right edge of the anode metal layer are respectively positioned in the areas corresponding to the second thermal oxidation areas, and the first thermal oxidation area is positioned below the anode metal layer, so that electric fields below the anode metal and in the edge area are reduced, the reverse electric leakage of the anode is reduced, and the breakdown characteristic and the conduction characteristic are improved.
In some embodiments, referring to FIGS. 8-11, the thermal oxidation treatment zone further comprises: and the third thermal oxidation area is positioned in the second area.
In the embodiment of the invention, a plurality of thermal oxidation treatment regions can be formed on the drift layer through high-temperature annealing surface treatment, so that more concentration changes are introduced, and the breakdown characteristic of the device is further improved. Based on the device structure shown in fig. 2, a first mask layer 204 is prepared on the n-type gallium oxide layer 202, resulting in the device structure shown in fig. 8. Referring to fig. 9, the front surface of the device is subjected to high-temperature annealing treatment to form a thermal oxidation treatment region; after forming the thermal oxidation treatment region, removing the first mask layer 204 to form the device structure shown in fig. 10, where the thermal oxidation treatment region may further include, in addition to the first thermal oxidation region 2051 and the second thermal oxidation region 2052: a third thermal oxide 2053 located in said second zone. And then preparing an anode metal layer 206 on the front side and a cathode metal layer 207 on the back side on the device structure shown in fig. 10 to form the device structure shown in fig. 11. The structures provided in fig. 8-11 are merely illustrative, and there may be more of the first thermal oxidation zones and the third thermal oxidation zones, for example, the number of the first thermal oxidation zones may be two or more, and the number of the third thermal oxidation zones may be two or more; for example, in the structure provided in fig. 12, the number of the first thermal oxidation regions is two, and the number of the third thermal oxidation regions is four. In the embodiment of the invention, more transverse concentration changes are introduced into the n-type gallium oxide layer below the anode, so that the high-voltage resistance of the device is further improved.
In some embodiments, after forming the thermal oxidation treatment zone, the method further comprises: and performing high temperature annealing treatment on at least one of the first thermal oxidation region, the second thermal oxidation region and the third thermal oxidation region.
In an embodiment of the present invention, the high temperature annealing and re-processing is to form a plurality of first thermal oxide regions, second thermal oxide regions, and third thermal oxide regions with different concentrations and/or different depths, so as to improve the breakdown characteristic and the on characteristic of the device. After the front surface of the device is subjected to high-temperature annealing treatment to form a thermal oxidation treatment region, multiple times of high-temperature annealing retreatment can be further performed, wherein the treatment power and treatment time of the equipment can be changed when the high-temperature retreatment is performed each time, and the high-temperature annealing treatment with various powers and various times is performed. More thermal oxidation treatment regions with different concentrations and/or depths can be formed through multiple times of high-temperature retreatment, so that the breakdown characteristic and the conduction characteristic of the device are further improved.
In some embodiments, the substrate is an n-type gallium oxide substrate and the doping concentration is greater than the doping concentration of the n-type gallium oxide layer.
In the embodiment of the present invention, referring to fig. 2, the substrate 201 is an n-type gallium oxide substrate. The n-type gallium oxide layer 202 is epitaxially grown on the n-type gallium oxide substrate 201, wherein the doping concentration of the n-type gallium oxide layer 202 is less than that of the n-type gallium oxide substrate 201, which is more favorable for realizing high voltage resistance.
In some embodiments, the n-type gallium oxide layer is non-uniformly doped; the n-type gallium oxide layer is of a multilayer structure with the concentration increased from top to bottom.
In the embodiment of the invention, the n-type gallium oxide layer is of a multilayer structure with the concentration increased from top to bottom, so that high pressure resistance is realized.
In some embodiments, the preparing the first mask layer on the n-type gallium oxide layer may include: depositing a mask layer on the n-type gallium oxide layer; and removing the mask layer corresponding to the thermal oxidation treatment area to be prepared by photoetching and wet etching to form a first mask layer.
In the embodiment of the present invention, referring to fig. 13, a mask layer 203 may be deposited on an n-type gallium oxide layer 202, and then the mask layer 203 corresponding to a thermal oxidation processing region to be prepared may be removed by photolithography and wet etching, and a first mask layer may be formed in a corresponding region other than the thermal oxidation processing region to be prepared. In practice, the first mask layer is formed in a position and in a form that is prepared according to the position of the thermal oxidation treatment region to be prepared, and is finally formed to be composed of a plurality of discontinuous portions, such as the form of the first mask layer 204 in fig. 3 and 8.
In some embodiments, the first mask layer may include SiO2、Si3N4、Al2O3、HfO2And MgO.
In some embodiments, the removing the first mask layer may include: and putting the device forming the thermal oxidation treatment area into a preset solution until the first mask layer is removed, wherein the preset solution is an etching solution of the first mask layer.
In some embodiments, the preparing the anode metal layer of the front surface may include: after removing the first mask layer, depositing an insulating medium layer; removing the insulating medium layer of the preset anode region by dry etching or wet etching; preparing an anode metal layer with a front surface of a field plate structure; the field plate structure comprises a single-layer field plate structure, a multi-layer field plate structure and an inclined field plate structure; correspondingly, the preset anode region is a first region, and the region outside the preset anode region is a second region.
In the embodiment of the invention, after the first mask layer is removed, an insulating medium layer is deposited, and then the insulating medium layer in the preset anode region is removed through dry etching or wet etching; the preset anode region is a contact part of a positive anode metal layer with a field plate structure and the n-type gallium oxide layer, correspondingly, the preset anode region is a first region, and a region outside the preset anode region is a second region, so that transverse concentration change is introduced into the n-type gallium oxide layer below the anode, the electric field at the junction of the anode is optimized, the breakdown voltage is improved, and meanwhile, the on-resistance is considered. Meanwhile, compared with an anode metal layer without a field plate structure, the anode metal layer with the front surface of the field plate structure has better high-voltage resistance and conduction characteristics, and the structure of the field plate can be selected according to actual conditions, and comprises a single-layer field plate structure, a multi-layer field plate structure and an inclined field plate structure.
In some embodiments, an anode metal layer having a field plate structure can be formed on the device structure shown in fig. 5 and a back cathode metal layer can be prepared, which are shown in fig. 14-16.
In the embodiment of the invention, referring to fig. 14 to 16, after the first mask layer is removed, an insulating dielectric layer 208 is deposited, the insulating dielectric layer 208 in a preset anode region is removed by dry etching or wet etching, and an anode metal layer 206 with a front surface of a field plate structure is prepared; the preset anode region is a first region, and the region outside the preset anode region is a second region, so that transverse concentration change is introduced into the n-type gallium oxide layer below the anode, the electric field at the junction of the anode is optimized, the breakdown voltage is improved, and meanwhile, the on-resistance is considered. Preparing the anode metal layer 206 with the field plate structure and preparing the cathode metal layer 207 of the back side forms a schottky diode as described in fig. 16. In practice, the preparation of the cathode metal layer 207 may be performed in any of the above steps.
In some embodiments, as shown in the schottky diode structures shown in fig. 7, fig. 11 and fig. 12, the anode metal layer 206 may be an anode metal layer having a field plate structure, and the preparation steps thereof are the same as those described above and are not repeated herein, and the field plate structures corresponding to the anode metal layer are shown in fig. 17, fig. 18 and fig. 19.
Fig. 20 is a schematic cross-sectional view of a schottky diode according to an embodiment of the present invention, which includes:
a substrate 201;
an n-type gallium oxide layer 202 formed on the substrate 201;
an anode metal layer 206 formed on the n-type gallium oxide layer 202;
a cathode metal layer 207 formed on the back surface of the substrate 201;
wherein, the n-type gallium oxide layer 202 includes: at least one first thermal oxide region 2051 and two second thermal oxide regions 2052, a region corresponding to the projection of the anode metal layer 206 on the n-type gallium oxide layer 202 is a first region, a region of the anode metal layer 206 outside the region corresponding to the projection of the n-type gallium oxide layer 202 is a second region, and the first thermal oxide region 2051 is located in the first region and is in contact with the anode metal layer 206; a first portion of each second thermal oxide 2052 is located in a first region, a second portion of each second thermal oxide 2052 is located in a second region, and the first portion of each second thermal oxide 2052 is in contact with the anode metal layer 206.
According to the Schottky diode, the thermal oxidation treatment region is formed in the specific region of the upper surface of the n-type gallium oxide layer and comprises at least one first thermal oxidation region located in the region below the anode metal layer and two second thermal oxidation regions partially located below the anode metal layer, so that electric fields below the anode metal layer and in the edge region can be reduced, reverse leakage of an anode is reduced, and breakdown characteristics of a device are improved.
In some embodiments, the n-type gallium oxide layer further comprises: and the third thermal oxidation area is positioned in the second area, and the upper surface of the third thermal oxidation area is the upper surface of the n-type gallium oxide layer.
In some embodiments, the annealing temperature and the annealing time during the formation of the first thermal oxidation region, the second thermal oxidation region and the third thermal oxidation region are different.
In some embodiments, the substrate is an n-type gallium oxide substrate and the doping concentration is greater than the doping concentration of the n-type gallium oxide layer;
in some embodiments, the n-type gallium oxide layer is non-uniformly doped, and the n-type gallium oxide layer has a multilayer structure with increasing concentration from top to bottom.
The forming process of each portion in the schottky diode may refer to the corresponding process in the foregoing method embodiment, and details are not repeated here.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112820643A (en) * | 2020-12-28 | 2021-05-18 | 中国电子科技集团公司第十三研究所 | Preparation method and structure of gallium oxide SBD |
| CN113964183A (en) * | 2021-09-13 | 2022-01-21 | 西安电子科技大学 | Fluorine plasma injection terminal gallium oxide power diode and preparation method thereof |
| CN114709138A (en) * | 2022-02-11 | 2022-07-05 | 西安电子科技大学杭州研究院 | Gallium oxide Schottky diode and preparation method and preparation system thereof |
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| CN112820643B (en) * | 2020-12-28 | 2022-11-08 | 中国电子科技集团公司第十三研究所 | Preparation method and structure of gallium oxide SBD |
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| CN114709138A (en) * | 2022-02-11 | 2022-07-05 | 西安电子科技大学杭州研究院 | Gallium oxide Schottky diode and preparation method and preparation system thereof |
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