阅读说明：本技术 一种增强型GaN基高电子迁移率晶体管材料结构 (Enhanced GaN-based high electron mobility transistor material structure ) 是由 王晓亮 李百泉 肖红领 冯春 姜丽娟 殷海波 李天运 邱爱芹 介芳 于 2019-10-28 设计创作，主要内容包括：本发明公开了一种增强型GaN基高电子迁移率晶体管材料结构,所述晶体管材料结构从下至上依次包括：衬底、成核层、缓冲层、氮化镓沟道层、氮化铝插入层、铝镓氮势垒层和铟镓氮盖帽层。本发明在AlGaN/GaN异质结上增加一InGaN帽层,利用InGaN相对于AlGaN反的极化作用,从而在InGaN/AlGaN界面处形成负的极化电荷,而抬高AlGaN/GaN界面处的导带底位置,实现增强型器件用外延材料。(The invention discloses an enhanced GaN-based high electron mobility transistor material structure, which sequentially comprises the following components from bottom to top: the device comprises a substrate, a nucleation layer, a buffer layer, a gallium nitride channel layer, an aluminum nitride insertion layer, an aluminum gallium nitride barrier layer and an indium gallium nitride cap layer. According to the invention, an InGaN cap layer is added on the AlGaN/GaN heterojunction, and negative polarization charges are formed at an InGaN/AlGaN interface by utilizing the polarization action of InGaN opposite to AlGaN, so that the position of the bottom of a conduction band at the AlGaN/GaN interface is raised, and the epitaxial material for the enhanced device is realized.)

1. The utility model provides an enhancement mode GaN base HEMT material structure which follows supreme and includes in proper order: the device comprises a substrate, a nucleation layer, a buffer layer, a gallium nitride channel layer, an aluminum nitride insertion layer, an aluminum gallium nitride barrier layer and an indium gallium nitride cap layer.

2. The enhanced GaN-based high electron mobility transistor material structure of claim 1, wherein the thickness of the gallium nitride channel layer is 50-200 nm; the thickness of the aluminum nitride insertion layer is 0.5-5 nm.

3. The enhanced GaN-based HEMT material structure of claim 1, wherein the AlGaN barrier layer is made of Al_xGa_1-xN, wherein x is more than or equal to 0.1 and less than or equal to 1, and the thickness of the material is 5-50 nm.

4. The enhanced GaN-based HEMT material structure of claim 1, wherein the buffer layer is made of Al_yGa_1-yN, wherein 0 is less than or equal to y<0.10 and a thickness of 0.5 to 5 mu m.

5. The enhanced GaN-based high electron mobility transistor material structure of claim 1, wherein the material of the nucleation layer is GaN or AlN with a thickness of 0.01-0.50 μm.

6. The enhanced GaN-based hemt material structure of claim 1, wherein said substrate is made of any one of sapphire, silicon carbide, gallium nitride and aluminum nitride.

7. The enhanced GaN based hemt of claim 1, wherein said ingan cap layer has a thickness of 1-50 nm.

Technical Field

The invention belongs to the technical field of semiconductors, and particularly relates to a material structure of an enhanced GaN-based high electron mobility transistor.

Background

Gallium nitride as a typical representative of third-generation semiconductor materials has the characteristics of large forbidden band width, high electron saturation drift velocity, high breakdown voltage, stable chemical properties, high radiation resistance and the like, is particularly suitable for preparing transistors with high temperature, high frequency, high power and radiation resistance, and has wide application prospects in the fields of radar, satellite communication, aerospace, oil exploration, automotive electronics, automatic control and the like.

The working principle of the gallium nitride-based heterojunction field effect transistor is as follows: because the forbidden band widths of two materials forming the heterojunction are different, a potential well and a potential barrier are formed at the interface of the heterojunction, and free electrons generated by polarization effect or modulation doping are accumulated in a triangular potential well of the undoped gallium nitride layer close to the interface to form two-dimensional electron gas. The heterostructure material is developed into a field effect transistor device, and the cut-off and saturation of the device can be regulated and controlled through the grid voltage, so that the switching function is realized. However, in general, such a device is a depletion mode device, when a negative gate voltage is increased, a depletion layer is deepened, the electron density of a channel is gradually reduced until the channel is completely depleted, and the device realizes an off-state function. Compared with a depletion mode device, the enhancement mode device can simplify a grid driving circuit and realize a safer switching circuit.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide an enhanced GaN-based high electron mobility transistor material structure, which utilizes an indium gallium nitride cap layer to exhaust two-dimensional electron gas in a GaN-based high electron mobility transistor channel, thereby realizing the development of the enhanced GaN-based high electron mobility transistor material structure.

In order to achieve the purpose, the invention adopts the following technical scheme:

an enhanced GaN-based HEMT material structure, comprising from bottom to top in order: the device comprises a substrate, a nucleation layer, a buffer layer, a gallium nitride channel layer, an aluminum nitride insertion layer, an aluminum gallium nitride barrier layer and an indium gallium nitride cap layer.

Further, the thickness of the gallium nitride channel layer is 50-200 nm; the thickness of the aluminum nitride insertion layer is 0.5-5 nm.

Further, the AlGaN barrier layer is made of Al_xGa_1-xN, wherein x is more than or equal to 0.1 and less than or equal to 1, and the thickness of the material is 5-50 nm.

Further, the buffer layer is made of Al_yGa_1-yN, wherein 0 is less than or equal to y<0.10 and a thickness of 0.5 to 5 mu m.

Further, the material of the nucleation layer is GaN or AlN, and the thickness is 0.01-0.50 mu m.

Further, the substrate is made of any one of sapphire, silicon carbide, gallium nitride, and aluminum nitride.

Further, the thickness of the indium gallium nitride cap layer is 1-50 nm.

The invention has the following beneficial technical effects:

according to the invention, an InGaN cap layer is added on the AlGaN/GaN heterojunction, and negative polarization charges are formed at an InGaN/AlGaN interface by utilizing the polarization action of InGaN opposite to AlGaN, so that the position of the bottom of a conduction band at the AlGaN/GaN interface is raised, and the epitaxial material for the enhanced device is realized.

Drawings

FIG. 1 is a structural diagram of the material structure of the enhanced GaN-based HEMT of the present invention.

Detailed Description

The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

As shown in fig. 1, the present invention provides an enhanced GaN-based hemt material structure, which sequentially comprises, from bottom to top: the device comprises a substrate, a nucleation layer, a buffer layer, a gallium nitride channel layer, an aluminum nitride insertion layer, an aluminum gallium nitride barrier layer and an indium gallium nitride cap layer.

The thickness of the gallium nitride channel layer is 50-200 nm; the thickness of the aluminum nitride insertion layer is 0.5-5 nm.

The Al-Ga-N barrier layer is made of Al_xGa_1-xN, wherein x is more than or equal to 0.1 and less than or equal to 1, and the thickness of the material is 5-50 nm.

The buffer layer is made of Al_yGa_1-yN, wherein 0 is less than or equal to y<0.10 and a thickness of 0.5 to 5 mu m.

The material of the nucleation layer is GaN or AlN, and the thickness is 0.01-0.50 mu m.

The substrate is made of any one of sapphire, silicon carbide, gallium nitride, and aluminum nitride.

The thickness of the indium gallium nitride cap layer is 1-50 nm; the invention utilizes the indium gallium nitride cap layer to exhaust two-dimensional electron gas in the GaN-based high electron mobility transistor channel, thereby realizing the structural development of the enhanced GaN-based high electron mobility transistor.

The above description is only for the purpose of illustrating the present invention, and it should be understood that the present invention is not limited to the above embodiments, and various modifications conforming to the spirit of the present invention are within the scope of the present invention.