CN-121985554-A - Schottky and ohmic mixed drain enhancement type GaN high electron mobility transistor

CN121985554ACN 121985554 ACN121985554 ACN 121985554ACN-121985554-A

Abstract

The invention relates to the technical field of semiconductors, in particular to a Schottky and ohmic mixed drain electrode enhanced GaN high electron mobility transistor, which comprises a metal source electrode, a metal grid electrode, a P-GaN region, a first Schottky drain electrode, an ohmic drain electrode, a second Schottky drain electrode, an AlGaN barrier layer, a GaN channel layer, an AlGaN buffer layer, an AlN nucleation layer and a substrate layer, wherein the first Schottky drain electrode contacts with metal to have the effect similar to a field plate, and the channel modulation and the electric field modulation of the second Schottky drain electrode contact etched to the GaN channel layer can effectively optimize the electric field distribution of a drain end and improve the withstand voltage of a device, and meanwhile, under the effect of improving the electric field distribution by the first Schottky drain electrode and the second Schottky drain electrode contact, the current can be led to flow to the whole ohmic region more effectively, so that the electron injection is more sufficient, the effective channel width is increased, the current crowding can be obviously improved, the on resistance is reduced, the output current is improved, and the contradiction between the on resistance and the withstand voltage of the device is solved.

Inventors

LIU XINGPENG
PAN PENGYU
LI QI
LI HAIOU
DENG WEIPING

Assignees

桂林电子科技大学

Dates

Publication Date: 20260505
Application Date: 20260116

Claims (5)

1. A schottky and ohmic hybrid drain enhanced GaN high electron mobility transistor characterized by, The GaN-based semiconductor device comprises a metal source electrode, a metal gate electrode, a P-GaN region, a first Schottky drain electrode, an ohmic drain electrode, a second Schottky drain electrode, an AlGaN barrier layer, a GaN channel layer, an AlGaN buffer layer, an AlN nucleation layer and a substrate layer; The metal source is assembled at the top of the GaN channel layer, the second Schottky drain is assembled at the top of the GaN channel layer, the AlGaN barrier layer is fixedly connected with the GaN channel layer and is positioned between the metal source and the second Schottky drain, the P-GaN region is fixedly connected with the AlGaN barrier layer and is positioned near one side of the metal source, the metal gate is fixedly connected with the P-GaN region and is positioned on one side of the P-GaN region, which is far away from the AlGaN barrier layer, the first Schottky drain is fixedly connected with the AlGaN barrier layer and is positioned near one side of the second Schottky drain, the ohmic drain is fixedly connected with the AlGaN barrier layer and is positioned between the first Schottky drain and the second Schottky drain, the AlGaN buffer layer is fixedly connected with the GaN channel layer and is positioned at the bottom of the GaN channel layer, the nucleation layer is fixedly connected with the AlGaN buffer layer and is positioned on one side, which is far away from the AlGaN channel layer and is fixedly connected with the substrate layer.
2. The schottky and ohmic hybrid drain-enhanced GaN high electron mobility transistor of claim 1, The P-GaN region 3 is doped with P-type impurity with the concentration of 。
3. The schottky and ohmic hybrid drain-enhanced GaN high electron mobility transistor of claim 1, The metal source electrode and the ohmic drain electrode are made of Ti/Al/Ni/Au, the metal gate electrode, the first Schottky drain electrode and the second Schottky drain electrode are made of Ni/Au or Pt/Au, and the substrate layer is made of sapphire or Si.
4. The schottky and ohmic hybrid drain-enhanced GaN high electron mobility transistor of claim 1, The metal source, the metal gate, the P-GaN region, the first schottky drain, the ohmic drain, and the second schottky drain are covered with a passivation layer.
5. The schottky and ohmic hybrid drain-enhanced GaN high electron mobility transistor of claim 1, The width and thickness of the metal source electrode are respectively equal to those of the second Schottky drain electrode, and the width of the metal source electrode 0.5Um, thickness 0.245Um, the second Schottky drain electrode 6 width 0.5Um, thickness Width of the first Schottky drain is 0.245um 0.5Um, width of the ohmic drain electrode 1.0Um thickness Is 0.2um.

Description

Schottky and ohmic mixed drain enhancement type GaN high electron mobility transistor Technical Field The invention relates to the technical field of semiconductors, in particular to a Schottky and ohmic mixed drain electrode enhanced GaN high electron mobility transistor. Background With the rapid development of the information age, a large number of application occasions are not separated from a large-power semiconductor device, the large-power semiconductor device naturally becomes an international research hot spot, and with the technical development of the whole industry chain, the various technologies including epitaxy, manufacturing, packaging, systems and the like are improved, and the power semiconductor device is comprehensively expanded in power density, energy conversion efficiency and application scenes. Silicon has been the most widely used semiconductor material for many advantages as the first generation semiconductor material and its process is currently the most mature in several decades of this rapid development. However, in order to solve the contradiction between the on-resistance and the withstand voltage of the device in the high-voltage application scene, the traditional silicon-based device has gradually approached the limit of the Si material through multiple technical iterations, and the cost is higher and higher, so that new materials are needed to break through the performance limit of the device. As such, gallium nitride, which is a third generation semiconductor material, has significant advantages in terms of a larger forbidden bandwidth, a higher breakdown electric field, a higher electron mobility, and excellent heat conduction properties, is considered as a core component in future electronic systems. Although GaN high electron mobility transistors have been widely used in recent years, most commercial GaN high electron mobility transistors have drains with ohmic contacts as the main source, the ohmic contacts have low on-resistance, stable threshold voltage but low withstand voltage, and complex process, and the whole device is electrically conductive by using two-dimensional electron gas as a single effective carrier, which has the problem of low current density, the drain electrode of a part of commercial GaN high electron mobility transistors is mainly in Schottky contact, and the Schottky contact drain electrode improves the voltage resistance, has simple process, but greatly improves the on-resistance and increases the switching loss, so that the problem of contradiction between the on-resistance and the voltage resistance of the device and the problem of how to realize current expansion are the problems to be solved in the current GaN high electron mobility transistors. Disclosure of Invention The invention aims to provide a Schottky and ohmic mixed drain electrode enhanced GaN high electron mobility transistor, which solves the problem of contradiction between on-resistance and withstand voltage of a device. In order to achieve the above object, the present invention provides a schottky and ohmic hybrid drain enhanced GaN high electron mobility transistor comprising a metal source, a metal gate, a P-GaN region, a first schottky drain, an ohmic drain, a second schottky drain, an AlGaN barrier layer, a GaN channel layer, an AlGaN buffer layer, an AlN nucleation layer, and a substrate layer; The metal source is assembled at the top of the GaN channel layer, the second Schottky drain is assembled at the top of the GaN channel layer, the AlGaN barrier layer is fixedly connected with the GaN channel layer and is positioned between the metal source and the second Schottky drain, the P-GaN region is fixedly connected with the AlGaN barrier layer and is positioned near one side of the metal source, the metal gate is fixedly connected with the P-GaN region and is positioned on one side of the P-GaN region, which is far away from the AlGaN barrier layer, the first Schottky drain is fixedly connected with the AlGaN barrier layer and is positioned near one side of the second Schottky drain, the ohmic drain is fixedly connected with the AlGaN barrier layer and is positioned between the first Schottky drain and the second Schottky drain, the AlGaN buffer layer is fixedly connected with the GaN channel layer and is positioned at the bottom of the GaN channel layer, the nucleation layer is fixedly connected with the AlGaN buffer layer and is positioned on one side, which is far away from the AlGaN channel layer and is fixedly connected with the substrate layer. Wherein the P-GaN region 3 is doped with P-type impurities with the concentration of。 The metal source electrode and the ohmic drain electrode are made of Ti/Al/Ni/Au, the metal gate electrode, the first Schottky drain electrode and the second Schottky drain electrode are made of Ni/Au or Pt/Au, and the substrate layer is made of sapphire or Si. Wherein the metal source, the metal gate, the P-GaN region, the first schottky d