CN-122002837-A - Gallium nitride power device and preparation method thereof

CN122002837ACN 122002837 ACN122002837 ACN 122002837ACN-122002837-A

Abstract

The application discloses a gallium nitride power device and a preparation method of the gallium nitride power device, wherein the gallium nitride power device comprises a substrate, a buffer layer arranged on one side of the substrate, a channel layer arranged on one side of the buffer layer, which is away from the substrate, a barrier layer arranged on one side of the channel layer, which is away from the buffer layer, and the barrier layer and the channel layer can generate two-dimensional electron gas, a grid structure, a source electrode and a drain electrode which are arranged on one side of the barrier layer, which is away from the channel layer, at intervals, and the source electrode and the drain electrode are positioned on two sides of the grid structure, wherein the barrier layer between the grid structure and the drain electrode is provided with a first hollowed-out part, the thickness of the first hollowed-out part is the same as that of the barrier layer, and the first hollowed-out part is etched between the grid electrode and the drain electrode of the barrier layer, so that current leakage between the grid electrode and the drain electrode can be effectively inhibited, virtual grid effect is relieved, 2DEG electrons captured by an AlGaN barrier layer and a surface defect state trap and current collapse caused by the channel effect is improved, and the voltage withstanding performance and reliability of the device are improved.

Inventors

YUAN YAN
LIU CHENG
FU JIE
YE NIANCI
LIU HAO
ZHOU ZAN
ZHANG HUI

Assignees

湖南三安半导体有限责任公司

Dates

Publication Date: 20260508
Application Date: 20241031

Claims (10)

1. A gallium nitride power device, comprising: A substrate; the buffer layer is arranged on one side of the substrate; The channel layer is arranged on one side of the buffer layer, which is away from the substrate; The barrier layer is arranged on one side of the channel layer, which is far away from the buffer layer, and the barrier layer and the channel layer can generate two-dimensional electron gas; The barrier layer between the gate structure and the drain electrode is provided with a first hollowed-out part, the thickness of the first hollowed-out part is the same as that of the barrier layer, and the thickness direction is the direction from the substrate to the buffer layer.
2. The gallium nitride power device according to claim 1, wherein the channel layer between the gate structure and the drain electrode has a second hollowed-out portion, the second hollowed-out portion is disposed corresponding to the first hollowed-out portion, and a thickness of the second hollowed-out portion is less than or equal to a thickness of the channel layer.
3. The gallium nitride power device according to claim 2, wherein the first hollowed-out portion and/or the second hollowed-out portion has an inverted trapezoid structure.
4. The gallium nitride power device according to claim 2, wherein when the thickness of the second hollowed-out portion is smaller than the thickness of the channel layer, a carrier high-resistance layer is included between the buffer layer and the channel layer.
5. The gallium nitride power device of claim 4, wherein the carrier-high-resistance layer is an undoped gallium oxide semiconductor layer.
6. The gallium nitride power device according to claim 2, further comprising a carrier drift layer disposed between the buffer layer and the channel layer when the thickness of the second hollowed-out portion is equal to the thickness of the channel layer.
7. The gallium nitride power device of claim 5, wherein the carrier drift layer is a heavily doped gallium oxide semiconductor layer.
8. A method for manufacturing a gallium nitride power device, for manufacturing the power device according to claim 1, comprising: Providing a substrate; Forming a buffer layer on one side of the substrate; forming a channel layer on one side of the buffer layer away from the substrate; Forming a barrier layer which generates two-dimensional electron gas with the channel layer and is provided with a first hollowed-out part on one side of the communication layer, which is away from the buffer layer, wherein the thickness of the first hollowed-out part is the same as that of the barrier layer; and forming a gate electrode, a source electrode and a drain electrode respectively in the gate structure region, the source electrode region and the drain electrode region on one side of the barrier layer, which is away from the buffer layer.
9. The method according to claim 8, wherein, Before a barrier layer which generates two-dimensional electron gas with the channel layer and is provided with a first hollowed-out part is formed on one side of the communication layer, which is away from the buffer layer, The channel layer is provided with a second hollowed-out part, the thickness of the second hollowed-out part is smaller than or equal to that of the channel layer, and the second hollowed-out part is arranged corresponding to the first hollowed-out part.
10. The method according to claim 9, wherein, When the thickness of the second hollowed-out part is equal to the thickness of the channel layer, before the channel layer is formed on one side of the buffer layer away from the substrate, And forming a carrier drift layer on one side of the buffer layer, which is away from the substrate.

Description

Gallium nitride power device and preparation method thereof Technical Field The application relates to the technical field of semiconductors, in particular to a gallium nitride power device and a preparation method thereof. Background Gallium nitride (GaN) as a third generation wide band gap semiconductor material is superior in characteristics compared to conventional silicon (Si) -based semiconductor materials. The AlGaN/GaN heterojunction generates two-dimensional electron gas (2 DEG) with high electron concentration and high migration speed due to polarization effect, so that the device has excellent current processing capability and lower on-resistance, is beneficial to improving the overall energy efficiency of the device, and has wide application prospect in the aspect of power switching devices due to the characteristics. At present, although AlGaN/GaN devices have been greatly improved in terms of microwave and high-power device characteristics, there is still an important constraint, namely, a current collapse effect, and current leakage between gate drains is a problem that affects gate control capability, device voltage endurance capability and reliability. Disclosure of Invention The gallium nitride power device and the preparation method thereof provided by the application are used for effectively inhibiting current leakage between grid and drain, improving the current collapse effect and further improving the voltage resistance and the reliability of the device. In order to solve the technical problems, the first technical scheme provided by the application is that a gallium nitride power device is provided and comprises a substrate; the buffer layer is arranged on one side of the substrate; The channel layer is arranged on one side of the buffer layer, which is away from the substrate; The barrier layer is arranged on one side of the channel layer, which is far away from the buffer layer, and the barrier layer and the channel layer can generate two-dimensional electron gas; The barrier layer between the gate structure and the drain electrode is provided with a first hollowed-out part, the thickness of the first hollowed-out part is the same as that of the barrier layer, and the thickness direction is the direction from the substrate to the buffer layer. In an embodiment, the channel layer between the gate structure and the drain electrode has a second hollowed-out portion, the second hollowed-out portion is disposed corresponding to the first hollowed-out portion, and a thickness of the second hollowed-out portion is less than or equal to a thickness of the channel layer. In an embodiment, the first hollow portion and/or the second hollow portion have an inverted trapezoid structure. In an embodiment, when the thickness of the second hollowed-out portion is smaller than the thickness of the channel layer, a carrier high-resistance layer is included between the buffer layer and the channel layer. In one embodiment, the carrier high-resistance layer is an undoped gallium oxide semiconductor layer. In an embodiment, when the thickness of the second hollowed-out portion is equal to the thickness of the channel layer, the second hollowed-out portion further includes a carrier drift layer disposed between the buffer layer and the channel layer. In one embodiment, the carrier drift layer is a heavily doped gallium oxide semiconductor layer. In order to solve the technical problems, the second technical scheme provided by the application is that a preparation method of a gallium nitride power device is provided, comprising the steps of providing a substrate; Forming a buffer layer on one side of the substrate; forming a channel layer on one side of the buffer layer away from the substrate; Forming a barrier layer which generates two-dimensional electron gas with the channel layer and is provided with a first hollowed-out part on one side of the communication layer, which is away from the buffer layer, wherein the thickness of the first hollowed-out part is the same as that of the barrier layer; and forming a gate electrode, a source electrode and a drain electrode respectively in the gate structure region, the source electrode region and the drain electrode region on one side of the barrier layer, which is away from the buffer layer. In an embodiment, before the barrier layer which generates the two-dimensional electron gas with the channel layer and has the first hollowed-out portion is formed on one side of the communication layer away from the buffer layer, a second hollowed-out portion is formed on the channel layer, the thickness of the second hollowed-out portion is smaller than or equal to that of the channel layer, and the second hollowed-out portion and the first hollowed-out portion are correspondingly arranged. In one embodiment, when the thickness of the second hollowed-out portion is equal to the thickness of the channel layer, before the channel layer is formed on the side of the buffe