Preparation method of enhanced GaN HEMT

Abstract

The invention discloses a preparation method of an enhanced GaN HEMT, comprising the following steps: epitaxially forming a buffer layer, a channel layer, a barrier layer and a p type cap layer in sequence on a substrate through a metal-organic chemical vapor deposition method; preparing a mask layer on the p type cap layer; patterning the mask layer, exposing the p type cap layer of a grid regionpart and then forming a sample; epitaxially forming a p type layer on the exposed p type cap layer of the sample to form a p type grid, namely, epitaxially forming the p type grid in a selected region for the second time; removing the mask layer; etching down to the inside of the channel layer at two sides of the p type cap layer, constructing a table at the two sides of the channel layer and forming table isolation; preparing a source electrode and a drain electrode on the p type cap layer at two sides of the p type grid, and annealing; preparing a grid electrode on the p type grid and forming a device; preparing a passivation layer on the device, wherein the thickness of the passivation layer is higher than the p type grid, and opening the passivation layer of a region of the source electrode, the drain electrode and the grid electrode, namely, exposing the source electrode, the drain electrode and the grid electrode, thereby completing preparation.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, in particular to a method for preparing an enhanced high electron mobility transistor and a semiconductor device including the transistor. Background technique [0002] GaN-based power electronic devices have attracted a lot of attention in recent years. GaN materials can form heterojunction structures with AlGaN, InGaN and other materials. Due to the spontaneous polarization and piezoelectric polarization effects of the barrier layer materials, a high concentration of two-dimensional electron gas (2DEG) will be formed at the heterojunction interface. Due to the advantages of GaN materials such as large band gap, high electron mobility, high electron saturation velocity, and large breakdown field strength, GaN HEMTs have become a research hotspot in the field of microwave power and circuits in the past decade. [0003] Although GaN HEMT has many advantages, it also encounters many proble...

AI Technical Summary

Problems solved by technology

During the etching and etching process of these two methods, the plasma will damage the interface and affect the stability of the device; the third method for the p-type gate is to perform selective secondary epitaxy on the gate region on the barrier layer to grow the p-type gate. This method avoids the lattice damage caused by etching, but due to the lattice mismatch and interface state between the barrier layer and the p-type gate, it causes serious leakage problems

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