Epitaxial growth method for reducing interface thermal resistance of gallium nitride high-electron-mobility field-effect transistor

Abstract

The invention relates to an epitaxial growth method for reducing interface thermal resistance of a gallium nitride high-electron-mobility field-effect transistor. An epitaxial material is grown through a vapor phase epitaxial growth method of metal organic matter chemical vapor deposition and the like. A gallium nitride epitaxial wafer comprises a substrate, a lower aluminium nitride nucleating layer, an upper aluminium nitride nucleating layer, a gallium nitride transition layer, a gallium nitride buffer layer, a barrier layer and a cap layer from the bottom up in sequence. The carrier gasesused in the growing process of the lower aluminium nitride nucleating layer and the upper aluminium nitride nucleating layer are hydrogen and nitrogen respectively. The carrier gas used in the growingprocess of the gallium nitride transition layer is nitrogen. The carrier gas used in the growing process of the gallium nitride buffer layer is hydrogen or a mixture of hydrogen and nitrogen. Throughthe carrier gas conversion process, the method reduces defect density in the aluminum nitride nucleating layer and the gallium nitride layer, improves interface quality of the aluminum nitride nucleating layer and the gallium nitride layer, and effectively reduces the interface thermal resistance of the gallium nitride high-electron-mobility field-effect transistor.

Description

technical field [0001] The invention belongs to the technical field of semiconductor epitaxial materials, and in particular relates to an epitaxial growth method for reducing the interface thermal resistance of a GaN high electron mobility field effect tube. Background technique [0002] Gallium nitride high electron mobility field effect transistor has the advantages of high output power density, high operating frequency, and radiation resistance. It has unique advantages in the application of microwave power devices, and is developing rapidly in the direction of millimeter wave and high power. Among them, the cut-off frequency has reached 450GHz, and the output power of Ka-band has reached more than 40W. However, in the radio frequency state, a large amount of heat energy is generated near the device channel, which imposes strict requirements on the thermal management capability of the device. However, the performance of current microwave power devices is limited by the i...

AI Technical Summary

Problems solved by technology

However, under the conventional aluminum nitride nucleation layer process, the lateral migration length of aluminum atoms is low, which is not conducive to the lateral merger between nucleation layer islands, which leads to many mismatch defects in the nucleation layer, poor surface morphology, and nitrogen The high density of mismatch defects in the Al2 nucleation layer extends to the GaN layer resulting in a higher threading dislocation density in the GaN layer

In addition, gallium nitride is a large mismatch heteroepitaxy, and thinning the thickness of the gallium nitride layer will also deteriorate the quality of its own materials

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