High-resistance GaN-based buffer layer with monolateral gradual change multi-quantum well and fabrication method of high-resistance GaN-based buffer layer

Abstract

The invention provides a high-resistance GaN-based buffer layer with a monolateral gradual change multi-quantum well. The high-resistance GaN-based buffer layer comprises a substrate, a nucleating layer, a GaN-based high-resistance buffer layer with the monolateral gradual change multi-quantum well and a GaN buffer layer which are sequentially laminated from bottom to top, wherein the GaN-based high-resistance buffer layer with the monolateral gradual change multi-quantum well comprises a plurality of multi-quantum well stress transfer layers, the contents of Al in the plurality of multi-quantum well stress transfer layers are sequentially reduced from bottom to top, the multi-quantum well stress transfer layer comprises a plurality of multi-quantum well periods, each multi-quantum well period further comprises an AlGa<1-u> gradual change transition layer with the gradual changed Al constituent and a high-Al constituent AlGa<1-a>N barrier layer and / or a low-Al constituent AlGa<1-b>N barrier layer, so that the content of the Al constituent in each layer in the multi-quantum period is monolaterally increased or reduced, and the number of the multi-quantum periods is 3-100.

Description

technical field [0001] The invention relates to an electronic component, in particular to a field effect transistor. Background technique [0002] How to obtain a high-quality and high-resistance buffer layer during the growth of GaN-based high electron mobility field-effect transistor (High Electron Mobility Transistor, HEMT) epitaxial material is one of the important key technologies for GaN-based HEMT epitaxy. When the HEMT device is working, the leakage of the GaN-based buffer layer will not only deteriorate the pinch-off performance of the device under high voltage conditions, but also weaken the control ability of the gate to the channel current, thereby deteriorating the overall performance of the device; at the same time, the leakage in the buffer layer will also It will increase the heat generation of the device, deteriorate the output characteristics of the device, reduce the power conversion efficiency, and affect the reliability and service life of the device. Th...

AI Technical Summary

Problems solved by technology

When the HEMT device is working, the leakage of the GaN-based buffer layer will not only deteriorate the pinch-off performance of the device under high voltage conditions, but also weaken the control ability of the gate to the channel current, thereby deteriorating the overall performance of the device; at the same time, the leakage in the buffer layer will also It will increase the heat generation of the device, deteriorate the output characteristics of the device, reduce the power conversion efficiency, and affect the reliability and service life of the device. Therefore, the leakage problem of the GaN-based buffer layer under high voltage has always been a problem that plagues the performance improvement of HEMT devices.

The first method is to obtain a high-resistance GaN epitaxial layer by introducing lattice defect impurities, so the crystal quality of the obtained high-resistance epitaxial layer will deteriorate

At the same time, the method of obtaining high-resistance GaN by controlling the growth conditions is highly dependent on equipment, and the repeatability is poor, and too many defect states will also aggravate the current collapse effect of the device, which seriously affects the reliability of the device; The introduction of metal impurities generally has a strong memory effect and will always remain in the reaction chamber, making the subsequent epitaxial materials have the risk of being contaminated by metal impurities. Therefore, it is generally necessary to have a dedicated doped MOCVD to grow high-resistance GaN-based epitaxial materials and remain. The metal impurities in the channel will reduce the mobility of the channel 2DEG and affect the device characteristics

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