Si-based AlGaN/GaN HEMT based on wrapping buried layer and diffusion barrier layer and preparation method

Abstract

The invention relates to a Si-based AlGaN / GaN HEMT based on a wrapping buried layer and a diffusion barrier layer and a preparation method. The Si-based AlGaN / GaN HEMT comprises a Si substrate, the diffusion barrier layer, an AlN nucleating layer, an AlGaN order change layer, a GaN buffer layer and an AlGaN barrier layer which are stacked in sequence, an N-type buried layer and an isolation layer are arranged in the Si substrate, and the isolation layer is arranged between the Si substrate and the N-type buried layer and wraps the N-type buried layer. According to the AlGaN / GaN HEMT, an N-type buried layer and an isolation layer are arranged in a Si substrate, the isolation layer cannot completely mask N-type impurities in the N-type buried layer, and the N-type impurities can be diffused into the Si substrate so that the concentration of a P-type channel introduced into the Si substrate by diffusion of Al in an upper layer structure is counteracted, the resistivity of the substrate is improved, and the radio frequency loss of a device is reduced; and meanwhile, the diffusion barrier layer is arranged between the Si substrate and the AlN nucleating layer, and the diffusion barrier layer can achieve the effect of blocking diffusion of Al atoms so that P-type conductive doping in the substrate is reduced, the resistivity of the substrate is improved, and then the radio frequency loss of the substrate is reduced.

Description

technical field [0001] The invention belongs to the technical field of semiconductor materials, and in particular relates to a Si-based AlGaN / GaN HEMT based on a wrapping buried layer and a diffusion barrier layer and a preparation method. Background technique [0002] As a typical representative of the third-generation wide-bandgap semiconductor materials, GaN is widely used in radio frequency devices, light-emitting diodes and in power electronics. AlGaN / GaN high electron mobility transistor (High Electron Mobility Transistor, HEMT), as a commonly used GaN structure, is widely used in emerging 5G communications, radar and Space exploration and other fields, but it also puts forward high requirements on the radio frequency performance of AlGaN / GaN HEMT devices. [0003] Conventional AlGaN / GaN HENT heteroepitaxy substrates are made of SiC, sapphire and Si substrates. Although SiC has the best performance, its large-scale commercial application is limited due to the high c...

AI Technical Summary

Problems solved by technology

However, the radio frequency loss of silicon-based AlGaN / GaN HEMT is relatively large. One source of radio frequency loss is caused by the P-type conductive channel formed by Al diffusion into the silicon substrate. This conductive channel will increase additional radio frequency loss and make the substrate The resistivity of the bottom is reduced, and the RF loss is increased

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