Normally-off gallium oxide-based MIS-HFET device

Abstract

The invention discloses a normally-off gallium oxide-based MIS-HFET device, and belongs to the technical field of semiconductor devices. The device comprises a substrate, a buffer layer and a channel layer which are sequentially stacked, and further comprises a first cap layer and a second cap layer which are arranged on the two sides of the upper end surface of the channel layer, wherein a barrier layer is arranged on the channel layer between the first cap layer and the second cap layer; a source electrode and a drain electrode are respectively arranged on the first cap layer and the second cap layer; a dielectric layer is arranged on the barrier layer, the source electrode and the drain electrode in a crossing mode, the edge of the dielectric layer extends downwards to wrap the barrier layer, the source electrode, the drain electrode, the first cap layer, the second cap layer and the channel layer, and the upper end of the source electrode and the upper end of the drain electrode penetrate out of the dielectric layer; and the dielectric layer is also connected with a gate electrode. According to the scheme, the device structure is formed in an etching barrier mode, normally-off operation of the device is simply and efficiently achieved, the process is controllable, the gate leakage current of the device is reduced by introducing the dielectric layer, and the gate breakdown voltage and the reliability of the device are improved.

Description

technical field [0001] The invention relates to the technical field of semiconductor devices, in particular to a normally-off gallium oxide-based MIS-HFET device. Background technique [0002] Power electronic devices are an important part of energy conversion, and efficient power conversion is accomplished through power devices. In compound semiconductor electronic power devices, the conductive channel of the heterojunction field effect transistor (HFET, also known as Modulation Doped Field Effect Transistor (MODFET) or High Electron Mobility Field Effect Transistor (HEMT)) passes through The two-dimensional electron gas (2DEG) with quantum effect in the heterojunction is formed, which separates electrons and donor impurities in space, avoids the scattering of impurities in the barrier layer, and greatly improves the mobility of electrons, so it is a very suitable for Devices for high frequency and high power applications. [0003] β-Ga 2 o 3 It has large band gap energ...

AI Technical Summary

Problems solved by technology

However, there is currently a lack of effective P-type doping and implantation techniques, and growing a thin barrier layer will lead to an increase in the parasitic resistance between the source and drain; in addition, although the etching recessed gate technology is a simple and efficient implementation Normally-off gallium oxide-based heterojunction field-effect transistor method, but the damage caused by the gate groove etching and the interface state will affect the performance of the device, causing problems such as increased gate leakage current and reduced channel electron mobility.

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