Normally-closed high-electron-mobility transistor and manufacturing method thereof

Abstract

The invention belongs to the technical field of semiconductors, and particularly relates to a normally-closed high-electron-mobility transistor and a manufacturing method thereof. According to the invention, a gate AlGaN layer and a P-type layer at a gate position and an AlGaN barrier layer in the area outside the gate can be independently designed and grown through a method of twice selective area epitaxy, and the components, the thickness and the like can be accurately controlled; therefore, optimal design of threshold voltage, two-dimensional electron gas concentration under the gate duringconduction and two-dimensional electron gas concentration of a conducting channel outside the gate during conduction is realized without mutual interference, meanwhile, dry etching is not involved inthe whole manufacturing process, wet selective corrosion is used instead, the surface quality of a transistor is protected to the maximum extent, and adverse consequence caused by dry etching are avoided. The normally-closed AlGaN / GaN high-electron-mobility transistor obtained on the basis of the manufacturing method disclosed by the invention has the advantages of high threshold voltage, threshold voltage consistency, low on resistance, high stability and the like.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, in particular to a normally-off high electron mobility transistor and a manufacturing method. Background technique [0002] Compared with the first and second-generation semiconductor materials, the third-generation semiconductor GaN material has the advantages of large band gap, high breakdown field strength, large electron mobility, and strong radiation resistance. GaN-based high electron mobility transistors are used in wireless High-frequency and high-power fields such as communication base stations, radars, and automotive electronics have great potential for development. The emergence of the AlGaN / GaN high electron mobility transistor (AlGaN / GaN HEMT) structure is based on the phenomenon described by T.Mimura et al. in 1975 and M.A.Khan et al. in 1994: the interface region between AlGaN and GaN heterostructures shows abnormal High electron mobility, often referred to as two-dimension...

AI Technical Summary

Problems solved by technology

At the same time, this solution does not solve the problems caused by dry etching the P-type layer in the area outside the gate.

[0006] It can be seen that in the prior art, in order to increase the threshold voltage of the normally closed AlGaN / GaN high electron mobility transistor, other problems will be caused, which is not conducive to the improvement of the comprehensive performance of the normally closed AlGaN / GaN high electron mobility transistor

That is to say, performances such as high threshold voltage, threshold voltage consistency, low on-resistance, and high stability cannot be achieved at the same time.

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