Preparation method for GaN semiconductor device

Abstract

The invention provides a preparation method for a GaN semiconductor device. The preparation method comprises the following steps of depositing a hafnium oxide layer on the surface of a GaN epitaxial substrate; forming a source contact hole and a drain contact hole on the hafnium oxide layer; depositing a first metal layer in the source contact hole and the drain contact hole and on the surface of the hafnium oxide layer; forming an ohmic contact electrode window on the first metal layer; carrying out high temperature annealing processing on the whole device; carrying out etching to form a gate contact hole; depositing a second metal layer in the gate contact hole and the outer edge of the gate contact hole; depositing a silicon dioxide layer on the surface of the whole device; carrying out dry etching on the silicon dioxide layer on the source contact hole, thereby forming a hole; depositing field plate metal in the hole and the silicon dioxide layer stretching from the source contact hole to the gate contact hole, thereby forming a field plate metal layer. The electric leakage and breakdown problems of the GaN semiconductor device are avoided, the GaN semiconductor device is effectively protected, and the reliability of the GaN semiconductor device is improved.

Description

technical field [0001] The invention relates to the field of semiconductor technology, in particular to a method for preparing a gallium nitride semiconductor device. Background technique [0002] Because gallium nitride has the advantages of large band gap, high electron saturation rate, high breakdown electric field, high thermal conductivity, corrosion resistance and radiation resistance, gallium nitride can be used to make semiconductor materials, and gallium nitride semiconductors can be obtained device. [0003] In the prior art, the preparation method of the gallium nitride semiconductor device is: forming a silicon nitride layer on the surface of the gallium nitride epitaxial substrate, etching a source contact hole and a drain contact hole on the silicon nitride layer, the source Deposit metal in the electrode contact hole and drain contact hole to form the source and drain; then etch the silicon nitride layer and the aluminum gallium nitride layer in the gallium n...

AI Technical Summary

Problems solved by technology

[0005] The invention provides a method for preparing a gallium nitride semiconductor device, which is used to solve the problem of the current leakage and breakdown of the gallium nitride semiconductor device due to the relatively large edge electric field density of the field plate metal layer in the prior art, and further Problems that will damage gallium nitride semiconductor devices and reduce the reliability of gallium nitride semiconductor devices

Images