A method for improving warpage of 6-inch sic wafer

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a method for improving the warpage of a 6-inch SiC wafer. The method comprises the following steps: S1, carrying out spin coating of paraffin wax on the front side of the SiC wafer and the front side of a SiC slide and baking the paraffin wax; S2, taking the surface, subjected to spin coating of the paraffin wax, of the SiC wafer and the surface, subjected to spin coating of the paraffin wax, of the SiC slide as intermediate layers, and bonding the SiC wafer and the SiC slide together. According to the method disclosed by the invention, a SiC material made of a material identical with that of a to-be-treated wafer are used as the slide, the paraffin wax is used as a binding agent, the front side of the SiC wafer and the front side of the SiC slide are subjected to spin coating of the paraffin wax, and finally, the SiC wafer and the SiC slide are bonded together, thereby reducing the warpage of a 6-inch SiC wafer and avoiding the phenomenon that the bonding is damaged due to nitric acid dissolution; the warpage can be effectively controlled within 50mu m, and a subsequent manufacturing process is facilitated.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a method for improving the warpage of a 6-inch SiC wafer. Background technique [0002] As the third-generation wide bandgap compound semiconductor device, AlGaN / GaN HEMT has excellent characteristics in terms of power output and frequency characteristics, making it have a good application prospect in high temperature, high frequency, and high power devices. has been extensively researched. [0003] SiC is selected as the preferred substrate material for AlGaN / GaN HEMTs to manufacture SiC-based AlGaN / GaN HEMT devices. SiC-based AlGaN / GaN HEMT devices need to be thinned and etched through holes for grounding, so as to improve the frequency characteristics and reliability of the device, and facilitate the design and manufacture of microwave monolithic integrated circuits. Currently, the through-holes of SiC-based AlGaN / GaN HEMT devices are necessary...

AI Technical Summary

Problems solved by technology

However, for the 6-inch SiC material, limited by its growth technology, the substrate itself of the SiC material warps by about 10 μm, coupled with the stress and stretch caused by the GaN epitaxial layer, the warpage increases to about 50 μm, This is already the best level in the country

After the general bonding process, the warpage will increase to more than 70μm, and such a large warpage will have a great impact on the backside process of the wafer

However, there is currently no method that can effectively reduce the warpage of 6-inch SiC-based GaN power semiconductor devices

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