Wet etching method for electrode metal layer of silicon carbide device

Abstract

The invention provides a wet etching method for an electrode metal layer of a silicon carbide device. The method comprises the steps that the position of a silicon carbide wafer to be etched is adjusted, so that an electrode metal layer to be etched on the silicon carbide wafer is perpendicular to the liquid level of etching liquid, and a first preset angle is formed between the main positioning edge of the silicon carbide wafer and the liquid level of the etching liquid, and the first preset angle ranges from 40 degrees to 50 degrees; the silicon carbide wafer is immersed into the etching liquid according to a preset frequency so as to etch the electrode metal layer; wherein each time the silicon carbide wafer immersed in the etching liquid is taken out, the silicon carbide wafer is subjected to standing for a preset period of time. The etching difference of each tube core in the longitudinal direction and the transverse direction in the etching process of the electrode metal layer can be eliminated, hydrogen bubbles which are generated in the etching process of the electrode metal layer and are attached to the surface of the electrode metal layer can be eliminated, and etching residues are avoided. The electrical property and the yield of the device are improved, and the manufacturing cost is saved.

Description

technical field [0001] The present disclosure relates to the technical field of semiconductor devices, in particular to a wet etching method for an electrode metal layer of a silicon carbide device. Background technique [0002] Silicon carbide material has the advantages of wide bandgap, high thermal conductivity, high breakdown field strength, high saturation velocity, etc. The power device manufactured by it can greatly exert its high temperature, high frequency and low loss characteristics, making it in high voltage, High temperature, high frequency, high power, strong radiation and other aspects have great application prospects. [0003] In the manufacturing process of silicon carbide devices, the wet etching methods of the electrode metal layer on the silicon carbide wafer mainly include rotary spraying and tank immersion. In the tank body immersion etching method, due to many reasons such as vertical shaking of the robot arm and etching bubbles, the etching rate of t...

AI Technical Summary

Problems solved by technology

In the tank body immersion etching method, due to many reasons such as vertical shaking of the robot arm and etching bubbles, the etching rate of the same silicon carbide wafer is very different in the horizontal direction (X direction) and vertical direction (Y direction). (X direction) or vertical direction (Y direction) there is a large area of ​​etching residue, especially the etching uniformity at the edge of the die is very poor, which will eventually affect the electrical performance of silicon carbide devices and the yield of products

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