Silicon carbide wafer thinning method

Abstract

The invention relates to a silicon carbide wafer thinning method. The method comprises the steps that aluminum is deposited on the back face of a silicon carbide wafer; thermal annealing is carried out on the silicon carbide wafer in a high-temperature reaction gas environment, so that silicon on the back surface of the silicon carbide wafer is mutually dissolved with aluminum, and carbon is separated out; and the aluminum, the mutually dissolved aluminum, the mutually dissolved silicon and the precipitated carbon on the back surface of the silicon carbide wafer are removed so as to realize thinning of the silicon carbide wafer. The method has the advantages that the physical and chemical properties of the surface layer of the back surface of the silicon carbide are changed by utilizing the mutual dissolution reaction of aluminum and silicon in the silicon carbide at high temperature, so that the hardness of the surface layer is reduced, and the aim of thinning the silicon carbide wafer by normally using a traditional silicon wafer thinning machine is fulfilled.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a silicon carbide (SiC) wafer thinning method. Background technique [0002] As a new generation of wide-bandgap semiconductor material, silicon carbide has extremely excellent performance in the field of power semiconductors, and is also the frontier and future direction of the development of power semiconductor devices. Silicon carbide is a compound semiconductor material composed of silicon (Si) and carbon (C), which has superior electrical properties, including a wide band gap of 2.3-3.3eV, which is three times that of silicon, and a high breakdown field strength of 0.8e16- 2e16V / cm is 10 times that of silicon, the high saturation drift velocity 2e7cm / s is 2.7 times that of silicon, and the high thermal conductivity 4.9W / cm K is 2.5 times that of silicon. These characteristics make silicon carbide materials have a large band gap and breakdown Excellent characteristics...

AI Technical Summary

Problems solved by technology

[0004] Based on this, it is necessary to provide a silicon carbide wafer thinning method for the problem that the silicon carbide wafer thinning process cannot be compatible with the current silicon wafer production line, which can be used without affecting the existing product preparation process and quality. Achieve the purpose of thinning silicon carbide wafers

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