SiC substrate double-pulse femtosecond laser slicing method

Abstract

The invention discloses a SiC substrate double-pulse femtosecond laser slicing and stripping method, which comprises the following steps of: after low-energy femtosecond laser double-pulse cutting, generating enough internal stress by adopting a'fast heating and cooling-stripping 'method, further destroying an amorphous structure after laser cutting, and reducing the size of required mechanical stress for external stripping. Through a double-pulse laser slicing means, the thickness of a damaged layer caused in the laser slicing process is greatly reduced, and a large amount of waste of materials is avoided; meanwhile, by means of'fast heating and cooling ', the external tension required by stripping after slicing is greatly reduced, so that the slices can be easily stripped; the method is low in material loss, short in processing time, low in cost and low in environmental pollution.

Description

technical field [0001] The invention belongs to the technical field of semiconductors and relates to cutting of silicon carbide, in particular to a method for slicing a SiC substrate with a double-pulse femtosecond laser. Background technique [0002] With the development of science and technology, people have higher and higher requirements for electronic devices, and high temperature, high frequency, radiation resistance and high power have become the most basic requirements. The third-generation semiconductor materials have characteristics such as wider bandgap, higher thermal conductivity, higher radiation resistance, and greater electron saturation drift rate, and have important application values ​​in the fields of optoelectronics and microelectronics. SiC is a typical representative of the third-generation semiconductor, but its hardness is very high, with a Mohs hardness of 9.5, second only to diamond (10), and it is not easy to cut. The existing SiC cutting methods ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problems of large material loss, long processing time, high cost and serious environmental pollution in the traditional slicing method; Due to defects such as excessive height and excessive slice damage thickness, a method for stripping SiC substrate double-pulse femtosecond laser slices combined with a "heating-cooling" process is proposed. After cutting with low-energy femtosecond laser double pulses, "fast heating "Cold-stripping" method to generate sufficient internal stress, further destroy the amorphous structure after laser cutting, and reduce the required external peeling mechanical stress

Images