Method for cutting wafer of high-power power electronic device by invisible laser

Abstract

The invention discloses a method for cutting a high-power power electronic device by an invisible laser. The high-power power electronic device comprises an epitaxial layer with a substrate of semiconductor materials and is formed in the surface of the substrate. The method for cutting a chip of the high-power power electronic device comprises the steps that an invisible laser scribing is conducted on the back side of the substrate of the high-power power electronic device, and then a front splinter is conducted by a splinter machine according to scratches in the inner portion. The depth of the scratches in the inner portion is about one tenths to a half of the thickness of the chip. The method for cutting a wafer of the high-power power electronic device by the invisible laser uses a method of cutting the to-be-cut inner portion of the chip by laser beam focusing, the laser beam is adopted to cut the inner portion of the high-power power electronic device, and a laser energy region is located on the lower half portion of the chip and namely is close to a substrate region. The laser invisible cutting is adopted, so that an active region of the front side of the chip is furthest guaranteed, the front side of a region is not broken, the device with a neat edge is obtained, and the productivity and the reliability of the chip with a large region are highly improved.

Description

【Technical field】 [0001] The invention relates to a semiconductor power device preparation process, in particular to a process for dividing a high-power device wafer into single chips during the preparation process of a high-power power electronic device. 【Background technique】 [0002] The use environment and conditions of power electronic devices are getting worse and worse, and they must adapt to special environments such as high frequency, high power, high temperature resistance, and radiation resistance. In order to meet the needs of future electronic devices, new materials must be used in order to maximize the intrinsic performance of electronic components. In recent years, the newly developed third-generation semiconductor materials - wide bandgap semiconductor materials, such as silicon carbide and gallium nitride, have the characteristics of high thermal conductivity, high electron saturation velocity, high breakdown voltage, and low dielectric constant. This theor...

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the unavoidable chip surface damage in the existing laser cutting, the generation of breakdown points destroys the reliability of the chip, etc., the present invention provides a stealth laser cutting technology, which uses a short-wavelength laser beam to focus on the inside of the wafer , causing a local burst inside, forming an internal modified layer, and forming cracks facing the two sides of the outside at the same time, and applying force to the crack will cause the crack of the sample

Images