We report on a fast machining process for cutting silicon wafers using laser radiation without melting or ablating and
without additional pretreatment.
For the laser induced cutting of silicon materials a defocused Gaussian laser beam has been guided over the wafer
surface. In the course of this, the laser radiation caused a thermal induced area of tension without affecting the material
in any other way. With the beginning of the tension cracking process in the laser induced area of tension emerged a
crack, which could be guided by the laser radiation along any direction over the wafer surface. The achieved cutting
speed was greater than 1 m/s. We present results for different material modifications and wafer thicknesses. The
qualitative assessment is based on SEM images of the cutting edges.
With this method it is possible to cut mono- and polycrystalline silicon wafers in a very fast and clean way, without
having any waste products. Because the generated cracking edge is also very planar and has only a small roughness, with
laser induced tension cracking high quality processing results are easily accessible.