It is difficult to cut low-k materials with ordinary diamond cutter wheel, because the direct action of diamond cutter wheel will lead to splash and bad appearance of low-k materials, such as collapse, crack, passivation, metal layer uplift and so on. Therefore, it is necessary to remove the low-k layer on the surface of the silicon wafer by laser first, and then cut the substrate materials such as silicon with a knife wheel.

The main way to remove the low-k layer is to use laser grooving technology, which shapes the light spot into a specific shape through the optical path system, focuses the laser on the surface of the material to achieve a specific groove shape, and instantly evaporates the low-k layer by using ultra-fast laser with extremely high peak power without intermediate process, thus greatly reducing the heat affected zone. It is an advanced laser "cold" processing technology.