Induced stresses and structural changes in silicon wafers as a result of laser micro-machining

Abstract Laser micro-machining has proven to be a very powerful and successful tool for precision machining and micro-fabrication with applications in electronics, MEMS, medical, and biomedical fields. A large number of studies were devoted to the investigation of laser-based micro-machining covering the different aspects of the machining process. Induced stresses due to laser micro-machining process were, however, not fully investigated. In this paper, we report, for the first time, the results of utilizing micro-Raman spectroscopy as a powerful stress measurement technique in investigating stresses as well as structural changes induced in a silicon single crystal wafer as a result of laser micro-machining. It was found that laser machining of silicon wafers has induced tensile stress in the range 0.8–1.0 GPa. The machining process has also led to the creation of as much as 14% amorphous silicon in the machined area.