EXPERIMENTAL STUDY AND SIMULATION OF STRESS-INDUCED CAVITIES IN SILICON

摘要

The formation of cavities on the surface of silicon wafers under nitride films with high tensile stresses has been studied experimentally and by means of computer simulations. For the first time, the development of stress-induced trenches is reported. The simulations indicated that generation and recombination of point defects under stresses at the wafer surface might lead to the essential mass transfer of silicon from areas of high pressure. Stress-induced surface diffusion of silicon atoms was a dominating mechanism of the cavity growth. From the performed experimental calibration of the simulation model, the values of 10"' cm /s and 0.9 eV were extracted for the pre-exponential and activation energy of the self-diffusion coefficient on the silicon surface.