Temperature effects on fracture behavior of notched silicon film specimen

We performed tensile tests on single-crystal-silicon film at temperatures ranging from RT (room temperature) to 600°C. We made notched specimens by using a focused ion beam (FIB) process. The fracture toughness did not change from room temperature to 60°C. However, between 60°C and 80°C, it rapidly increased to almost double that at room temperature, and it saturated at temperatures higher than 80°C. Some specimens tested at 150°C and 300°C showed the nonlinear relationships between stress and strain. Shapes of the fractures that occurred from 80°C to 600°C were clearly different from the fracture shape at 60°C. These results suggest that dislocation motion occurred even at low temperatures near 80°C.