Mechanical properties of a micron-sized SCS film in a high-temperature environment

The effects of varying temperature on the mechanical properties of a micron-sized single-crystal silicon (SCS) film were investigated using an 'on-chip' tensile test. Young's modulus slightly decreased as the test temperature increased from room temperature (RT) to 500 °C. Furthermore, the fracture stress at 500 °C decreased to 1.84 GPa, which is about 32% of that at RT. The stress–strain relationship of the SCS film at 400 °C and 500 °C showed elastic–plastic deformation, and SEM images showed crossed slip lines on the side surface of the fractured specimen. From the measured stress–strain relationship, plastic strain in micron-sized silicon seems to have occurred at temperatures lower than the brittle-to-ductile transition temperature in bulk silicon.