Effect of Small-Angle Grain Boundary on the Mechanical Properties in Direct Silicon Bonded Wafer

摘要

The mechanical properties of small-angle grain boundary (GB) in directrnsilicon bonded wafer are investigated by dislocation motion using thernVickers micro-indentation combined with nano-indentation technique. Therndislocation motion is thoroughly hampered at the GB, due to the largernstrain field (comprehensive stress as high as ≈339MPa), which isrndemonstrated by the micro-Raman spectroscopy measurement. Nanoindentationrntests directly on GB show that Young’s modulus and hardnessrnare almost identical to those in the grain. The results indicate thatrnelectrically active small-angle GB with high stress should not be the weakrnpoint of mechanical strength in multi-crystalline silicon.