Analysis of carrier mobility change in silicon inversion layer due to through-silicon via thermal stress

The effect of stress concentration around Cu through-silicon via (TSV) on carrier mobility in typical metal oxide semiconductor field effect transistor (MOSFET) Si inversion layer is considered by using numerical finite element simulation in combination with piezoresistive equations. Carrier mobility changes along <;100>; or <;110>; channel directions are obtained for transistors on (001) Si die, and for devices fabricated with either strain-Si or unstrained-Si technology. The analysis shows that the TSV related thermal stress causes a higher mobility shift in p-MOSFET with <;110>; channels.