Physical Understanding of Fundamental Properties of Si (110) pMOSFETs Inversion-Layer Capacitance, Mobility Universality, and Uniaxial Stress Effects

Fundamental transport properties of Si (110) pMOSFETs are systematically investigated. Inversion-layer capacitance (inversion-layer thickness) of (110) pFETs is larger (smaller) than that of (100) pFETs owing to larger effective mass normal to the surface in (110) pFETs. Peculiar substrate impurity concentration (N_sub) dependence of low-field mobility (mu) : mu increase with N_sub increase in (110)/<110> pFETs, is observed for the first time. High mu even in high N_sub regime in (110) pFETs is caused by large subband energy splitting. Although uniaxial stress effects on mu is weaker in high-N_sub (110) pFETs than in (100) pFETs, much higher mu without strain leads to excellent performance of strained (110)/< 110> pFETs.