Comparison of strained SiGe heterostructure-on-insulator (001) and (110) PMOSFETs: C - V characteristics, mobility, and ON current

For the simulations of C -V characteristics and mobilities a homogenous channel HOI PMOS structure is simulated. The thicknesses of the top and bottom oxide are 1 nm and 10 nm, respectively. The thicknesses of the channel stack layers are t_sSi(cap) = 2 nm, t_sSiGe = 20 nm, and t_sSi = 4 nm. The thickness of the bulk layer below the bottom oxide is 800 nm. The Ge contents in the strained Si_1-zGe_z layer and in the relaxed Si_1-yGe_y virtual substrate are z = 0.46 and y = 0.25, respectively. A uniform donor doping concentration of 10¹⁵cm^-3 is assumed in in both the channel layers and the bulk Si region. A metal gate contact and an ohmic contact at the bottom of the bulk region are assumed. A bulk bias V_B of 0 V and a constant lattice temperature of 300 K are assumed in all simulations. The simulations are performed for the two interface orientations (001) and (110). The channel directions for the (001) and (110) interface orientations are [110] and [-110], respectively.