ABSTRACT
Silicon technology has reached a very mature stage at which incremental progress is achieved with increasing difficulty. Further improvements in the performance of silicon ICs can be expected by using novel materials and device structures. The metal-oxide-semiconductor field-effect transistor structures described in this chapter use SiGe film thicknesses within the Mathews–Blakeslee critical thickness. The large valence band discontinuity and its monotonic increase with the Ge mole fraction are two of the most attractive features of the type I Si/SiGe alignment that can be used to control hole confinement in field-effect transistors and hole injection and electron transport in heterostructure bipolar transistors. For hole mobility that takes into account Ge fraction and doping density has been used in simulation. The process steps for generating the surface channel strained-Si channel p-MOSFET structure are performed in ATHENA. As a consequence, the current and voltage gain, unity gain cutoff frequency, and maximum frequency of oscillation can be optimized over wider voltage and temperature ranges.
