Strain-induced changes in the gate tunneling currents in p-channel metal-oxide-semiconductor field-effect transistors

摘要

Changes in the direct gate tunneling current are measured for strained p-channel metal-oxide-semiconductor field-effect transistors (MOSFETs) on (100) wafers for uniaxial and biaxial stress. Decreases/increases in the gate tunneling current for various stresses primarily result from repopulation into a subband with a larger/smaller out-of-plane effective mass. Strain-induced changes in the valence band offset between Si and SiO_2 are also important but play a secondary role. Hole tunneling current is found to decrease for biaxial and uniaxial compressive stress and increase for biaxial tensile stress. The hole tunneling data is modeled using k·p self-consistent solution to Poisson and Schroedinger's equation, and a transfer matrix method.