VARIATIONS OF RESONANT TUNNELING PROPERTIES WITH TEMPERATURE IN STRAINED SI1-XGEX/SI DOUBLE-BARRIER STRUCTURES

We have investigated the resonant tunneling feature variations with temperature in molecular beam epitaxy grown strained Si0.78Ge0.22/Si double-barrier structures with different well width w and spacer thickness L(s). Both w and L(S) have strong effects on the temperature characteristics of the peak current J(P), the valley current J(V), and the current peak-to-valley ratio (PVR). When w is reduced, both J(P) and J(V) are greatly increased. The resonant tunneling devices (RTDs) also have better temperature stability and PVR decreases slower. The RTD with larger L(S) has higher peak current. Beside w and L(S), the quasi-Fermi level position has a very important influence on the resonant tunneling feature variations, which is stressed in the present work.