A novel Si/SiGe heterojunction pMOSFET with reduced short-channel effects and enhanced drive current

Abstract

A novel Si/SiGe bandgap engineered pMOSFET structure, called a high mobility heterojunction transistor (HMHJT), is proposed. Reduced short-channel effects and high drive current are predicted in this new device. Simulation results of devices with 100-nm physical gate lengths are presented. Physical effects are illustrated, and the performance is compared to the conventional Si devices. For low standby power or low leakage (high VT) applications, the off-state leakage current due to drain induced barrier lowering (DIBL) or bulk punchthrough is substantially suppressed, and a very high IonII0te ratio of 6 x 10T is obtained in a HMHJT without any anti-punchthrough implant. This ratio is a factor of 180 higher than that of a fabricated, conventional Si device with a similar threshold voltage found in the literature. On the other hand, for lower operating power (low VT) applications, an HMHJT has a drive current 80% higher compared to an optimized Si device, while satisfying the same criteria for the off-state leakage current. © 2000 IEEE.