N-CHANNEL SI/SIGE MODFET - EFFECTS OF RAPID THERMAL-ACTIVATION ON THE DC PERFORMANCE

Si/SiGe MODFET's with P- and As-implanted source and drain contacts have been fabricated. The effect of rapid thermal activation (RTA) on the dc performance of those devices was studied for the first time. The RTA temperature determines the device operation, i.e., a 550-750-degrees-C treatment yields enhancement and a 900-degrees-C annealing results in depletion mode. Extremely high ratios of the 77- to the 300-K transconductance (almost-equal-to 4.5) were found. Low thermal budget RTA (almost-equal-to 600-degrees-C) is essential to eliminate degradation of the channel mobility and to achieve a significant increase of the 77-K transconductance.