NOISE PROPERTIES AND HETERO-INTERFACE TRAP IN SiGe-CHANNEL PMOSFETS

摘要

0.1-μm gate SiGe-channel (Ge fraction of 0-0.5) pMOSFETs with ultrashallow source/drain junctions formed by selective in-situ B-doped SiGe chemical vapor deposition has been fabricated, and their performance and short channel effects are discussed. Moreover, low frequency noise (LFN) and SiGe/Si hetero-interface trap density are evaluated using long-channel SiGe pMOSFETs. LFN in the pMOSFETs with a relatively wide range of Ge fraction x = 0.2, 0.5, 0.7, and SiGe thickness of 2-14 nm is investigated, and a relationship between the noise power in the SiGe channel and the maximum linear transconductance is discussed. Interface trap density in a SiGe/Si heterostructure is successfully measured using a low-temperature charge pumping technique, without interference from the interface traps between the gate oxide and the silicon surface. Correlation between the measured hetero-interface-trap density and the low frequency noise in the current flowing in the SiGe-channel is discussed.