MOSFETs with ultrashallow junction and minimum drain area formed by using solid-phase diffusion from SiGe

An advanced CMOS structure, in which a raised source/drain and contact wind ows formed over the field oxide, was fabricated, Ultrashallow junction form ation using solid-phase diffusion from doped SiGe layers was used to fabric ate MOSFETs. These MOSFETs demonstrated excellent short-channel characteris tics and 70%-80%-reduced parasitic drain-junction capacitance, They have ul trashallow junctions with a depth of 25 nm and a low source/drain extension (SDE) resistance: 350 Omega /sq (NMOSFETs) and 390 Omega /sq (PMOSFETs). T he isotropic diffused SDE structure was formed by using solid-phase diffusi on, which could effectively form a shallow junction and a suitable overlap between gate and SDE:, This structure results in good short-channel charact eristics and high current drivability.