DC and RF performance of 0.25 mu m p-type SiGe MODFET

The DC and RF performance of a 0.25 mu m gatelength p-type SiGe modulation-doped field-effect transistor (MODFET) is reported, The hole channel consists of compressively strained Si0.3Ge0.7 layer grown on a relaxed Si0.7Ge0.3 buffer on a Si substrate, The combination of high-hole mobility, low-gate leakage current, and improved ohmic contact metallization results in an enhancement of the DC and RF performance. A maximum extrinsic transconductance (Gm(ext)) of 230 mS/mm was measured, A unity current gain cut-off frequency (fT) of 24 GHz and a maximum frequency of oscillation (f(max)) of 37 GHz were obtained for these devices.