High-performance 0.1μm gate-length Ge/Si_0.4Ge_0.6 p-channel MODFETs

Results are reported of high-transconductance p-channel MODFETs fabricated on Ge/Sio_0.4Ge_0.6 strained-layer heterostructures grown by UHV-CVD. Devices with 0.1 mm gate length were fabricated on compressively-strained pure-Ge channels with a Hall mobility of 1750cm²/Vs (30900cm²/Vs) at room temperature (T = 77K). These devices displayed room-temperature peak extrinsic transconductances as high as 317 mS/mm, at V_ds = -0.6V, while the output conductance under the same bias conditions was only 18mS/mm, corresponding to a maximum voltage gain of 18. At T = 77K, peak extrinsic transconductances as high as 622 mS/mm were obtained at bias voltages as low as V_ds = -0.2V. To our knowledge, the 77K transconductance is the highest ever reported for a p-type field effect transistor.