High-performance 0.1 μm gate-length Ge/Si0.4Ge0.6 p-channel MODFETs

Results are reported of high-transconductance p-channel MODFETs fabricated on Ge/Si_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 1750 cm²/Vs (30900 cm²/Vs) at room temperature (T=77 K). These devices displayed room-temperature peak extrinsic transconductances as high as 317 mS/mm, at V_ds=-0.6 V, while the output conductance under the same bias conditions was only 18 mS/mm, corresponding to a maximum voltage gain of 18. At T=77 K, peak extrinsic transconductances as high as 622 mS/mm were obtained at bias voltages as low as V_ds=-0.2 V. To our knowledge, the 77 K transconductance is the highest ever reported for a p-type field effect transistor