In0.7Ga0.3As quantum-well MOSFETs with record gm and effective mobility

In this paper, we have fabricated and characterized In0.7Ga0.3As quantum-well (QW) MOSFETs with bilayer Al2O3/HfO2 gate stack, grown by ALD. The fabricated device with L-g = 4 mu m exhibits excellent maximum transconductance (g(m)_(max) ) in excess of 0.5 mS/mu m, together with reasonably good electrostatics integrity, such as DIBL < 45 mV/dec and subthreshold swing < 110 mV/dec. In addition, we have modeled a trend of g(m)_(max) as a function of L-g, and benchmarked g(m) characteristics of our InGaAs MOSFETs against other reports, revealing that the value of g(m) demonstrated in this work is the highest among any other devices with similar values of L-g. In trying to understand how such performance comes from, we have extracted effective mobility, where the mobility in our devices is as high as 6,600 cm(2)/V-s at 300 K.