Role of grooving angle of 14-nm-InAs channel quantum well MOSFETs in improving analogue/RF and linearity performance

The authors investigate and physically analyse the effects of the angle of grooving (θ) on various analogues and RF parameters of InAs-channel quantum well MOSFETs with raised source/drain architecture at a 14-nm gate length. Moreover, harmonic distortion analysis is performed to examine the linearity and distortion of common source amplifiers built with such transistors. The findings reveal that the device with θ = 20° exhibits significant improvement in transconductance efficiency (gm/IDS), output resistance (rd), and voltage gain (Av) while showing degradation in transconductance (gm) compared to the corresponding parameter with θ = 90°. Furthermore, the obtained results manifest that the total harmonic distortion drops to −47 dB for an amplifier built with the device having θ = 90° compared to −22 dB obtained with θ = 20°. Notably, as the angle of grooving increases from 20° to 90°, the gain bandwidth of the amplifier improves by 232% while the peak gain falls by 40%.