Short-channel effects in AlGAN/GaN HEMTs

We report on our progress on the fabrication of AlGaN/GaN high electron mobility transistors (HEMTs) with extremely short gate length. AlGaN/GaN HEMTs with different gate length from 6 μm down to 60 nm were fabricated to investigate DC- and high frequency behavior as well as short channel effects. We have found that the transistors with gates in the 100 nm range can be improved in the device performance with respect to transconductance and high frequency but also shows short channel effects as the loss of saturation in the output characteristics and a strong dependency of the threshold voltage on the gate length.