We report on our progress on the fabrication of AlGaN/GaN high electron mob
ility transistors (HEMTs) with extremely short gate length. AlGaN/GaN HEMTs
with different gate length from 6 mum down to 60 nm were fabricated to inv
estigate 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 im
proved 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 voltag
e on the gate length. (C) 2001 Elsevier Science B.V. All rights reserved.