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Title: Normally-ON/OFF AlN/GaN High Electron Mobility Transistors

Journal Article · · Physica Status Solidi C

We report on the novel normally-on/off AlN/GaN high electron mobility transistors (HEMTs) grown by plasma-assisted molecular beam epitaxy. With simple oxygen plasma exposure, the threshold voltage can be tuned from -2.76 V to +1.13 V depending on the treatment time. The gate current was reduced and gate current-voltage curve show metal-oxide semiconductor diode-like characteris-tics after oxygen plasma exposure. The extrinsic trans-conductance of HEMTs decreased with increasing oxy-gen plasma exposure time due to the thicker Al oxide formed on the gate area. The unity current gain cut-off frequency, fT, and the maximum frequency of oscillation, fmax, were 20.4 GHz and 36.5 GHz, respectively, for a enhancement-mode HEMT with the gate dimension of 0.4 100 m2.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
Sponsoring Organization:
USDOE Office of Science (SC)
DOE Contract Number:
DE-AC05-00OR22725
OSTI ID:
984379
Journal Information:
Physica Status Solidi C, Vol. 7, Issue 10; ISSN 1862-6351
Country of Publication:
United States
Language:
English