AlGaN/GaN HEMT on Si (111) substrate for millimeter microwave power applications

This paper reports the capability of AlGaN/GaN HEMTs on Si (111) substrates for microwave power applications above 30 GHz. A current gain cut-off frequency f
_t
=90 GHz and a maximum power gain cut-off frequency f
_max
=135 GHz are obtained for a 80 nm gate-length transistor. These results, associated with low lag effects, demonstrate the capability of these transistors for high performance, cost effective, MMIC fabrication on a Si substrate for high frequency microwave power applications.