ABSTRACT
Recently, metamorphic InGaAs/InAlAs HEMTs on GaAs substrate have received the attention due to their potential for comparable performance, with the advantages of low cost and process facility of GaAs-based substrate, as compared with InP-based HEMTs. Several groups have demonstrated that the device performance of GaAs-based MHEMTs is comparable to those of InP-based devices. They obtained current gain cutoff frequency (fT) values of 225 [3], 260 [4], 293 [5], and 350 [6] GHz. The fj characteristics of the reported 100 nm or sub 100 nm gate HEMT devices should be apparent that high frequency performance o f GaAs MHEMTs is essentially equal to those o f the InP HEMT.
