Fabrication of a 120 nm gate-length lattice-matched InGaAs/InAlAs InP-based HEMT

A new PMMA/PMGI/ZEP520/PMGI four-layer resistor electron beam lithography technology is successfully developed and used to fabricate a 120 nm gate-length lattice-matched In0.53Ga0.47As/In0.52Al0.48As InP-based HEMT,of which the material structure is successfully designed and optimized by our group.A 980 nm ultra-wide T-gate head,which is nearly as wide as 8 times the gatefoot (120 nm),is successfully obtained,and the excellent T-gate profile greatly reduces the parasitic resistance and capacitance effect and effectively enhances the RF performances.These fabricated devices demonstrate excellent DC and RF performances such as a maximum current gain frequency of 190 GHz and a unilateral power-gain gain frequency of 146 GHz.