INGAAS/INALAS HEMT WITH A STRAINED INGAP SCHOTTKY CONTACT LAYER

We have fabricated a new structure of InGaAs/InAlAs HEMT's with a strained InGaP Schottky contact layer to achieve selective wet gate recess etching and to improve reliability for thermal stress. Strained In0.75Ga0.25P grown on InAlAs has been revealed to have sufficient Schottky barrier height for use as a gate contact Threshold voltage standard deviation has been reduced to one fifth that of a conventional InGaAs/InAlAs HEMT, as a result of successful selective recess etching. After thermal treatment at 300-degrees-C for 5 min, the drain current and transconductance did not change, while those of the conventional HEMT decreased by more than 10%.