A new two-step recess technology using SiN/sub x/ passivation and Pt-buried gate process and its application to 0.15 /spl mu/m Al/sub 0.6/InAs/In/sub 0.65/GaAs HEMTs

A new two-step recess (TSR) technology was successfully demonstrated using SiN/sub x/ passivation and Pt-buried gate process. Applying the developed two-step recess (TSR) process to the fabrication of 0.15 /spl mu/m Al/sub 0.6/InAs/In/sub 0.65/GaAs HEMTs, remarkable improvements could be obtained such as the suppression of the kink effect, and the increase of G/sub m,max/, f/sub T/ and f/sub max/. Since the side-recessed region was fully passivated by SiN/sub x/ dielectric layer, this TSR technology is also to offer additional advantage of good reliability.