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A new self-aligned gate process employing combined metallisation techniques has been developed and applied to pseudomorphic InAlAs/InGaAs HEMT structures. An asymmetric V-shaped gate defined by electron-beam lithography using a multi-level composite resist was lifted-off after sequential W sputtering and Ti-Au evaporation. Ohmic metals were directly evaporated on to the waver to be self-aligned with the gate. The 0.25 mu m gate length FET's showed a transconductance in excess of 1150 and 1350 mS/mm at 300 and 77 K, respectively.