A Recessed - Gate In , . 52 A 10 . 48 As / n + - 1 % . 53 G % . 47 A ~ MIS - type FET

Scaling of the Ino,52AI,,,,As insulator thickness of In,,~s2AI,,1,As/n+-Ine,s3Gao.J,As MIS-type FET’s is found experimentally to result in a drastic drop in performance below 200 A. This is demonstrated to arise from an increase in the sheet resistance of the extrinsic portions of the device that accompanies insulator scaling. In order to solve this problem, a recessed-gate MISFET with a very thin (300 A ) n+-Ino.s3Gao,4,As cap layer has been fabricated. A 1.5-pnlong gate device showed a transconductance of 285 mS/mm and a current-gain cutoff frequency of 19.4 GHz. This result proves the ability of a thin n+-lno.s3Gae.47As cap to reduce source resistance and improve device performance. The fabricated recessed-gate structure is a promising candidate for high-performance-scaled MIS-type FET’s based on thin, heavily doped In,,,53Gao.47As channels.