W.-S. LourM.-K. TsaiK.-Y. LaiB.-L. ChenYING-JAY YANG2018-09-102018-09-102001-0402681242http://scholars.lib.ntu.edu.tw/handle/123456789/294640https://www.scopus.com/inward/record.uri?eid=2-s2.0-0035307203&doi=10.1088%2f0268-1242%2f16%2f4%2f301&partnerID=40&md5=d1aafdef7de86caa0bf0e31675daaa8dWe report a promising N+-InGaP/δ(P+)-InGaP/n-GaAs hetero-planar-doped barrier, which is used to fabricate both high-breakdown and self-aligned T-gate (SAT-gate) field-effect transistors (FETs). The characteristics of the devices and comparisons with previous reports are discussed. The enhanced conduction- and valence-band offsets associated with the new hetero-planar doped barrier show high-breakdown behaviour. In addition, high selective etching between InGaP and GaAs layers together with an ohmic gate allows the fabrication of a SAT-gate with a reduced gate-length of 0.8 μm. In the case of a high-breakdown FET, the drain-source breakdown voltage is as high as 32 V. In addition to competitive direct-current (dc) performances, a reduced knee voltage and improved frequency performances are obtained in SAT-gate FETs. The available unit-current-gain and unity-power-gain frequencies are, respectively, 19.5 and 30 GHz achieved as a 0.6 μm gate is obtained by forming a 1 μm metal gate. Furthermore, all the measured SAT-gate FETs exhibit high-linearity and high-performity dc and alternating-current performances.Etching; Field effect transistors; Semiconducting gallium arsenide; Semiconducting indium compounds; Semiconductor device structures; Semiconductor doping; Voltage measurement; Hetero planar doped structure; Indium gallium phosphide; Heterojunctionsjournal article10.1088/0268-1242/16/4/3012-s2.0-0035307203WOS:000168071200002