Summary form only given. The authors report the enhanced microwave performance of ion-implanted MESFETs fabricated on graded GaAs/AlGaAs heterostructures. Since low-noise MESFETs are typically biased at a low drain current, optimum low-noise operation requires high ft at low drain currents. ft values reported in the literature are generally measured close to Idss. This 0.5-μm gate heterojunction ion-implanted FET (HIFET) exhibits enhanced microwave performance, especially at low drain current, when compared to conventional ion-implanted GaAs MESFETs. At 20% of Idss, the current gain cutoff frequency ft is 40 GHz, which increases to 47 GHz at 50% of Idss. At 100% of Idss, the ft is 41 GHz. The maximum stable gain at 25 GHz of the HIFET is also 4 dB higher than that of the conventional MESFET.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering