Selectively dry-etched In/sub 0.49/Ga/sub 0.51/P/In/sub 0.15/Ga/sub 0.85/As double doped-channel FETs using CHF/sub 3/+BCl/sub 3/ plasma

摘要

CHF/sub 3/+BCl/sub 3/ mixed-gas reactive ion etching process was used to study the etching characteristics of InGaP materials. After optimizing the etching conditions, we applied this technology to the gate-recess process of InGaP/InGaAs double doped-channel FET (DCFET) fabrication. The maximum transconductance of 180 mS/mm for a gate length of 1.0 /spl mu/m was obtained, and the cut off frequencies were f/sub i/=13 GHz and f/sub max/=30 GHz. InGaP/InGaAs DCFETs biased at class A demonstrated a power-added efficiency of 16.6%, a gain of 7 dB, and an output power density of 185 mW/mm at 1.9 GHz.