Enhancement/Depletion Mode InGaP/AlGaAs PHEMT Process for High Efficiency Power Amplifiers

An integrated enhancement/depletion mode InGaP/AlGaAs power PHEMT process is demonstrated for various single- and dual-supply high efficiency power amplifiers. This technology utilizes excellent etch selectivity and surface charge screening properties of InGaP material. At 900 MHz D-mode PHEMT features output power density of 630 mW/mm with PAE=85% at 7 V, while E-mode PHEMT features PAE>70% from 2 to 7 V and high output power densities, especially at lower voltages.