A compact and wideband GaAs P-HEMT distributed amplifier IC based on a micro-machined CPW

This paper presents a new GaAs P-HEMT distributed amplifier IC that employs a micro-machined, grooved-CPW. By removing the substrate between the signal and ground metal, the grooved-CPW has small effective dielectric constant (/spl epsi//sub r,eff/) and becomes a highly inductive line. When the grooved-CPW is used in the distributed amplifier, the f/sub 3dB/ and the chip size have been improved by about 20%. The fabricated GaAs P-HEMT distributed amplifier IC has a gain of 10 dB with f/sub 3dB/>50 GHz.