A monolithically integrated In/sub 0.53/Ga/sub 0.47/As optical receiver with voltage-tunable transimpedance

Abstract
The authors report the fabrication and performance of the first monolithically integrated In/sub 0.53/Ga/sub 0.47/As receiver with voltage-tunable transimpedance. In this receiver, a SiN/sub x/ passivated p-i-n diode is integrated with an In/sub 0.53/Ga/sub 0.47/As transimpedance amplifier using multiple-etched steps to assist lithography and step coverage of the interconnection metallization. The p-i-n diode has an external quantum efficiency of 82% at a wavelength of 1.3 mu m and -5 V bias. Adjusting the gate bias of a narrow-gate feedback transistor gives the receiver a tunable transimpedance of 19-36 Omega , a responsivity of 17-30 kV/W, and an unequalized bandwidth of 90-130 MHz.