A high-speed monolithic optoelectronic receiver consisting of a photodetector, a transimpedance amplifier and a 50- OMEGA output buffer stage has been fabricated using an enhancement/depletion 0. 35- mu m recessed-gate GaAs MESFET process. The interdigitated metal-semiconductor-metal (MSM) photodetector has a dark current of 0. 8 nA, a responsivity of 0. 2 A/W, and a capacitance of 12 fF. The bandwidth of the receiver is 5. 2 GHz with an effective transimpedance of 300 OMEGA into a 50- OMEGA load, which corresponds to a transimpedance bandwidth product of 1. 5 THz- OMEGA .