Using our 0.2-mu m AlGaAs/GaAs/AlGaAs quantum well high electron mobility transfer (HEMT) technology, we have developed a chip set for 20-40 Gb/s fiber-optical digital transmission systems. In this paper we describe five receiver chips: a limiting amplifier with a differential gain of 17 dB and a 3 dB bandwidth of 29.3 GHz, a 40 Gb/s clock recovery, a data decision and a 1:4 demultiplexer, both for bit rates of more than 40 Gb/s, and a static 1:4 divider with operating frequencies up to 30 GHz. All presented chips were characterized on wafer with 50-ohm coplanar test probes.
