Monolithic integration of a GaInAs PIN photodiode and AlGaAs/GaAs/AlGaAs HEMTs on GaAs substrate

A monolithic integrated optoelectronic receiver for a wavelength of 1.55 μm consisting of a GaInAs PIN diode and a transimpedance AlGaAs/GaAs HEMT amplifier has been fabricated. The available technology includes three etch processes, five metal lift-off processes, an oxygen implantation for device isolation, two dielectric layers of SiN and an electroplated gold interconnection layer. The gate levels for enhancement and depletion FETs were carried out using e-beam lithography with gate lengths of 0.3 μm. The responsivity of the photodiodes is 0.40 A/W, and the photoreceiver has a -3 dB bandwidth of 6.9 GHz. Clear and open eye diagrams for a 10 Gbit/s optical data stream have been obtained. At this data rate the sensitivity of the photoreceiver is better than -17.5 dBm (BER=10^-9). The yield of this circuit is better than 80% realized on 2´´ wafers