Monolithic PIN-HEMT photoreceiver integration

In current telecommunications systems, there is a strong need to increase the data rate. The next generation of optical communication systems will operate at 40 Gb/s. As high-speed receivers for such systems, monolithic photoreceiver OEICs are very attractive, because of their potential for lower parasitics and higher performances compared to hybrid approaches. We report here the monolithic integration of a InP[Zn]/GaInAs/InP[Si] PIN photodiode with GaInAs/InP composite channel HEMTs. The PIN-HEMT structure is grown by single-step LP-MOVPE on pre-recessed semi-insulating InP substrate. This quasi-planar integration scheme allows a standard microelectronics processing. The 0.1 μm T-shape HEMT gates are defined by e-beam lithography, as close as 70 μm to the 3 μm deep photodiode pockets. As a preliminary result, a 4-channel receiver OEIC has photodiodes with 0.8 A/W responsivity, 30 nA dark current at -10 V, two-stage amplifiers with 20 to 28 dB gain and a bandwidth of 3 GHz