On the optimum design of the front-end PIN-heterojunction bipolar transistor optoelectronic integrated circuit photoreceiver

In this article, a detailed analysis of the performance of an integrated front-end PIN-heterojunction bipolar transistor photoreceiver has been given and optimum designs are suggested for maximum gain-bandwidth product (GB) and gain-bandwidth-sensitivity measure (GBS) of the device. The present SPICE-based analysis requires the equivalent circuit model of the receiver components. An expression for the impulse response of a PIN photodiode in the frequency domain has been derived to include the effect of transit time on the overall frequency response of the receiver. The models are verified with experimental data. Device parameters are tailored to obtain designs corresponding to maximum GB and GBS. These designs show much improvement in the performance when compared to the published results on unoptimized structures. Bandwidths greater than 40 GHz can be achieved using a simple three-stage amplifier circuit consisting of a common emitter and two emitter–follower circuits. Noise performance is calculated by minimum detectable power at a bit-error rate of 10−9 and the suggested optimum designs show improved noise performance.