Analysis and Optimization of Modified Uni-Travelling-Carrier Photodiodes under High Optical Power Condition

We simulated back-illuminated mesa-structure Modified Uni- Traveling-Carrier Photo diodes (MUTC-PDs), using a simulator Apsys. The influence of space charge effect on the electric field distribution, carrier distribution and 3dB bandwidth are discussed in detail. An MUTC-PD with a bandwidth around 300GHz and an opto-electric responsivity of 0.16A/W are demonstrated by carefully optimizing the thickness of depleted absorption layer and adjusting the value of the reverse bias voltage under high optical power condition.