Time Domain Analysis of Hole Trapping Effect in Avalanche Photodiode Using Schrödinger’s Equation

In this letter, a discrete matrix algorithm is proposed for hole-trapping effect analysis of avalanche photodiodes (APDs). Different from the previous thermionic emission model for the interface barrier between InGaAsP grading layer and InGaAs absorption layer, our model adds the particle's volatility into consideration. By analyzing the wave function of fast moving holes with Schrödinger's equation, the resonant tunneling effect has been discovered, which is closely related with the bias voltage and thickness of the grading layer. The influences of the whole shape of the barrier, including both height and width, on the impulse response have been investigated. Compared with previous simulation results, in our experimental study, the measured data agree better with the results from new model. Finally, to minimize the hole trapping effect for high speed operation of APDs, the optimal designs for InGaAsP grading layers are derived under different biases.