Zusammenfassung
For Geiger-mode avalanche photodiodes, the two most important performance
metrics for most applications are dark count rate (DCR) and photon
detection efficiency (PDE). In 1.06-mu m separate-absorber-avalanche
(multiplier) InP-based devices, the primary sources of dark counts
are tunneling through defect levels in the InP avalanche region and
thermal generation in the InGaAsP absorber region. PDE is the probability
that a photon will be absorbed (quantum efficiency) times the probability
that the electron-hole pair generated will actually cause an avalanche.
A device model based on experimental data that can simultaneously
predict DCR and PDE as a function of overbias and temperature is
presented. This model has been found useful in predicting changes
in performance as various device parameters, such as avalanche layer
thickness, are modified. This has led to designs that are capable
simultaneously of low DCR and high PDE.
Nutzer