Analysis of InGaAs/InP Single-Photon Avalanche Diodes With the Multiplication Width Variation

This letter investigates dependence of performances of single-diffused single-photon avalanche photodiodes (SPADs) using a wet recess-etching technique on a multiplication width. Three-types of single-diffused InGaAs/InP planar SPADs with the different multiplication width have been fabricated and analyzed, which have no diffusion depth variation between fabricated devices. The fabricated SPAD with the multiplication width of 1.3 μm shows a low dark count rate (DCR) of 9 kHz with a photon detection efficiency of 17.1% at 240 K. It is found that the DCR is reduced by increasing the multiplication width.