InGaAs/InP single-photon avalanche diodes performance variation with charge layer width and doping

In this letter, we have investigated the performance dependence of a planar-type Geiger-mode single-photon avalanche photodiodes (SPADs) on the multiplication and charge layer widths and doping. SPADs have great importance in the near infrared (NIR) wavelength range between 1.0 and 1.7 μm especially telecommunication wavelength. The planar SPAD was fabricated by standard chemical vapor deposition (CVD). Our results shows the width of the multiplication layer is critical parameter and tradeoff should be considered to modulate the dark current rate and photodetection efficiency. The fabricated SPAD with the multiplication width of 1.3 μm shows low enough dark current and high photocurrent. To prevent early breakdown at the periphery of the diode, guard rings and floating guard-rings were considered. The performance of the fabricated SPADs has been measured by a thermoelectric cooling system.