InGaAsN absorber for telecommunication wavelength APDs

We demonstrate the InGaAsN PIN structures grown by MBE with photoresponse of approximately 1.3 μm and optimized by post growth annealing. The assessment of the annealing study was carried out by comparing the dark current density and photocurrent spectra of the as-grown and annealed samples. The dark current for an optimally annealed InGaAsN PIN is approximately 2 μAcm^-2 at an electric field of 100 kVcm^-1. Pure electron-initiated and mixed electron-hole initiated photo-multiplication measurements on the InGaAsN pin diodes indicate electrons and holes have nearly equal probability of initiating ionization events. Finally, the design of a separate-absorption-charge-multiplication (SACM) avalanche photodiode (APD) design using InGaAsN as the absorber and Al_0.8Ga_0.2As as the multiplication layer were discussed.