Abstract: Avalanche photodetector devices and methods of use thereof are provided that incorporate deep levels to increase secondary carrier generation via impact ionization under application of a reverse bias. An avalanche photodetector device may include p+ and n+ regions, an intermediate semiconductor absorption region provided therebetween, and at least one semiconductor region residing between the p+ and n+ regions that incorporates deep levels. When light is incident on the device such that the absorption depth of the light extends into the intermediate semiconductor absorption region, a photocurrent is produced under a reverse bias includes both photocarriers generated within the intermediate semiconductor absorption region and secondary carriers released from the deep levels via impact ionization.

Abstract: Avalanche photodetector devices are disclosed in which spatial asymmetry is employed to preferentially enhance avalanche multiplication of electrons. In some example embodiments, an avalanche photodetector device includes p-doped and n-doped regions and a central waveguide region, where the p-doped region is laterally offset from the central waveguide by a first lateral offset region, and where the n-doped region is laterally offset from the central waveguide by a second lateral offset region. The first and second lateral offset regions are asymmetrically defined such that impact ionization and avalanche multiplication of electrons in the second laterally offset region is enhanced relative to that of holes in the first laterally offset region. In some example implementations, the asymmetry may be provided by a difference in relative heights and/or lateral spatial extends (widths) of the lateral offset regions, such that the electric field, or a spatial extent associated therewith, is enhanced for electrons.