LIDAR SYSTEM WITH LOW-NOISE AVALANCHE PHOTODIODE

摘要

In one embodiment, a lidar system includes a light source configured to emit an optical signal and a receiver configured to detect an input optical signal that includes a portion of the emitted optical signal scattered by a target located a distance from the lidar system. The receiver includes an avalanche photodiode (APD) configured to receive the input optical signal and produce a photocurrent signal corresponding to the input optical signal. The APD includes a multiplication region that includes a digital-alloy region that includes two or more semiconductor alloy materials arranged in successive layers. The digital-alloy region is configured to produce at least a portion of the photocurrent signal by impact ionization. The receiver is configured to determine, based on the photocurrent signal produced by the APD, a round-trip time for the portion of the emitted optical signal to travel to the target and back to the lidar system.