A resonant-cavity, separate-absorption-and-multiplication, avalanche photodiode with low excess noise factor

We report on the design, fabrication, and performance of a photodiode that combines the advantages of a resonant cavity with a separate-absorption-and-multiplication avalanche photodiode. The device is grown on GaAs using molecular beam epitaxy and is designed to detect light near 900 nm. This photodetector has exhibited the following characteristics: an external quantum efficiency of 70%, a spectral linewidth of less than 7 nm, an avalanche gain in excess of 30, and low dark current. In addition, a low excess noise factor corresponding to 0.2/spl les/k/spl les/0.3 has been achieved.