Characteristics of AlₓIn 1−ₓAs ySb1− y (x:0.3−0.7) Avalanche Photodiodes

We report avalanche photodiodes fabricated from AlxIn1-xAsySb1-ywafers grown by molecular beam epitaxy using the digital alloy technique. A series of AlxIn1-xAsySb1-y(x = 0.3, 0.4, 0.5, 0.6, 0.7) p-i-n structures have been grown on GaSb substrate. Dark current, avalanche multiplication, excess noise, and external quantum efficiencies have been characterized. Very low excess noise, as characterized by k ~ 0.01-0.05, has been achieved.