InAlGaAs Staircase Avalanche Photodiodes

Abstract
Metal-organic vapor phase epitaxy (MOVPE)-grown InAlGaAs staircase avalanche photodiodes (APDs) with sawtooth graded-gap multiplication regions are demonstrated for the first time. Extremely high multiplication factors M of over 100, low dark currents of 550 nA at M=20, and high-gain-bandwidth products exceeding 100 GHz were confirmed in 10×200- Å sawtooth multilayer APDs.