Review Of Recent Developments In Lightwave Devices

The structure and device properties of long wavelength lightwave devices - including, indium gallium arsenide (InGaAs) pin photodiodes and avalanche photodiodes (APDs) - are described. Quantum efficiencies above 85% at 1.54 um, dark current densities near 1 uA/cm/sup 2/ (-5V, 300K) and 3 mm diameter shunt resistancies (10 mV, 300K) above 10 megohms have been observed. Avalanche gains above 20 have been measured with multiplied primary dark currents below 7 nA. Extended wavelength In/sub x/Ga/sub 1-x/As (.53 < x < .80) pin detectors are also described with 70% quantum efficiency and room temperature RoA products above 2000 ohm -cm/sup 2/ at 1.8 um, 900 ohm -cm/sup 2/ at 2.1 um and 15 ohm -cm/sup 2/ at 2.6 um.