Indium gallium arsenide avalanche photodiodes... not just for telecom anymore

Continual advances in III-V semiconductor growth and processing technologies are bringing devices that were once considered exotic into the mainstream. Here we discuss the design and fabrication of InGaAs avalanche photodiodes that are produced with yields approaching that of PIN photodiodes, enabling optical receivers that achieve 8-10 dB better sensitivity than their PIN diode counterparts. In addition to driving cost down, the high die yield enjoyed by current designs enable new applications using 1D and 2D arrays of devices such as imaging laser radar. The availability of inexpensive control circuits that are used for APD bias and temperature compensation makes the widespread use of these detectors extremely practical.