GaAs1-xSbx1.06 µm avalanche photodiodes

Progress toward achieving high gain, avalanche photodiodes operating at 1.06µm is described. 1.06µm photodiodes have been fabricated (3 mil × 3 mil) with average gain of >14 at a leakage current of 150 na. These devices are fabricated from GaAs1-xSbxmaterial grown by LPE on GaAs substrates. Multiple layer step graded structures are used to reduce stress in the active layers. A self-terminated depletion region design has been found to give significant improvement in gain uniformity.