Many ongoing and future NASA lidar and altimetry systems and experiments use Nd:YAG lasers operating at 1064 nm. Single-element, reach-through silicon avalanche photodiode (APDs) are presently used as the optical detector at this wavelength. These systems could all benefit from the development of a low-noise, silicon-based imaging array technology with greater than 40% quantum efficiency at 1064 nm. The proposed innovation is based on using advanced materials and device designs to enhance the APD quantum efficiency at 1064 nm to greater than 60%. APD arrays will be fabricated and characterized for optical response, uniformity, dark current and noise performance. These photodetectors will have responsivity greater than 100 A/W and detectivity greater than 1E13 Jones at 1064 nm. This design will be scalable to sub-100 _m pixel dimensions and be compatible with wafer-level bonding to silicon CMOS readout and preamplifier integrated circuits.
