Description: AdTech Photonics, in collaboration with the Center for Advanced Studies in Photonics Research (CASPR) at UMBC, is pleased to submit this Phase II proposal entitled 'High-Performance, Radiation-Hard, 2-D, Near-Infrared, Avalanche Photodiode Arrays' in response to NASA STTR 2004 program solicitation topics: T4.01 Earth Science Sensors and Instruments and T4.02 Space Science Sensors and Instruments. Our goal is to develop high performance avalanche photodiodes (APDs) and arrays with high sensitivity in the 1.06 µm and the near-infrared 1-1.6 µm wavelength ranges, which will be used in various NASA applications including interplanetary free space communications, remote sensing, 3-D lidar atmospheric, terrain, and vegetation studies from airborne, UAV, balloon, and space-borne platforms. All these applications will benefit from the improved sensitivity, photon counting rate, and radiation hardness, which will result from this research project.