Small Pixel Hybridization (<5 um) for Infrared FPAs

ABSTRACT: Imaging applications such as persistent surveillance and tactical imaging require multi-megapixel imagers to achieve both high resolution and wide fields of view (FOV). Since the pixel size drives the size of the lens and other components in the optical train, the pixel size must be small in order to keep the size and weight of the entire imager manageable for different platforms. We propose to improve the hybridization process through a combination of processing and compression techniques to enable the reduction in ultimate pixel size to less than 5 microns. We will validate our process through test samples of silicon and infrared materials such as CdZnTe. At the end of this program, we will have demonstrated large sample hybridization with pixel pitch of 5 um or less. BENEFIT: The ability to hybridize small pixels (<5 um) in infrared materials will lead to further rounds of cost reduction of infrared FPAs because less material will be needed per die. The lower costs will lead to further deployment of infrared imagers across the services. In addition, commercial applications such as thermography will see lower costs and will therefore expand their market. In terms of performance, the smaller pixel will allow megapixel class imagers to be used in space-constrained applications such as gimbals. The added benefit is that the lens size can be reduced because the focal length of the lens decreases proportionally with pixel size.