Sensors Unlimited, a Raytheon Company

Sensors Unlimited Inc. (SUI), a Raytheon Company, has developed high-speed, short-wave infrared (SWIR) focal plane arrays (FPA) to meet the increasing field-of-view (FOV) and bandwidth requirements for simultaneous laser pulse detection and imaging applications such as LiDAR. Modifications to SUI’s standard InGaAs photodiode array (PDA) designs, including junction shape, dielectric passivation design, and hybridization bump shape and contact metallization were performed to achieve total effective capacitance reduction. These modifications have been demonstrated to reduce by over 50% the effective capacitance load at the detector and readout integrated circuit (ROIC) while preserving the company’s industry-leading low dark current resulting from its proprietary epitaxial structure design. The design improvements can be applied to both high-speed P-I-N photodiode arrays and Avalanche Photo Diodes (APD) arrays. In both cases the presented design provides for achieving the best camera performance in applications such as low-light imaging, coded-pulse tracking and laser range-finding. The modifications can also be applied to bump-bonded 1-D (linear) https://www.sensorsinc.com/technology/publications/