Addressable Monolithic InSb on GaAs Focal Plane Arrays for MWIR Imaging

Mid-wave infrared sensing and imaging is of growing importance for the detection of environmental greenhouse gases such as CO2 and CH4. The ability to survey large infrastructure in addition to making single point measurements will bring many advantages to industrial asset management in particular. Existing technology for MWIR imaging relies on costly flip chipped technology and cryogenic cooling. We have investigated a monolithic integrated technology that can be made in a traditional planar process and operates at room temperature. By growing III-V wafers with a GaAs transistor layer and an InSb photodetection layer we are able to eliminate the need for a two-chip solution and the complex fabrication steps traditionally required. We present the method for making monolithic sensors and preliminary results demonstrating the imaging and gas sensing capabilities of the new technology.