Multi-color VLWIR Focal Plane Array

We propose the development of high quality HgCdTe-based materials and high performance two-color detector arrays operating in the very-long wavelength infrared (VLWIR) spectral region. The fabrication of large format, high sensitivity focal plane arrays sensing in the VLWIR is highly desirable for various applications complementing Missile Defense, Army, Navy, and Air Force capabilities. They will improve the detection capabilities in all major MDA infrared systems either as separate arrays or when used together with current mid-wavelength (MWIR) or long wavelength (LWIR) infrared systems. Building on our current expertise, the first material system to be developed in this program will be a VLWIR detector based on HgCdTe alloys. Our current technology used for MWIR and LWIR detectors will be extended towards longer wavelengths. Improved material quality, new design architectures and new fabrication techniques will contribute to the success of this development effort. We also propose to develop HgTe/CdTe superlattice systems since they possess a number of desirable properties over both alloy HgCdTe and QWIP devices in the VLWIR region. Alloy and superlattice-based VLWIR detectors will be integrated into a multicolor system. We will use molecular beam epitaxy because it produces material of excellent quality and allows composition and doping control at atomic scale level over multiple epilayers in complex structures.