Third generation of infrared imagers demand performances for higher detectivity, higher operating temperature, higher resolution, and multi-color detection all accomplished with better yield and lower manufacturing costs. Antimonide-based gap-engineered Type-II superlattices (T2SLs) material system is considered as a potential alternative for Mercury- Cadmium-Telluride (HgCdTe) technology in all different infrared detection regimes from short to very long wavelengths for the third generation of infrared imagers. This is due to the incredible growth in the understanding of its material properties and improvement of device processing which leads to design and fabrication of better devices. We will present the most recent research results on Antimonide-based gap-engineered Type-II superlattices, such as high-performance dual-band SWIR/MWIR photo-detectors and focal plane arrays for different infrared regimes, toward the third generation of infrared imaging systems at the Center for Quantum Devices. Comparing metal-organic chemical vapor deposition (MOCVD), vs molecular beam epitaxy (MBE).
We have successfully fabricated 7-μm 155-nm-thick undercut microdisk cavities with AlN / Al0.60Ga0.40N (5.5 nm / 2.5 nm) multiple quantum wells epitaxially grown on Si substrate by metal–organic chemical vapor deposition. Upon optical pumping, whispering-gallery modes (WGMs) with wavelengths around ∼250 nm can be observed throughout the photoluminescence spectrum at room temperature, with quality factors around 500 to 1000. These cavity modes have been analyzed by theoretical calculations. Our results suggest great potentials to demonstrate WGM lasing in the UVC range from these AlGaN/AlN-on-Si microdisk cavities monolithically grown on a Si platform.