Unraveling complex structures and properties of group IV alloys for mid-infrared technology

Unraveling complex structures and properties of group IV alloys for mid-infrared technology (Prof. Li)

graph depicting direct band gap on the y-axis and Sn composition on the x-axis. Short range order and Truly random order both decrease

Mid-infrared technology is crucial for a wide range of applications including night vision, chemical and biochemical sensing, and laser imaging. A promising candidate for the key materials enabling mid-IR imaging is group IV (SiGeSn) alloy, for its great capability of engineering bandgap as direct-to-indirect, near-to-mid IR wavelengths, significantly low radiative and Auger recombination coefficients for long carrier lifetime Si integration, and compatibility with CMOS. In this MURI project, Professor Li is collaborating with multiple institutions to develop high quality, stable SiGeSn alloys for lighter, faster, higher signal-to-noise, and more energy efficient devices as the next generation infrared imaging technology. To achieve this goal, fundamental materials science questions must be answered regarding the structure, stability, strain, defects, interfaces, and kinetics of the alloys. Professor Li’s group is building a multi-scale modeling framework that encompasses , Monte Carlo, machine learning, and advanced sampling method, to gain fundamental understanding of the materials and make predictions to guide experimental efforts. See Professor Li’s group website for more details.