AlInSb Mid-Infrared LEDs of High Luminous Efficiency for Gas Sensors

In this paper, performance of mid-infrared light emitting diodes (LEDs) with an InSb buffer layer and AlInSb active/barrier layers, emitting at room temperature is reported. This film structure makes an ideal base material in view of carrier confinement and crystalline quality. In order to achieve a high efficiency for light extraction, backside emission architecture is adopted together with a rough emitting surface and TiO2 anti-reflection coating. The resulting AlInSb LED shows 75% higher power conversion efficiency than the reference, which has the highest efficiency in the market to date.