SBIR Phase I: Novel AlGaN-based Structures for High-Efficiency and High-Power, Deep Ultraviolet Emitters

`This Small Business Innovation Research Phase I project is directed toward the development of a nitride-based semiconductor laser operating at 280 nm or shorter. In Phase I, high-efficiency and high power ultraviolet light emitting diodes (UV LED), incorporating novel AlGaN quantum-well (QW) structures, will be demonstrated as the proof of concept. The LED structure will overcome most of the current challenges in AlGaN-based UV emitters. These challenges include enhanced p-type doping of the cladding layer and reduction of the non-radiative recombination in the QW layer. The LED structure has unique advantage of transporting carriers through miniband of a short-period high-Al-fraction alloy superlattice. In this structure, the desired UV wavelength can be obtained by adjusting QW parameters such as well thickness and Al mole fraction. The research will be carried out by a joint effort consisting of the III-N molecular beam epitaxy (MBE) group and the semiconductor group. Semiconductor ultraviolet (UV) optical sources have a wide variety of applications in polymer curing, water purification, white light generation, projection displays, high-recording-density compact disk data storage, photolithography, biological agent detection, and non-line-of-sight covert communications