SHORTWAVE SEMICONDUCTOR LASERS: Lattice constant is key to group III-nitride-based UV light emitters

摘要

While progress is being made in the development of semiconductor UV lasers and LEDs, their external quantum efficiency remains low. One potential solution could be application-oriented nitride substrates, which have tailored compositions that achieve lattice matching. Efforts to harness the benefits of UV radiation have been given a boost as a result of rapid progress in the synthesis of group III-nitride materials. The nitride materials are wide-bandgap semiconductors that can be used to fabricate light-emitting devices in the UV region of the electromagnetic spectrum. They can also be used for light detection in the same spectral band. The majority of efforts are focused on the fabrication of UV light emitters: both lasers and LEDs. The most important and interesting applications of the light emitters include disinfection and sterilization of surfaces and utensils, water disinfection and decontamination, UV curing processes in industry, phototherapy, and medical diagnostics.