Present Status of Deep UV Nitride Light Emitters

Ultraviolet light emitting diodes with emission wavelengths less than 400 nm have been developed using the AlInGaN material system. Rapid progress in material growth, device fabrication and packaging enabled demonstration of deep-UV light-emitting devices with emission from 400 to 210 nm with varying efficiencies. For high aluminum alloy compositions needed for the shorter wavelength devices, these materials border between having material properties like conventional semiconductors and insulators, adding a degree of complexity to developing efficient light emitting devices. This chapter provides a review of III-nitride based UV light emitting devices including technical developments that allow for emission in the ultraviolet spectrum, and an overview of their applications in optoelectronic systems.