Room and Cryogenic Temperature Operation of 280 nm Deep Ultraviolet Light Emitting Diodes

We present a study of the electrical and optical characteristics of 280 nm emission deep ultraviolet light emitting diodes (LED) at room and cryogenic temperatures. At low bias the defect assisted carrier tunneling primarily determines the current conduction. The room-temperature spectral performance and optical power are limited mostly by pronounced deep level defect assisted radiative and non-radiative recombination as well as poor electron confinement in the active region. At temperatures below 100 K the electroluminescence peak intensity increases by more than one order of magnitude due to suppression of non-radiative recombination channels indicating that with a proper device design and improved material quality, milliwatt power 280 nm LED are viable.