We present a detailed high-pump-current study of self-heating effects in ultraviolet light-emitting diodes (LEDs) grown on sapphire. For deep ultraviolet LEDs on sapphire, our results establish self-heating to be a primary cause of premature power saturation under dc pumping. Even the flip-chip packaged devices undergo a steady-state temperature rise to about 70C at a dc pump current of only 50 mA (at 8 V) resulting in a significant decrease in LED output. Temperature rise values estimated from peak emission wavelength shifts and from micro-Raman mapping of the active devices were in good agreement.
|Translated title of the contribution||Self-heating effects at high pump currents in deep ultraviolet light-emitting diodes at 324 nm|
|Pages (from-to)||3491 - 3493|
|Number of pages||3|
|Journal||Applied Physics Letters|
|Publication status||Published - Sept 2002|
Bibliographical notePublisher: Amer. Inst. Physics