1304.5469 (Justin Iveland et al.)

Direct Measurement of Auger Electrons Emitted from a Semiconductor
Light-Emitting Diode under Electrical Injection: Identification of the
Dominant Mechanism for Efficiency Droop    [PDF]

Justin Iveland, Lucio Martinelli, Jacques Peretti, James S. Speck, Claude Weisbuch

We report on the unambiguous detection of Auger electrons by electron emission spectroscopy from a cesiated InGaN/GaN light emitting diode (LED) under electrical injection. Electron emission spectra were measured as a function of the current injected in the device. The appearance of high energy electron peaks simultaneously with an observed drop in electroluminescence efficiency shows that hot carriers are being generated in the active region (InGaN quantum wells) by an Auger process. A linear correlation was measured between the high energy emitted electron current and the "droop current" - the missing component of the injected current for light emission. We conclude that the droop phenomenon in GaN LED originates from the excitation of Auger processes.

View original: http://arxiv.org/abs/1304.5469