Analytic model for the efficiency droop in semiconductors with asymmetric carrier-transport properties based on drift-induced reduction of injection efficiency

作者：Lin Guan Bo^*; Meyaard David; Cho Jaehee; Schubert E Fred; Shim Hyunwook; Sone Cheolsoo

来源：Applied Physics Letters, 2012, 100(16): 161106.

DOI：10.1063/1.4704366

• carrier density
• carrier mobility
• gallium compounds
• III-V semiconductors
• indium compounds
• light emitting diodes
• p-n junctions
• wide band gap semiconductors

An analytic model is developed for the droop in the efficiency-versus-current curve for light-emitting diodes (LEDs) made from semiconductors having strong asymmetry in carrier concentration and mobility. For pn-junction diodes made of such semiconductors, the high-injection condition is generalized to include mobilities. Under high-injection conditions, electron drift in the p-type layer causes a reduction in injection efficiency. The drift-induced leakage term is shown to have a 3rd and 4th power dependence on the carrier concentration in the active region; the values of the 3rd-and 4th-order coefficients are derived. The model is suited to explain experimental efficiency-versus-current curves of LEDs.

• 出版日期2012-4-16