Current-modulated electroluminescence spectroscopy was developed to investi
gate the mechanism of the current-induced spectral blueshift in InGaN singl
e-quantum-well blue and green light-emitting diodes. The evidence was obtai
ned that tail states exist in InGaN active layers, and also the blueshift w
as found to be dominated by the tail-state filling effect. (C) 2001 America
n Institute of Physics.