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High output InGaN single quantum well type blue and green light emitting diodes (LEDs) with an optical output of between 3 and 5 mW have been developed and commercialized. The differences in peak absorption energy and light emitting energy for the blue and green LEDs were 290 and 570 meV. These values indicate that the LED or laser emission is generated from a deep localized level in an InGaN well layer. An InGaN multiple quantum well laser diode was developed that oscillated continuously at room temperature for more than 300 hours. The preliminary characteristics are an output of 50 mW, an operating temperature of 100 °C, a characteristic temperature of 170 K, and an oscillation wavelength of 416 nm. © 1998 Scripta Technica, Electron Comm Jpn Pt 2, 81(5): 1–8, 1998 [ABSTRACT FROM AUTHOR]

By means of time-resolved emission spectroscopy, the emission dynamics of InGaN quantum well light-emitting devices is evaluated. The localization, radiation, and nonradiating recombination processes of the exciton are evaluated. It is found that there exist random potential fluctuations in the quantum well in samples with less than about 10% In in the InGaN activation layer. By means of these fluctuations, localization of the excitons can be attained. It is also found that the degree of localization increases as the In composition is increased, and that quantum dot-like regions are naturally formed in samples with an In content of more than about 20%. It is found that the capture of excitons by nonradiating recombination centers is suppressed and that a high-emission quantum efficiency is realized by such a pronounced localization. © 1998 Scripta Technica, Electron Comm Jpn Pt 2, 81(7): 45–56, 1998 [ABSTRACT FROM AUTHOR]