Journal of Vacuum Science & Technology B, Vol.23, No.3, 966-969, 2005
Cross sections for the investigation of the electroluminescence excitation of InGaN/GaN quantum wells in blue light-emitting diodes with multiquantum barriers
Cross sections of the electroluminescence (EL) excitation of InGaN/GaN multiquantum wells (MQWs) in blue light-emitting diodes (LEDs) with multiquantum barriers (MQBs) have been investigated. It was found that a device with an MQB structure exhibited a higher quantum efficiency, as well as higher temperature insensitivity, compared with the conventional MQW LEDs. A total cross section of 5.3 x 10(-15) cm(2) was obtained for the MQB QWs, by fitting them to the measurement of the spectral intensity at room temperature; the value was 4.5 X 10(-15) cm(2) for those devices with GaN barriers. Not only the EL excitation cross section for active region, but also the abnormal quantum efficiency evolutions were found to be a function of temperature. Moreover, they were in good agreement with the rate equation model. (c) 2005 American Vacuum Society.