Red Luminesecnce from Self-Assembled InAlAs/AlGaAs Quantum Dots with Bimodal Size Distribution
ZHOU Wei1, XU Bo1, XU Huai-zhe1, LIU Feng-qi1, GONG Qian1, JIANG Wei-hong1, SUN Zhong-zhe1, DING Ding1, LIANG Ji-bei1,WANG Zhan-guo1, ZHU Zuo-ming2, LI Guo-hua2
1Laboratory of Semiconductor Materials Science, 2National Laboratory for Superlittices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
Red Luminesecnce from Self-Assembled InAlAs/AlGaAs Quantum Dots with Bimodal Size Distribution
1Laboratory of Semiconductor Materials Science, 2National Laboratory for Superlittices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
Abstract：Red-emitting at about 640nm from self-assembled In0.55Al0.45As/Al0.5Ga0.5As quantum dots grown on GaAs substrate by molecular beam epitaxy are demonstrated. A doublepeak structure of photoluminescence (PL) spectra from quantum dots was observed, and a bimodal distribution of dot sizes was also confirmed by an atomic force micrograph (AFM) image for uncapped sample. From the temperature and excitation intensity dependence of PL spectra, it is found that the double-peak structure of PL spectra from quantum dots is strongly correlated to the two predominant quantum dot families. Taking into account the quantum-size effect on the peak energy, it is proposed that the high (low) energy peak results from a smaller (larger) dot family, and this result is identical to the statistical distribution of dot lateral size from the AFM image.
1999, Vol. 16 
