Researching for New Quantum Optoelectronic Properties by Disorderly Stacked-Layer of Disordered Quantum Dots

(1)从理论上推导了晶格常数与半导体衬底晶格常数不同的半导体层异质外延生长时开始自然形成量子点的最大生长层厚度。理论计算结果与InAs/GaAs、InP/GaP、ANS SiGe/Si的实验结果吻合较好。(2)实验确定了InAs/GaAs量子点叠加层的最佳GaAs层厚度。(3)在自发有序的GaInP/GaAs中观察到了导致发光强度增强和发光峰红移的无序效应。(发表在《应用物理杂志》上)虽然在无序矩阵中的有序态观察到了发光增强和红移，但这种现象可以用有序矩阵中的无序态的影响来解释。(4)w…中的无序量子线线宽、厚度和成分越杂乱，就会表现出发光增强和红移的效果。(发表在《应用物理快报》上)(5)要制备高密度的InAs/GaAs量子点，需要在生长技术上取得显著的进步。然而，在低温和/或高组成速率生长的InGaN/GaN量子阱中，形成了点状量子结构。它表现出发光增强和红移。(提交给国际半导体物理会议)(6)最终目标是寻找新的量子光电性质，如Stmaski-Krastanov生长模式下无序堆积的无序量子点(d-QD)的发光增强和红移。然而，这一研究项目取得的科技成果可以说是：d-量子点无序堆积层所期望的性质也被观察到了，无序量子线、自发有序半导体和由大的晶格失配引起的成分起伏的量子阱也观察到了这些性质。随着生长工艺的改进，量子光电性能的进一步发展是可以期待的

(1) The maximum thickness of the growth layer at which quantum dots begin to form naturally is derived theoretically for the heteroepitaxial growth of the semiconductor layer whose lattice constant differs from that of the semiconductor substrate. The theoretical results agree well with the experimental resutls of InAs/GaAs, InP/GaP, ans SiGe/Si. (published in Thin Solid Films)(2) The optimum thickness of GaAs layer for the InAs/GaAs quantum-dot stacked layer is experimentally determined. (published in Journal of Electronics Materials)(3) The disordered effects which causes the enhancement of luminescence intensity and the red shift of luminescence peak have been observed in the spontaneously ordered GaInP/GaAs. (published in Journal of Applied Physics) Although the luminecence enhancement and red-shift were observed in the ordered states in disordered matrix, the phenomena can be interpreted with the effects by thedisordered states in ordered matrix(4) The disordered quantum wire in w … More hich the wire width, thickness, and composition are disorderly fabricated exhibits the effects of luminescence enhancement and red-shift. (published in Applied physics Letters)(5) Remarkable progress in growth technology is required to fabricate a high density of InAs/GaAs quantum dot. Howerer, in the InGaN/GaN quantum well which is grown at the low temperature and/or with a high In composition rate, the dot-like quantum structure is formed. It exhibits the luminescence enhancement and the red-shift. (submitted to the International Conference on Physics of Semiconductors)(6) The final aim is to search new quantum optoelectronic properties such as the luminescence enhancement and the red-shift by disorderly stacked layer of disordered quantum dots (d-QDs) fabricated by the Stmaski-Krastanov growth mode. However, scientific and technological achievements by this research project can be stated as that the properties which were expected by disorderly stacked layer of d-QDs were observed also by the disordered quantum wires, the spontaneously ordered semiconductors, and the quantum well with compositional fluctuations caused by a large lattice-mismatching. Further development for the quantum optoelectronic properties can be expected by the improvement of the growth technology Less