钝化低温法生长多层InGaN量子点的结构和光学特性  

Structure and Luminescence Properties of Multi-sheet InGaN Quantum Dots Grown by Passivation-low-temperature Method

作　　者：陈振[1] 韩培德[2] 陆大成[1] 刘祥林[1] 王晓晖[1] 李昱峰[1] 袁海荣[1] 陆沅[1] 黎大兵[1] 王秀凤[3] 朱勤生[1] 王占国[1] 

机构地区：[1]中国科学院半导体研究所半导体材料科学重点实验室,北京100083 [2]中国科学院半导体研究所光电子器件研发中心,北京100083 [3]清华大学物理系,北京100084

出　　处：《发光学报》2003年第2期135-138,共4页Chinese Journal of Luminescence

基　　金：国家自然科学基金(60086001;69906002);国家重大基础研究项目(G20000683)资助项目

摘　　要：采用一种新方法生长多层InGaN/GaN量子点,研究所生长样品的结构和光学特性。该方法采用了低温生长和钝化工艺,所以称之为钝化低温法。第一层InGaN量子点的尺寸平均宽度40nm,高度15nm,量子点密度为6 3×1010/cm2。随着层数的增加,量子点的尺寸也逐渐增大。在样品的PL谱测试中,观察到在In(Ga)As材料系中普遍观察到的量子点发光的温度特性———超长红移现象。它们的光学特性表明:采用钝化低温法生长的纳米结构中存在零维量子限制效应。Multisheet InGaN quantum dots grown by a new method is reported, which is much different from the present quantum dots growth method. The dots are formed by de creasing the growth temperature and increasing the adatomhoppingenergy barri er through surface passivation. Thus the new method can be called as a passivation lowtemperature (PLT) method. Atomic force microscopy measurement reveal that the monolayer InGaN dots were small enough to expect zerodimensional quantum e ffect s. The size of monolayer QDs is typically 40nm wide and 15nm high. The QDs on u pp er layer can be grown bigger. The photoluminescence of (0001) InGaN multisheet QD s is measured. The PL spectra of (0001) InGaN/GaN multiple layers QDs show not o nly the QDsrelated peak but also an additional peak. This phenomenon is attrib u ted to the strong spontaneous and piezoelectric field along the (0001) orientati on. Temperature dependent PL studies reveal the strongly zerodimensional chara c ter of this QDs system. The experimental results show that, while for temperatur es lower than 50～60K and higher than 160K the peak energies follow the Varshni l aw, at the intermediate temperatures the energies decrease with increasing tempe ratures at a rate 6 times higher than that given by the Varshni law. The very si milar phenomena were also observed in InAs QDs system. The temperature dependent PL and the AFM studies make sure that the QDs is successfully fabricated by PLT method.

关 键 词：INGAN 外延生长 多层薄膜 铟镓氮三元化合物半导体 量子点 钝化低温法 零维量子限制效应 

分 类 号：O484.1[理学—固体物理] TN304.26[理学—物理]