超高真空化学气相淀积自组织生长锗量子点

采用超高真空化学气相淀积系统制备了小尺寸、高密度、纵向自对准的Ge量子点．通过TEM和AFM对埋层和上层量子点的形貌和尺寸分布进行了研究，对生长的温度和时间进行了优化．采用硼预淀积的方法得到了尺寸分布小于3％的均匀的圆顶形Ge量子点．采用低温光荧光测量了多层量子点的光学特性．在10K的PL谱可以观察到明显的蓝移现象，表明量子点中较强的量子限制效应．量子点非声子峰的半高宽约为46meV，表明采用UHV／CVD工艺生长的多层量子点具有较窄的尺寸分布．

Self-Organized Growth of Ge Quantum Dots by UHV/CVD

Small size, large density and vertical ordering Ge quantum dots (QDs) were grown by ultra-high vacuum chemical vapor deposition(UHV/CVD) system. The morphology and size distribution of embedded and upper Ge dots were studied by TEM and AFM to optimize growth temperature and duration. Uniform dome-shaped Ge QDs were obtained after boron pre-deposition with narrow size distribution less than 3%. The optical characteristics of stacked Ge QDs were studied by low temperature photoluminescence(PL). From PL Spectrum under 10 K obvious blue shift was observed induced by strong quantum confinement effect. FWHM of Ge dots NP peak of about 46 meV indicates the narrow size distribution of stacked Ge dots grown by UHV/CVD.