MBE生长InGaAs/GaAs(001)多层矩阵式量子点

Fabrication of InGaAs quantum dot 2D-arrays on GaAs(001) by MBE

用分子束外延(MBE)设备以Stranski-Krastanov(S-K)生长模式,通过间歇式源中断方式外延生长了多个周期垂直堆垛的InGaAs量子点,首次获得大小及密度可调的In0.43Ga0.57As/GaAs(001)矩阵式量子点DWELL结构。样品外延结构大致为500nm的GaAs、多个周期循环堆垛InGaAs量子点和60ML的GaAs隔离层等。生长过程中用反射式高能电子衍射仪(RHEED)实时监控,样品经退火后使用扫描隧道显微镜(STM)进行表面形貌的表征。

Multi-period vertically stacked InGaAs quantum dots were grown by molecular beam epitaxy in Stranski-Krastanov mode with interruption of source, the multilayered 2D-arrays In0.43 Ga0. 57 As/GaAs（001） dots-in- a-well were obtained with tunable dimension and density. The epitaxy structure of sample is composed of 500nm GaAs buffer layer, multi-period stacked InGaAs quantum dots and 60 monolayer GaAs. The growth process was monitored real time with reflection high energy electron diffraction, the surface morphology of sample was scanned with scanning tunneling microscope after anneal.