扫描隧道显微镜对InAs/GaAs自组织生长量子点的准原位研究

In situ , Scanning Tunneling Microscope Studies of InAs/GaAs Self Organized Quantum Dots

本文报道了用ＭＢＥ－ＳＰＭ联合系统对ＩｎＡｓ／ＧａＡｓ量子点进行准原位研究的初步结果．ＳＴＭ图像表明，在对ｎ＋－ＧａＡｓ衬底进行脱氧处理后，通过生长ＧａＡｓ缓冲层能有效的改善表面质量．在缓冲层上继续生长２单原子层ＩｎＡｓ后形成了量子点．ＳＰＭ与透射电子显微镜给出的量子点形貌的异同在文中也给出了合理的解释，该研究工作的进一步深入将对自组织生长量子点的生长机理的理解和样品质量的提高有重要意义．

Abstract We present our preliminary results of in situ scanning tunneling microscope investigations on InAs/GaAs self organized quantum dots with our MBE SPM combined system. STM images show that, after the deoxidization process on n + GaAs substrate, growing GaAs buffer can effectively improve the surface quality. After growing 2 monolayers InAs on the buffer, quantum dots will be formed. We also give reasonable explanations about the differences between the results given by the STM and TEM measurements. Further research in this field will help us to understand the growth mechanism of the self organized quantum dots and to make good quality sample.