Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Statistical Analysis of Surface Reconstruction Domains on InAs Wetting Layer Preceding Quantum Dot Formation | Nanoscale Res Lett 2010 5 1901-1904 DOI s11671-010-9754-3 SPECIAL ISSUE ARTICLE Statistical Analysis of Surface Reconstruction Domains on InAs Wetting Layer Preceding Quantum Dot Formation Tomoya Konishi Shiro Tsukamoto Received 25 June 2010 Accepted 10 August 2010 Published online 24 August 2010 The Author s 2010. This article is published with open access at Abstract Surface of an InAs wetting layer on GaAs 001 preceding InAs quantum dot QD formation was observed at 300 C with in situ scanning tunneling microscopy STM . Domains of 1 X 3 2 X 3 and 2 X 4 surface reconstructions were located in the STM image. The density of each surface reconstruction domain was comparable to that of subsequently nucleated QD precursors. The distribution of the domains was statistically investigated in terms of spatial point patterns. It was found that the domains were distributed in an ordered pattern rather than a random pattern. It implied the possibility that QD nucleation sites are related to the surface reconstruction domains. Keywords InAs Wetting layer Quantum dot Surface reconstruction Spatial point pattern Quantum dots QDs are potentially used for high-efficiency laser devices 1 . It is crucial to control QD formation to arrange QDs with high uniformity and high density. Little is known however of the growth mechanism of QDs in particular the surface reconstruction of a wetting layer WL and QD nucleation sites in Stranski-Krastanow S-K mode. Because the surface reconstruction changes microscopically and dynamically in the course of WL growth an in situ scanning tunneling microscopy STM technique such as STMBE 2 is essential. Atomic-scale in situ observation of an InAs WL on a GaAs 001 T. Konishi S. Tsukamoto Anan National College of Technology Anan Tokushima 774-0017 Japan e-mail konishi@ substrate has revealed that the surface reconstruction of the InAs WL changes from c 4 X 4 to the mixture of 1 X 3 2 X 3 and 2 X 4 prior to QD .
