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: Surface Morphology Evolution of GaAs by Low Energy Ion Sputtering | Nanoscale Res Lett 2007 2 504-508 DOI S11671-007-9090-4 NANO EXPRESS Surface Morphology Evolution of GaAs by Low Energy Ion Sputtering Y. Wang S. F. Yoon C. Y. Ngo J. Ahn Received 18 May 2007 Accepted 17 August 2007 Published online 12 September 2007 to the authors 2007 Abstract Low energy Ar ion sputtering typically below 1 200 eV of GaAs at normal beam incident angle is investigated. Surface morphology development with respect to varying energy is analyzed and discussed. Dot-like patterns in the nanometer scale are obtained above 600 eV. As the energy approaches upper eV range regular dots have evolved. The energy dependent dot evolution is evaluated based on solutions of the isotropic Kuramoto-Sivashinsky equation. The results are in agreement with the theoretical model which describes a power law dependency of the characteristic wavelength on ion energy in the ion-induced diffusion regime. Keywords Low energy Ion sputtering Surface morphology GaAs quantum dot Introduction The sputtering phenomenon which is caused by the interaction of incident particles with target surface atoms was first observed by Grove in a dc gas discharge tube in 1852 1 . This once regarded as undesired side effect has now been widely developed and used at large for surface cleaning and etching thin film deposition surface and surface layer analysis and has long been a leading candidate for surface patterning. While ripple formation on sputtering-eroded surfaces has been observed in the 1970s 2 a self-organization process using low energy ion Y. Wang H S. F. Yoon C. Y. Ngo J. Ahn School of Electrical and Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Singapore e-mail wangyang@ sputtering of semiconductor surface at normal beam incidence angle has been found recently to be capable of producing highly uniform nanoscale islands 3 . This sputtering generated surface modification is believed to be a potential alternative to .
