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: Interwell coupling effect in Si/SiGe quantum wells grown by ultra high vacuum chemical vapor deposition | Nanoscale Res Lett 2007 2 149-154 DOI s11671-007-9046-8 NANO EXPRESS Interwell coupling effect in Si SiGe quantum wells grown by ultra high vacuum chemical vapor deposition Rui Wang Soon Fatt Yoon Fen Lu Wei Jun Fan Chong Yang Liu Ter-Hoe Loh Hoai Son Nguyen Balasubramanian Narayanan Published online 27 February 2007 to the authors 2007 Abstract Si coupled quantum well CQW structures with different barrier thickness of 40 4 and 2 nm were grown on Si substrates using an ultra high vacuum chemical vapor deposition UHV-CVD system. The samples were characterized using high resolution x-ray diffraction HRXRD crosssectional transmission electron microscopy XTEM and photoluminescence PL spectroscopy. Blue shift in PL peak energy due to interwell coupling was observed in the CQWs following increase in the Si barrier thickness. The Si SiGe heterostructure growth process and theoretical band structure model was validated by comparing the energy of the no-phonon peak calculated by the 6 2-band k-p method with experimental PL data. Close agreement between theoretical calculations and experimental data was obtained. Keywords Si SiGe Coupled quantum well uHv-cvd Introduction Silicon is notably the most widely used semiconductor in the microelectronics industry. As such the ability to R. Wang S. F. Yoon El F. Lu W. J. Fan C. Y. Liu School of Electrical and Electronic Engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Singapore e-mail esfyoon@ . Loh H. S. Nguyen B. Narayanan Institute of Microelectronics 11 Science Park Road Singapore Science Park II Singapore 117685 Singapore realize light emitters based on silicon is a highly desirable goal that could lead to integrating optical and microelectronic functions on the same silicon-based platform. However the indirect band characteristic of silicon prohibits the efficient radiative recombination of electrons and holes to result in coherent optical emission. Currently there
