한국진공학회:학술대회논문집 (Proceedings of the Korean Vacuum Society Conference)
- 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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- Pages.293-294
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- 2011
Optical Characteristics of Near-monolayer InAs Quantum Dots
- Kim, Yeong-Ho (Department of Nanoelectronics, University of Science and Technology & Nano Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
- Kim, Seong-Jun (Department of Nanoelectronics, University of Science and Technology & Nano Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
- No, Sam-Gyu (Department of Nanoelectronics, University of Science and Technology & Nano Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
- Park, Dong-U (Division of Advanced Materials Engineering, Chonbuk National University) ;
- Kim, Jin-Su (Division of Advanced Materials Engineering, Chonbuk National University) ;
- Im, In-Sik (Department of Physics, Yeungnam University) ;
- Kim, Jong-Su (Department of Physics, Yeungnam University)
- 발행 : 2011.08.17
초록
It is known that semiconductor quantum-dot (QD) heterostructures have superior zero-dimensional quantum confinement, and they have been successfully applied to semiconductor laser diodes (QDLDs) for optical communication and infrared photodetectors (QDIPs) for thermal images [1]. The self-assembled QDs are normally formed at Stranski-Krastanov (S-K) growth mode utilizing the accumulated strain due to lattice-mismatch existing at heterointerfaces between QDs and cap layers. In order to increase the areal density and the number of stacks of QDs, recently, sub-monolayer (SML)-thick QDs (SQDs) with reduced strain were tried by equivalent thicknesses thinner than a wetting layer (WL) existing in conventional QDs (CQDs) by S-K mode. Despite that it is very different from CQDs with a well-defined WL, the SQD structure has been successfully applied to QDIP[2]. In this study, optical characteristics are investigated by using photoluminescence (PL) spectra taken from self-assembled InAs/GaAs QDs whose coverage are changing from submonolayer to a few monolayers. The QD structures were grown by using molecular beam epitaxy (MBE) on semi-insulating GaAs (100) substrates, and formed at a substrate temperature of 480