We report the properties of infrared photodetectors based on two kinds of quantum dots(QDs): i) 2.0 ML InAs QDs by the Stranski-Krastanov growth mode(SK QDs) and ii) sub-monolayer QDs by 4 × [0.3 ML/1 nm In0.15Ga0.85As] deposition(SML QDs). The QD infrared photodetector(QDIP) structure of n+-n−(QDs)-n+ is epitaxially grown on GaAs (100) wafers using molecular-beam epitaxy. Both the bottom and top contact GaAs layers are Si doped at 2 × 1018/cm3. The QD layers are grown with Si doping of 2 × 1017/cm3 and capped by an In0.15Ga0.85As layer at 495 oC. The photoluminescence peak(1.24 eV) of the SML QDIP is blue-shifted with respect to that (1.04 eV) of SK QDIPs, suggesting that the electron ground state of SML QDIP is higher than that of the SK QDIP. As a result, the photoresponse regime(~9-14 μm) of the SML QDIP is longer than that (~6-12 μm) of the SK QDIP. The dark current of the SML QDIP is two orders of magnitude smaller value than that of the SK QDIP because of the inserted Al0.08Ga0.92As layer.

Abstract
 1. 서 론
 2. 실험 방법
 3. 결과 및 고찰
 4. 결 론
 References

• 서동범(충남대학교 공과대학 신소재공학과) | Dong-Bum Seo (Department of Materials Science & Engineering, Chungnam National University)
• 황제환(한국표준과학연구원 융합물성측정센터) | Je-hwan Hwang (Division of Convergence Technology, Korea Research Institute of Standard Science)
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• 노삼규(한국표준과학연구원 융합물성측정센터) | Sam Kyu Noh (Division of Convergence Technology, Korea Research Institute of Standard Science)
• 김준오(한국표준과학연구원 융합물성측정센터) | Jun Oh Kim (Division of Convergence Technology, Korea Research Institute of Standard Science)
• 이상준(한국표준과학연구원 융합물성측정센터) | Sang Jun Lee (Division of Convergence Technology, Korea Research Institute of Standard Science)
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