Versatile and Quantitative Spectrometer of Nonradiative recombination centers by Using Two-Wavelength Excitation method
| Project/Area Number |
14350002
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Applied materials science/Crystal engineering
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| Research Institution | Saitama University |
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Principal Investigator |
KAMATA Norihiko Saitama University, Faculty of Engineering, Prof., 工学部, 教授 (50211173)
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| Co-Investigator(Kenkyū-buntansha) |
ARAKAWA Yasuhiko University of Tokyo, RCAST, Prof., 先端科学技術研究センター, 教授 (30134638)
SOMEYA Takao University of Tokyo, Grad.Engineering, Assoc.Prof, 工学系研究科, 助教授 (90292755)
HONDA Zentaroh Saitama University, Faculty of Engineering, Research Assoc., 工学部, 助手 (30332563)
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| Project Period (FY) |
2002 – 2004
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| Project Status |
Completed (Fiscal Year 2004)
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| Budget Amount *help |
¥6,800,000 (Direct Cost: ¥6,800,000)
Fiscal Year 2004: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2003: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 2002: ¥3,800,000 (Direct Cost: ¥3,800,000)
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| Keywords | photoluminescence / nonradiative recombination center / GaN / UV-and blue-light emitting materials / quantum well / quantum dot / 量子井戸構造 |
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| Research Abstract |
We exemplified the following research results during the project :
(1)By combining a tunable below-gap excitation source (Optical Parametric Oscillator) and a sensitive CCD camera etc., we realized more versatile system of two-wavelength excited photoluminescence(TWEPL) for wider materials.
(2)Inserting buffer layers with sufficient thickness, increasing quantum-well periods and utilizing modulation-doping were found to be effective for improving light emission efficiency through the characterization of GaN/AlGaN quantum wells grown by plasma-assisted MBE in Hannover University (Germany) and by our MOCVD technique.
(3)We observed directly the formation of a trap-level due to an UV light irradiation during the measurement. The BGE effect after the trap formation was explained well by our two-levels model.
(4)First detection of nonradiative centers in an InAs quantum dot has been done. Its temperature dependence is important for analyzing carrier dynamics in the quantum dot. In addition, a new trap level in a Y_2O_2S:Eu phosphor was resolved clearly by combining TWEPL with thermo-luminescence technique.
Thus our TWEPL spectrometer became a versatile way to characterize belowgap states in wider range of light emitting materials.
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Report
(4 results)
Research Products
(22 results)
