1997 Fiscal Year Final Research Report Summary
Exciton Dynamics in CdZnTeSe Quaternary Alloys
| Project/Area Number |
08650021
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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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 | Hokkaido Institute of Technology |
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Principal Investigator |
IMAI Kazuaki Hokkado Institute of Technology, Department of Engineering, Prof., 工学部・応用電子工学科, 教授 (40001987)
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| Co-Investigator(Kenkyū-buntansha) |
SAWADA Takayuki Hokkado Institute of Technology, Department of Engineering, Prof., 工学部・応用電子工学科, 教授 (40113568)
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| Project Period (FY) |
1996 – 1997
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| Keywords | II-VI semiconductors / ZnSe / Excitions / Interface states |
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| Research Abstract |
1.In doped Cd_<1-X>Zn_XTe (x>0.7) have two types of acceptors from admittance spectroscopy and PL.One of them is so-called A-center. The other is located at E_V+0.27eV.
2.Huang-Rhys parameters S in ultra thin ZnSe-ZnTe superlattices are 3.5 and 7.5 for S1 and S2 emission bands, respectively. The configuration coordinates explain well the experiments.
3.The drift mobility of Cl doped Cd_<0.8>Zn_<0.2>Te was measured by TOF.The mobilty of electrons and holes were limited by so-called trap-controlled. The trap energies are E_C-0.03 and E_V+0.14eV,respectively.
4.The density of interface states, N_<SS>, of ZnSe/GaAs reduces by one order by suitable pretrearment of the substrate. N_<SS>, _<min> under the midgap of GaAs is 1x10^<11>cm^<-2>eV^<-1>.
5.MEE/ALE-ZnSe/GaAs with the highest quality can be grown by the mode of 1/4 ML growth per one supply of the element.
6.The barrier height at the re-grown homo-interface of MBE-ZnSe on GaAs is 0.7eV.
7.The time-resolved PL measurements were performed for S1 and S2 emission bands of superlattices consists of ZnSe and ultra thin ZnTe. Both bands involve shallow component, which can be further decomposed into each a first and slow band.
(1) The first bands are attributed to excitions localized in the long-range potential fluctuations.
(2) The decay of the slow bands is found to be well described by a stretched exponential function
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