Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Molecular Linker Enhanced Assembly of CdSe/ZnS Core-Shell Quantum Dots

분자 끈을 활용한 CdSe/ZnS 양자 점의 향상된 배열

  • Cho, Geun Tae (Department of Chemistry-BK21and Sungkyunkwan Advanced Institute of Nanotechnology, Institute of Basic Sciences, Sungkyunkwan University) ;
  • Lee, Jong Hyeon (Department of Chemistry-BK21and Sungkyunkwan Advanced Institute of Nanotechnology, Institute of Basic Sciences, Sungkyunkwan University) ;
  • Nam, Hye Jin (Department of Chemistry-BK21and Sungkyunkwan Advanced Institute of Nanotechnology, Institute of Basic Sciences, Sungkyunkwan University) ;
  • Jung, Duk Young (Department of Chemistry-BK21and Sungkyunkwan Advanced Institute of Nanotechnology, Institute of Basic Sciences, Sungkyunkwan University)
  • 조근태 (성균관대학교 화학과, 성균 나노과학원, 기초과학연구소) ;
  • 이종현 (성균관대학교 화학과, 성균 나노과학원, 기초과학연구소) ;
  • 남혜진 (성균관대학교 화학과, 성균 나노과학원, 기초과학연구소) ;
  • 정덕영 (성균관대학교 화학과, 성균 나노과학원, 기초과학연구소)
  • Received : 2008.06.09
  • Accepted : 2008.12.01
  • Published : 2008.12.31
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Abstract

QDs-LEDs(quantum dot light emitting device) should contain well-organized arrays of QDs on an electron transport layer. Thin films of CdSe/ZnS core-shell QDs were successfully fabricated on $TiO_2$ substrates by using PDMS stamp and micro contact printing method. 2-Carboxyethylphosphonic acid(CAPO) and 1,6-hexanedithiol(HDT) were employed as molecular linkers in assembling CdSe/ZnS core-shell QDs with high-density and uniform array. The CAPO increased the binding strength between the QDs and the substrates, and the HDT induced the strong inter-particle attractions of assembled QDs. The assembling properties of QDs thin films were characterized by SEM, AFM, optical microscope and photoluminescence spectroscope(PL).

양자 점을 이용한 QD-LED(Quantum Dot - Light Emitting Device)의 소자 제작을 하기 위해서는 양자 점의 균일한 배열이 중요하다. 핵-껍질(core-shell) 구조의 CdSe/ZnS 양자 점을 기판에 고 밀도, 고 균일도로 배열하기 위하여 두 종류의 분자 끈(molecular linker)을 사용하였고, 공정의 단순화와 비용 절감을 위하여 고분자 도장인 PDMS(polydimethylsiloxane)를 이용한 미세접촉인쇄방법으로 양자 점들을 배열하였다. $TiO_2/ITO$ 기판에 양자 점을 고정시켜주는 역할을 하는 분자 끈으로는 2-carboxyethylphosphonic acid(CAPO)를 사용하였고, 양자 점 사이의 인력을 향상시켜주는 분자 끈으로는 1,6-hexanedithiol(HDT)을 사용하였다. 양자 점들의 배열 특성을 주사전자현미경(SEM, scanning electron microscope)과 원자 힘 현미경(AFM, atomic force microscope)으로 분석하였고, 광 발광분광기(PL, photoluminescence spectroscope)로 발광특성을 측정하였다.

Keywords

Acknowledgement

Supported by : 성균관대학교

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