The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on Ion Exchange Method for Effective Ag Doping of Sputtering-Deposited CdTe Thin Film

스퍼터링 증착한 CdTe 박막의 효과적인 Ag 도핑을 위한 이온 교환법 연구

  • 김철준 (조선대 공대 전기공학과) ;
  • 박주선 (조선대 공대 전기공학과) ;
  • 이우선 (조선대 공대 전기공학과)
  • Received : 2011.04.11
  • Accepted : 2011.05.23
  • Published : 2011.06.01

Abstract

CdTe thin-film solar cell technology is well known that it can theoretically improve its conversion efficiency and manufacturing costs compared to the conventional silicon solar cell technology, due to its optical band gap energy (about 1.45eV) for solar energy absorption, high light absorption capability and low cost requirements for producing solar cells. Although the prior studies obtained the high light absorption, CdTe thin film solar cell has not been come up to the sufficient efficiency yet. So, doping method was selected for the improvement of the electrical characteristics in CdTe solar cells. Some elements including Cu, Ag, Cd and Te were generally used for the p-dopant as substitutional acceptors in CdTe thin film. In this study, the sputtering-deposited CdTe thin film was immersed in $AgNO_3$ solution for ion exchange method to dope Ag ions. The effects of immersion temperature and Ag-concentration were investigated on the optical properties and electrical characteristics of CdTe thin film by using Auger electron spectroscopy depth-profile, UV-visible spectrophotometer, and a Hall effect measurement system. The best optical and electrical characteristics were sucessfully obtained by Ag doping at high temperature and concentration. The larger and more uniform diffusion of Ag ions made increase of the Ag ion density in CdTe thin film to decrease the series resistance as well as mede the faster diffusion of light by the metal ions to enhance the light absorption.

Keywords

File

Download PDF

Acknowledgement

Supported by : 한국연구재단

References

  1. 조은철, 조영현, 김동섭, 이수홍, 지일환, "실리콘 태양전지의 개발현황", 전기전자재료, Vol. 8, No. 3, pp. 362-371, 1995.
  2. 안병태, "CdTe 박막 태양전지 기술동향", 한국태양에너지학회지 Vol. 4, No. 3, pp. 33-39, 2005.
  3. 윤경훈, "박막 태양전지 기술개발 현황", 한국전기화학회, 전지기술심포지움 학술대회지, pp. 189-210, 2001.
  4. 이재형, 최성현, 이동진, 이종인, 양동건, 양계준, 이준신, "스퍼터 압력에 따른 태양전지용 CdTe 박막의 구조적, 광학적 특성", 한국전기전자재료학회, 추계학술대회논문집, pp. 101-102, 2005.
  5. 윤재호, 안병태, 김동환, "CdTe 박막 태양전지의 기술 동향", 한국세라믹학회 세라미스트, Vol. 8, No. 5, pp. 47-52, 2005.
  6. Youn-Ok Choi, Nam-hoon Kim, Ju-Sun Park, Woo-Sun Lee, "Influences of thickness-uniformity and optical properties of sputtered CdTe thin film for large-area II-VI semiconductor heterostructured solar cells", Materials Science and Engineering B, Vol. 171, pp, 73-78, 2010. https://doi.org/10.1016/j.mseb.2010.03.072
  7. Steven S, Hegedus, Brian E,McCandless, "CdTe contacts for CdTe/CdS sollar cells: effect of Cu thickness, surface preparation and recontacting on device performance and stability", Aolar Energy Materials & Solar Cells , Vol. 88, pp. 75-95, 2005. https://doi.org/10.1016/j.solmat.2004.10.010
  8. N.-H. Kim, Y.O. Choi and W.-S. Lee, "Enhancement of optical properties for CdTe absorber through improving thickness uniformity by CMP process", Electronics Letters, Vol. 46, No. 14, pp. 1019-1021, 2010. https://doi.org/10.1049/el.2010.1135
  9. Nazar Abbas Shah, Abid AliAsghari, Maqsood, "Characterization of CdTe thin films fabricated by close spaced sublimation technique and a study of Cu doping by ion exchange process", Journal of Non-Crystalline Solids, Vol. 355, pp, 1474-1478, 2009. https://doi.org/10.1016/j.jnoncrysol.2009.05.016
  10. N. Abbas Shah,A. Ali, A.K.S. Aqili, A. Maqsood, "Physical properties of Ag-doped cadmium telluride thin films fabricated by closed-space sublimation technique", Journal of Crystal Growth, Vol. 290, pp. 452-458, 2006. https://doi.org/10.1016/j.jcrysgro.2006.01.051
  11. 최진영, 이임근, 정종진, 박성준, 이동윤, 김희제, "연료 감응형 태양전지의 대면적화에 따른 셀 특성 연구", 한국신.재생에너지학회 춘계학술대회논문집, pp, 189-191, 2005.
  12. 정해원, 이천, 신재혁, 신성호, 박광자, "스퍼터링에 의한 CdTe박막 제조 조건이 CdTe/CdS 태양전지의 특성에 미치는 영향", 전기전자재료학회논문지, Vol. 10, No. 9, pp. 930-937, 1997.
  13. Dr. D. A, MacINNES, "THE INTERIONIC ATTRACTION THEORY OF ELECTROLYTES", SCIENCE, Vol. 86, No. 2219, pp. 23-29, 1937. https://doi.org/10.1126/science.86.2219.23
  14. Nam-Hoon Kim, Yong-Jin Seo, Woo-Sun Lee, "Effects of Silica Slurry Temperature on Chemical Mechanical Polishing for Tetraethy1 Orthosilicate (TEOS) Film", Japanese Journal of Applied Physics, Vol. 44, No. 40, pp. L1256-L1258, 2005. https://doi.org/10.1143/JJAP.44.L1256
  15. 여종빈, 윤상돈, 이현용, "홀로-리소그라피를 이용한 칼코게나이드 박막으로의 Ag 포토도핑의 기판 의존성", 전기전자재료학회 하계학술대회논문집, pp. 189-190, 2007.
  16. 정해원, 이천, 신재혁, 신성호, 박광자, "스퍼터링에 의한 CdTe 박막 제조 조건이 CdTe/CdS 태양전지의 특성에 미치는 영향", 전기전자재료학회지, Vol. 10, NO. 9, pp. 930-937, 1997.
  17. S. Calnan, A.N. Tiwari, "High mobility transparent conducting oxides for thin film solar cells", Thin Solid Films, Vol. 518, pp. 1839-1849, 2010. https://doi.org/10.1016/j.tsf.2009.09.044
  18. A. Ali, N. Abbas shah, A. Maqsood, "Characterization of cadmium telluride thin films fabricated by two-source evaporation technique and Ag doping by ion exchange process", Solid-State Electronics, Vol.52, pp. 205-210, 2008. https://doi.org/10.1016/j.sse.2007.08.016
  19. 윤보경, 박철민, "블록공중합체 광자결정", 고분자과학과 기술, Vol. 15, No. 3, pp. 317-326, 2004.
  20. 임정욱, 윤선진, 이승윤, "박막 실리콘 태양전지의 광이용률 개선 기술", 정보통신산업진흥원 주간기술동향, pp. 1-13, 2011.