AVS 58th Annual International Symposium and Exhibition
    Energy Frontiers Focus Topic Thursday Sessions
       Session EN-ThP

Paper EN-ThP10
Indium-Doped CdS Thin Film by He-Ne Laser Exposure for CIGS Solar Cells

Thursday, November 3, 2011, 6:00 pm, Room East Exhibit Hall

Session: Energy Frontiers Poster Session
Presenter: KukDo Myung, Chosun University, Republic of Korea
Authors: K. Myung, Chosun University, Republic of Korea
N. Kim, Chosun University, Republic of Korea
W. Lee, Chosun University, Republic of Korea
Correspondent: Click to Email
Cadmium sulfide (CdS) is a direct and wide band gap (2.42 eV at room temperature) II-VI semiconductor, which is a very desirable window layer for many photovoltaic solar cells including CIGS solar cell. CdS thin film has been paid to the considerable attention due to its band gap, high absorption coefficient, reasonable conversion efficiency, stability and low cost. It is generally known that the undoped CdS thin film has the high electrical resistivity. Some impurities were employed for doping CdS to produce less resistive films. Expecially, indium (In) showed the improvement of resistivity and optical transmittance when it was doped into the sputtering-deposited CdS thin film. In this study, the structural, optical, electrical, and morphological properties of indium-doped CdS thin films prepared by the effective method with He-Ne laser at room temperature. Indium was deposited on the 200 nm-thickness of CdS thin film by the sputtering method with 10 nm-thickness. He-Ne laser (632.8 nm) was exposured with a small energy by a change of exposure time. The remained indium layer was removed with the chemical solutions. The doping effects of indium on the CdS thin films were investigated by analyzing the structural, optical, electrical, and morphological properties of CdS thin films by using X-ray diffraction (XRD), Auger electron spectroscopy (AES), UV-Visible spectrophotometer, Hall effect measurement system, and atomic force microscope (AFM). AES depth profile was employed to examine the indium-doped CdS thin film with a change of He-Ne laser exposure time. The doping uniformity and amount of indium into the depth of CdS thin film was compared to the characteristics of CdS thin film. The optimization of indium-doping process was achieved to enhance the electrical and optical characteristics including resistivity and optical transmittance.