Correlation of Interfacial Transportation Properties of CdS/CdTe Heterojunction and Performance of CdTe Polycrystalline Thin-Film Solar Cells

Autor: Guanggen Zeng, Jingquan Zhang, Wenwu Wang, Lianghuan Feng
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: International Journal of Photoenergy, Vol 2015 (2015)
Druh dokumentu: article
ISSN: 1110-662X
1687-529X
DOI: 10.1155/2015/519386
Popis: The light and dark output performances of CdS/CdTe solar cells made by close-spaced sublimation (CSS) were investigated to elucidate the transportation properties of carriers at CdS/CdTe heterojunction interface. It has been found that the interfacial transportation properties were relatively sensitive to variations of the characteristics of heterojunction due to the series resistance and shunting effects. For the high quality cell with 12.1% efficiency, narrow depletion region of ~1.1 microns and large electric field intensity of ~1.3 V/μm allow the sufficient energy-band bending close to CdS layer at CdS/CdTe heterojunction, which changes the carrier transportation mechanism from emission to diffusion and leads to the optimal rectifying characteristics with small dark saturation current density ~6.4 × 10−10 A/cm2. As a result, the schematic diagram of heterojunction band structure corresponding to various performances of solar cells has also been presented.
Databáze: Directory of Open Access Journals