Chemically deposited CdS by an ammonia-free process for solar cells window layers

• Published in: Solar energy Vol. 84; no. 2; pp. 208 - 214
• Main Authors: Ochoa-Landín, R., Sastre-Hernández, J., Vigil-Galan, O., Ramírez-Bon, R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2010; Elsevier; Pergamon Press Inc
• Subjects: Ammonia; Ammonia-free; Applied sciences; CADMIUM SULFIDES; CADMIUM TELLURIDE SOLAR CELLS; CHELATING AGENTS; Chemical synthesis; CHEMICAL VAPOR DEPOSITION; CITRATES; CONVERSION; Diffraction; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; Energy; Exact sciences and technology; FLUORINE; INDIUM OXIDES; LAYERS; Microscopy; Natural energy; Photovoltaic cells; Photovoltaic conversion; QUANTUM EFFICIENCY; SODIUM COMPOUNDS; Solar cells; Solar cells. Photoelectrochemical cells; SOLAR ENERGY; SPECTRAL RESPONSE; Spectrum analysis; SUBSTRATES; TIN OXIDES; TRANSMISSION; Window layer; WINDOWS; Solar cells; Window layer; Chemical synthesis; Ammonia-free; Absorbent; Cadmium telluride solar cells; Atomic force microscopy; Spectral response; Cadmium sulfide solar cells; Chemical bath deposition; Fluorine; X ray spectrometry; Windows; Quantum yield; Solar cell; Ammonia; Sodium; Optical transmission; Tin oxide; ITO layers; Characteristics measurement; X ray diffractometry; Performance
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2009.11.001

Chemically deposited CdS window layers were studied on two different transparent conductive substrates, namely indium tin oxide (ITO) and fluorine doped tin oxide (FTO), to determine the influence of their properties on CdS/CdTe solar cells performance. Three types of CdS films obtained from different chemical bath deposition (CBD) processes were studied. The three CBD processes employed sodium citrate as the complexing agent in partial or full substitution of ammonia. The CdS films were studied by X-ray diffraction, optical transmission spectroscopy and atomic force microscopy. CdS/CdTe devices were completed by depositing 3 μm thick CdTe absorbent layers by means of the close-spaced vapor transport technique (CSVT). Evaporated Cu–Au was used as the back contact in all the solar cells. Dark and under illumination J–V characteristic and quantum efficiency measurements were done on the CdS/CdTe devices to determine their conversion efficiency and spectral response. The efficiency of the cells depended on the window layer and on the transparent contact with values between 5.7% and 8.7%.