Title :
High efficient thin film CdTe solar cells
Author :
Ruilong Yang ; Zhizhong Bai ; Dezhao Wang ; DeLiang Wang
Author_Institution :
Hefei Nat. Lab. for Phys. Sci. at the Microscale, Univ. of Sci. & Technol. of China, Hefei, China
Abstract :
CdTe thin film solar cell with an absorber layer as thin as 0.5 μm was fabricated. An efficiency of 7.9 % was obtained for a 1-μm-thick CdTe solar cell. The experimental results presented in this study demonstrated that 1-μm-thick absorber layer is thick enough to fabricate CdTe solar cell with a decent efficiency. Formation of mono-grain CdS layer with grain size in submicron was fabricated. Heat treatment of a CdS precursor layer coated with a CdCl2 layer and under a high CdCl2 vapor pressure reduced oxide formation at the grain surface and promoted grain coalescence. High crystalline quality mono-grain CdS layer ensured homogenous intermixing of CdS and CdTe at the CdS/CdTe interface. A saturated junction leakage current in the order of 10-10 A/cm2 and a short-circuit current as high as 25.1 cm/cm2 were obtained for a mono-grain-CdS/CdTe solar cell. The corresponding solar cell efficiency is 14.6%.
Keywords :
II-VI semiconductors; cadmium compounds; heat treatment; leakage currents; semiconductor thin films; short-circuit currents; solar cells; CdCl2; CdS; CdTe; grain coalescence; grain size; grain surface; heat treatment; homogenous intermixing; precursor layer; saturated junction leakage current; short-circuit current; size 0.5 mum; size 1 mum; solar cell efficiency; thin film solar cells; Absorption; Coatings; Films; Junctions; Morphology; Photovoltaic cells; Surface treatment; CdS; CdTe; efficiency; solar cell;
Conference_Titel :
Electron Devices (CDE), 2013 Spanish Conference on
Conference_Location :
Valladolid
Print_ISBN :
978-1-4673-4666-5
Electronic_ISBN :
978-1-4673-4667-2
DOI :
10.1109/CDE.2013.6481412
