The effect of Te-doping and heat treatment on the structural properties of CdTe absorber layer for CdS/CdTe solar cell

• Published in: Optical materials Vol. 134; p. 113061
• Main Authors: Kim, Hyon Chol, Jo, Hye Gang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2022
• Subjects: CdTe; Close spaced sublimation; Defect; Heat treatment; Solar cell; Stoichiometric; Te rich; Solar cell; Stoichiometric; Heat treatment; Te rich; Close spaced sublimation; Defect; CdTe
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2022.113061

Te rich CdTe thin films for absorber layer in CdS/CdTe solar cell were fabricated by the closed space sublimation method. Te enriched CdTe source materials with different Te rich contents were prepared before the deposition process of thin film. The properties of Te rich CdTe thin film were studied on the basis of the theoretical consideration of stoichiometric defect and self-doping. Here, we have considered the structural properties of CdTe with Te rich contents of 0, 1, 3, 5, 7, 10wt% by using scanning electron microscopy and X-ray diffraction. XRD measurements revealed that CdTe thin film had the largest lattice constant and the best crystallinity with less defects and stress at doping condition of 5%. Annealing in air represented more preferential orientation in (111) direction than the heat treatment in vacuum. We have analyzed the influence of Te doping and heat treatment on the structure and properties of CdTe:Te thin film to confirm more reasonable Te rich content and annealing atmosphere for CdTe thin film. Finally, we have determined Te rich content of the CdTe:Te thin film, 5%. •Te enriched CdTe source materials with different Te rich contents were prepared before the deposition process of thin film.•the theoretical consideration of stoichiometric and nonstoichiometric defect and self-doping was carried out.•XRD measurements revealed that CdTe thin film had the largest lattice constant and the best crystallinity with less defects and stress at doping condition of 5%.•Annealing in air represented more preferential orientation in (111) direction than the heat treatment in vacuum.•We have determined Te rich content of the CdTe:Te thin film, 5%.