Effects of post-deposition annealing and copper inclusion in superstrate Sb2Se3 based solar cells by thermal evaporation. (15th November 2019)

• Record Type: Journal Article
• Authors: Kumar, Vikash; Artegiani, Elisa; Kumar, Arun; Mariotto, Gino; Piccinelli, Fabio; Romeo, Alessandro
• Is Part Of: Solar energy. Volume 193(2019)
• Page Start: 452
• Page End: 457
• Publication Date: 2019-11-15
• Subjects: Thin films -- Sb2Se3 -- Copper -- Annealing; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2019.09.069
• Languages: English
• ISSNs: 0038-092X

Abstract

Highlights: 3.5% efficiency Sb2 Se3 device in superstrate configuration at low substrate temperature. Improvement of back contact by addition of ultra thin copper layer. Analysis of Sb2 Se3 structure after post-deposition annealing in vacuum. Abstract: Earth-abundancy, nontoxic constituent, along with excellent stability and optoelectronic properties make antimony selenide (Sb2 Se3 ) one of the potential candidate for low cost photovoltaics. In this work, antimony selenide (Sb2 Se3 ) thin films were prepared by low temperature thermal evaporation method and characterized. Solar cells were fabricated in the superstrate configuration of Glass/ITO/ZnO/CdS/Sb2 Se3 /Au. It was found that annealing in vacuum after Sb2 Se3 deposition played a significant role in the device performance. One-dimensional crystal structure of Sb2 Se3 with a preferred grain orientation was found to be beneficial for the higher performance of the solar cells with vacuum annealing at 300 °C. Furthermore, Cu addition after the deposition of Sb2 Se3 was introduced to improve the back contact and the device performance. In particular, Cu addition as a back contact leads to a significant increase in the Voc and the fill factor (FF). Moreover, aging of the finished cells during accelerated stability tests revealed a light soaking effect without degradation even in case of copper insertion. Our best solar cell showed a conversion efficiency of 3.5% without selenization.