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Solar Cell Fabrication and Characterisation

  • A. A. Ojo
  • W. M. Cranton
  • I. M. Dharmadasa
Chapter

Abstract

This chapter provides an insight into next-generation graded bandgap photovoltaic device fabrication. All-electrodeposited devices were fabricated using n-p, n-n-p, n-n + large Schottky barrier (SB) and n-n-n + SB architecture using ZnS, CdS and CdTe thin layers. The fabricated devices were evaluated using both current-voltage (I-V) and capacitance-voltage (C-V) techniques. The inclusion of Ga into the regular CdCl2 post-growth treatment and the effect of pH were also explored with the improved result as compared to the regular CdCl2 PGT. Based on all experimental findings as explored within the limit of this work, the most promising of the configurations examined are the glass/FTO/n-CdS/n-CdTe/p-CdTe/Au with thicknesses of 120 nm (n-CdS), 1200 nm (n-CdTe), 30 nm (p-CdTe) and 100 nm (Au). The highest conversion efficiencies observed for two separate batches were 15.3 and 18.4%. The devices with the 18.4% efficiency showed some instability and therefore require further investigation. The glass/FTO/n-ZnS/n-CdS/n-CdTe/Au configuration with thicknesses of 50 nm (n-ZnS), 65 nm (n-CdS), 1200 nm (n-CdTe) and 100 nm (Au) also shows promising results with the highest efficiency achieved being 14.1% owing to bandgap grading strengths.

Keywords

ZnS CdS CdTe All-electroplating of semiconductors Graded bandgap solar cells Shockley-Queisser limit 

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • A. A. Ojo
    • 1
  • W. M. Cranton
    • 1
  • I. M. Dharmadasa
    • 1
  1. 1.Sheffield Hallam UniversitySheffieldUK

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