Yashraj Bhatnagar

Comprehensive experimental and numerical optimization of surface morphology of transparent conductive oxide films for tandem thin film photovoltaic cells

Typical thin-film photovoltaic cells incorporate a textured transparent conductive oxide to efficiently harvest solar energy. What should be the ideally desired morphology of this textured surface for best cell performance - is highly debated but remains an unsolved mystery. We present a comprehensive methodology to 1) accurately model, 2) extract macroscopically sufficient statistical finger-prints and 3) predict best desired values for these statistical finger-prints of such a randomly textured surface for the best performance of the cell.

Textured AZO on silicon oxy-nitride barrier films for enhanced light trapping in micromorph tandem junction solar cells

Aluminum doped Zinc Oxide (AZO) films have been reported as the transparent front contact layer in single and tandem junction thin film silicon solar cells. AZO films form highly transparent and conductive layers on glass surfaces with the possibility of further enhancement of solar cell performance by light trapping through wet-chemical texturing of the AZO surface. However, most reports have demonstrated such AZO films either on alumino-borosilicate glasses which are prohibitively expensive for low cost solar modules, or on commercial glass with barrier films deposited by other deposition methods.