Effect of laser fluence on the ITO/Mo-Ag/ITO multilayer thin film for a-Si (n)/c-Si(p)/a-Si(p)/Al heterojunction solar cells

In this study, innovative ITO/Mo-Ag/ITO (IMAI) multilayered thin films were sputtered and annealed via Nd: YAG pulsed laser at different fluences to enhance their physical properties. The structural investigation shows a cubic structure, which was improved by laser annealing. Moreover, it shows that crystallite size enlarged with the increase in laser fluence from 22 to 37 nm. The average optical transmittance improved from 82 to 92 % in the visible range. The AFM and FESEM show a uniform morphology, with granular structure significantly improved by the laser fluence. The surface roughness was decreased from 2.5 to 0.5 nm, and the average grain size was enlarged from 41.2 to 72.3 nm. Electrical resistivity shows a remarkable decrease from 7.18 x 10-4 to 2.01 x 10-5 Omega/cm, followed by an enhancement in the ohmic contact of IMAI/p-Si. The optimized IMAI structure was utilized to simulate an a-Si(n)/c-Si(p)/a-Si(p)/Al heterojunction solar cell as a transparent conducting window (TCW) using AFORS-HET software. Compared to ITO, the IMAI structure shows remarkable conversion performance, which achieved 22.14 %. Consequently, laser annealing improves the thin film properties for solar cell applications.