Raytracing Modelling of Infrared Light Management Using Molybdenum Disulfide (MoS2) as a Back-Reflector Layer in a Silicon Heterojunction Solar Cell (SHJ)

The silicon heterojunction solar cell (SHJ) is considered the dominant state-of-the-art silicon solar cell technology due to its excellent passivation quality and high efficiency. However, SHJ’s light management performance is limited by its narrow optical absorption in long-wave near-infrared (NIR) due to the front, and back tin-doped indium oxide (ITO) layer’s free carrier absorption and reflection losses. Despite the light-trapping efficiency (LTE) schemes adopted by SHJ in terms of back surface texturing, the previous investigations highlighted the ITO layer as a reason for an essential long-wavelength light loss mechanism in SHJ solar cells. In this study, we propose the use of Molybdenum disulfide (MoS2) as a way of improving back-reflection in SHJ. The text presents simulations of the optical response in the backside of the SHJ applying the Monte-Carlo raytracing method with a web-based Sunsolve high-precision raytracing tool. The solar cells’ electrical parameters were also resolved using the standard electrical equivalent circuit model provided by Sunsolve. The proposed structure geometry slightly improved the SHJ cell optical current density by ~0.37% (rel.), and hence efficiency (η) by about 0.4% (rel.). The SHJ cell efficiency improved by 21.68% after applying thinner back ITO of about 30 nm overlayed on ~1 nm MoS2. The efficiency improvement following the application of MoS2 is tentatively attributed to the increased NIR absorption in the silicon bulk due to the light constructive interface with the backside components, namely silver (Ag) and ITO. Study outcomes showed that improved SHJ efficiency could be further optimized by addressing front cell components, mainly front ITO and MoS2 contact engineering.

Mohammed Islam Elsmani and Noshin Fatima and Ignacio Torres and Susana Fernández and Michael Paul A. Jallorina and Puvaneswaran Chelvanathan and Ahmad Rujhan Mohd Rais and Mohd Norizam Md Daud and Sharifah Nurain Syed Nasir and Suhaila Sepeai and Norasikin Ahmad Ludin and Mohd Asri Mat Teridi and Kamaruzzaman Sopian and Mohd Adib Ibrahim

Materials 2022, Vol. 15, Page 5024

computer simulations,dimensionality reduction,light trapping,photovoltaic cells,raytracing,thin films

2022

7

10.3390/MA15145024

1996-1944

14

5024

Multidisciplinary Digital Publishing Institute

15