Investigating Reasons for Poor Performance of CdS/p-SnS Solar Cells Yashika Gupta1; Arun Palakkandy2; 1UNIVERSITY OF DELHI, Delhi, India; 2S.G.T.B. KHALSA COLLEGE, UNIVERSITY OF DELHI, Delhi, India; PAPER: 190/AdvancedMaterials/Regular (Oral) SCHEDULED: 14:00/Wed./Grego (50/3rd) ABSTRACT: Search for an efficient and low cost alternative to Silicon-wafer solar cells has led to the popularity of thin film photovoltaics. Tin Sulphide (SnS), being an earth abundant, cheap, and less toxic semiconducting material [1,2] with a high absorption coefficient (> 104 cm-1) in visible range [3], stands out as a potential candidate. Theoretical simulations by Loferski et al. [4] predicted 24% efficiency for SnS based solar cells, however maximum efficiency achieved to date is far less than the predicted value. In this work, a detailed analysis of the poor performance of CdS/p-SnS heterojunction solar cells is carried out. ITO/CdS/p-SnS/Au solar cells with varying thickness of p-SnS absorber layer were made using a thermal evaporation technique. Best conversion efficiency of 0.005% was obtained for the cell having p-SnS layer of thickness 1068nm. Defects present in p-SnS thin films along with the band misalignment at the interface of CdS/SnS layers lead to poor performance of the cell by increasing the trap-assisted tunneling recombinations at the junction. Ideality factor was calculated from the dark J-V characteristics, using the modified piecewise model [5] to quantify the junction characteristics. It was found that the ideality factor has a direct impact on the device performance, with efficiency decreasing as the ideality factor of the junction increases. References: [1] H.Noguchi, A.Setiyadi, H.Tanamura, T.Nagatomo, O.Omoto, Sol. Energ. Mater. Sol. Cells 35 (1994) 325. [2] C.Gao, H.Shen, L.Sun, Z.Chen, Mater. Lett. 65 (2011) 1413. [3] G.H.Yue, D.L.Peng, P.X.Yan, L.S.Wang, W.Wang, X.H.Luo, Alloys Compd. 468 (2009) 254. [4] J.J.Loferski, J. Appl. Phys. 27 (1956) 777. [5] Y.Gupta, P.Arun, JAPED (accepted, 2017). |