WS2: A New Window Layer Material for Solar Cell Application

• Published in: Scientific reports 2020-01, Vol.10 (1), p.771-771, Article 771
• Main Authors: Bin Rafiq, Md. Khan Sobayel, Amin, N., Alharbi, Hamad F., Luqman, Monis, Ayob, Afida, Alharthi, Yahya S., Alharthi, Nabeel H., Bais, Badariah, Akhtaruzzaman, Md
• Format: Article
• Language: English
• Subjects: 142/136; 639/301; 639/4077/909; Glass substrates; Humanities and Social Sciences; Investigations; multidisciplinary; Photovoltaic cells; Photovoltaics; Science; Science (multidisciplinary); Solar cells; Thin films; Tungsten
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-57596-5

Radio frequency (RF) magnetron sputtering was used to deposit tungsten disulfide (WS 2 ) thin films on top of soda lime glass substrates. The deposition power of RF magnetron sputtering varied at 50, 100, 150, 200, and 250 W to investigate the impact on film characteristics and determine the optimized conditions for suitable application in thin-film solar cells. Morphological, structural, and opto-electronic properties of as-grown films were investigated and analyzed for different deposition powers. All the WS 2 films exhibited granular morphology and consisted of a rhombohedral phase with a strong preferential orientation toward the (101) crystal plane. Polycrystalline ultra-thin WS 2 films with bandgap of 2.2 eV, carrier concentration of 1.01 × 10 19  cm −3 , and resistivity of 0.135 Ω-cm were successfully achieved at RF deposition power of 200 W. The optimized WS 2 thin film was successfully incorporated as a window layer for the first time in CdTe/WS 2 solar cell. Initial investigations revealed that the newly incorporated WS 2 window layer in CdTe solar cell demonstrated photovoltaic conversion efficiency of 1.2% with V oc of 379 mV, J sc of 11.5 mA/cm 2 , and FF of 27.1%. This study paves the way for WS 2 thin film as a potential window layer to be used in thin-film solar cells.