Investigation of valence plasmon excitations in GMZO thin film and their suitability for plasmon-enhanced buffer-less solar cells. (15th January 2019)

• Record Type: Journal Article
• Authors: Garg, Vivek; Sengar, Brajendra S.; Kumar, Amitesh; Siddharth, Gaurav; Kumar, Shailendra; Mukherjee, Shaibal
• Is Part Of: Solar energy. Volume 178(2019)
• Page Start: 114
• Page End: 124
• Publication Date: 2019-01-15
• Subjects: Plasmons -- UPS -- CIGSe -- Ultrathin solar cells; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2018.12.017
• Languages: English
• ISSNs: 0038-092X

Abstract

Graphical abstract: Highlights: A novel approach to generate plasmons in GMZO thin film is reported. Plasmon generation in GMZO is investigated using UPS, FESEM, and SE measurements. Suitability of GMZO for buffer-less solar cells is probed using band-offset studies. Devices performance parameters with varying band-offsets are theoretically estimated. Using measured material and CBO parameters device performance is predicted. Abstract: The approach of eliminating buffer layer in conjunction with plasmon-enhanced transparent conduction oxide (TCO) layer is an attractive methodology to realize low-cost ultrathin buffer-less solar cells (SCs) by introducing plasmon-enhanced absorption and reduced fabrication steps. Here, we report a novel method to generate wide-band sputter-stimulated plasmonic feature in Ga-doped-MgZnO (GMZO) thin-films, which are observed due to the different metallic and metal-oxide nanoclusters formation. Through an extensive analysis of photoelectron spectroscopy, spectroscopic ellipsometry, and field-emission scanning electron microscope measurements the evaluation of plasmonic features and correlation of them with various nanoclusters inside GMZO thin-film is performed. Additionally, the suitability and expected performance of plasmon-enhanced GMZO thin-film based buffer-less SCs are probed through; 1) band-offset analysis at the plasmon enhanced-GMZO/CIGSe heterojunction; 2) simulation studies to analyze the effect of conduction band-offset (CBO) on the performance of the buffer-less SCs; 3) predicting the performance of the buffer-less SC using the parameters of GMZO thin-films with varying CBO, and 4) envisaging the concept of ultrathin buffer-less SC with calculated CBO and absorber layer thickness (300 nm) for ultrathin SCs. Moreover, at the experimentally calculated band-offset with ultrathin absorber layer thickness (300 nm), theoretically calculated buffer-less SC performance parameters estimated to be open-circuit voltage (Voc ): 0.75 V, short-circuit current density (Jsc ): 17.29 mA/cm 2, fill-factor (FF): 80.5%, and efficiency (Eff ): 10.46%.