Impact of SnS Buffer Layer at Mo/Cu₂ZnSnS₄ Interface

Abstract

Cu2ZnSnS4 (CZTS) compound is a promising candidate for thin‐film solar cells since its constituents are earth abundant and nontoxic. One of the major challenges to obtain a high‐quality CZTS absorber is to overcome the interfacial mismatch and formation of secondary phases between the CZTS and Mo substrate during the sulfurization process. Generally, the CZTS decomposed into Cu2S, ZnS, and SnS phases during sulfurization, and high‐density voids and cracks were observed. These micro‐ or macroreactions changed the stoichiometry of CZTS. In this paper, we present the insertion of a SnS buffer layer at Mo/CZTS interface to inhibit the undesired reaction and improve the thin‐film quality. The insertion of the thin SnS buffer layer prevented the CZTS absorber to contact directly with Mo and suppressed the present of secondary phases, pores and cracks. Crack‐free and smooth morphology was obtained. The cell efficiency was significantly improved.

Voids in Kesterites and the Influence of Lamellae Preparation by Focused Ion Beam for Transmission Electron Microscopy Analyses

“…The identification of such pinholes is important as they are detrimental from a device point of view. The observation of voids in the growth of kesterite materials is something that is common and it has been attributed mostly to Kirkendall effects during the chalcogenation process [44]- [46] and to complex thermodynamic reactions taking place at the Mo interface [47]. As such, the voids seen in the literature have the tendency to be present close to the back contact.…”

“…The first type of voids is natural occurring voids that are evenly coated by CdS during the chemical bath deposition and that are present in the early stages of the FIB preparation and in SEM cross-sectional images. These voids are usually attributed to Kirkendall effects [44]- [46]. The second type of voids, larger and present with a higher amount compared with the natural occurring voids, are the likely results of the FIB preparation of CZTSe TEM lamellae.…”

Theoretical Analysis of Solar Cell Performance with Different Backsurface‐Filed Layers Utilizing Experimental Results of CdS Films Deposited by Pulsed Laser

“…[ 25–27 ] Distinctive works investigated the effect of the BSF on the performance of CZTS‐based solar cells. [ 24,28–30 ] In our present work, PbS and V 2 O 5 have been used for the first time with CZTS as the BSF. These two materials have previously been considered as the BSF with CIGS [ 31 ] and CdTe, [ 32 ] respectively.…”

Improved electrical and optical properties in epitaxial Cd2SnO4 films

“…The combination of these two characteristics makes TCO materials of great significance for the wide application of modern optoelectronic devices, such as transparent-flexible electronics, touch panels, organic light-emitting dioxides. [1][2][3][4][5][6] Indium tin oxide (ITO), as the typical TCO material, is rather one of the popular TCOs used as flat panel displays because of the outstanding electrical and optical properties. 7,8 Other binary TCOs, including SnO 2 and ZnO, 9 are also well known in optoelectronic applications.…”

“…The term transparent conducting oxide (TCO) generally refers to the materials having both high electrical conductivity and high optical transmission. The combination of these two characteristics makes TCO materials of great significance for the wide application of modern optoelectronic devices, such as transparent‐flexible electronics, touch panels, organic light‐emitting dioxides 1–6 . Indium tin oxide (ITO), as the typical TCO material, is rather one of the popular TCOs used as flat panel displays because of the outstanding electrical and optical properties 7,8 .…”