Fine line screen printed silver electrodes for copper electrodeposition

Abstract

Purpose In this paper, results of the studies on the copper deposition on screen-printed fine-line front electrode of the solar cell were presented. The silver consumption is an important problem according to growing silver prices. The proposed solution of those problems might be printing of a very thin silver seed layer and subsequent copper plating. This process can be an alternative for typically used screen printing. The purpose of this study was the optimization of the finger path fabrication process to obtain required geometric of fingers for copper deposition. Design/methodology/approach In this paper, double-step metallization process was analyzed. The first step of an electrode formation is screen printing, the second one is copper electrodeposition. Presented investigations were focused on the optimization of the finger path fabrication process to obtain required geometric dimensions and sharp border of fingers. The morphology of the electrodes was characterized by scanning electron microscope before and after copper deposition. The X-ray analysis of elemental arrangement and cross-section profiles of fingers were made using energy-dispersive X-ray fluorescence spectrometer. Findings Presented investigations were focused on the optimization of the finger path fabrication process to obtain required geometric dimensions and sharp border of fingers without any silver particles. The main problem of non-uniform silver paste distribution close to the border of printed finger paths was eliminated by selection of appropriate paste and printing parameters. The obtained coatings were soft, ductile and bright. Originality/value The novelty of the presented approach is modification of the printing parameters, especially for copper deposition. In this paper, the reasons of the widening of electrodes during the copper deposition process is analyzed.