Low-Temperature Metallization of HJT Solar Cells using Electrochemical Printing

Abstract

Additive manufacturing (otherwise known as 3D printing) has revolutionized industrial rapid prototyping with inherent design flexibility. Localized electrochemical deposition/etching is an increasing investigated process for the additive fabrication of metal components due to the benefits of room temperature operating conditions, no requirement for expensive vacuums and equipment, as well as no requirement of other secondary processes observed in the current commercially available 3D printing – which are based on laser melting. Localized electrochemical deposition/etching, as an additive manufacturing process, relates to the electroforming for creating three-dimensional structures of metal deposits by reducing metal ions in an electrolytic solution onto an electrically conductive substrate. Hence, achieving a deposition/etching on a substrate requires a conductive substrate to have an electrical circuit through which an external electric current source could be applied. Hence, laser-induced techniques could be used to achieve metal deposits on a non-conductive substrate since the laser beam alters the electronic structure of the surface of the substrate to induce a local potential at the focal area, which thus becomes the catalytic centre for metal deposition. This research investigates the potential of localized electrochemical printing (deposition and etching) as an additive manufacturing technique. The electroetching on copper substrate and other common metal (zinc, brass and steel) substrates is demonstrated. The developed electrochemical-based metal Etcher device in the Laboratory for Energy and Nano Sciences (LENS) successfully demonstrated to possess subtractive capabilities on common metals. An etching rate of 10 mm/min was achieved with a resolution of 0.5 mm on all metal substrates utilized in the experiments. In addition, the Etcher also successfully electroetched copper-plated PCB plate, which paves a potential utilization in microelectronics applications and other technological applications.

Date of Award	Jul 2022
Original language	American English