Desarrollo de películas conductoras de nanotubos de carbono sinterizados por manufactura avanzada para celdas solares

Abstract

This research focuses on the development of single-walled carbon nanotube (SWCNT) conductive films through advanced manufacturing for solar cells. This work aims to analyze SWCNT conductive tracks deposited on silicon wafers via doctor blade deposition and localized CO2 laser sintering, evaluating its morphology, structure, and electrical behavior. The need to reduce thermal stress in photovoltaic devices is justified under the hypothesis that selective sintering optimizes inter-tubular connectivity without degrading the substrate. During the development, a thixotropic aqueous paste was synthesized and deposited via doctor blade technique onto wafers with an Ethyl Vinyl Acetate (EVA) mask. Subsequently, thermal sintering was executed using a CO2 laser under specific operating conditions that were calculated through a simplified thermal model. The results demonstrated that one optimum condition occurs at a sintering temperature of 119.5°C, allowing for an effective removal of the dispersing agents and promoting the formation of “sintering necks” which was observed by scanning electron microscopy SEM. A sheet resistance of 44.8 Ω was obtained with a standard deviation of less than 5%, validating a stable ohmic response. The results demonstrate that laser sintering significantly reduces electrical resistivity while operating at much lower temperatures than conventional methods, providing important technical, energy, and environmental advantages. In addition, the development protocol strengthens local research capabilities in applied nanotechnology and contributes to the Sustainable Development Goals related to clean energy and sustainable manufacturing. Keywords: Advanced manufacturing, Thin films, Morphological characterization, Sheet resistance, Inter-tubular connectivity.