Investigación numérica del proceso de sinterizado laser de pistas de cobre en celdas solares de Hetero-Unión de Silicio

Abstract

CONDITION FOR PUBLICATION OF PROJECT. The manufacturing of high-efficiency solar cells presents a challenge regarding the use of new materials and advanced manufacturing processes that allow the formation of conductive tracks (fingers and busbars) on silicon-based solar cells. Selective laser sintering (SLS) presents itself as an alternative due to its high precision and localized heating. This process allows for proper metallization of solar cells avoiding thermal damage. The control of sintering parameters such as laser power, speed and laser beam diameter are critical, and any variation in these can affect material integrity of the solar cell. The optimization of these variables in the metallization of silicon heterojunction solar cells (SHJ) is proposed through Computational Fluid Dynamics. Laser irradiation was modeled as a heat flux with Gaussian distribution and the thermal physical properties of the materials as temperature dependent. Optimal cases were found for sintering temperatures of 280 °C for the copper tracks, while 250 °C as the maximum allowable temperature for the copper-silicon interface. The relevance of this study is based on the need to migrate from empirical approaches based on trial and error to a predictive engineering technique. Keywords: laser sintering, copper nanoparticles, energy density, scanning speed, thermal tolerance, laser beam