Additive manufacturing plays a crucial role in next-generation solar cells, enabling multi-layer deposition required for heterojunction and intermediate band solar cells. In this context, laser sintering provides precise, localized heating mechanism, minimizing thermal damage to surrounding regions. This study presents a numerical simulation of copper metallization via CO? laser sintering, focusing on selecting operating parameters to enhance sintering efficiency while reducing substrate damage.

A 3D Computational Fluid Dynamics-conjugate heat transfer model was developed in ANSYS Fluent to capture the thermal behavior during CO? laser sintering. The thermal analysis considers heat transfer along with temperature-dependent physical properties. User-Defined Functions (UDFs) introduce source terms into the energy and mass transport equations for representation of the process.

The model predicts temperature distributions and sintering depths, and results were validated against experimental data. Two processing conditions, 8?W at 10?mm/s and 5?W at 4?mm/s, were identified as choices for optimal sintering of the copper contacts. Parametric analysis showed that optimal sintering depends on both laser energy density and the laser spot-to-line width ratio. The findings offer design guidelines for precise, low-temperature copper metallization in next-generation photovoltaic devices.

This work advances numerical modeling for laser sintering for metal nanoparticles, contributing to high-precision copper metallization for advanced electronics and photovoltaics. The findings support future improvements in solar cell efficiency and cost reduction in manufacturing solar cells and other optoelectronic devices.