High precision scribing of solar cell films by a picosecond laser

Abstract

In this paper, the feasibility of thin-film solar cells scribing via a picosecond (ps) laser is investigated. The optical and thermal properties of thin films are studied first. Then experiments are performed with different wavelengths and average powers and results are analyzed for process parameter optimization. The scribed slots are measured using a surface profilometer and a scanning electron microscope (SEM). Using the optimized laser parameters, the ablation depths of the slots are accurate within 0.1 μ.m tolerance, the edges are sharp without distortions and slot bottoms are flat. These slots are precisely machined with a high speed, which makes ps laser scribing of solar cells a promising technique.In this paper, the feasibility of thin-film solar cells scribing via a picosecond (ps) laser is investigated. The optical and thermal properties of thin films are studied first. Then experiments are performed with different wavelengths and average powers and results are analyzed for process parameter optimization. The scribed slots are measured using a surface profilometer and a scanning electron microscope (SEM). Using the optimized laser parameters, the ablation depths of the slots are accurate within 0.1 μ.m tolerance, the edges are sharp without distortions and slot bottoms are flat. These slots are precisely machined with a high speed, which makes ps laser scribing of solar cells a promising technique.