Eur. Phys. J. Plus (2015) 130: 16
https://doi.org/10.1140/epjp/i2015-15016-6

Regular Article

Ablation model for semiconductors and dielectrics under ultrafast laser pulses for solar cells micromachining

Polo Fotovoltaico Veneto, Dipartimento di Ingegneria dell’Informazione, Università degli Studi di Padova, Via Gradenigo 6, 35131, Padova, Italy

^* e-mail: paolo.villoresi@dei.unipd.it

Received: 22 September 2014
Revised: 19 December 2014
Accepted: 7 January 2015
Published online: 30 January 2015

Abstract

Ultrafast laser pulses provide a new tool for material processing. The ultrafast regime leads to nonlinear absorption and nonthermal interaction with the target yielding significant advantages in solar cells micromachining over traditional mechanical or Q-switched laser processes: high process speed, high energetic efficiency, reduced heat affected zone (HAZ), high quality and precision of the realized structures. Therefore, a description of the dominant physical processes underlying the ultrafast laser-matter interaction is needed to develop a simplified model able to provide an explanation of the different aspect of the process. This paper provides an overview of the fundamental equations governing the laser-material interaction process in a typical dielectric-semiconductor structure and discusses the solution on a 3D axisymmetric domain obtained with a finite element method (FEM) software applied to the problem of selective dielectric delamination in PV solar cells.