Abstract

Biomedical and microelectronic devices such as microinjectors and interconnects require line patterns to be fabricated on their surface. The process to pattern such surfaces should consider the requirements such as chemical inertness and biocompatibility. Laser Induced Forward Transfer (LIFT) is a simple direct write technique which offers the ability to pattern a substrate by localized deposition of material. In LIFT, a laser beam is focused through donor substrate (DS) coated with thin film to deposit on the acceptor substrate (AS) to be patterned. In this research project, a new laser based micropatterning method combining LIFT and laser interferometry for depositing periodic line patterns on a substrate has been proposed. Considering biocompatibility, glass has been selected as the acceptor substrate where a laser beam was focused on a gold film to get deposited on it. Theoretical modeling has been done to predict the laser and optical parameters on the dimensions of the gold line patterns. Also the effect of refractive index and thickness of the DS on the patterned dimensions has been analyzed. Experiments were done to deposit patterns of widths ranging from 4 to 10 o m with the pitch between 8 and 20 o m . Experiments were also done by varying the feed rate and dwell time of scanning to achieve continuity in deposition and up to 700 o m length i.e. three times the focused spot size have been deposited. With the proposed method, pattern dimensions on the substrate can be easily modified by making simple changes to the optical setup