Via Drilling and Alignment on Flexible subtrates using Laser Technology

Sudhakar Raman Electro Scientific Industries

Abstract:

In the recent years, laser technology has become the method of choice for forming microvias in Flexible circuits as well as chip packaging devices. The trend today in portable electronics is to make them smaller, lighter, thinner and faster with added functionality— at lower cost performance ratio. The trend towards smaller annular rings in the future drives home the point that the laser drilling system's accuracy has to improve constantly. In certain flexible circuit applications, laser processing is the first step in the process, ultimately defining the registration requirements for the subsequent steps.

This paper describes practical experiences with these lasers for drilling both high aspect-ratio through, blind vias as well as micromachining in flexible circuits. A high level view of how the laser processing systems performs alignment is discussed. The improvements in laser beam positioning technology required to support these high-efficiency lasers processing systems is outlined.