Process Date: November 2000

75-micron holes drilled in 0.015" ceramic (alumina) using a Synrad  Evolution 240.

The thermal brittleness of ceramics resulting from localized heating means that the heat input must be carefully controlled during processing. This translates to using the laser in a pulsed mode. In this case, a 75-micron, 0.003" diameter hole has been drilled in 0.015"-thick alumina (Al203) using 2 pulses of 500 ms. The key to successful ceramic processing is to maximize peak power density and optimize pulsing parameters. Another significant factor in the outcome of this application is the role of the assist gas. The assist gas pressure affects the spread of the expelled ceramic above the hole, and prevents adhesion of dross to the exit of the hole. The gas also shields the focusing optic from debris that is forcefully ejected from the hole or scribe. Additionally, the gas type can enhance the process on a chemical level.
The use of lasers to machine ceramics for the electronics industry is on the rise - a result of increased availability of laser technology and the expansive knowledge base that now exists for ceramic processing within the laser and electronics communities. Cutting, drilling, and scribing of ceramic require a better understanding of both the laser and the process than many other applications. However, understanding and suitable adjustment of processing parameters will lead to high quality, repeatable results. In fact, ceramic processing has become increasingly routine, pushing the limits of speed and feature size further and further.