摘要 |
The present invention is a method for drilling a subminiature through hole through a substrate. The through holes of the present invention are preferably drilled through an alumina substrate which is essentially impervious to aqueous electrolytes and blood over long periods of storage in potentially reactive environments. The holes are drilled by directing a sealed type CO2 laser at a predetermined position located on the substrate, energizing the laser at a power of approximately 75 to 225 watts, such that the laser beam focuses on the substrate at the predetermined position, and treating the substrate after the laser has drilled the hole. |