International Congress on Applications of Lasers & Electro Optics (ICALEO)
This study analyzes laser processing of glass-based printed circuit boards which have the capability to replace conventional substrate materials when electronics are required to operate at elevated temperatures. There is significant potential for glassbased circuit boards within the field of aerospace and electric mobility. The new circuit board concept consists of thin copper-coated borosilicate glass with thicknesses ranging from 150 μm to 500 μm. Conventional mechanical processing of this new circuit boards induces stress on the thin glass which can lead to damage of the substrate. Therefore, laser processing with a picosecond laser source is suggested as a tool within the production process of the new circuit boards. Two necessary processes are investigated using a pulsed picosecond laser with a pulse duration of 7 ps at a wavelength of 515 nm. Precise drill-holes for vertical connections of multilayer boards were produced where chipping at the cutting edge must be avoided. Selective ablation of the copper coating was performed to generate the electrical circuits. The results show that a welldefined ablation process is crucial to achieve adequate electrical isolation without damaging the glass substrate. The study also underlines the huge potential of laser processing with picosecond laser sources, which have proven to be a versatile instrument to drill thin glass and generate electrical circuits by selective ablation.