Photopolymers based on the triazeno chromophore group (-N=N-N<) have been developed. The absorption properties can be tailored for a specific irradiation wavelength (e.g. 308 nm XeCl laser). The photochemical exothermic decomposition yields high energetic gaseous products which are not contaminating the surface. The polymer can be structured with high resolution. No debris has been found around the etched corners. Maximum ablation rates of about 3 μm / pulse were achieved due to the dynamic absorption behavior (bleaching during the pulse). No physical or chemical modifications of the polymer surface could be detected after irradiation at the tailored absorption wavelength, whereas irradiation at different wavelengths resulted in modified (physical and chemical) surfaces. The etching of the polymer starts and ends with the laser pulse, shown by ns-interferometry, confirming that the acting mechanism is mainly photochemical. TOF-MS revealed fragments which are also totally compatible with a photochemical decomposition mechanism.
|Number of pages||8|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - 1 Dec 1997|
|Event||ALT 1997 International Conference on Laser Surface Processing - Limoges, France|
Duration: 8 Sep 1997 → 12 Sep 1997
- Excimer laser
- Laser ablation