PHOTOABLATION AND MICROSTRUCTURING OF POLYESTERCARBONATES AND THEIR BLENDS WITH A XECL EXCIMER-LASER

The growing held of microtechnology creates a need for new methods of structuring affordable materials. Excimer ablation lithography (EAL) h as been introduced as a new method for producing microstructures. The ablation and microstructuring behavior of bis-phenol-polycarbonate-A, several polyestercarbonates and their blends in varying proportions, w ere investigated by using the radiation of a XeCl excimer laser. It wa s found that a minimum content of polyester, either in the co-condensa te or in the blend, is necessary to obtain transparent structures in t he irradiated film for irradiation at 308 nm. When recorded as a funct ion of the molar fraction of the polyester, the etch rate passes throu gh a local maximum and consecutively decreases with increasing content of the polyester group in the polymer bulk. Microstructures with a re solution in the sub-micron scale were obtained by EAL, and the resulta nt structures were made visible and analyzed using an atomic force mic roscope (AFM).