ABLATION OF POLYMERS WITH EXCIMER LASERS

Laser radiation in the UV region offers some unique and useful reactions with organic polymers. Early sources of UV energy - filtered mercury, mercury-xenon and deuterium lamps - were used with elliptical mirrors and fly's-eye lenses to maximize use of all ray bundles for uniformity and intensity. However, these sources typically deliver exposure intensities below the photoablation thresholds of organic polymers and are, therefore, unsuitable for ablation reactions. Excimer lasers were the first UV light sources to deliver high average power, an attribute that helped propel them from basic research to production. The main topics are advantages of excimer lasers, excimer laser basics, light absorption mechanisms, excimer laser applications, and photolithography.