On the new reliable devices measuring the curing and photoresist effective radiation

The ultraviolet radiation between approximately 180 nm and 400 nm and the visible light up to 480 nm is ly used today in many industrial processes for curing lacquers, inks and different coating systems. In the radiation curing equipments, different lamp systems with elliptical or parabolic reflectors with intense high or medium pressure lamps with xenon or mercury as filling gas are applied. The cure processes are based on the polymerisation reactions, in which by absorption of uv- and blue radiation in the photoinitiators the radicals can be free enabling the monomers being reactive to polymeres. In order to accelerate the cure processes, very high effective uv irradiances on the material surface up to 100,000 2 should be applied. The distance between lamp arrangements and material is approximately 2Omm-6Omm causing an operating temperature up around 200°C or more. In the photolithography the temperature can be between 80°C and 100°C. High stable and very flat radiometer heads are necessary for these applications. Up to now, there were only a small number of radiometer manufacturers on this field. The radiometers available consist of a radiation collecting optics, a filter set and a semiconductor detector built-in in a metal housing. Under intense irradiation directly on the housing, the aging of all optical components is enormous making a further accurate measurement impossible after a short measuring time. This paper reports firstly on the interrelation between radiation and materials to be cured and general aspects of methods for determinations of cure-effective radiation intensity. In the main chapter, measuring problems in a curing production line will be described and a new state-of the-art measuring equipment will be presented.