Telecentric NUV-DUV irradiator for out-of-contact exposure of large substrates

An ultraviolet radiation source apparatus comprising:

• a mercury arc lamp operating under a predetermined pressure for producing ultraviolet radiation and being an elongated arc having a predetermined length to width ratio;
• a paraboloidal reflector cooperating with said mercury arc lamp to provide a converging ray bundle of said ultraviolet radiation;
• a condenser lens assembly responsive to said converging ray bundle to provide an effective circular source;
• and
• means responsive to said effective circular source to direct a modified form of said effective circular source to a given target area at a given plane.

An optical system for providing an ultraviolet radiation pattern for photolithography, comprising:

• a mercury lamp operating under a predetermined pressure for producing ultraviolet radiation and being an elongated arc of a given length to width ratio;
• a paraboloidal reflector symmetrically surrounding said mercury lamp below its focal point to efficiently collect the ultraviolet radiation from said mercury elongated arc lamp for generating a converging ray bundle with higher marginal irradiance than its center;
• a short focal length condenser lens assembly positioned with respect to said paraboloidal reflector to retrieve said converging ray bundle to provide at an output a predetermined diameter circular pattern indicative of an effective circular source;
• and
• an entrance pupil lens and a collimation lens positioned with respect to said condenser lens assembly to provide at an output a collimated beam of high uniformity and stability for projecting said collimated beam to a mask and wafer out-of-contact to each other and radiate such mask and wafer with said collimated beam.