EUV condenser with non-imaging optics

A condenser for use in the extreme ultraviolet wavelength region comprising:

• a collector having a predetermined reflective surface which does not image a source and provides a predetermined irradiance distribution;
• a shaper, said shaper receiving electromagnetic radiation reflected from said collector and shapes the electromagnetic radiation into a collimated illumination field of desired shape;
• a plurality of facets formed on said shaper, said plurality of facets providing a desired irradiance within the illumination field;
• and
• objective optics forming an image of the illumination field on a reticle.

A condenser for use in an extreme ultraviolet illumination system comprising:

• non-imaging means for collecting electromagnetic radiation from a source and forming a desired irradiance distribution;
• shaper means, positioned to receive electromagnetic radiation from said non-imaging means, for collimating the electromagnetic radiation and forming an illumination field having a desired shape;
• and
• facet means, associated with said shaper means, for forming a uniform illumination over the desired illumination field.

A condenser for use in the extreme ultraviolet wavelength region comprising:

• a collector having a predetermined reflective surface providing a predetermined irradiance distribution, said collector having the predetermined reflective surface defined by the following differential equations:
• 2 ⅆ ϕ ⅆ x = ⁢ ± xE ⁡ ( x ) ρ ⁡ ( α ) / ( ϕ ) ⁢ sin ⁡ ( ϕ ) ⅆ r ⅆ ϕ = ⁢ ⅆ ϕ ⅆ x ⁢ r ⁢ ⁢ tan ⁡ ( α )
• where,
• E(x) is irradiance,
• ρ is the reflectance,
• I(Φ) is the intensity,
• r is a radial distance between a source and the non-imaging optical element reflective surface,
• Φ is an angle between the radial distance r and a perpendicular line from an illumination plane extending through the source,
• θ is an angle between a perpendicular line from an illumination plane and a ray reflected from the non-imaging optical element reflective surface,
• x is the distance along an illumination plane from the intersection of the illumination plane and a perpendicular line extending through the source and a ray reflected from the non-imaging optical element reflective surface, and α=(Φ−θ)/2;
• a shaper, said shaper receiving electromagnetic radiation reflected from said collector and shaping and collimating the electromagnetic radiation into an illumination field having a desired shape;
• a plurality of facets formed on said shaper, said plurality of facets providing a desired irradiance within the illumination field;
• and
• objective optics forming an image of the desired illumination field on a reticle.

An illumination system for use in photolithography using electromagnetic radiation in the extreme ultraviolet wavelength region comprising:

• a source of electromagnetic radiation, the electromagnetic radiation having a wavelength less than two hundred nanometers;
• a non-imaging collector positioned to receive the electromagnetic radiation from said source, said non-imaging collector having a shaped reflective surface reflecting electromagnetic radiation creating a predetermined irradiance distribution;
• a shaper positioned to receive the electromagnetic radiation reflected from said non-imaging collector, said shaper collimating the electromagnetic radiation and forming an illumination field having a predetermined shape;
• and
• objective optics positioned to receive the electromagnetic radiation from said shaper, said objective optics imaging the illumination field forming a desired irradiance with a desired angular distribution,
• whereby the image of a reticle is projected onto a photosensitive substrate.

A method of illuminating a reticle with extreme ultraviolet electromagnetic radiation comprising:

• forming a desired irradiance distribution of electromagnetic radiation with a reflective non-imaging optic element;
• collecting the electromagnetic radiation reflected from the reflective non-imaging optical element;
• redirecting the electromagnetic radiation collected form the reflective non-imaging optical element forming collimated electromagnetic radiation;
• and
• shaping the electromagnetic radiation such that when imaged a uniform illumination having a desired angular distribution is formed over an illumination field having a desired shape.