Optical projection lens system

Apparatus comprising:

• a microlithography projection lens system having a numerical aperture of 0.7 or more and comprising refractive lens elements positioned to image radiation from a mask to a wafer,
• the refractive lens elements consisting essentially of:
• a first lens group following the mask, having positive refractive power, and comprising only one convex portion;
• a second lens group following the first lens group, having negative refractive power, and comprising only one constriction portion where radiation propagating from the object side to the image side has a minimum diameter;
• and
• a third lens group following the second lens group, having positive refractive power, and comprising only one convex portion.

A method comprising:

• directing UV-radiation to a mask having a pattern;
• exposing a light-sensitive layer on a wafer with radiation emerging from the mask;
• developing the light-sensitive layer on the wafer,
• wherein the exposing comprises imaging the radiation from the mask to the wafer with a numerical aperture of 0.7 or more and with the imaged radiation having only one clearly defined local minimum in diameter between the mask and the wafer and passing through at least one aspherical surface.

Apparatus comprising:

• means for directing UV-radiation to a mask having a pattern;
• and
• means for exposing a light-sensitive layer on a wafer with radiation emerging from the mask,
• wherein the exposing comprises imaging the radiation from the mask to the wafer with a numerical aperture of 0.7 or more and with the imaged radiation having only one clearly defined local minimum in diameter between the mask and the wafer and passing through at least one aspherical surface.

Apparatus comprising:

• a mask holder configured to support a mask having a pattern,
• an excimer laser configured to illuminate the mask with radiation at about 248 nm or less;
• and
• a microlithography optical projection lens system configured to direct radiation emerging from the mask to a wafer with a numerical aperture of 0.7 or more,
• the radiation passing through refractive lens elements of the microlithography optical projection lens system, having a diameter that varies between the mask and the wafer as it passes through the refractive lens elements, and forming an image of the mask pattern on the wafer,
• wherein the refractive lens elements are positioned to image the radiation from the mask to the wafer with only one clearly defined local minimum in the diameter of the radiation.

Apparatus comprising:

• a microlithography projection lens system comprising refractive lens elements for imaging radiation from a mask to a wafer,
• the microlithography projection lens system has a numerical aperture of 0.7 or more and only one clearly defined constriction portion where the radiation has a minimum diameter,
• wherein the microlithography projection lens system is configured for use with an excimer laser light source operating at or below about 248 nm, and
• wherein the refractive lens element closest to the mask has negative refractive power.

Apparatus comprising:

• a microlithography projection lens system comprising refractive lens elements for imaging radiation from a mask to a wafer,
• the microlithography projection lens system has a numerical aperture of 0.7 or more and only one clearly defined constriction portion where the radiation has a minimum diameter,
• wherein the microlithography projection lens system is configured for use with an excimer laser light source operating at or below about 248 nm,
• wherein the refractive lens elements comprise a first lens group having positive refractive power, a second lens group following the first lens group and having negative refractive power, and a third lens group following the second lens group and having positive refractive power,
• wherein the clearly defined constriction portion is located within the second lens group, and
• wherein the first lens group comprises at least five elements each having positive refractive power.

Apparatus comprising:

• a microlithography projection lens system comprising refractive lens elements for imaging radiation from a mask to a wafer,
• the microlithography projection lens system has a numerical aperture of 0.7 or more and only one clearly defined constriction portion where the radiation has a minimum diameter,
• wherein the microlithography projection lens system is configured for use with an excimer laser light source operating at or below about 248 nm,
• wherein the refractive lens elements comprise a first lens group having positive refractive power, a second lens group following the first lens group and having negative refractive power, and a third lens group following the second lens group and having positive refractive power,
• wherein the clearly defined constriction portion is located within the second lens group, and
• wherein the second lens group comprises at least two elements each having negative refractive power and positioned between the clearly defined constriction portion and the wafer.

Apparatus comprising:

• a microlithography projection lens system comprising refractive lens elements for imaging radiation from a mask to a wafer,
• the microlithography projection lens system has a numerical aperture of 0.7 or more and only one clearly defined constriction portion where the radiation has a minimum diameter,
• wherein the microlithography projection lens system is configured for use with an excimer laser light source operating at or below about 248 nm, and
• wherein the microlithography projection lens has a maximal optically free diameter greater than 0.2 times a distance from an object side object plane and an image side image plane into which said object plane is imaged by said optical projection lens.