Abstract: Optical Projection System and Method for Photolithography. A lithographic immersion projection system and method for projecting an image at high resolution over a wide field of view. The projection system and method include a final lens which decreases the marginal ray angle of the optical path before light passes into the immersion liquid to impinge on the image plane.

Abstract: A method for designing, an optical assembly (16) for transmitting an illumination beam (334) includes the steps of selecting an optical element (32), selecting at least two rays (356) from the illumination beam (334), and calculating a contrast of the at least two rays (356) that exit the optical element (32) based on the at least two rays (356). With this design, one or more parameters of the optical element (32) can be adjusted and the contrast recalculated until the performance characteristics of the optical element (32) are optimized. For example, the optical element (32) can include a crystalline first optical component (350) and a crystalline second optical component (352) that are stacked on each other and that are rotated relative to each other a rotation angle (358). The first optical component (350) has a FOC thickness (360) and a FOC entry curvature (362) and the second optical component (352) has a SOC thickness (366) and a SOC entry curvature (368).

Abstract: A catadioptric projection optical system for use in photolithography used in manufacturing semiconductors having a quarter waveplate following a reticle and multiple aspheric surfaces and calcium fluoride lens elements. A quarter waveplate following the reticle eliminates asymmetry in reticle diffraction caused by polarized illumination. The use of additional aspheric surfaces reduces the number of lens elements and aids in reducing aberrations. Calcium fluoride elements are used in the lens group adjacent the wafer to help minimize compaction. In one embodiment, only calcium fluoride material is used. The present invention provides a projection optics system having a numerical aperture of 0.75 for use with wavelengths in the 248, 193, and 157 nanometer range. The object and image locations are separated by a predetermined distance, making possible retrofitting of older optical systems.

Abstract: An on-axis through the lens optical alignment system for use in semiconductor manufacturing using step and scan photolithographic techniques. An optical alignment system uses a partially common path with the projection optics (16) optical axis (38) in order to detect alignment targets on a wafer (10) and a mask (20). The relative position of the mask (20) and wafer (10) is detected during a single simultaneous scan, and the mask (20) and wafer (10) are resultantly aligned. This provides advantages over prior art multiple channel off-axis through the lens alignment systems and single channel non-through the lens alignment systems. A detailed optical apparatus (60) is disclosed.

Abstract: An all reflective ring field projection optic system for use in scanning photolithography used in the manufacture of semiconductor wafers. The projection optics are designed for wavelengths in the extreme ultraviolet ranging from 11 to 13 nm to provide an arcuate image field for a reduction step and scan photolithography system. A sequence or configuration of mirrors from the long conjugate end to the short conjugate end consists of a convex, concave, convex, and concave mirror with an aperture stop being formed at or near the second convex mirror. This sequence of mirror powers provides a relatively large image field size while maintaining a relatively compact reticle wafer distance of less than 900 mm. The projection optics form an instantaneous annual field of up to 50 mm.times.2 mm at the wafer, permitting scanning to cover a field on a wafer of at least 50 mm.times.50 mm, greatly increasing throughput. The optical projection system can print features as small as 0.05 microns.

Abstract: An optical projection reduction system used in photolithography for the manufacture of semiconductor devices having a first mirror pair, a second field mirror pair, and a third mirror pair. Electromagnetic radiation from a reticle or mask is reflected by a first mirror pair to a second field mirror pair forming an intermediate image. A third mirror pair re-images the intermediate image to an image plane at a wafer. All six mirrors are spherical or aspheric and rotationally symmetrical about an optical axis. An annular ring field is obtained, a portion of which may be used in a step and scan photolithography system. In another embodiment, weak refracting elements are introduced to further reduce residual aberrations allowing a higher numerical aperture. In the catoptric embodiment of the present invention, a numerical aperture of 0.25 is obtained resulting in a working resolution of 0.03 microns with electromagnetic radiation having a wavelength of 13 nanometers.

Abstract: A catadioptric optical reduction system for use in the photolithographic manufacture of semiconductors having a concave mirror operating near unit magnification, or close to a concentric condition. A lens group before the mirror provides only enough power to image the entrance pupil at infinity to the aperture stop at or near the concave mirror. A lens group after the mirror provides a larger proportion of reduction from object to image size, as well as projecting the aperture stop to an infinite exit pupil. An aspheric concave mirror is used to further reduce high order aberrations. The catadioptric optical reduction system provides a relatively high numerical aperture of 0.7 capable of patterning features smaller than 0.35 microns over a 26.times.5 millimeter field. The optical reduction system is thereby well adapted to a step and scan microlithographic exposure tool as used in semiconductor manufacturing.

Abstract: An unobscured catadioptric optical reduction system wherein all refractive elements are made of the same material. From its long conjugate end to its short conjugate end the system comprises a first lens group, a beamsplitter, a second lens group, a mirror and a third lens group arranged so that radiation entering the system at its long conjugate end passes through the first lens group, the beamsplitter, the second lens group, and is reflected by the mirror back through the second lens group and is reflected by the beamsplitter through the third lens group. Aberrations of the mirror are corrected by the refractive elements. Lateral color correction is obtained by balancing the power of the first lens group against the power of the third lens group.