Objective for EUV microscopy, EUV lithography, and x-ray imaging

摘要

Disclosed is an imaging apparatus for EUV spectroscopy, EUV microscopy, EUV lithography, and x-ray imaging. This new imaging apparatus could, in particular, make significant contributions to EUV lithography at wavelengths in the range from 10 to 15 nm, which is presently being developed for the manufacturing of the next-generation integrated circuits. The disclosure provides a novel adjustable imaging apparatus that allows for the production of stigmatic images in x-ray imaging, EUV imaging, and EUVL. The imaging apparatus of the present invention incorporates additional properties compared to previously described objectives. The use of a pair of spherical reflectors containing a concave and convex arrangement has been applied to a EUV imaging system to allow for the image and optics to all be placed on the same side of a vacuum chamber. Additionally, the two spherical reflector segments previously described have been replaced by two full spheres or, more precisely, two spherical annuli, so that the total photon throughput is largely increased. Finally, the range of permissible Bragg angles and possible magnifications of the objective has been largely increased.

主权项

1. An adjustable apparatus for forming an image of an object, the apparatus comprising:
a. at least one pair of concentric spherical reflectors wherein the reflectors share a common center and wherein each pair includes a convex reflector containing a radius of curvature R1 and a Bragg angle θ1, and a concave reflector containing a radius of curvature R2 and a Bragg angle θ2; wherein the spherical reflectors are concentric with a mathematical sphere that contains a radius RT, wherein:
RT=R1 cos(θ1)=R2 cos(θ2); b. a ray pattern established by reflection of radiation from the object on the reflectors; and c. an axis of symmetry of the ray pattern from the object, through the common center, to an image of the object and wherein the apparatus is configured to allow the ray pattern to be rotated about the axis.