Mitigation of substrate defects in reflective reticles using sequential coating and annealing
AssigneeThe Regents of the University of California
InventorPaul B. Mirkanimi
Life of this patent
Estimating the term…
Abstract
A buffer-layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The buffer-layer is formed by either a multilayer deposited on the substrate or by a plurality of sequentially deposited and annealed coatings deposited on the substrate. The plurality of sequentially deposited and annealed coating may comprise multilayer and single layer coatings. The multilayer deposited and annealed buffer layer coatings may be of the same or different material than the reflecting coating thereafter deposited on the buffer-layer.
Claims22
In a device for use in lithography having a substrate and a reflective multilayer, the improvement compromising:
- a buffer-layer consisting of a plurality of sequentially deposited and annealed layers.
A reticle for extreme ultraviolet lithography, compromising:
- a substrate, and
- a buffer-layer,
- said buffer-layer consisting of a plurality of sequentially deposited and annealed layers.
A method for mitigating the effect of substrate particles on reticles, such as utility in extreme ultraviolet lithography, comprising:
- providing a buffer-layer on the surface of said substrate having an outer surface roughness of not greater than about 0.3 nm, and
- wherein providing the buffer-layer is carried out by sequential coating and annealing of a plurality of layers of material on the substrate.
Dependencies are inferred from the claim text.