Intel Corporation

Hughes Aircraft Company

Hsing-Chien Ma

Pei-yang Yan

Arun Ramamoorthy

Scott R Chegwidden

Kuang-Yeh Chang

Kuan Y Liao

A composite extreme ultraviolet light (EUV) mask absorber structure and method are disclosed to address the structural and processing requirements of EUV lithography. A first mask absorber layer anisotropically etched with minimal etch bias at a relatively fast etch rate, is combined with a highly-selective second mask absorber layer, to produce a mask absorber with desirable hybrid performance properties.

Dual-layer EUV mask absorber with trenches having opposing sidewalls that are straight and parallel

Apparatus and methods to protect a photomask that is used for semiconductor photolithography at wavelengths outside the visible spectrum include a pellicle that is readily retracted during exposure or to provide access to the photomask. The pellicle can be transparent at an inspection wavelength and opaque at an exposure wavelength. In various embodiments, the pellicle is slid, retracted, or pivoted relative to a base aligned with the photomask, thus uncovering the photomask. When overlying the photomask, the pellicle can be secured with magnetic elements, such as magnets or electromagnets. In another embodiment, the pellicle includes a diaphragm having a plurality of shutter leaves that can be opened or closed. Methods of using a pellicle are also described.

Mechanized retractable pellicles and methods of use

Double-metal EUV mask absorber

Apparatus and methods to protect a photomask that is used for semiconductor photolithography at wavelengths outside the visible spectrum include a pellicle that is readily retracted during exposure or to provide access to the photomask. The pellicle can be transparent at an inspection wavelength and opaque at an exposure wavelength. In various embodiments, the pellicle is slid, retracted, or pivoted relative to a base aligned with the photomask, thus uncovering the photomask. When overlying the photomask, the pellicle can be secured with magnetic elements, such as magnets or electromagnets. In another embodiment, the pellicle includes a diaphragm that can be opened or closed. Methods of using a pellicle are also described.

A photolithographic process useful for VLSI fabrication is disclosed for achieving side-wall profile control of poly lines, metal lines, contact and via openings. Layers of a first and second photoresist materials are formed on the poly, metal or oxide-covered substrate. The top layer is patterned by conventional processes to define the final device geometry. The bottom layer is exposed and over-developed to form an overhang structure about the line pattern or the contact/via opening. During the subsequent anisotropic plasma-assisted etching step, some ions or particles are passed obliquely over the overhang and bombard the opening corner, the side-wall and the under-cut area. The plasma-assisted etching step not only forms the poly or metal lines, or the contact or via opening, but also results in an opening with rounded corners and a smoothly tapered side-wall profile. The subsequent metal film deposition step results in a uniform film thickness around the edges of the opening. The process thus alleviates the problem of high contact resistance previously encountered as a result of dry etching the contact or via openings.

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Fremont, CA, United States of America

Hsing-Chien Ma