Stock material or miscellaneous articles – Composite – Of inorganic material
Patent
1992-12-31
1994-11-08
Ryan, Patrick J.
Stock material or miscellaneous articles
Composite
Of inorganic material
428192, 428210, 428702, 428704, 430 5, 378 35, B32B 900
Patent
active
053625757
ABSTRACT:
A membrane is supported at its edge by an annular, tapered skirt structure. The skirt strengthens the attachment of the membrane to the support ring and reinforces the edge region where the membrane would otherwise tend to fail. Stress concentrations are reduced by providing a skirt or featheredge, on the interior side of the skirt, that meets the membrane at a relatively small effective contact angle. In a preferred embodiment, the membrane is made by depositing a polysilicon layer on the surface of a substrate of silica-based glass. A portion of the substrate is removed by an isotropic, selective etchant, such that a portion of the polysilicon layer remains as a free-standing, tensile film supported by a remaining portion of the substrate.
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G. K. Celler, et al., "Masks for x-ray lithography with a point source stepper," J Vac. Sci Technol. B 10(6), Nov/Dec 1992, 3186-3190.
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AT&T Bell Laboratories
Finston Martin I.
Jewik Patrick
Ryan Patrick J.
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