Video record disc manufactured by a process involving chemical or sputter etching
AssigneeU.S. Philips Corporation
InventorsBernardus Antonius Johannus Jacobs, Johannes VAN DER Wal, Gerrit Berend Gerritsen
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Abstract
A mother for manufacturing long-playing video records is provided by (1) selectively exposing a photoresist disposed as the outer layer on a substrate comprising a disc-shaped plate, a thin layer of base material, e.g., an oxide of nitride, adhering to the plate and a thin metal layer, e.g., chromium, silver, nickel or titanium, coating the base material layer, (2) removing non-activated sections of the photoresist layer and (3) sputter or chemically etching the thin metal and base material layers in sections corresponding to the removed sections of the photoresist layer.
Claims4
A disc-shaped information carrier comprising a disc-shaped plate and a substantially spiral information-providing track on a surface of said plate produced by subjecting a tightly adhering thin layer of base material disposed on said plate and a thin metal layer coating said base material layer to a sputter etching process to selectively remove portions of the thin metal layer and the underlying base material layer from the surface of said plate.
Dependencies are inferred from the claim text.