Method of etching, as well as frame element, mask and prefabricated substrate element for use in such etching
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Dec 2, 2003
Grant Date -
Jul 4, 2002
app pub date -
Sep 18, 2001
filing date -
Sep 18, 2000
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
In a method of etching a substrate having a surface layer of conductive material, a circuit pattern is transferred to the surface layer in a central surface area portion of the substrate by electrochemical etching. To prevent excessive current densities from forming at the periphery of the central surface area portion during the etching step, a frame adapted to attract electrical field is provided adjacent to the central surface area portion. The frame can be part of a separate frame element which is placed on the substrate before the etching step, or be incorporated in a resist coating on the substrate. The frame can be transferred to the resist coating by any suitable means, for example by photolithographic exposure through a mask with a suitable frame pattern. Alternatively, the frame can be incorporated in a prefabricated substrate element, to which the circuit pattern is transferred in the etching step.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully