Browse Prior Art Database

Process for Producing Lines (conductors) of Equal Width

IP.com Disclosure Number: IPCOM000100003D
Original Publication Date: 1990-Mar-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 1 page(s) / 31K

Publishing Venue

IBM

Related People

Alberth, A: AUTHOR [+4]

Abstract

A process is described for producing lines of equal width on circuit boards.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Process for Producing Lines (conductors) of Equal Width

       A process is described for producing lines of equal width
on circuit boards.

      During circuit board etching, the etch rate is determined by
the exposed and developed structure.  In areas with a great number of
closely adjacent lines, the etch rate is relatively low as a result
of the reduced exchange of etch solution in the narrow channels
between the lines. However, for lines arranged freely, i.e., lines
without adjacent lines, the etch rate is higher, as the etch solution
can be applied to them unimpeded and, once used, be readily removed
from the line edges.  This yields lines with different widths on the
same circuit board.

      By adequate measures in conjunction with the artwork, such etch
rate differences can be eliminated.  During the production of the
artwork, lines arranged freely are defined more widely than closely
adjacent lines.  If the lines are arranged on the circuit board such
that initially there are areas of individual lines followed by denser
areas of closely adjacent lines, the line widths in the artwork are
defined widely or narrowly, according to the respective environment.
Dimensional differences in the line widths are determined empirically
by etch rate tests prior to producing the artwork.