Browse Prior Art Database

Producing Very Thin Glass Free Dielectric Layers

IP.com Disclosure Number: IPCOM000109262D
Original Publication Date: 1992-Aug-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 2 page(s) / 86K

Publishing Venue

IBM

Related People

Kaeswurm, G: AUTHOR [+3]

Abstract

The process described in this article does away with prepregs for producing isolating layers and allows depositing glass-free resin layers on existing conventionally produced isolating layers.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 60% of the total text.

Producing Very Thin Glass Free Dielectric Layers

       The process described in this article does away with
prepregs for producing isolating layers and allows depositing
glass-free resin layers on existing conventionally produced isolating
layers.

      During the production of circuit boards, the individual
electric circuit planes are normally isolated from each other by
so-called prepregs which are foils of resin-impregnated glass fiber.

      With ever smaller circuits, finer lines or conductors, smaller
conductor spacings and hole diameters as well as thinner isolating
layers between the circuit layers are indispensable for the
electrical characteristics of the finished board.

      The currently produced isolating layers, using glass fiber
reinforced resins, have a particular minimum thickness of about 0.05
mm as a result of the glass fiber material.

      It is proposed that prepregs, used to produce isolating layers,
be replaced by pure resin which is deposited on the carrier foil in a
preceding step.  The resin-coated foils are applied to the circuit
planes to be isolated, covered with planishing plates, which are
normally used at present, and bonded to each other in a laminating
press, using heat and pressure.

      Then, the planishing plates are removed and the carrier foils
are peeled off.  The resin layer previously existing on the carrier
foil is subsequently completely and uniformly applied to the circuit
plane such that its s...