Multilayer wiring board and its manufacturing method
AssigneePanasonic Corporation
InventorsTadashi Nakamura, Fumio Echigo, Shogo Hirai
Life of this patent
Estimating the term…
Abstract
A multilayer wiring board employs a thin insulating substrate having substantially only resin flow as the compression property effect, and has an any-layer IVH structure where at least one core layer is formed without burying wiring. For sufficiently securing an effective compression amount of the crush-allowance of a conductor, the ratio of the thickness of a cover film to that of the electrical insulating substrate is increased, and a via can be formed in the core layer without burying the wiring in the insulating substrate. Thus, a multilayer wiring board having an any-layer IVH structure that can achieve high-density component mountability and wiring storability in an extremely small thickness can be provided.
Claims18
A multilayer wiring board having an any-layer IVH structure, the multilayer wiring board comprising:
- an insulating substrate having a via hole;
- conductive paste disposed in the via hole;
- and
- wiring layers coupled to each other with the conductive paste,
- wherein the wiring layers are not buried in the insulating substrate,
- wherein the insulating substrate has a thickness smaller than 40 μm,
- wherein substrate compressibility of the insulating substrate in a thickness direction is lower than 5%,
- wherein the conductive paste is disposed in the via hole of the insulating substrate by applying cover films to opposing surfaces of the insulating substrate, forming the via hole in the insulating substrate and the cover films, filling the via hole with the conductive paste, and then removing the cover films such that the conductive paste projects from each surface of the insulating substrate by a height equal to a thickness of the cover film removed from the surface, and
- wherein the height of the conductive paste is 25% or larger of the thickness of the insulating substrate.
A multilayer wiring board having an any-layer IVH structure, the multilayer wiring board comprising:
- an insulating substrate having a via hole;
- conductive paste disposed in the via hole;
- and
- wiring layers coupled to each other with the conductive paste,
- wherein the wiring layers are not buried in the insulating substrate,
- wherein the insulating substrate has a thickness smaller than 40 μm,
- wherein substrate compressibility of the insulating substrate in a thickness direction is lower than 5%,
- wherein the conductive paste is disposed in the via hole of the insulating substrate by applying cover films to opposing surfaces of the insulating substrate, forming the via hole in the insulating substrate and the cover films, filling the via hole with the conductive paste, and then removing the cover films such that the conductive paste projects from each surface of the insulating substrate by a height equal to a thickness of the cover film removed from the surface, and
- wherein the height of the conductive paste is 20% or smaller of a diameter of the via hole.
A multilayer wiring board having an any-layer IVH structure, the multilayer wiring board comprising:
- an insulating substrate having a via hole;
- conductive paste disposed in the via hole;
- and
- wiring layers coupled to each other with the conductive paste,
- wherein the wiring layers are not buried in the insulating substrate,
- wherein the insulating substrate has a thickness smaller than 40 μm,
- wherein substrate compressibility of the insulating substrate in a thickness direction is lower than 5%,
- wherein the conductive paste is disposed in the via hole of the insulating substrate by applying cover films to opposing surfaces of the insulating substrate, forming the via hole in the insulating substrate and the cover films, filling the via hole with the conductive paste, and then removing the cover films such that the conductive paste projects from each surface of the insulating substrate by a height equal to a thickness of the cover film removed from the surface, and
- wherein the height by which the conductive paste projects from each surface of the insulating substrate is 20% or smaller of a diameter of the via hole.
Dependencies are inferred from the claim text.