Method for manufacturing multilayer circuit board, and multilayer circuit board

Patent metadata

Field	Value
Publication number	US-2017188459-A1
Application number	US-201715442769-A
Country	US
Kind code	A1
Filing date	Feb 27, 2017
Priority date	Aug 29, 2014
Publication date	Jun 29, 2017
Grant date	—

Abstract

A process of manufacturing a multilayer circuit board includes patterning insulating substrates on which conductors are formed to provide a signal conductor, a first ground conductor, and a second ground conductor. The insulating substrates including the signal conductor, the first ground conductor, and the second ground conductor are stacked and thermally crimped to form a laminate. An interlayer connection conductor is formed on a surface of the laminate by a Laser Direct Structuring process.

First claim

What is claimed is:

1 . A method for manufacturing a multilayer circuit board, the method comprising the steps of:
patterning a conductor adhered to an insulating substrate to provide a first conductive pattern; stacking a plurality of insulating substrates, including the insulating substrate on which the first conductive pattern is provided, to form a laminate with at least a portion of the first conductive pattern provided inside the laminate; and providing a second conductive pattern on an outer surface of the laminate; wherein the step of providing the second conductive pattern includes the steps of:
adding a Laser Direct Structuring additive, which includes properties that change upon laser irradiation, to the insulating substrates; and
patterning a surface of a portion to which the Laser Direct Structuring additive is added with laser irradiation, and plating a patterned area with a conductor.

2 . A method for manufacturing a multilayer circuit board, the method comprising the steps of:
providing a first conductive pattern on an insulating substrate; stacking a plurality of insulating substrates, including the insulating substrate on which the first conductive pattern is provided, to form a laminate with at least a portion of the first conductive pattern provided inside the laminate; and providing a second conductive pattern on an outer surface of the laminate; wherein each of the steps of providing the first conductive pattern and the second conductive pattern includes the steps of:
adding a Laser Direct Structuring additive, which includes properties that change upon laser irradiation, to the insulating substrates; and
patterning a surface of a portion to which the Laser Direct Structuring additive is added with laser irradiation, and plating a patterned area with a conductor.

3 . The method for manufacturing a multilayer circuit board according to claim 1 , wherein:
the plurality of insulating substrates include thermoplastic materials; and the step of forming the laminate includes a step of stacking and then thermally crimping the insulating substrates.

4 . The method for manufacturing a multilayer circuit board according to claim 1 , wherein the step of providing the second conductive pattern includes the steps of:
applying the Laser Direct Structuring additive, which includes properties that change upon laser irradiation, to the laminate; and patterning a surface of the laminate on which the Laser Direct Structuring additive is applied with laser irradiation, and plating a patterned area with a conductor.

5 . The method for manufacturing a multilayer circuit board according to claim 1 , wherein
the insulating substrates include an insulating substrate including the Laser Direct Structuring additive, which includes properties that change upon laser irradiation; and the step of providing the second conductive pattern includes a step of patterning a surface of the laminate formed of the insulating substrates including the Laser Direct Structuring additive with laser irradiation, and plating a patterned area with a conductor.

6 . A multilayer circuit board comprising:
a laminate including a plurality of insulating substrates stacked; a first conductive pattern on a main surface of one of the insulating substrates; and
a second conductive pattern on an outer surface of the laminate; wherein
the first conductive pattern is a conductive pattern defined by a patterned conductor adhered to the insulating substrates; and
the second conductive pattern is a conductive pattern defined by a plated material in an area including an irradiated Laser Direct Structuring additive.

7 . The multilayer circuit board according to claim 6 , wherein the first conductive pattern and the second conductive pattern are connected with each other.

8 . A multilayer circuit board comprising:
a laminate including a plurality of insulating substrates stacked; an inner conductive pattern inside the laminate; and
an outer surface conductive pattern on an outer surface of the laminate; wherein
each of the inner conductive pattern and the outer surface conductive pattern is a conductive pattern defined by a plated material at an area including an irradiated Laser Direct Structuring additive.

9 . The multilayer circuit board according to claim 8 , wherein the inner conductive pattern and the outer surface conductive pattern are connected with each other.

10 . The multilayer circuit board according to claim 8 , wherein a portion of the inner conductive pattern is located at a position different from the other portion in a lamination direction of the laminate.

11 . The multilayer circuit board according to claim 6 , wherein
the second conductive pattern is provided on a side surface in a lamination direction of the laminate; and at least one hole is provided in the side surface of the laminate in an area where the second conductive pattern is not located.

12 . The multilayer circuit board according to claim 8 , wherein
the outer surface conductive pattern is located in a side surface in a lamination direction of the laminate; and at least one hole is provided in the side surface of the laminate at an area where the outer surface conductive pattern is not provided.

13 . The multilayer circuit board according to claim 11 , wherein
the at least one hole includes a plurality of holes; and the plurality of holes are located at regular intervals in an extending direction of the laminate.

14 . The multilayer circuit board according to claim 13 , wherein each of the plurality of holes includes a conductive material.

15 . The multilayer circuit board according to claim 6 , wherein the laminate includes:
at least one insulating substrate including a step; and a conductor located on a surface on which the step is provided; wherein the conductor, which is located on the surface including the step, is a conductive pattern defined by the plated material at the area including the irradiated Laser Direct Structuring additive.

16 . The multilayer circuit board according to claim 6 , wherein the first conductive pattern is connected to ground.

17 . The multilayer circuit board according to claim 6 , wherein the first conductive pattern includes:
a first ground conductor located on a first end surface of the laminate in a thickness direction of the laminate; and a second ground conductor located on a second end surface of the laminate in the thickness direction of the laminate.

18 . The multilayer circuit board according to claim 6 , wherein:
at least one first opening is provided in the first ground conductor; at least one second opening is provided in the second ground; at least one external connection terminal is located in the at least one first opening of the first ground conductor; and the at least one second opening of the second ground conductor is a portion of the second ground conductor that overlaps with at least one signal conductor.

19 . The method for manufacturing a multilayer circuit board according to claim 1 , wherein at least one of the plurality of insulating substrates includes an antenna conductor.

20 . The method for manufacturing a multilayer circuit board according to claim 3 , further comprising:
providing at least one hole in the laminate; filling the at least one hole with a conductive paste; and solidifying the conductive paste when the insulating substrates are thermally crimped.

Assignees

• Murata Manufacturing Co

Inventors

• Yosui Kuniaki
• Okamoto Bunta
• Morita Isamu
• Sasaki Jun

Classifications

• H05K2201/09354

  Ground conductor along edge of main surface · CPC title

• H05K3/4632

  laminating thermoplastic or uncured resin sheets comprising printed circuits without added adhesive materials between the sheets · CPC title

• H05K3/4617

  characterized by laminating only or mainly similar single-sided circuit boards · CPC title

• H05K3/403

  Edge contacts; Windows or holes in the substrate having plural connections on the walls thereof (H05K3/4092 takes precedence) · CPC title

• H05K3/182

  characterised by the patterning method · CPC title