Printed wiring board and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-11382218-B2
Application number	US-201916421547-A
Country	US
Kind code	B2
Filing date	May 24, 2019
Priority date	May 29, 2018
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

In a printed wiring board, when a plurality of wiring base bodies are collectively stacked, a constituent material of a first layer of an insulating resin film has a low melting point, so that the first layer is easily melted. Therefore, thermal welding on an upper surface of the wiring base body is reliably performed, and the wiring base bodies are bonded to each other with high reliability.

First claim

What is claimed is:

1. A printed wiring board comprising:
a plurality of layers of a wiring base body, each of the plurality of layers including:
an insulating resin film having a first main surface that is an uppermost surface of the insulating resin film and a second main surface that is a lowermost surface of the insulating resin film;
a conductive post embedded in the insulating resin film that penetrates the insulating resin film from the first main surface to the second main surface; and
a wiring (1) embedded in the insulating resin film, (2) extending in a direction parallel to the second main surface, and (3) exposed to the second main surface, wherein

the insulating resin film has a multi-layer structure including a first layer with the first main surface and a second layer with the second main surface,
the wiring being embedded in the second layer and not being embedded in the first layer,
the first layer and the second layer are arranged alternately,
a melting point of a constituent material of the first layer is lower than a melting point of a constituent material of the second layer,
the conductive post has a wiring portion exposed to the second main surface and embedded in the second layer and a main body portion extending from the wiring portion to the first main surface through the second layer and the first layer,
the main body portion has a monolithic composition,
the wiring portion and the main body portion of the conductive post are constituted through plating,
the plurality of layers includes a top layer of the plurality of layers and a bottom layer of the plurality of layers,
the first layer and the second layer are alternately throughout the plurality of layers, including the top layer and the bottom layer, and
the wiring and the wiring portion do not extend beyond the second main surface.

2. The printed wiring board according to claim 1 , wherein both the first main surface and the second main surface of the insulating resin film are flat all over the insulating resin film.

3. The printed wiring board according to claim 1 , wherein a cross-sectional shape of the main body portion of the conductive post is even in a thickness direction of the insulating resin film.

Assignees

• Tdk Corp

Inventors

• Morita Takaaki
• Tajima Seiichi
• Kariya Takashi

Classifications

• H05K2201/0141

  Liquid crystal polymer [LCP] · CPC title

• H05K3/4626 Primary

  characterised by the insulating layers or materials (H05K3/4688 takes precedence) · CPC title

• H05K3/4623

  the circuit boards having internal via connections between two or more circuit layers before lamination, e.g. double-sided circuit boards (H05K3/462 takes precedence) · CPC title

• H05K3/4069

  for via connections in organic insulating substrates · CPC title

• H05K3/4655

  by using a laminate characterized by the insulating layer (general-purpose insulating materials H05K1/03, H05K3/4673) · CPC title