Nitto-denko Corporation

Daisuke Yamauchi

Hiroyuki Tanabe

Mitsuru Honjo

Yuu Sugimoto

Naohiro Terada

Tetsuya Oosawa

Tetsuya Ohsawa

Jun Ishii

Hitoki Kanagawa

Masami Inoue

Kei Nakamura

Naotaka Higuchi

Tadao Ookawa

Takatoshi Sakakura

In a suspension board, a ground layer and a first insulating layer are formed on a support substrate. The ground layer has electric conductivity higher than that of the support substrate. A power wiring trace is formed on the first insulating layer. A second insulating layer is formed on the support substrate to cover the ground layer and the first insulating layer. A write wiring trace is formed on the second insulating layer to at least partially overlap with the ground layer. A distance between the ground layer and the write wiring trace in a stacking direction of the support substrate, the first insulating layer and the second insulating layer is set larger than a distance between the power wiring trace and the write wiring trace in the stacking direction.

Printed circuit board and method of manufacturing the same

In a suspension board, a first insulating layer is formed on a support substrate. A ground layer and a power wiring trace are formed on the first insulating layer. The ground layer has electric conductivity higher than that of the support substrate. A second insulating layer is formed on the first insulating layer to cover the ground layer and the power wiring trace. A write wiring trace is formed on the second insulating layer to overlap with the ground layer. In a stacking direction of the support substrate, the first insulating layer and the second insulating layer, a distance between the ground layer and the write wiring trace is larger than a distance between the power wiring trace and the write wiring trace.

A method of producing a suspension board with circuit includes the steps of preparing a metal supporting layer, forming a curable insulating layer on the metal supporting layer using a photosensitive curable insulating composition such that an opening is formed in the curable insulating layer, curing the curable insulating layer to form an insulating layer, subjecting the metal supporting layer exposed from the opening to microwave plasma treatment, and forming a metal conducting portion on the metal supporting layer exposed from the opening.

Method of producing suspension board with circuit

A first insulating layer is formed on a support substrate. The first insulating layer includes a first portion and a second portion. The second portion has a thickness smaller than that of the first portion. A ground layer having electric conductivity higher than that of the support substrate is formed on the second portion of the first insulating layer. The ground layer is electrically connected to the support substrate. A second insulating layer is formed on the first insulating layer to cover the ground layer. A write wiring trace is formed on the second insulating layer to overlap with the first portion and the second portion of the first insulating layer.

A wired circuit board includes an insulating layer and a plurality of wires disposed at one-side surface in a thickness direction of the insulating layer at spaced intervals to each other. The plurality of wires have one pair of wires in parallel, the plurality of wires continuously have a first portion and a second portion in which the total sum of a line width of one wire of one pair of wires and an interval between one pair of wires is smaller than that of the first portion, and a thickness Tof the first portion is large with respect to a thickness Tof the second portion.

Wired circuit board

A suspension board with circuit includes a metal supporting board, a base insulating layer disposed at one side in a thickness direction of the metal supporting board, and a conductor layer disposed at one side in the thickness direction of the base insulating layer and including a connecting terminal electrically connected to a slider. The base insulating layer has a terminal region, when projected in the thickness direction, overlapped with at least the connecting terminal and a circumferential region not overlapped with the terminal region and around the terminal region, and the thickness of the terminal region is thicker than that of the circumferential region.

Suspension board with circuit and producing method thereof

A wired circuit board includes an insulating layer and a conductive layer. The insulating layer continuously has a first insulating portion, a second insulating portion having a thickness smaller than that of the first insulating portion, and a third insulating portion disposed between the first insulating portion and the second insulating portion and having a thickness that gradually becomes smaller from the first insulating portion toward the second insulating portion. The conductive layer continuously has a first conductive portion disposed at one-side surface of the first insulating portion and a second conductive portion disposed at one-side surface of the second insulating portion and having a thickness smaller than that of the first conductive portion. The first conductive portion is disposed at one-side surface of the second insulating portion and the third insulating portion or is disposed at one-side surface of the first insulating portion and the third insulating portion.

Wired circuit board and producing method thereof

A printed circuit board includes first and second insulating layers, a wiring trace, a metal thin film, and a connection terminal. The wiring trace is formed on the first insulating layer. The metal thin film is formed on the wiring trace, and has a thickness larger than 0 nm and not more than 150 nm. The second insulating layer is formed on the first insulating layer to cover the metal thin film. The connection terminal is formed on the first insulating layer to be electrically connected to the wiring trace and exposed from the second insulating layer.

Printed circuit board having reduced loss of electric signal and method of manufacturing the same

A suspension board with circuit includes a metal supporting board, a base insulating layer disposed at one side in a thickness direction of the metal supporting board, a conductor layer disposed at the one side of the base insulating layer and including a connecting terminal electrically connected to a slider, a cover insulating layer covering the conductor layer to expose the connecting terminal and disposed at the one side of the base insulating layer, and a plating layer covering the connecting terminal. The cover insulating layer includes a first cover insulating layer disposed at the one side of the base insulating layer and a second cover insulating layer disposed at the one side of the first cover insulating layer, and the thickness of the plating layer is not more than the total sum of the thickness of the first cover insulating layer and that of the second cover insulating layer.

A conductor trace is formed on a base insulating layer. The conductor trace includes two terminal portions and one wiring portion. The wiring portion is formed to connect the two terminal portions to each other and extend from each terminal portion. A metal cover layer is formed to cover the terminal portion and the wiring portion of the conductor trace and continuously extend from a surface of the terminal portion to a surface of the wiring portion. The metal cover layer is made of metal having magnetism lower than magnetism of nickel, and is made of gold, for example. A cover insulating layer is formed on the base insulating layer to cover a portion, of the metal cover layer formed on the conductor trace, covering the wiring portion and not to cover a portion of the metal cover layer covering the terminal portion.

A base insulating layer is formed on a suspension body. Read wiring patterns, write wiring patterns and a ground pattern are formed in parallel on the base insulating layer. A first cover insulating layer is formed on the base insulating layer to cover the read wiring patterns, the write wiring patterns and the ground pattern. A ground layer is formed in a region on the first cover insulating layer above the write wiring patterns. A second cover insulating layer is formed on the first cover insulating layer to cover the ground layer.

A cover insulating layer is formed on a base insulating layer. One of write wiring traces includes first to third lines, and the other write wiring trace includes fourth to sixth lines. The one and other write wiring traces constitute a signal line pair, the second and fifth lines are arranged on an upper surface of the cover insulating layer, and the third and sixth lines are arranged on an upper surface of the base insulating layer. At least parts of the second and fifth lines are respectively opposed to the sixth and third lines with the cover insulating layer sandwiched therebetween. The second and third lines are electrically connected to the first line, and the fifth and sixth lines are electrically connected to the fourth line. The fourth line is electrically connected to at least one of the fifth and sixth lines through a jumper wiring on a lower surface of the base insulating layer.

A base insulating layer is formed on a suspension body. A lead wire for plating and a wiring trace are integrally formed on the base insulating layer. A cover insulating layer is formed on the base insulating layer to cover the lead wire for plating and the wiring trace. A thickness of a portion of the cover insulating layer above a region of the base insulating layer in which the lead wire for plating is formed is set smaller than the thickness of a portion of the cover insulating layer above other regions of the base insulating layer.

An insulating layer is formed on a support substrate having a conductive property. Write wiring traces, read wiring traces, and first and second electrode pad pairs are formed on the insulating layer. The first electrode pad pair is connected to the write wiring traces. The second electrode pad pair is connected to the read wiring traces. Parts of regions of the support substrate, which overlap the electrode pads, are removed. Thus, openings are formed in the regions of the support substrate, which overlap the electrode pads.

Two transmission lines are formed adjacent to each other at spacing on an upper surface of a base insulating layer, and a ground conductor layer is formed on a lower surface of the base insulating layer. The ground conductor layer is arranged to be opposite to at least part of one transmission line and at least part of the other transmission line in a width direction of the two transmission lines. When a width of one transmission line, a width of the other transmission line, a spacing between the two transmission lines and a width of the ground conductor layer in an arbitrary cross section perpendicular to the two transmission lines are referred to as W1, W2, S, Wg, respectively, the width Wg of the ground conductor layer is set to satisfy relationship of Wg&#x3c;(W1+W2+S) and S&#x2266;0.8 Wg.

Growing community of inventors

Ibaraki, Japan

Daisuke Yamauchi