Mitsui Minings & Melting Co., Ltd.

Hiroaki Kurihara

Takeshi Iwase

Yoshinori Matsuura

Makoto Dobashi

Naotomi Takahashi

Hiroshi Hata

Toshiko Yokota

Joe Nishikawa

Tatsuya Sudo

A measurement method capable of acquiring, in a simple manner, a surface parameter of copper foil exhibiting high correlation with high frequency characteristics, the method including: (a) acquiring a surface profile of surface-treated copper foil as a reference; (b) setting a cutoff value for an L filter, the cutoff value satisfies: (i) an arithmetical mean height Sa after processing with the L filter, being 0.5 μm or less, and (ii) a percent change of Sdr or α value after processing with the L filter being 80% or less; (c) acquiring a surface profile of surface-treated copper foil as a measurement object; (d) subjecting the acquired surface profile of the copper foil as the measurement object to filter processing; and (e) calculating at least one of surface parameters defined in ISO25178 on the copper foil as the measurement object based on the surface profile after the filter processing.

Method for measuring surface parameter of copper foil, and method for sorting copper foil

A method for measuring a surface parameter of copper foil exhibiting high correlation with high frequency characteristics, the method for measuring a surface parameter of copper foil including: (a) acquiring a surface profile on at least one surface of an untreated copper foil; (b) setting a cutoff value for an L filter based on the surface profile; (c) acquiring a surface profile on at least one surface of surface-treated copper foil originating from the untreated copper foil; (d) subjecting the surface profile of the surface-treated copper foil to filter processing, the filter processing including processing using an L filter with the cutoff value; and (e) calculating at least one of surface parameters defined by ISO25178 on the surface of the surface-treated copper foil based on the surface profile after the filter processing.

Method for measuring surface parameter of copper foil, method for sorting copper foil, and method for producing surface-treated copper foil

There is provided a surface-treated copper foil including a surface coating layer provided on at least one surface of a copper foil, the surface coating layer being mainly composed of silicon with a hydrogen content of 1 to 35 atomic % and/or a carbon content of 1 to 15 atomic %. This foil can be manufactured by forming a surface coating layer composed mainly of silicon with the above hydrogen and carbon contents on at least one surface of the copper foil by PVD or CVD. The present invention can provide a copper foil with a surface coating layer that can achieve a high bonding strength to a resin layer even if the copper foil has an extremely smooth surface such as one formed by vapor deposition, for example, sputtering and also has a desirable insulation resistance suitable for achieving a fine pitch in a printed wiring board.

Surface-treated copper foil, method for producing same, copper-clad laminate for printed wiring board, and printed wiring board

A printed wiring board group includes a plurality of printed wiring boards wherein a difference (&#x394;&#x3a9;&#x2212;AB) between an average electric resistance (A-ave.) of wires formed in one printed wiring board (A) and an average electric resistance (B-ave.) of wires formed in a printed wiring board (B) adjacent to the printed wiring board (A) is within a range of &#xb1;5% of an average electric resistance (AB-ave.) of the wires of the printed wiring boards (A) and (B); and a difference (&#x394;&#x3a9;&#x2212;ab) between an electric resistance (a-) of an outermost wire of the printed wiring board (A) and an electric resistance (b-) of an outermost wire of the printed wiring board (B) is within a range of &#xb1;11.05%, preferably within a range of &#xb1;6.12%, and is particularly preferably within a range of &#xb1;6.00% of the average electric resistance (AB-ave.) of the printed wiring boards (A) and (B).

Printed wiring board

Disclosed is a flexible wiring substrate which does not form anomalous deposition of tin-bismuth alloy plating, through prevention of exfoliation, during the process of plating with tin-bismuth alloy, of a solder resist layer. A method for producing the flexible wiring substrate is also disclosed.

Flexible wiring substrate and method for producing the same

The present invention provides a flexible wiring substrate which does not form anomalous deposition of tin-bismuth alloy plating, through prevention of exfoliation, during the process of plating with tin-bismuth alloy, of a solder resist layer. The invention also provides a method for producing the flexible wiring substrate. The flexible wiring substrateincludes an insulating substrate, a wiring patternformed on a surface of the insulating substrate, and a solder resist layercovering a surface of the wiring patternexcluding at least terminal portions of the wiring pattern, at least a portion of the outermost surface of the wiring patternwhich is not covered with the solder resist layerbeing provided with a tin-bismuth alloy plating layer, characterized in that the wiring patterncomprises a base layerformed of a conductor and that a first tin plating layeris provided on the base layerso as to extend under a region covered with the solder resist layerand also under a region not covered with the solder resist layer

Flexible wiring base material and process for producing the same

A copper foil having improved resistance to abrasion damage during the manufacture of printed circuit boards has a uniform deposit of benzotriazole (BTA) or BTA derivative, optionally a mixture thereof, of at least about 5 mg/m,.

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Shimonoseki, Japan

Hiroaki Kurihara