WO2000078108A1

WO2000078108A1 - Mounting material, mounting circuit using it and printed wiring board using it

Info

Publication number: WO2000078108A1
Application number: PCT/JP2000/003937
Authority: WO
Inventors: Kinji Saijo; Kazuo Yoshida; Hiroaki Okamoto; Shinji Ohsawa
Original assignee: Toyo Kohan Co., Ltd.
Priority date: 1999-06-16
Filing date: 2000-06-16
Publication date: 2000-12-21
Also published as: AU5249400A; TW495438B

Abstract

A mounting circuit and a printed wiring board, in each of which a composition/size on a circuit is uniform, a position accuracy is good and a solder bump is formed, and a mounting material for forming them, are provided. The mounting material is characterized in that a solder layer (10), a nickel layer (11) and a copper layer (12) are laminated in this order. Further, the mounting material is characterized in that, in its one face, the copper layer (12) having the nickel layer (11) and the solder layer (10) are laminated in order, with the nickel layer (11) being an intermediate layer. Further, in the mounting material, a resin film (20) is laminated on a copper layer (12) side of the mounting material (14).

Description

Description Mounting material, mounting circuit using it, printed wiring board using it

¾ Technical field

The present invention relates to a mounting material for manufacturing a mounting circuit, such as a semiconductor package, on which solder bumps are arranged with high density and high accuracy, a mounting circuit formed using the same, and a printed wiring formed with the mounting material. Regarding the board.

10 Background technology

Conventionally, a solder layer is formed on a part of a wiring layer on a printed wiring board, and this solder layer has been used to mount electronic components such as a semiconductor package. As electronic devices have become smaller and denser in recent years, there has been a demand for narrower pitch solder layers on printed wiring boards and higher positioning accuracy.

^ The typical methods of forming the solder layer are (1) solder coating method (2) solder printing method (3) soldering method, but for (1) and (2) the solder layer size However, there were problems such as large variations in (3) and a large amount of time required for (3). Means for solving the problem of the above method is disclosed in Japanese Patent Application Laid-Open No. 7-66545, and FIGS. 8 and 9 show the manufacturing steps. Prepare the solder foil-clad laminate as shown in Fig. X? Then, the solder foil is etched to form a pattern. Then, as shown in FIG. 9, it is melt-transferred onto the printed wiring board.

However, the above-described method for forming a solder layer still has the following problems to be solved. In other words, after forming a solder pattern by pattern etching, a step of transferring the solder pattern once formed is required, and there has been a problem that the number of manufacturing steps is increased. In addition, when transferring onto a printed wiring board, it was necessary to position with high precision, and with the miniaturization of the circuit, there was a possibility that a problem might occur in the position precision. The present invention is intended to solve the above-described problems, and has a composition-size uniformity on a circuit, a good positional accuracy, a mounting circuit on which solder bumps are formed, a printed wiring board, and the like. An object of the present invention is to provide a mounting material for forming a semiconductor device. Disclosure of the invention

The mounting material of the present invention is characterized in that a solder layer, a nickel layer, and a copper layer are sequentially laminated.

The mounting material according to the present invention is characterized in that a copper layer having a nickel layer and a solder layer are sequentially laminated on one surface with a two-layered nickel layer as an intermediate layer.

The mounting material of the present invention is characterized in that a resin film is laminated on the copper layer side of the mounting material.

In the mounting circuit of the present invention, the solder layer of the mounting material is selectively etched while leaving the copper layer to form a solder bump, and the remaining copper layer is subjected to pattern etching to form a circuit.

) | f.

The printed wiring board of the present invention is characterized in that a mounting material is selectively etched to form a circuit with solder bumps on a resin film.

Mounting material of the present invention, a solder foil in a vacuum chamber, after processing pre-activate the bonding surface of the nickel plating foil or Stevenage gel plated copper-clad resin film, and the solder _foil} the two Ggeru plated Laminate copper foil or copper clad resin film with Nigel

Formed by cold welding at 1-3% of reduction ratio, in which, the activation treatment, in ① 1 X 1 0 '~1 X 1 0- 2 P in extremely low pressure inert gas atmosphere of a (2) The copper foil having the joint surface and the nickel plating are each used as one electrode A grounded to ground, and an AC of 1 to 50 MHz is applied between the electrode A and the other electrode B which is insulated and supported, and the ^ Discharge, ③ and the area of the electrode exposed to the plasma generated by the glow discharge is 1 to 3 times or less of the area of the electrode B. And so on. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic explanatory diagram of a mounting material according to an embodiment of the present invention. FIG. 2 is a process explanatory view of a method for manufacturing a mounting circuit according to an embodiment of the present invention. FIG. 3 is a process explanatory view of a method for manufacturing a mounting circuit according to an embodiment of the present invention. FIG. 4 is a process explanatory view of a method for manufacturing a mounting circuit according to one embodiment of the present invention. FIG. 5 is an explanatory process diagram of a method of manufacturing a mounting circuit according to an embodiment of the present invention. FIG. 6 is a schematic explanatory diagram of a printed wiring board according to one embodiment of the present invention. 7, the onset is an explanatory view of a manufacturing method of mounting material according to the ₀ light of the embodiment. FIG. 8 is an explanatory diagram of a conventional method for manufacturing a printed wiring board. FIG. 9 is an explanatory diagram of a conventional method for manufacturing a printed wiring board. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a method for manufacturing a mounting circuit according to the present invention will be described with reference to the accompanying drawings. First, when a mounting circuit is formed by etching or the like, nickel plating (nickel plating) is applied to one side of a copper foil (copper layer) 12 (preferably 100 to 100 m thick) forming the circuit. 1) (preferably 0.5 to 3 m) to produce a nickel-plated copper foil 13 (see FIG. 1).

Next, the nickel-plated copper foil 13 is wound around a rewind reel 23 in a clad plate manufacturing apparatus as shown in FIG. The solder foil 10 forming the solder bump is wound around the rewind reel 25.

The nickel-plated copper foil 13 and the solder foil 10 are simultaneously rewound from the rewind reels 23, 25, and a part of them is wound around the electrode rolls 27, 28 protruding into the etching chamber 26, and etched. In the chamber 26, a sputter etching process is performed to activate it. In this case, the activation processing, as the applicant has disclosed in JP-1 one 2 2 4 1 8 4 JP above, extremely low pressure of ① 1 X 1 0 '~ 1 X 1 0- 2 P a In an inert gas atmosphere, (2) Nickel-plated copper foil 13 with a bonding surface and solder foil 10 are each grounded to one electrode A, and between electrodes A and B are insulated and supported. Applying an alternating current of 1 MHz to cause a glow discharge, and ③ and the area of the electrode exposed in the plasma generated by the glow discharge is 1/3 or less of the area of the electrode B, and ④ This is performed by performing an etching process.

Then, it is cold-welded by a rolling unit 30 provided in a vacuum chamber 29, wound up on a winding roll 32, and as shown in FIG. 1, for forming a mounting circuit with solder bumps. Manufacture 14

In the above description, an example in which a copper foil (copper layer) that has been previously plated with nickel (nickel layer) is pressure-welded has been described, but instead of nickel plating, the copper foil (copper layer) is formed using the above-described clad plate manufacturing apparatus. A layer in which a nickel foil (nickel layer) is pressed against the layer may be used.

i In the above, a clad material for forming a printed wiring board can be manufactured by using a nickel-plated copper-clad resin film 20 (see FIG. 6) instead of the nickel-plated copper foil. .

In addition, three or more of the above-mentioned rewind reels are installed, and copper foil, copper-foiled resin film, Nigger foil, etc. are installed on these reels, and foil materials are simultaneously supplied from three or more reels. In addition, a clad plate having a multilayer structure can be manufactured by one press welding.

After the above mounting material is cut into a desired size, a mounting circuit is manufactured through the following steps described with reference to FIGS.

First, as shown in FIG. 2, after forming a photoresist film 15 ^ on the surface of the solder foil (solder layer) 10, exposure and development are performed to produce a pattern for forming a solder bump.

As shown in Fig. 3, the selective etching of solder foil 10 and nickel plating 11 was performed. Then, the copper foil 12 is removed leaving the solder bumps 16. As an etchant used for the selective etching, a commercially available solder etchant on copper (for example, Enstrip TL-142 Conc, manufactured by Meltecs Inc.) or the like is preferably used. Next, as shown in FIG. 4, a photoresist film 17 is formed on the circuit-forming copper foil, subjected to iT, and then exposed and developed to form a circuit-forming pattern.

As shown in FIG. 5, the copper foil 12 is etched using ferric chloride or sulfuric acid + hydrogen peroxide. Thus, a circuit 18 is formed. Through the above steps, the mounting circuit 19 can be manufactured.

Also, if the above-described manufacturing process is performed using a material in which a resin sheet is preliminarily laminated on a copper foil as the mounting material shown in FIG. 1, the resin film 20 can be obtained as shown in FIG. A printed wiring board 200 having a circuit on which solder bumps 16 are formed can be manufactured.

The printed wiring board 200 can also be formed by forming the mounting circuit 19 shown in FIG. 5 and then laminating the resin film 20.

Industrial applicability

As described above, in the mounting material according to claims 1 to 3 and 6, since the thickness of each of the solder layer, the nickel layer, and the copper layer is constant, the thickness of the solder bumps is uniform, Even if a semiconductor package is mounted, it does not tilt or no connection failure occurs.

Also, since the solder layer, nickel layer, and copper layer are pressed at a low reduction rate of 0.1 to 3%, the flatness of the joint interface can be maintained by suppressing the stress at the joint interface, and the workability is recovered. No heat treatment is required for this purpose, and no intermetallics are formed at the interface, so that a mounting circuit having excellent selective etching properties can be manufactured using this mounting material.

In the printed wiring board according to claim 5, the mounting material described above is selectively used. Since the circuit with the bump is formed on the resin film by the touching, it can be used as it is as a printed wiring board.

Claims

The scope of the claims

1. A mounting material in which a solder layer, a nickel layer, and a copper layer are sequentially laminated.

2. A mounting material in which a copper layer having a nickel layer on one side and a solder layer are sequentially laminated using the nickel layer as an intermediate layer.

3. A mounting material in which a resin film is laminated on the copper layer side of the mounting material according to claim 1 or 2.

4. Selective etching is performed on the solder layer of the mounting material according to any one of claims 1 to 3 while leaving the copper layer to form a solder bump, and the remaining copper layer is subjected to pattern etching.

, C mounting circuit.

5. A printed wiring board obtained by subjecting the mounting material of claim 3 to selective etching to form a circuit with a solder bump on a resin film.

6. The mounting material is prepared by activating the bonding surface of a solder foil and a nickel-plated copper foil or a nickel-plated copper-clad resin film in a vacuum chamber in advance, and then

,) f The above-mentioned Nigel-coated copper foil or Nigel-coated copper-clad resin film is laminated.

Formed by cold welding at 1-3% of reduction ratio, in which, the activation process, ① 1 X 1 0 '~ 1 X 1 0- 2 in extremely low pressure inert gas atmosphere of P a (2) The copper foil having the joint surface and the nickel plating are each used as one electrode A grounded to ground, and an alternating current of 1 to 50 MHz is applied between the electrode A and the other electrode B which is insulated and supported.

^ Discharge is performed, and ③ and the area of the electrode exposed in the plasma generated by the glow discharge is 1Z3 or less of the area of the electrode B, and ④ sputter etching is performed. 4. The mounting material according to claim 1, wherein: