JP3275502B2 - Method for manufacturing small objects by plating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing minute objects such as a thin film coil and a thin film magnetic layer for a thin film magnetic head by plating means on a substrate.

[0002]

2. Description of the Related Art As plating means, for example, the following means are known. A plate-like anode is disposed at the bottom in the plating tank in which the plating solution is stored, and the substrate is disposed at the top so that the surface to be plated faces downward. An electric current for plating is applied from the anode to the substrate, and a stirring member is repeatedly laterally moved along the lower surface of the substrate under the substrate.

[0003] When plating is performed in this manner, the surface to be plated faces downward, so that high-quality plating can be performed with little adhesion of impurities, and furthermore, the lateral movement of the stirring member causes the central portion and the peripheral portion of the substrate to be repeatedly moved. Can be equalized, so that a wide surface of the substrate can be plated to a uniform thickness.

[0004]

The formation of the thin film coil as an example of the minute object is shown in FIG. 6B by using the entire surface of the substrate 13 as shown in FIG. This is performed by generating a large number of such coils 26. Each coil 26 is mounted on a substrate as shown in FIG.
A seed layer 27 serving as a base for plating is formed on one surface of 13, and a resist pattern 28 is formed thereon, leaving only a portion to be a coil 26 as a recess 29, and a coil is formed on the seed layer 27 in the recess 29. Metal, for example, copper. When such a large number of thin film coils are manufactured by the plating means, a large number of coils 26 can be efficiently manufactured at once. However, the plating thickness of the coil 26 in the central portion of the substrate 13 becomes thicker, and the plating thickness of the coil 26 in the peripheral portion becomes thinner, and a large number of completed coils become products with variations in electrical characteristics. was there.

The present invention has been made to solve the above-mentioned problems (technical problems) of the prior art.
An object of the present invention is to provide a method for manufacturing a minute object in which a large number of minute objects can be efficiently produced therewith utilizing the entire substrate. A second object of the present invention is to provide a method capable of producing a high-quality minute object with less contamination by performing plating with the surface to be plated facing downward. Third
The purpose of this is to arrange the anode in the peripheral part except the central part at the bottom of the plating tank and repeatedly move the stirring member under the substrate, so that the thickness is uniform at both the central part and the peripheral part of the substrate. It is an object of the present invention to provide a method for producing minute objects, which enables plating to be carried out on a plurality of products, so that the electrical characteristics of a large number of products produced efficiently as described above can be made uniform.

[0006]

In order to achieve the above object, the present invention provides a method for producing minute objects by plating, wherein a bottom of a plating tank in which a plating solution is stored is surrounded by an anode except for its center. On the other hand, a substrate on which a large number of resist patterns for forming minute objects are arranged on the lower surface is arranged on the upper surface in the plating tank, and a current is applied for plating from the anode to the substrate, and the substrate is On the lower side, the stirring member is repeatedly moved laterally along the lower surface to generate a large number of minute objects by plating on the lower surface of the substrate.

[0007]

[Function] An anode disposed on the periphery of the bottom of the plating tank except for the central part, a substrate is disposed on the top of the plating tank so that the surface to be plated faces downward, and stirring is performed on the lower side of the substrate. The combination with the repeated lateral movement of the member makes it possible to efficiently produce a large number of minute objects therewith with less contamination of impurities by utilizing the entire substrate, and furthermore, in the central portion of the substrate, The thickness of the generated minute object and the thickness of the minute object generated in the peripheral portion are made uniform.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to 5, reference numeral 1 denotes a plating tank. When the substrate 13 to be plated has a diameter of, for example, 6 inches, the plating tank 1 has, for example, a rectangular shape having a flat internal space of about 7 inches per side. Things are used. Reference numeral 2 denotes a plating solution receiving port, and 3 denotes a plating solution outflow port into the plating tank. A large number of each are disposed on both sides of the upper surface 9a of the anode 9 to form a uniform flow. The plating solution can be drained along. Reference numeral 4 denotes a flow path connecting the receiving port 2 and the outflow port 3. 5 is an overflow port and 6 is a discharge port. Reference numeral 7 denotes a plating solution, and a normal electrolytic solution corresponding to the metal to be plated is used. Reference numeral 8 denotes a receiving member for the anode 9.

The anode 9 is disposed at the bottom of the plating tank 1 at the periphery except the center. For example, anode plate 10
A cover plate 11 made of an insulating material for preventing elution of the anode plate 10 therefrom at the center of the upper surface of the anode plate, for example, a plastic thin plate is polymerized to cover the cover plate, and only the periphery of the anode plate 10 is exposed and 9 functions. Those formed in the shape of a mouth from the beginning may be used. Alternatively, each bar-shaped anode element may be arranged in a square shape. In this case, each anode element may be mechanically arranged apart from each other. The anode 9 is made of copper when copper plating for forming the coil is performed. In the case of forming the magnetic layer of the magnetic head, a magnetic material for the magnetic layer, for example, nickel or a nickel-based alloy is used. The size of the anode 9 is set according to the size of the substrate 13 which is an object to be plated.
The length of one side of the planar shape shown in (1) is a rectangle of the same size as the diameter of the substrate 13, for example, 6 inches. Width W
Is set according to the size of the substrate 13, the density of the portion to be plated on the substrate 13, the size of the anode 9, and other conditions. For example, the coil 26 is mounted on the substrate 13 having a diameter of 6 inches.
In the case of performing copper plating for formation of a hole, the thickness is about 10 mm. The cover plate 11 is detachably attached to the anode plate 10 so that plating can be performed using the entire surface of the anode plate 10.

Reference numeral 12 denotes a holder for holding the substrate 13 in the upper part of the plating tank 1 so that the surface to be plated faces downward. The holder 12 can be inserted into and removed from the plating tank 1 and the substrate 13 can be freely attached and detached. Further, it is configured in a known manner so that the substrate 13 can be fixed while being immersed in the plating solution 7.
The distance between the anode 9 and the substrate 13 is maintained so as to make the flow of the plating solution from the anode 9 side toward the substrate 13 uniform over the entire substrate 13. Substrate
In the case of 13, for example, it is about 7 cm. Reference numeral 14 denotes a stirring member which is provided below the substrate 13 so as to freely move in the horizontal direction along the surface to be plated as indicated by an arrow, and is repeatedly reciprocated by a driving device (not shown). The stirring member 14 is called a paddle. Reference numeral 15 denotes a known DC power supply for plating.

Reference numerals 17 to 24 denote well-known members for circulating the plating solution in the plating tank 1. Reference numeral 17 denotes a reservoir tank, and reference numeral 18 denotes a heating of the plating solution to a normal plating temperature. Heater, 19 is a temperature controller, 20 is a stirrer, 21
Is a circulation pump, and 22 and 23 are filters for removing impurity fine particles, for example, 1 μm and 0.2 μm, respectively.
belongs to. 24 is a flow meter.

When a large number of coils are formed on the substrate 13 as shown in FIG. 6A with the above-described structure, a resist as shown in FIG. A plurality of patterns 28 are provided, the substrate 13 is set as shown in FIGS. 1 and 2, the heater 18, the stirrer 20, the pump 21 and the like are operated, the power is supplied from the power supply 15, and the stirrer 14 is reciprocated ( (For example, 60 reciprocations / minute). The current density of the energization is, for example, the same as in the case of ordinary plating, and is, for example, 0.5 A / dm ² . In this state, the plating solution flowing out of the outlets 3 on both sides in FIG.
After passing through 9a, it joins near the center of the covering member 11, rises from there, and heads toward the substrate 13. The plating solution directed to the substrate 13 is stirred by the stirring member 14 which reciprocates in the horizontal direction.
For this reason, the metal ions for plating are evenly distributed to the concave portions 29 of each resist pattern 28 at the central portion and the peripheral portion of the lower surface of the substrate 13. In this state, the lower surface of the substrate 13 is plated with a predetermined thickness by performing plating for, for example, 30 to 60 minutes. When the plating is completed, the substrate 13 is taken out of the plating bath 1 and the resist pattern 28 is removed as is well known, whereby a number of coils 26 shown in FIG. 6A are completed. When plating was performed under the above-described conditions, the difference in the thickness of the coil 26 between the central portion and the peripheral portion of the substrate 13 could be suppressed to about 3%.

[0013]

As described above, according to the present invention, there is an effect that the first to third objects can be achieved and a large number of fine objects can be manufactured with high quality, high efficiency and high uniformity.

[Brief description of the drawings]

FIG. 1 is a system schematic diagram of a plating apparatus.

FIG. 2 is a partially broken perspective view of a plating tank.

FIG. 3 is a horizontal sectional view of a plating tank.

FIG. 4 is a sectional view taken along line IV-IV in FIG. 3;

FIG. 5 is a sectional view taken along line VV in FIG. 3;

6A is a perspective view of a substrate, FIG. 6B is an enlarged view of a coil, and FIG. 6C is an enlarged sectional view showing a resist pattern.

[Explanation of symbols]

 1 Plating tank 9 Anode 13 Substrate 14 Stirring member

Claims (1)

(57) [Claims] An anode is arranged around a bottom portion of a plating tank in which a plating solution is stored except for a central portion thereof, and a plurality of resist patterns for forming minute objects are formed on a lower surface of an upper portion of the plating tank. Arrange the substrates arranged, and while conducting electricity for plating from the anode to the substrate, on the lower side of the substrate, repeatedly move the stirring member along the lower surface, to the lower surface of the substrate A method for producing minute objects by plating, wherein a large number of minute objects are generated by plating.