JP2000328267A - Etching device and production of printed circuit board using the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an etching device for producing printed circuit boards with the lessened unevenness of an etching quantity and the decreased variations in circuit widths and also provide a process for producing the printed circuit boards by using the device. SOLUTION: This etching device having a spray atomizing nozzle for plural chemical etchants further has an air or inert gas discharging nozzle. A process for producing the printed circuit boards consists in atomizing the chemical etchants from the spray atomizing nozzle for the plural chemical etchants and blowing the air or the inert gas from the air or inert gas discharging nozzle when etching the unnecessary conductors of substrates to constitute the printed circuit boards.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an etching apparatus and a method for manufacturing a printed wiring board using the etching apparatus.

[0002]

2. Description of the Related Art Generally, an etching apparatus used for processing a circuit of a printed wiring board has an outer diameter of 20 to 50 for conveyance.
mm conductors are horizontally arranged, and a chemical etching solution is sprayed from above and below at the same time as the transfer, thereby removing unnecessary conductors by etching. At this time, the rim of the annular roll is opened through a window so that the etching solution is evenly sprayed on the substrate, and a slit is provided in the tire of the annular roll so as to minimize the area of contact with the substrate as much as possible. However, the substrate to be a printed wiring board is usually a thin plate, and the substrate is deflected by the weight of the etching solution, the etching solution accumulates on the upper surface, and the chemical reaction between the metal to be etched and the etching solution becomes insufficient. Inconsistencies such as unevenness in the amount and variations in the circuit width formed by the unevenness occur. As a solution to this problem, usually, a method is employed in which a rod-shaped roll having an outer diameter of 30 to 40 mm is partially used in addition to the ring-shaped roll, and the etching liquid is removed so as to be flushed away to prevent accumulation. Further, as another similar method, a method of arranging a plurality of movable plates in contact with the substrate on the upper surface of the substrate and removing the etchant by scraping it off to prevent accumulation is also adopted. Further, as equipment for preventing the accumulation of etching liquid, an etching apparatus for vertically transporting a substrate has been proposed.

[0003]

However, among the conventional techniques, in the method of flushing out the etching solution with a rod-shaped roll, if a ring-shaped roll is used below the rod-shaped roll, the rod-shaped roll only comes into contact with the ring-shaped roll from below. In many cases, the roll comes into contact with the etching resist on the surface of the substrate, causing a problem in that the etching resist is damaged, and a defect such as disconnection occurs in the circuit of the workpiece. In addition, since the upper and lower rolls are in contact with the entire surface, the scratches on the etching resist are reduced, but the chemical etching solution cannot be sprayed uniformly unless the distance between the transport rolls is widened, but the thin plate-shaped substrate tends to bend. Since it is coated with an etching solution, it is easy to bend so as to wind around either of the upper and lower rolls. In the method of arranging a plurality of movable plates in contact with the workpiece on the upper surface of the substrate, the etching resist in contact with the edge of the plate is easily scratched, and defects such as disconnection occur in the circuit of the substrate. There is a problem that. Further, in an etching apparatus for vertically transporting a substrate, there is a problem that the equipment is complicated and expensive, the substrate needs to be mounted on a dedicated jig, and the productivity is low and the method is not practical.

According to the present invention, the unevenness of the etching amount is small,
An object of the present invention is to provide an etching apparatus for manufacturing a printed wiring board having a small circuit width variation and a method for manufacturing a printed wiring board using the etching apparatus.

[0005]

According to the present invention, there is provided an etching apparatus having a plurality of spray nozzles for chemical etching liquid, further comprising a nozzle for discharging air or an inert gas.

Further, according to the method of manufacturing a printed wiring board of the present invention, when etching unnecessary conductors of a substrate to be a printed wiring board, a chemical etching liquid is sprayed from a plurality of spray nozzles for a chemical etching liquid. It is characterized in that air or inert gas is blown from a nozzle for discharging air or inert gas.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The nozzle for discharging air or an inert gas to be blown onto a substrate can be used in any spray shape, but preferably blows gas in a straight line perpendicular to the direction of substrate movement. Nozzles are preferred,
Further, a nozzle that sprays a gas in a spray shape that is perpendicular to the direction of travel of the substrate and that is bent in the shape of a square at the center is more preferable. The gas discharge pressure is 0.1 MPa
To 0.3 MPa, more preferably 0.15
MPa to 0.25 MPa. If the discharge pressure of this gas is less than 0.1 MPa, the force for removing the etchant is weak, and if it exceeds 0.3 MPa, the etchant may be blown off, resulting in uneven etching.

In these nozzles, a plurality of air or inert gas discharge nozzles can be provided in a line in a line perpendicular to the transport direction of the printed wiring board between a plurality of spray nozzles for chemical etching liquid. .

Further, a plurality of spraying nozzles for chemical etching liquid are provided at a "-"-shaped position with the apex substantially at the center of the width of the conveying path in the conveying direction of the printed wiring board. Provision of such an arrangement is preferable because the etching solution can be removed more efficiently.

[0010]

Example 1 A photosensitive film was laminated on a double-sided copper-clad laminate in which electrolytic copper foil having a thickness of 35 μm was adhered to both sides, and then a photomask having a pattern having a circuit width of 100 μm and a circuit interval of 100 μm was overlaid. Exposure to UV light and development
As shown in (a), an etching apparatus is used in which a plurality of gas discharge nozzles are mounted in a line in a line perpendicular to the direction of transport of a printed wiring board between a plurality of chemical etching solution spray spray nozzles. Air is blown at a pressure of 0.2 MPa, and the etching solution contains 1 mol / l hydrochloric acid.
A circuit was formed by etching an aqueous solution of ferric chloride at 0 ° C. and a specific gravity of 1.32 at a spray pressure of 0.15 MPa for 80 seconds.

Example 2 As shown in FIG. 1 (b), between a plurality of spray nozzles for a chemical etching solution, the center of the width of the transport path is set to the apex in the transport direction of the printed wiring board. A circuit was formed by etching in the same manner as in Example 1 using an etching apparatus provided with a plurality of gas discharge nozzles at the positions of the "<".

Comparative Example A circuit was formed in Example 1 without using a gas discharge nozzle.

The circuit widths formed in the examples and comparative examples were measured. Table 1 shows the results.

[0014]

[Table 1] As can be seen from this table, the circuit width of the circuit etched by the method of the present invention had little variation.

[0015]

As described above, according to the present invention,
An etching apparatus for manufacturing a printed wiring board having a small variation in circuit width and a method for manufacturing a printed wiring board using the etching apparatus can be provided.

[Brief description of the drawings]

FIG. 1A is a perspective view for explaining one embodiment of the present invention, and FIG. 1B is a perspective view showing another embodiment of the present invention.

Claims (4)

[Claims] 1. An etching apparatus having a plurality of spray nozzles for chemical etching liquid, further comprising a nozzle for discharging air or an inert gas. 2. A method according to claim 1, wherein a plurality of air or inert gas discharge nozzles are provided between the plurality of chemical etching liquid spray nozzles in a line perpendicular to the direction of transport of the printed wiring board. The etching apparatus according to claim 1. 3. A plurality of spraying nozzles for chemical etching liquid, each having a plurality of "C" -shaped positions with the apex substantially at the center of the width of the conveying path in the conveying direction of the printed wiring board. The etching apparatus according to claim 1, wherein the etching apparatus is provided. 4. When etching unnecessary conductors on a substrate to be a printed wiring board, a chemical etching liquid is sprayed from a plurality of chemical etching liquid spray spray nozzles, and air or an inert gas discharging nozzle is sprayed with air or inert gas. A method for manufacturing a printed wiring board, characterized by blowing an inert gas.