JPH0290600A - Printed board surface treating device - Google Patents

Abstract

PURPOSE:To prevent a solution from standing on the upside of a substrate so as to improve a pattern in dimensional accuracy by a method wherein spray pressure is made to have such a gradient that it rises up gradually toward an etching treatment center. CONSTITUTION:A piping spray 1 has a U shape that its center 1a is nearer than its ends 1b to a treated piece 2. That is, provided that the distance between the spray piping center 1a and a printed board 2 is equal to 1, the distance between a spray piping end 1b and the printed board 2 is made to be 1.5-3. Nozzles 3 are arranged in such a manner that they are dense at the center 1a and become gradually coarse toward the ends 1b. Five nozzles are arranged at the center 1a and 1-3 nozzles are arranged at the ends 1b respectively. And, the inner diameter of the nozzle 3 is small at the center 1a and becomes gradually larger toward the end 1b. That is, the ratio of the diameter of the nozzle at the center 1a to that of the nozzle at the end 1b is 1:(2-3). Therefore, solution standing on the center of the board 2 is removed by flowing down from the board 2.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printed circuit board surface treatment apparatus, and particularly to a spray piping structure during etching.

(Prior Art) Conventionally, the etching spray piping used in the printed circuit board manufacturing process is linear as shown in FIG. 3, and the nozzles 4a are arranged at equal intervals. Although a related technique is disclosed in Japanese Patent Application Laid-Open No. 61-78123, it does not specifically disclose how to prevent liquid pooling during processing.

(Problem to be Solved by the Invention) In this way, in the past, since the spray piping 4 with nozzles arranged at equal intervals was used, the etching liquid 5 tended to accumulate in the center of the printed circuit board 2, resulting in the etching It was easy to run out. Therefore, as shown in Figure 4,
The formed pattern 7 tended to spread at the base, and the pattern dimensional accuracy could not be improved. Note that 6 is a resist.

An object of the present invention is to eliminate liquid pools on the upper surface of a printed circuit board during etching and to improve pattern dimensional accuracy.

(Means for Solving the Problems) The above object is achieved by increasing the flow velocity at the center of the pipe spray.

As a concrete measure for this purpose, the distance between the center of the spray piping and the substrate is made smaller than the distance between the end of the spray piping and the substrate.

■The nozzle arrangement should be dense in the center and sparse towards the edges.

■ Decrease the diameter of the hole in the center and increase the diameter of the hole at the ends.

These (1) to (2) may be used alone or in combination.

(Function) ■By shortening the distance that the emitted liquid reaches from the center of the piping spray to the substrate, the energy of the liquid is correspondingly large, so the flow rate is also large.

(2) By arranging the nozzles densely in the center and sparsely toward the edges, the liquid becomes fluid when it reaches the center of the substrate and flows toward the edges.

■By making the hole diameter of the spray pipe smaller in the center and larger at the ends, the flow velocity is high from the hole in the center.
At the ends, the flow velocity is reduced.

By using the above three configurations alone or in combination, a liquid pool is less likely to form in the center of the substrate. As a result, insufficient etching can be eliminated and pattern dimensional accuracy can be improved.

(Example) An example of the present invention will be described below with reference to FIG. The piping spray 1 has a U-shape in which the center portion 1a is closer to the object to be treated 2 than the end portions 1b. Specifically, when the distance between the spray piping center 1a and the printed circuit board 2 is "1", the distance between the spray piping end 1b and the printed circuit board 2 is l#
1.5jj~''3 gents.

The nozzle 3 is placed close to the center of the spray pipe 1a.

They are arranged so that they become sparser toward the end 1b.

Specifically, the number of nozzles in the central part 1a is 5, and the number of nozzles in the end part 1
b is the number of nozzles from 1 to 3.

Further, the hole diameter of the nozzle 3 is small at the center portion 1a and becomes large toward the end portion lb. Specifically, the central hole diameter 1
In contrast, the end hole diameter should be at a ratio of 2 to 3.

The above configuration has the effect that the liquid pool at the center of the substrate 2 is eliminated by flowing down from the substrate 2.

(Effects of the Invention) According to the present invention, it is possible to prevent liquid pooling 5 on the upper surface of the substrate during etching, and the formed pattern cross section 7 is
As shown in the figure, since the dimensions match the resist 6, it is possible to improve pattern dimensional accuracy.

By tilting the support base of the printed circuit board 2, the effect of preventing liquid pooling is further enhanced.

[Brief explanation of the drawing]

Fig. 1 is an overview of an embodiment of the present invention, Fig. 2 is a sectional view of a precisely finished conductor pattern, Fig. 3 is an overview of a device using conventional spray piping, and Fig. 4 is a conventional FIG. 3 is a cross-sectional view of a conductor pattern when a liquid pool occurs. 1, U-shaped piping spray 2, printed circuit board 3, nozzle procedure correction form (method) % formula % Relationship with 11 cases of persons correcting printed circuit board surface treatment equipment

Claims (1)

[Claims] 1. 1. A horizontal conveyor type printed circuit board etching apparatus, which is characterized by having a structure in which spray pressure is gradually increased toward a central portion to be etched.