JPS6235912B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Application) The present invention relates to a screen printing device, and in particular, to a screen printing device that can easily and precisely align a printing screen with respect to a substrate to be printed. It is related to the device.

(Prior Art) As is well known, in the manufacture of thick film hybrid ICs, a method of forming patterns of conductors, dielectrics, resistors, etc. in one layer or multiple layers by screen printing is often employed. ing.

In this case, as devices become smaller,
The alignment between each pattern and between each layer, and therefore the alignment of a printing screen with respect to a substrate to be printed, increasingly requires high precision.

At present, the alignment of the printing screen with respect to the substrate to be printed is performed visually by an operator.

However, as the patterns on the printing screen become finer, alignment within acceptable tolerances becomes virtually impossible, and after several prints with one printing screen, the pattern on the substrate through the screen apertures becomes virtually impossible to align. The extreme difficulty in seeing the pattern again makes alignment with sufficient accuracy impossible.

Therefore, not only does it take a long time and skill to align the printing screen to the substrate to be printed, and there are large individual differences, but in practice, it is difficult to determine the required accuracy unless you actually make a test print. The disadvantage was that it was not possible to align the position. Additionally, this has the disadvantage that work efficiency tends to decrease.

(Objective) The present invention has been made in order to eliminate the above-mentioned drawbacks, and its object is to easily and accurately align a printing screen to a printed substrate with high precision without relying on visual inspection. The objective is to provide a screen printing device that can

(Summary) In order to achieve the above object, the present invention provides a pair of alignment electrodes insulated from each other at a predetermined position of a printed substrate placed at a predetermined position on a stage during screen printing. , when the printing screen is aligned with sufficient accuracy with respect to the substrate to be printed, a pair of alignment conductors conductively connected to each other are placed on the printing screen opposite to the alignment electrodes. Provide a protrusion,
The present invention is characterized in that it is configured to determine whether or not the alignment of the printing screen with respect to the substrate to be printed is completed by detecting the conduction state between the pair of alignment electrodes.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view showing a state in which a substrate to be printed is placed at a prescribed position on a stage in an embodiment of the present invention.

As is clear from the figure, positioning pins 2, 3, and 4 are installed on the stage 9. By placing the printed substrate 1 on the stage 9 and bringing its two sides into contact with the alignment pins 2, 3, and 4, the printed substrate 1 on the stage 9 is placed.
The alignment is done correctly.

At the periphery of the printed substrate 1 outside the printing area,
A pair of external electrode pads 2L and 3L are provided. Alignment electrodes 2P and 3P are formed on the external extraction electrode pads 2L and 3L, respectively.

Further, lead wires 2A, 3A are connected to the alignment electrode pads 2L, 3L, respectively, and the alignment electrodes 2P, 3A are connected between these lead wires.
Means for detecting the conduction state between 3Ps (in this example,
A series circuit of a power supply E, a protection resistor R, and an ammeter M is connected.

FIG. 2 is a bottom view of the printing screen in the embodiment of the present invention. A support frame 10 having sufficient mechanical strength is provided around the printing screen 8, and a desired printing pattern (or opening) 12 is bored in a portion of the printing screen 8.

A rectangular area indicated by a two-dot chain line 15 corresponds to the printed substrate 1 in FIG. 1, and the printed pattern 12 is formed within this area.

Further, conductive projections 6 and 7 for alignment are formed downward at positions corresponding to the alignment electrodes 2P and 3P in FIG. 1 on the printing screen 8.

In this example, it is assumed that the printing screen 8 is a metal screen made of a metal thin film, so that the alignment conductive protrusions 6 and 7 and the printing screen 8 are electrically connected.

As will be described in detail later, when the printing screen 8 is correctly placed at the regular position, the tips of the alignment conductive protrusions 6 and 7 touch the alignment electrodes 2.
P, 3P, thereby aligning the printing screen 8 with respect to the printed substrate 1, the alignment conductive protrusions 6,
It is desirable that the cross-sectional area of the tip 7 be made as small as possible.

FIG. 3 is a schematic configuration diagram for explaining the operation when aligning the printing screen with respect to the substrate to be printed according to the present invention. In this figure, the same reference numerals as in FIGS. 1 and 2 represent the same or equivalent parts.

As described above, the two positioning conductive protrusions 6 and 7 are electrically connected to each other. Therefore, as is clear, in FIG. 3, when the alignment electrode 2P and the alignment conductive protrusion 6 are in contact with each other, and the alignment electrode 3P and the alignment conductive protrusion 7 are in contact with each other, Only then, the circuit of the power source E is closed and current flows through the ammeter M.

Therefore, by detecting this current and driving a notification means (by sound, light, etc.) based on the result, it is possible to indicate the completion of alignment.

Furthermore, if the current detection signal is used to prevent the relative movement of the printed substrate 1 or the stage 9 and the printing screen 8 and to fix them, the labor of the operator can be saved. Accurate alignment can be performed semi-automatically.

Further, a guide capable of accurately positioning one side of the printing screen 8 is provided, for example, on the stage 9, and the printing screen 8 is configured to automatically slide along this guide. If the sliding of the printing screen 8 is stopped and fixed based on the detection signal, it is possible to automate the alignment.

In the present invention, the positioning conductive protrusions 6 and 7 provided on the printing screen 8 and the printed substrate 1
The positions of the alignment electrodes 2P and 3P provided above are
If the positioning pins 2 to 4 are set in a peripheral area sufficiently away from the printing area on the printed substrate 1, and the height of the alignment pins 2 to 4 is selected to be lower than the thickness of the printed substrate 1,
The printing operation by the printing screen 8 is no longer affected.

The present invention can be modified and implemented as follows.

(1) Instead of the conductive projections 6 and 7 for positioning, use springs, needle-like contacts, or cut and raised pieces.

(2) A mesh screen is used as the printing screen 8. In this case, it is necessary to connect the positioning conductive projections 6 and 7 with a suitable conductive material (for example, a conductive support frame).

(Effects) As is clear from the above description, according to the present invention, the following effects are achieved.

(1) Since the alignment of the printing screen with respect to the substrate to be printed is determined mechanically, alignment work is simplified and streamlined. At the same time, individual differences and variations in alignment accuracy are eliminated, resulting in uniform screen printing.

(2) It also becomes possible to automate or semi-automate the alignment of the printing screen to the substrate to be printed.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a printed substrate placed at a prescribed position on a stage, FIG. 2 is a bottom view of a printing screen according to an embodiment of the present invention, and FIG. FIG. 2 is a schematic configuration diagram for explanation. 1... Printed substrate, 2, 3, 4... Aligning pin, 2P, 3P... Aligning electrode, 6, 7...
Conductive projections for positioning, 8...screen for printing,
9... Stage, 10... Support frame, 12... Print pattern.

Claims (1)

[Scope of Claims] 1. a stage; a pair of alignment electrodes fixed to predetermined positions on a printed substrate placed on the stage and electrically insulated from each other; means for detecting conduction between the alignment electrodes; and a means for contacting each of the alignment electrodes when a pattern to be printed is formed and correctly aligned with the printed substrate. 1. A screen printing apparatus comprising: a printing screen provided with a pair of positioning conductive protrusions electrically connected to each other in such a position; 2. Claim 1, wherein the printing screen is a metal screen.
Screen printing device as described in Section. 3. The screen printing apparatus according to claim 1, wherein the printing screen is a mesh screen. 4. The screen printing apparatus according to claim 1, wherein the stage is provided with a guide for positioning one side of the printing screen.