JPH012392A - Conductor pattern formation method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method of forming conductive patterns for mounting various electronic components on an insulating circuit board.

<Prior Art> A printed wiring board is an example of an insulating circuit board on which conductor patterns are formed for mounting various electronic components.

In the production of conventional printed wiring boards, a screen or mask is first created based on a design drawing, and a conductive pattern is formed on the circuit board by screen printing using the screen or etching using the mask. There is.

<Problems to be Solved by the Invention> Such conventional methods of forming conductor patterns have various advantages such as uniform quality of the product and the possibility of reducing the size and weight of the product. Because it is necessary to create originals for screens, masks, etc. each time, it is difficult to respond to design changes, and there is a problem in that high-mix, low-volume production increases costs.

The present invention has been made in view of the above-mentioned problems, and is capable of forming a conductive pattern on a circuit board in direct conjunction with a control device such as a computer that processes data regarding the conductive pattern. The purpose is to make it easier to respond to design changes, eliminate the need to create originals such as screens and masks, and enable production of multiple types of small and medium-sized bonds without increasing costs.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention provides a transfer film formed by applying a conductive paste on a base film, and transfers it to a circuit board on which a conductive pattern is to be formed. A transfer head having a heat generating part is applied to the surface of the circuit board through the transfer film, and the transfer head is moved relative to the circuit board, and in connection with this movement, the transfer head is supplied with the necessary electricity corresponding to the conductor pattern. The conductive paste of the transfer film was transferred onto the circuit board by inputting a signal and generating heat from the heat generating part of the transfer head.

In the above method, data regarding the conductive pattern to be formed is stored in a storage unit of a control device such as a computer, and the control device responds to the data in relation to the relative movement between the circuit board and the transfer head. When an electric signal is input to the transfer head, the conductor paste is transferred onto the circuit board one after another by the heat generated by the heat generating part of the transfer head, and the conductor paste adheres to the circuit board according to the shape of the conductor pattern. Thereafter, by firing the circuit board, the conductive paste adhering to the circuit board is fixed as a conductive pattern on the circuit board.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 is a configuration diagram of a conductor pattern forming apparatus used for implementing the method of the present invention. This conductor pattern forming apparatus includes a holder 2 that holds a circuit board 1 on which a conductor pattern is to be formed, a board moving mechanism 3 that moves the holder 2 in a predetermined direction along the surface of the circuit board 1, and a heat generating section. 4a, and a head moving mechanism 5 that moves the transfer head 4 in a predetermined direction along the surface of the circuit board 1.
, the heat generating operation of the transfer head 4 and the double motion mechanism 3.5
A control unit 6 for controlling the driving of the conductor pattern to be formed, a storage unit 7 for storing data regarding the conductor pattern to be formed, and a display unit 8 for displaying the shape of the conductor pattern to be formed. 4, a tape-shaped transfer film (hereinafter referred to as transfer tape) 9 is interposed.

The circuit board 1 is an insulating plate material such as a ceramic sintered body subjected to predetermined pretreatment such as through-hole processing. Moreover, a ceramic green sheet may be used as the circuit board l. Since the holder 2 can move while holding the circuit board l on its front surface, in this example, it can move in the vertical direction of the circuit board l (in a direction perpendicular to the paper plane of FIG. 1). The substrate moving mechanism 3 is configured to move the holder 2 upward by a fixed amount from the lowered position in association with the movement of the transfer head 4. The transfer head 4 has a large number of dot-shaped heat generating parts 4a at its tip, and one or more heat generating parts 4a generate heat in response to an electric signal from the control part 6. The head moving mechanism 5 moves the transfer head 4 to the right along the surface of the circuit board l. The control section 6 is constituted by a computer, reads data regarding the conductor pattern from the storage section 7, and controls the heat generation operation of the transfer head 4 and the driving of the dual motion mechanism 3.5 based on the data.

As shown in FIG. 2, the transfer tape 9 is made by applying a conductive paste 9b to one surface of a tape-shaped base film (hereinafter referred to as base tape) 9a made of an organic film. The conductor paste 9b includes, for example, 80% by weight of conductor powder, 10% by weight of glass powder, and 710% by weight of organic binder.
It has a composition of The conductor powder in the conductor paste 9b includes:
Au, Pt, Pd.

At least one of Ag, Cu, and Ni is selected and used. In addition, the glass powder contains 5i02. B2O3,
B i, o 3. A 1tO3, P bo , S bt
o3. CdO, Cr, 03, etc. are used. The organic binder used is one that is easily peeled off from the base tape 9a when heated and easily adheres to the circuit board l. This transfer tape 9 is wound into a roll and stretched over the front surface of the circuit board l.

Next, the operation of forming a conductor pattern using the apparatus having the above configuration will be explained.

The storage unit 7 stores in advance data regarding the conductor pattern to be formed. A circuit board 1 on which a conductive pattern is to be formed is mounted on the front surface of the holder 2, and a transfer tape 9 is interposed between the surface of the circuit board 1 and the transfer head 4.

The control section 6 reads the data of the conductor pattern from the storage section 7 and displays it on the display 8. Next, the control unit 6 moves the transfer head 4 from the left start position to the right direction A along the surface of the circuit board l via the head moving mechanism 5, and also causes the transfer head 4 to correspond to the shape of the conductor pattern. supply an electrical signal. At this time, the holder 2 and the circuit board 1 are at the lowermost position, and therefore the transfer head 4 is applied to the uppermost position of the circuit board I.

The transfer head 4 causes its single or plural heat generating portions 4a to generate heat while moving in the right direction A along the uppermost position of the surface of the circuit board 1. Since the transfer tape 9 is interposed between the transfer head 4 and the circuit board l, the conductive paste 9b in the area in contact with the heat generating part 4a is peeled off from the base tape 9a and the surface of the circuit board 1 is removed. transcribed into.

As a result, the conductive paste 9b is attached to the uppermost position of the surface of the circuit board 1 in the horizontal direction in a manner corresponding to a part of the conductive pattern.

When the transfer head 4 repeatedly generates heat and reaches the end in the right direction, the transfer head 4 returns to the starting position on the left, and the circuit board 1 moves upward by a certain distance together with the holder 2. Then, the transfer head 4 repeats the above operation of generating heat while moving in the right direction A again. In this way, each time the circuit board l rises, the movement of the transfer head 4 to the right and the generation of heat are repeated, and as shown in FIG. 3, the circuit board! As a result, the conductive paste 9b is adhered to the entire surface of the circuit board 1 in a shape corresponding to the conductor pattern.

The circuit board l to which the conductive paste 9b is attached is then
Fired. By this firing, the conductor paste 9b is solidified and fixed on the circuit board 1, forming a conductor pattern.

In the above embodiment, the circuit board l and the transfer head 4 are moved together, but the transfer head 4 is of a line type having a line-shaped heating section and is fixed at a fixed position. The circuit board l may be moved relative to the head.

In this case, the transfer film is formed into a sheet that covers the entire width of the circuit board 1.

After use, the transfer tape 9 or the transfer film has some untransferred conductor paste 9b remaining therein, or the remaining conductor paste 9b is recovered using an organic solvent and reused.

<Effects of the Invention> As described above, according to the present invention, a conductor pattern can be formed in direct conjunction with a control device such as a computer that processes data regarding the conductor pattern, and the conductor pattern can be formed on the control device side. If a change is made, a conductor pattern can be immediately formed according to the shape, and the design can be easily changed.

In addition, since conductor patterns can be formed directly in conjunction with control equipment, there is no need to create originals such as screens or masks every time a design is changed, reducing the number of processes and making it possible to produce a wide variety of products in small quantities. However, there is no cost increase.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of an apparatus used for carrying out the method of the present invention;
The figure is a perspective view of the transfer tape, and FIG. 3 is an explanatory diagram showing the state of transfer of the conductive paste to the circuit board. ! ...Circuit board, 2...Holder, 4...Transfer head, 9...Transfer tape (transfer film), 9a...
Base tape (base film), 9b... conductor paste.

Claims (1)

[Claims] (1) Prepare a transfer film made by coating a conductive paste on a base film, apply a transfer head having a heat generating part to the surface of a circuit board on which a conductive pattern is to be formed via the transfer film, and The transfer head is moved relative to the transfer head, and in connection with this movement, a necessary electrical signal corresponding to the conductive pattern is input to the transfer head, and the heat generated by the heat generating part of the transfer head causes the conductive paste of the transfer film to become a circuit. A method for forming a conductor pattern, characterized by transferring the pattern onto a substrate.