JPH0770804B2 - Hybrid circuit board - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board of an electronic device, and more particularly to a transfer transfer mounting system for a plurality of electric resistance elements.

Conventional technology Conventionally, paper phenol, paper epoxy, glass cloth epoxy,
A hybrid circuit board was obtained by surface-mounting individual components on a printed wiring board based on alumina porcelain aluminum nitride or the like.

Problems to be Solved by the Invention Among individual parts, the number of resistance-pair elements is the largest, and the time and cost for mounting dust and the like are becoming enormous.

The present invention aims to provide a new mounting means for the purpose of saving the time and cost.

Means for Solving the Problems The present invention provides, as a specific means, a provisional substrate on which a plurality of resistors are formed by printing. By utilizing the fact that the printing position and shape of the resistor can be controlled by the print mask, the resistor is printed at the position where the resistor is mounted on the true substrate and at the position where it can be transferred. Thus, the transfer placement component is formed.

For transfer, cutting preparation work is performed on the temporary substrate in the form of V cut, half cut, perforation, laser processing, punching processing, etc., and transfer placement is possible by selectively pressing on the true substrate And

Action According to the present invention, the bonding to the true substrate may be performed by soldering afterwards, but a solder paste and an adhesive (conductive and non-conductive) are printed or applied on the true substrate in advance, The transfer mounting component is soldered or heat bonded to the true substrate. It goes without saying that the printing direction of the resistor element, the printing order, the number of printing layers, the number of times of printing, the thickness, the material of the electrode, the material shape and size of the resistor, the wattage, etc. can be applied by the existing technology. However, with the expansion and contraction value of the substrate material,
Some factors may be added to the cost of the resistor.

EXAMPLE An example of the present invention will be described with reference to the sectional views of FIGS.

In FIG. 1 (a), a carbon / resin-based resistor 3 is printed on the temporary substrate 1 of the present invention, baked at 150 ° C. for 120 minutes, adjusted to a predetermined resistance value, and subjected to a reflow of 215 ° C. Heat aging is applied assuming soldering. The electrode 2 of the temporary substrate 1 is the electrode of the resistor, which is printed before or after the resistor printing, and is baked before or simultaneously with the resistor baking. The V-shaped groove 6 for cutting is formed on the temporary substrate 1 from one side or both sides. The used portion of the temporary substrate 1 becomes the used piece 4, and the unused portion of the temporary substrate 1 becomes the unused piece 5.

In FIG. 1 (b), an electrode as a wiring board is provided on the true substrate 11.
Have twelve.

In FIG. 1 (c), the temporary substrate 1 of the present invention faces downward. In FIG. 1D, the temporary substrate 1 of the present invention is divided into a used piece 4 and an unused piece 5. Then, the electrode 12 of the true substrate 11 and the electrode portion 2 of the used piece 4 of the temporary substrate are brought into contact with each other,
Solder with tin-lead eutectic solder. At this time, the solder can be supplied as a paste. If the expansion coefficients of the temporary substrate 1 and the true substrate 11 are the same within the range of actual use temperature of −55 to 150 ° C., dry-curing connection using a conductive adhesive can be simplified. For example, the true substrate 11 is 6.
5 ppm / ° C., the temporary substrate 1 is 6.5 to 7.0 ppm / ° C., and the weight ratio of aramide fiber to epoxy resin is 45:55. Further, the individual component is not necessarily limited to the resistor, and can be applied to many general active elements / passive elements. In addition, carbon
Stable connection reliability can be obtained due to the low cost of the resin type resistor and the matching expansion coefficient between the electrodes of the individual parts of the aramide substrate and the base.

EFFECTS OF THE INVENTION According to the present invention, surface mounting of a large number of individual components can be performed at once, so that it is possible to save man-hours and lead time, thereby saving time and cost. By adjusting the temperature expansion / contraction rate of the organic material-based component to that of the inorganic material-based substrate, the reliability of connection during mounting and the number of mounted joints is improved.

[Brief description of drawings]

1 (a) to 1 (d) are sectional views showing an embodiment of the present invention in process steps. 1 ... Temporary substrate, 2 ... Temporary substrate electrode, 3 ... Carbon
Resin type resistor, 4 ... piece used, 5 ... piece not used,
6 ... V-shaped groove, 11 ... True substrate, 12 ... True substrate electrode.

Claims (1)

[Claims] 1. A paper comprising an electric resistance layer containing carbon powder printed on its surface and an electrode layer printed on the electric resistance layer, wherein an epoxy resin is applied to a paper made of aramide fiber. A first substrate formed by impregnating 45% of the aramide fiber with 55% of the epoxy resin by weight, and a second substrate that is a printed circuit board having an electrode layer made of copper. A hybrid circuit board, wherein an electrode layer on the second substrate is joined to an electrode layer on the electric resistor layer of the first substrate so as to face each other.