摘要 |
The present invention provides a method of producing a resistance element incorporated in a printed circuit board at an accuracy of resistance value of ±1% or less, at low cost and with a good yield while the resistance element formed by a resistor paste is incorporated. A method of producing a printed circuit board incorporating a resistance element includes: preparing a double-sided copper clad board having a first metallic foil on one face of an insulating base material thereof and a second metallic foil on the other face of the insulating base material thereof; providing at least a pair of electrodes on one of the metallic foils; printing a resistor paste between the electrodes to form a resistor; preparing a circuit board having at least one wiring layer; causing a layer on which the resistor paste is formed to oppose the circuit board to layer the double-sided copper clad board on the circuit board; forming openings in the first and the second metallic foils; and emitting laser through the openings to partly remove the insulating base material and the resistor paste to adjust resistance value. A conformal mask for etching may be formed on the second metallic foil to form openings in the insulating base material by etching to emit laser through the openings.
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