Chip resistor and method for producing same

Patent metadata

Field	Value
Publication number	US-10109398-B2
Application number	US-201515513725-A
Country	US
Kind code	B2
Filing date	Jul 22, 2015
Priority date	Sep 25, 2014
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

The invention is to provide a chip resistor suitable for lowering an initial resistance value. A chip resistor 1 according to the present invention is provided with: an insulating substrate 2 ; a pair of front electrodes 3 which are provided on a front surface of the insulating substrate 2 so as to face each other with a predetermined interval therebetween; a resistive element 4 which is provided so as to bridge the front electrodes 3 ; a pair of auxiliary electrodes 5 which are provided so as to cover the front electrodes 3 and overlap end portions of the resistive element 4 ; and the like. The chip resistor 1 is configured such that: the front electrodes 3 are formed of a material which contains 1 to 5 wt % Pd and the balance Ag; and the auxiliary electrodes 5 are formed of a material which contains 15 to 30 wt % Pd and a metal material (e.g. Au) lower in resistivity than Pd and the balance Ag.

First claim

The invention claimed is:

1. A chip resistor comprising: an insulating substrate; a pair of front electrodes which are provided on a front surface of the insulating substrate so as to face each other with a predetermined interval therebetween; a resistive element which is provided to extend onto the pair of front electrodes; and auxiliary electrodes which are provided so as to cover the front electrodes and overlap end portions of the resistive element; wherein:
the front electrodes are formed of a material which contains 1 to 5 wt % palladium and the balance silver, and the auxiliary electrodes are formed of a material containing 15 to 30 wt % palladium and a metal material lower in resistivity than palladium and the balance silver.

2. A chip resistor according to claim 1 , wherein:
a countervailing distance between the auxiliary electrodes is set to be narrower than a countervailing distance between the front electrodes.

3. A chip resistor according to claim 1 , wherein:
the resistive element has a resistance value which has been lowered by re-sintering.

4. A method for producing a chip resistor comprising:
a step of printing and sintering a paste material on a front surface of an insulating substrate to form a pair of front electrodes, the paste material containing silver as a main component;
a step of printing and sintering a resistive paste to form a resistive element so that the resistive element can extend onto the pair of front electrodes;
a step of bringing probes into contact with the pair of front electrodes to measure an initial resistance value of the resistive element;
a step of forming a pair of auxiliary electrodes so as to cover the front electrodes and overlap end portions of the resistive element only when the initial resistance value is higher than a reference resistance value; and
a step of re-sintering the resistive element after formation of the auxiliary electrodes so as to lower the initial resistance value; wherein:
the front electrodes are formed of a material containing 1 to 5 wt % palladium and the balance silver; and
the auxiliary electrodes are formed by printing and sintering a paste material containing 15 to 30 wt % palladium and a metal material lower in resistivity than palladium and the balance silver.

5. A method for producing a chip resistor according to claim 4 , wherein:
a countervailing distance between the auxiliary electrodes can be changed in accordance with a divergence amount of the initial resistance value from the reference resistance value.

6. A method for producing a resistor chip according to claim 4 , wherein:
the auxiliary electrodes are superimposed on end portions of the resistive element so that a countervailing distance between the auxiliary electrodes can be narrower than a countervailing distance between the front electrodes.

Assignees

• Koa Corp

Inventors

• Matsumoto Kentaro

Classifications

• H01C7/20

  the resistive layer or coating being tapered · CPC title

• H01C17/283

  Precursor compositions therefor, e.g. pastes, inks, glass frits · CPC title

• H01C1/142

  the terminals or tapping points being coated on the resistive element · CPC title

• H01C17/06513

  characterised by the resistive component · CPC title

• H01C7/003 Primary

  Thick film resistors · CPC title