JP3242247B2 - Manufacturing method of square chip resistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a rectangular chip resistor mounted on a cross portion of a printed wiring board, for example.

[0002]

2. Description of the Related Art Conventionally, as a method of manufacturing this type of square chip resistor, for example, a configuration described in Japanese Patent Application Laid-Open No. 5-205902 is known.

In the method of manufacturing a rectangular chip resistor described in Japanese Patent Application Laid-Open No. 5-205902, a plurality of sets of ruthenium oxide resistive films are printed and formed on the surface of a first insulating plate. Then, a plurality of sets of internal electrodes are printed and formed so as to partially overlap both ends of each resistance film.

[0004] A second insulating plate is bonded to the surface of the first insulating plate on which a plurality of sets of resistive films are formed by heating and pressing. Then, the laminated insulator is appropriately divided and calcined to form a plurality of semi-finished resistors each including a composite ceramic base having a resistive film and internal electrodes connected to both ends.

[0005] Next, the semi-finished resistor is rounded at each ridge line by a barrel polishing machine. Then, an internal electrode is connected to both ends of the semi-finished resistor, a nickel plating layer and a solder plating layer are sequentially formed to form an external electrode which is a conductive portion, and a square chip resistor is formed.

[0006]

However, in the method of manufacturing a rectangular chip resistor described in Japanese Patent Application Laid-Open No. 5-205902, the area of the internal electrode connected to the resistive film exposed from the end face of the laminated insulator is reduced. Since it is small, there is a problem that a connection area with a nickel plating layer to be an external electrode is small and a connection force is weak.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an advantage in that an area of a resistive film exposed on an end face of a laminated insulator is increased, stability of adhesion between the resistive film and a conductive portion is improved, and reliability is improved. And a method for manufacturing a square chip resistor having a high resistance.

[0008]

Means for Solving the Problems] claim 1 square chip resistor manufacturing method described, the distance between the plural rows of strip-shaped resistive film
Is approximately the distance from the edge of the first insulating plate to the edge of the resistive film.
And doubled, the resistance film substantially in parallel form through the space in the width direction, the resistance on the first plane said forming a resistive film of the insulating plate on the plane of said first insulating plate While forming a strip-shaped edge conductive film on the edges on both ends in the longitudinal direction of the film,
The wide conductive film approximately twice the width dimension than the edge conductive film plural rows formed substantially in parallel via a gap in the width direction in this Enshirube conductive film,
A second insulating plate is superimposed and fixed on a plane of the first insulating plate on which the resistive film, the edge conductive film and the wide conductive film are formed, and the resistive film is formed on the first and second insulating plates. ,
A laminated insulator is formed by sandwiching the edge conductive film and the wide conductive film, and the laminated insulator is divided substantially at the center in the longitudinal direction of the wide conductive film to form an elongated insulating piece. Conductive portions are formed on both side surfaces where the cross section along the longitudinal direction of the edge conductive film and the wide conductive film is exposed, and this elongated insulating piece is divided into chips from an intermediate position between the resistive films. > Things.

[0009]

Method for manufacturing a rectangular chip resistor of the action] first aspect, the first insulating plate on a plane to form a band-shaped resistive film,
To form a strip-shaped Enshirube film in both longitudinal end edge of the resistive film, through a gap wide conductive film approximately twice the width dimension than the edge conductive film in the width direction in this Enshirube conductive film substantially A plurality of layers are formed in parallel and divided at substantially the center in the longitudinal direction of the wide conductive film. Therefore, the laminated insulator sandwiched between the first and second insulating plates is only divided vertically and horizontally. A large number of square chip resistors, which improve the connectivity between the resistive film and the conductive portion, can be easily obtained without a cut-out portion , and the distance between the plural strip-shaped resistive films can be reduced.
Approximately twice the distance from the edge of the insulating plate to the edge of the resistive film
And make the width dimension of the wide conductive film approximately twice as large as the edge conductive film.
Thereby, the first insulating plate and the second insulating plate are overlapped.
When dividing the laminated insulator after the
At least one of the position of the wide conductive film and the resistance film
Increased degree of freedom increases yield when dividing laminated insulators
Mari is you improve.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a square chip resistor manufactured by a method of manufacturing a square chip resistor according to the present invention.

In FIG. 1, reference numeral 1 denotes a square chip resistor.
This square chip resistor 1 is formed by laminating a pair of first and second insulating plates 2 and 3 formed in a substantially rectangular flat plate shape from an insulating ceramic material plate or a synthetic resin plate. .

In the rectangular chip resistor 1, a strip-shaped resistive film 5 having a longitudinal direction along the longitudinal direction is sandwiched between the first and second insulating plates 2, 3 substantially at the center. ing. Further, conductive films 6, 6 are formed at both ends in the longitudinal direction of the resistive film 5 so that the longitudinal directions are substantially perpendicular to the vertical direction.

At both ends of the rectangular chip resistor 1 in the longitudinal direction, conductive portions 7 and 7 are formed by nickel plating, solder plating, or the like on both ends of the resistive film 5 and the conductive films 6 and 6, respectively. It is formed in contact. Further, conductive portions 7 and 2 are provided at both ends of the rectangular chip resistor 1 in the longitudinal direction.
An electrode 8 is formed by nickel plating, solder plating, or the like so as to cover 7.

Next, the steps of manufacturing the above-mentioned square chip resistor will be described with reference to the drawings.

First, as shown in FIG. 2, the first insulating plate 2 is formed into a substantially rectangular flat plate shape using a substantially rectangular flat plate-shaped ceramic before firing.

Then, on the plane of the first insulating plate 2,
As shown in FIG. 3, the belt-shaped resistive films 5, 5 are formed by printing a plurality of strips substantially in parallel with an interval in the width direction.

When forming the resistive films 5, 5, the distance a between the resistive films 5, 5 is approximately twice as large as the distance b from the edge of the first insulating plate 2 to the edge of the resistive film 5. a = 2b).

When the first insulating plate 2 is a ceramic material plate, a material such as silver, palladium, gold or tungsten, molybdenum, ruthenium, tin or the like is used as a material of the resistance film 5. When the first insulating plate 2 is a synthetic resin plate as a dispersed resistance paste, a synthetic resin resistance paint using silver or carbon as a resistive substance is used.

On the plane of the first insulating plate 2 on which the resistive films 5, 5 are formed, as shown in FIG. The edge conductive films 6a, 6a are formed, and the edge conductive films 6a, 6a are interposed between the edge conductive films 6a, 6a.
A plurality of strip-shaped wide conductive films 6b, 6b each having a width dimension d (d = 2c) substantially twice as large as the width dimension c of a are formed by printing in parallel in the width direction at intervals.

The edge conductive film 6a and the wide conductive film 6b
When the first insulating plate 2 is a ceramic material plate, a conductive paste in which a conductive substance such as silver, palladium, gold, tungsten, or molybdenum is dispersed in glass, resin, or the like is used as the first insulating plate 2. When the plate 2 is a synthetic resin plate, a synthetic resin resistance paint using silver or the like as a conductive material is used.

Next, as shown in FIG.
Resistive film 5, the Enshirubedenmaku 6a and the wide conductive film 6b is on are formed planar, the second insulating plate 3 so I if overlapping of the plate shape of the same material as the first insulating plate 2, 0.99 ° C. The laminated insulator 9 is formed by heating at about 200 ° C. Note that the first and second
When the insulating plates 2 and 3 are synthetic resin plates, they are bonded with an adhesive.

Then, on the upper surface of the second insulating plate 3 of the laminated insulator 9, as shown in FIG. The dividing groove 10 is formed. Further, the laminated insulator 9 is cut , that is, divided at a substantially central portion in the longitudinal direction of the wide conductive film 6b in a direction in which the longitudinal direction of the strip-shaped resistive film 5 is cut off.
Form 11.

Thereafter, the elongated insulating piece 11 is fired. In addition,
The firing temperature is determined by the resistance film 5, the edge conductive film 6a, and the wide conductive film 6b.
If the material is a thick film resistor paste such as silver, palladium, gold, ruthenium or the like, the paste is fired at 800 ° C. to 900 ° C. to sinter the first and second insulating plates 2 and 3. When the material of the resistance film 5, the edge conductive film 6a, and the wide conductive film 6b is tungsten or molybdenum, baking is performed at 1400 ° C. to 1600 ° C. in an N ₂ H ₂ mixed gas.

High temperature sintering is more preferable for ceramification, but silver, palladium, gold, ruthenium, etc.
If the temperature is 0 ° C. or more, the material is melted.

Next, both end surfaces in the width direction of the elongated insulating piece 11, ie, the cross section in the width direction of the resistive film 5, and the cross section of the conductive film 6, ie, the side surface of the edge conductive film 6a or the longitudinal direction of the wide conductive film 6b. the surface section is exposed, the conductive paste or conductive coating, resistive film 5, and the conductive film 6, i.e. the edge guide
It applied to conduct the conductive film 6a or the wide conductive film 6b,
By baking or heating and drying, conductive portions 7, 7 are formed on both side surfaces of the elongated insulating piece 11, as shown in FIGS.

Then, the elongated insulating piece 11 is divided from the position of the dividing groove 10, and as shown in FIG. 8, a rectangular parallelepiped chip piece 12 having conductive portions 7, 7 formed on both end surfaces in the longitudinal direction is formed. .

Next, nickel conductive plating or solder plating is applied to the conductive portions 7, 7 of the chip piece 12 to form electrodes 8, 8,
To form the square chip resistor 1 shown in FIG.
The electrodes 8 , 8 may be formed by applying a nickel electrolytic plating and then applying a layer of solder plating on the surface of the nickel electrolytic plating.

In the above-described embodiment, the strip-shaped edge conductive film 6a is formed on the plane of the first insulating plate 2 on which the strip-shaped resistance film 5 is formed, located at both edges in the longitudinal direction of the resistance film 5. as well as, the edge conductive film 6a than the width dimension substantially twice wider wide conductive film 6b, plural rows formed substantially in parallel via a gap in the width direction in this Enshirubedenmaku 6a, longitudinal wide conductive film 6b Minutes in the approximate center of the direction
Order to split, is divided into a substantially central position between the resistive film 5, laminated insulators were sandwiched by the first and second insulating plates 2 and 3 9
Are divided vertically and horizontally, and the square chip resistor 1 can be easily formed in a large amount at once without a cut-out portion. Further, since the resistive film 5 and the conductive film 6 continuous with the resistive film 5, that is, the cross-sections of the edge conductive film 6a and the wide conductive film 6b are exposed, the cross-section of the resistive film 5 simply formed on the plane of the insulating plates 2, 3 is As compared with the above, the connection area between the conductive portion 7 formed on the elongated insulating piece 11 and the resistive film 5 via the conductive film 6 can be increased, the connection becomes very strong, and a highly reliable electrode can be obtained.

The resistance film 5 is formed on the plane of the first insulating plate 2.
Is formed, the distance between the resistive films 5 is set to a first distance.
Make the distance from the edge of the insulating plate 2 to the edge of the resistive film 5 approximately twice as large.
And the edges of the first insulating plate 2 at both ends on the plane.
Wide with a width twice as large as the formed edge conductive films 6a, 6a
The conductive films 6b, 6b are spaced apart from the edge conductive films 6a, 6a in the width direction.
By forming the first insulating plate 2 and the second insulating
The laminated insulator 9 after overlapping the edge plate 3 is divided
When performing, the edge conductive film 6a, the wide conductive film 6b and the resistance film 5
Since the degree of freedom of at least one position increases, the product
The yield when dividing the layer insulator 9 can be improved.

In the above embodiment, two or more resistive films 5 and edge conductive films 6a,
The wide conductive film 6b can also be formed.

Further, it has been described to form a Enshirube film 6a on the first insulating plate 2, each conductive film to near the edge of the first insulating plate 2
Instead of forming the resistive films 6a and 6b and the resistive film 5, the cutoff may be finally cut off. The width and thickness of each of the conductive films 6a and 6b and the resistance film 5 are appropriately set.

[0032]

Method for manufacturing a rectangular chip resistor according to claim 1, wherein, according to the invention is, on the plane of the first insulating plate forming the band-shaped resistive film, in the longitudinal direction of both ends of the edges of the resistive film strip to form a Enshirubedenmaku, the edge conductive film plural rows formed substantially parallel to substantially twice the wide conductive film than the width of, for dividing the longitudinal direction of the substantially center of the wide conductive film, first and second By simply dividing the laminated insulator sandwiched between the two insulating plates vertically and horizontally, square chip resistors with improved connectivity between the resistive film and the conductive portion can be easily mass-produced without any cut-off portions . Multiple strips
The distance between the resistive films from the edge of the first insulating plate to the edge of the resistive film.
To approximately twice the distance to
The first insulating plate and the second insulating plate are approximately twice as large as the conductive film.
When dividing a laminated insulator after laminating a board
At least one of an edge conductive film, a wide conductive film, and a resistive film.
Since the degree of freedom of the position of the shift increases, the laminated insulator can be separated.
Ru can improve the yield at the time of the split.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing one embodiment of a square chip resistor manufactured by a method of manufacturing a square chip resistor according to the present invention.

FIG. 2 is a perspective view showing a first insulating plate according to the first embodiment;

FIG. 3 is a perspective view showing a state in which a resistive film is formed on a first insulating plate.

FIG. 4 is a perspective view showing a state where a conductive film is formed on the first insulating plate on which the resistance film is formed.

FIG. 5 is a perspective view showing the laminated insulator in a state where the second insulating plates are overlapped with each other;

FIG. 6 is a perspective view showing the elongated insulating piece.

FIG. 7 is a plan view showing a state in which a conductive portion is formed on the elongated insulating piece.

FIG. 8 is a plan view showing the same chip piece.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Square chip resistor 2 1st insulating plate 3 2nd insulating plate 5 Resistive film 6a Edge conductive film 6b Wide conductive film 7 Conductive part 9 Laminated insulator 11 Slender insulating piece

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01C 17/06 H01C 7/00

Claims (1)

(57) [Claims] A distance between a plurality of strip-shaped resistive films is set to a first distance.
Approximately twice the distance from the edge of the insulating plate to the edge of the resistive film
Te, length of the first said resistive film on the plane of the insulating plate through a distance in the width direction substantially parallel to the resistive film on the first plane said forming a resistive film of the insulating plate to form a strip-shaped Enshirube film in the direction of both end sides of the edges, substantially parallel to the plurality condition through a gap in the width direction width dimension than the edge conductive film a wide conductive film substantially twice this Enshirube conductive film Forming a second insulating plate on a surface of the first insulating plate on which the resistive film, the edge conductive film, and the wide conductive film are formed, and fixing the second insulating plate on the first and second insulating plates; The resistive film ,
A laminated insulator is formed by sandwiching the edge conductive film and the wide conductive film, and the laminated insulator is formed at substantially the center in the longitudinal direction of the wide conductive film.
An elongated insulating piece is formed by dividing, and conductive portions are formed on both sides of the elongated insulating piece where the cross sections along the longitudinal direction of the edge conductive film and the wide conductive film are exposed. A method of manufacturing a square chip resistor, wherein each of the chips is divided into chips from an intermediate position between the films.