JPH11307320A - Chip resistor and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a filletless type chip resistor in which burrs or ships can be prevented from being generated in an electrode at the dividing. SOLUTION: In this method for manufacturing a chip resistor 10, lower layer electrodes 2 are arranged across a vertical groove on the upper face of an original plate, in which plural insulating substrates prior to division are vertically and horizontally blocked along a vertical groove and a horizontal groove, and the lower later electrode 2 are connected through resistor film 3, and the entire face of the resistor film 3 is covered by a lower layer protecting film 4 and the resistor film 3 is subjected to laser trimming from the upper part of the lower layer protecting film 4, and the lower layer protecting film 4 is covered by an upper protecting film 5. After or at the same time as the formation of the upper protecting film 5, separated layers 6 extended along the vertical groove are formed, and then upper electrodes 7 are arranged between the upper layer protecting film 5 and the separated layers 6. Afterwards, the original plate is divided from the vertical groove and the horizontal groove, and plated films are formed on the upper electrodes 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a chip resistor, and more particularly to a so-called filletless type which can be solder-bonded to a land of a wiring board in a direction toward an end face electrode of the chip resistor without providing a solder fillet. The present invention relates to a method for manufacturing a chip resistor.

[0002]

2. Description of the Related Art In a chip resistor, a land of a wiring board and an end face electrode of the resistor have been conventionally soldered to each other by a solder fillet. The demand for higher integration of component mounting density has increased, and in order to reduce the solder occupation area as much as possible, a fillet that solders the upper electrode of the resistor without providing a solder fillet in the direction of the end face electrode side of the chip resistor with respect to the land There is a long-felt need for a chip-type chip resistor.

In such a filletless type chip resistor, the height of the electrodes needs to be equal to or slightly protrude from the upper surface of the protective film covering the resistive film between the electrodes. Must be thicker.

[0004]

However, in the chip resistor, electrodes, a resistive film, and a protective film are provided on an original plate on which a large number of insulating substrates are divided by vertical and horizontal dividing grooves, and then the dividing grooves are formed. However, since the electrodes are provided across the dividing grooves, if the thickness of the electrodes is ensured, the division of the electrodes during the original plate division is not performed smoothly, and flash is formed on the divided surfaces of the electrodes. There is a problem that chipping occurs. Such burrs and chips may cause, for example, clogging of a chute in a manufacturing process, a suction error from a taping cavity in a mounting machine, or a decrease in a solder bonding area due to a decrease in a solder bonding area. It also becomes a hindrance factor in further downsizing the vessel.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to prevent burrs or chips from being generated in an electrode when dividing an original plate, and to provide an electrode as a filletless type resistor. An object of the present invention is to provide a method for manufacturing a chip resistor capable of ensuring a sufficient thickness.

[0006]

According to a first aspect of the present invention, there is provided a method of manufacturing a chip resistor according to the present invention, in which an upper surface of an electrode is solder-bonded to a land of a wiring board. A method for manufacturing a filletless type chip resistor, comprising: a first division groove and a second division groove which are orthogonal to each other, and the first division groove straddles a large number of insulating substrates on an original plate. Arranging a pair of lower electrodes at both ends of the insulating substrate, arranging a resistive film communicating between the lower electrodes, trimming the resistive film, and protecting the resistive film A step of coating with a film, a step of forming a separation layer that straddles the first division groove relatively narrowly, and extends along the first division groove, and between the protection film and the separation layer. Disposing an upper layer electrode; A step of dividing along the first split groove and second split groove, characterized in that it comprises a step of forming a plating layer on the upper electrode.

That is, in this manufacturing method, the electrode has a two-layer structure including a lower electrode and an upper electrode, and a resistive film is connected to the lower electrode, while the upper electrode of the filletless chip resistor is connected to the land of the wiring board. The thickness of the electrode for solder bonding is secured by the upper layer electrode, and the separation layer is formed in advance along the first division groove so that the upper layer electrode thus thickened does not cover the first division groove. Accordingly, when the original plate is divided, the separation layer is divided, but the upper layer electrode is not divided, so that the occurrence of burrs and chips in the upper layer electrode can be avoided.

[0008] The height of the upper layer electrode is approximately the same as or slightly protrudes from the upper surface of the protective film in order to secure the solder connection to the land of the wiring board. In addition, the upper electrode may be provided independently for each insulating substrate so as not to cover the second dividing groove, or may be continuously provided between adjacent insulating substrates while straddling the second dividing groove. Is also good.

In the present manufacturing method, the protective film may have a single-layer structure or a two-layer structure. In the case of the two-layer structure, after trimming the resistive film from above the lower protective film, the protective film is formed. Is coated. The protective film (the upper protective film in the case of the two-layer structure) and the separation layer can be formed sequentially or simultaneously.

[0010] A method of manufacturing the chip resistor according to the present invention described in claim 2 (hereinafter referred to as "the present manufacturing method").
Is a method of manufacturing a filletless type chip resistor in which an upper surface of an electrode is solder-bonded to a land of a wiring board, and a large number of insulating substrates are formed by a first divided groove and a second divided groove which are orthogonal to each other. Arranging a pair of lower electrodes at both ends of the insulating substrate over the first division groove on the original plate to be partitioned, arranging a resistive film communicating between the lower electrodes, Trimming the film, and forming a pair at both ends of the insulating substrate, and protecting the entire surface of the insulating substrate with a protective film except for an uncovered portion inside the first and second dividing grooves. Coating, arranging an upper electrode on the uncoated portion, dividing the original plate along the first and second division grooves, and forming a plating film on the upper electrode. Forming step To.

In this manufacturing method, a protective film (in the case of a double structure) is formed on the entire surface of the insulating substrate except for both ends (uncovered portions) of the insulating substrate inside the first dividing groove and the second dividing groove. An upper protective film is formed, and an upper electrode is disposed on the uncovered portion following this step, which is different from the present manufacturing method. Other basic steps are the same as the present manufacturing method.

In the present manufacturing method, the portion of the protective film (the upper protective film in the case of the double structure) straddling the first division groove serves as a separation layer in the present production method, and the first division groove and the first division groove are formed. Since the upper electrode is formed on the uncovered portion inside the second division groove, when mounting a plurality of chip resistors obtained by this manufacturing method on a substrate, the contact arrangement is made adjacent to the division surface of the second division groove. However, no short circuit occurs between the resistors, and the mounting area can be effectively used.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view of a chip resistor 10 obtained by the present manufacturing method, and FIG. 2 is a sectional view taken along the line AA 'of FIG. The chip resistor 10 includes a rectangular chip-shaped insulating substrate 1, a pair of lower-layer electrodes 2 disposed on both right and left ends of the insulating substrate 1, and a resistance film 3 communicating between the lower-layer electrodes 2.
A lower protective film 4 covering the resistive film 3; an upper protective film 5 covering the lower protective film 4; a separation layer 6 formed on the lower electrode on the left and right ends on the insulating substrate 1; An upper electrode 7 is provided between the upper protective film 5 and the separation layer 6, and a plating film 8 formed on the upper electrode 7.

The manufacturing process of the chip resistor 10 is as follows.

Step 1 (see FIG. 3);
Vertical groove 1 as a dividing groove and horizontal groove w as a second dividing groove
The lower electrode 2 made of a thick-film glaze-based conductive material is disposed on the upper surface of an original plate made of, for example, alumina ceramic or the like, which divides a large number of insulating substrates 1 before and after division.

Step 2 (see FIG. 4): A thick glaze-based resistive film 3 for connecting the lower electrodes 2 is provided.

Step 3 (see FIG. 5): The entire surface of the resistive film 3 is covered with the lower protective film 4 of the thick glaze glass.

Step 4 (see FIG. 6): Laser trimming for correcting the resistance value is performed on the resistive film 3 from above the lower protective film 4, thereby forming a trimming groove 3 '.

Step 5 (see FIG. 7): The lower protective film 4 is covered with the upper protective film 5 to fill the trimming groove 3 '. The upper protective film 5 is provided continuously between the adjacent insulating substrates 1 in the vertical direction while straddling the horizontal groove w.

Step 6 (see FIG. 7): The longitudinal groove 1 is straddled relatively narrowly (compared with the lower electrode 2) and is extended between the insulating substrates 1 along the longitudinal groove 1 (including on the lower electrode 2). A separation layer 6 is formed. Step 6 can be performed simultaneously with step 5.

Step 7 (see FIG. 8): An upper electrode 7 is provided between the upper protective film 5 and the separation layer 6.

The height of the upper electrode 7 is set so as to be equal to or slightly protrude from the upper surface of the upper protective film 5.
The material of the upper electrode 7 can be formed by overlapping a plurality of times. In the case where thick glass glaze glass is used as the material of the upper protective film 5 in the steps 5 to 7, the separation layer 6 is also made of the same thick glass glaze glass and the upper electrode 7
Is a thick film glaze-based conductive material having a firing temperature equal to or lower than the firing temperature of the upper protective film 5 so that the upper electrode 7 does not cover the entire surface of the separation layer 6. And On the other hand, when a resin-based paint is used as the material of the upper protective film 5, the separation layer 6 is also made of the same resin-based paint, and the upper electrode 7 is also made of a resin-based conductive paint.

Step 8: The original plate is successively divided along the vertical groove 1 and then along the horizontal groove w. The separation of the separation layer 6 by the division of the vertical groove 1 does not divide the upper layer electrode 7.

Step 9: A plating film 8 composed of nickel plating and solder plating (tin-lead) is formed on the upper electrode 7 to obtain a chip resistor 10.

In the above embodiment, as shown in FIG.
Since the upper and lower ends of the upper electrode 7 are arranged inside the lateral groove w,
Even if a plurality of chip resistors 10 are arranged side by side in contact with the divided surface of the lateral groove w, a short circuit between the resistors 10 is avoided, and the mounting area of the resistors 10 can be effectively utilized. On the other hand, the upper electrode 7 can be extended in the vertical direction while straddling the horizontal groove w. In this case, since the width of the upper electrode 7 over the horizontal groove w is narrow, the division of the horizontal groove w is easy, and
No burrs or chips that adversely affect the divided surface from the lateral groove w are generated.

FIG. 9 is a plan view of the chip resistor 20 obtained by the present manufacturing method, and FIG. 10 is a sectional view taken along the line BB 'of FIG. Parts common to the chip resistor 10 are denoted by the same reference numerals. The difference between the chip resistor 20 and the chip resistor 10 is that the upper protective film 15 is formed on the entire surface of the insulating substrate 1 except for the uncovered portion 17 ′ without providing the independent separating layer 6. And the uncovered portion 17 ′ is formed between the portion that straddles the vertical groove 1 and the uncovered portion 17 ′.
In addition, since it is set inside the horizontal groove w, the upper electrode 7 provided in the uncovered portion 17 'does not cover the horizontal groove w. Since the upper layer electrode 7 does not cover the lateral groove w, the chip resistor 20 can always avoid short circuit in the adjacent arrangement from the lateral groove dividing surface.

In the manufacturing process of the chip resistor 20, first, after the same processes as the above-described processes 1 to 4 for the chip resistor 10, as shown in FIG. formed on the entire surface of the insulating substrate 1 except for the pair of left and right uncovered portions 17 ′ inside w, and then the uncovered portions 17 ′
The upper electrode 7 is provided. Thereafter, steps 8 and 9 described above are performed.

[0029]

As described above, in the present manufacturing method,
By forming the separation layer along the first dividing groove,
The upper layer electrode having the ensured thickness is prevented from covering the first dividing groove, and it is possible to avoid burrs and chipping of the upper layer electrode at the time of dividing the original plate, and is required as a filletless type chip resistor. An occupied area required for the solder connection between the upper surface electrode and the land of the mounting board can be reliably secured, which contributes to further downsizing of the chip resistor.

In the present manufacturing method, in addition to having the advantages of the present manufacturing method, since the electrodes do not always contact the dividing surface of the second dividing groove, a plurality of chip resistors are arranged adjacent to the second dividing groove dividing surface. Even if they are arranged, a short circuit between the adjacent members can be avoided, and the adjacent space can be reduced to effectively use the mounting area.

[Brief description of the drawings]

FIG. 1 is a plan view showing a chip resistor obtained according to the present invention.

FIG. 2 is a sectional view taken along line A-A 'of FIG.

FIG. 3 is a plan view schematically showing a step 1 of the present invention.

FIG. 4 is a plan view schematically showing step 2 of the present invention.

FIG. 5 is a plan view schematically showing a step 3 of the present invention.

FIG. 6 is a plan view schematically showing step 4 of the present invention.

FIG. 7 is a plan view schematically showing steps 5 and 6 of the present invention.

FIG. 8 is a plan view schematically showing step 7 of the present invention.

FIG. 9 is a plan view showing another chip resistor obtained according to the present invention.

FIG. 10 is a sectional view taken along line B-B 'of FIG.

FIG. 11 is a plan view schematically showing another upper protective film forming step of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate 2 Lower electrode 3 Resistive film 3 'Trimming groove 4 Lower protective film 5, 15 Upper protective film 6 Separation layer 7 Upper electrode 8 Plating film 10, 20 Chip resistor 17' Uncovered part

[Procedure amendment]

[Submission date] August 2, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of Invention] chip resistor and a method of manufacturing

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a chip resistor and a chip resistor.
In particular, the present invention relates to a so-called filletless type chip resistor which can be solder-bonded to a land of a wiring board in a direction of an end face electrode side of the chip resistor without providing a solder fillet , and a method of manufacturing the same .

[0002]

2. Description of the Related Art In a chip resistor, a land of a wiring board and an end face electrode of the resistor have been conventionally soldered to each other by a solder fillet. The demand for higher integration of component mounting density has increased, and in order to reduce the solder occupation area as much as possible, a fillet that solders the upper electrode of the resistor without providing a solder fillet in the direction of the end face electrode side of the chip resistor with respect to the land There is a long-felt need for a chip-type chip resistor.

In such a filletless type chip resistor, the height of the electrodes needs to be equal to or slightly protrude from the upper surface of the protective film covering the resistive film between the electrodes. Must be thicker.

[0004]

However, in the chip resistor, electrodes, a resistive film, and a protective film are provided on an original plate on which a large number of insulating substrates are divided by vertical and horizontal dividing grooves, and then the dividing grooves are formed. However, since the electrodes are provided across the dividing grooves, if the thickness of the electrodes is ensured, the division of the electrodes during the original plate division is not performed smoothly, and flash is formed on the divided surfaces of the electrodes. There is a problem that chipping occurs. Such burrs and chips may cause, for example, clogging of a chute in a manufacturing process, a suction error from a taping cavity in a mounting machine, or a decrease in a solder bonding area due to a decrease in a solder bonding area. It also becomes a hindrance factor in further downsizing the vessel.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to prevent burrs or chips from being generated in an electrode when dividing an original plate, and to provide an electrode as a filletless type resistor. chip resistor which can ensure a thickness of and to provide a <br/> manufacturing method.

[0006]

Means for Solving the Problems The present invention according to claim 1
The chip resistor according to the present invention (hereinafter referred to as “the present invention”)
Solder the upper surface of the electrode to the land of the wiring board
A fitless type chip resistor, wherein the chip resistor
A pair of lower electrodes arranged on both left and right ends of the insulating substrate
And the trimmed contact between the lower electrodes
A resistive film, a protective film covering the resistive film, and the insulating substrate
A separation layer formed on the lower electrode on both ends on the upper and lower sides,
Between the protective film on the layer electrode and the separation layer, and
On the inner side of the upper and lower ends of the insulating substrate,
And an upper electrode disposed at least as high as the surface.
Features. In the present invention, the upper electrode is connected to the edge of the insulating substrate.
Because it was arranged inside the separation layer provided along
Prevents burrs and chipping due to its own division,
Solder to the wiring board by making it higher than the upper surface of the protective film
The combination was assured. According to a second aspect of the present invention, there is provided a chip resistor manufacturing method (hereinafter, referred to as "the present manufacturing method") for manufacturing a filletless chip resistor in which an upper surface of an electrode is soldered to a land of a wiring board. A first divisional groove and a second divisional groove, which are orthogonal to each other, form a pair at both ends of the insulating substrate over the first divisional groove on an original plate that partitions a large number of insulating substrates. Arranging a lower electrode, arranging a resistive film communicating between the lower electrodes, trimming the resistive film, covering the resistive film with a protective film, Of the first groove is relatively narrow.
Forming a separation layer extending along the division groove, arranging an upper layer electrode between the protective film and the separation layer, and dividing the original plate into the first division groove and the second division groove. The method includes a step of dividing along the groove and a step of forming a plating film on the upper electrode.

That is, in this manufacturing method, the electrode has a two-layer structure including a lower electrode and an upper electrode, and a resistive film is connected to the lower electrode, while the upper electrode of the filletless chip resistor is connected to the land of the wiring board. The thickness of the electrode for solder bonding is secured by the upper layer electrode, and the separation layer is formed in advance along the first division groove so that the upper layer electrode thus thickened does not cover the first division groove. Accordingly, when the original plate is divided, the separation layer is divided, but the upper layer electrode is not divided, so that the occurrence of burrs and chips in the upper layer electrode can be avoided.

[0008] The height of the upper layer electrode is approximately the same as or slightly protrudes from the upper surface of the protective film in order to secure the solder connection to the land of the wiring board. In addition, the upper electrode may be provided independently for each insulating substrate so as not to cover the second dividing groove, or may be continuously provided between adjacent insulating substrates while straddling the second dividing groove. Is also good.

In the present manufacturing method, the protective film may have a single-layer structure or a two-layer structure. In the case of the two-layer structure, after trimming the resistive film from above the lower protective film, the protective film is formed. Is coated. The protective film (the upper protective film in the case of the two-layer structure) and the separation layer can be formed sequentially or simultaneously.

[0010] The chip resistor according to the third aspect of the present invention.
(Hereinafter referred to as "the present invention")
Fitless type chip that solders the upper surface of the counter electrode
Wherein the chip resistor is located on the left side of the insulating substrate.
A pair of lower electrodes disposed at both right ends, between the lower electrodes;
Contact the trimmed resistive film with the insulating substrate
Non-contact on the lower electrode inside the left, right, upper and lower ends of the plate
The entire surface of the insulating substrate was covered, leaving as a covering portion
The protective film and the uncovered portion surrounded by the protective film are covered with the protective film.
The upper electrode, which is arranged at least as high as the upper surface of the protective film,
It is characterized by including. In the present invention,
The same upper layer electrode as that of the present invention is used as an insulating base for forming a dividing groove.
Prevents burrs and chips by separating from the board edge,
Not only ensures soldering to
By disposing the upper layer electrode on the uncovered part
The formation of a separation layer to keep the distance from the edge of the insulating substrate
be able to. The manufacturing method of the chip resistor according to the present invention described in claim 4 (hereinafter referred to as “the present manufacturing method”).
Is a method of manufacturing a filletless type chip resistor in which an upper surface of an electrode is solder-bonded to a land of a wiring board, and a large number of insulating substrates are formed by a first divided groove and a second divided groove which are orthogonal to each other. Arranging a pair of lower electrodes at both ends of the insulating substrate over the first division groove on the original plate to be partitioned, arranging a resistive film communicating between the lower electrodes, Trimming the film, and forming a pair at both ends of the insulating substrate, and protecting the entire surface of the insulating substrate with a protective film except for an uncovered portion inside the first and second dividing grooves. Coating, arranging an upper electrode on the uncoated portion, dividing the original plate along the first and second division grooves, and forming a plating film on the upper electrode. Forming step To.

In this manufacturing method, a protective film (in the case of a double structure) is formed on the entire surface of the insulating substrate except for both ends (uncovered portions) of the insulating substrate inside the first dividing groove and the second dividing groove. An upper protective film is formed, and an upper electrode is disposed on the uncovered portion following this step, which is different from the present manufacturing method. Other basic steps are the same as the present manufacturing method.

In the present manufacturing method, the portion of the protective film (the upper protective film in the case of the double structure) straddling the first division groove serves as a separation layer in the present production method, and the first division groove and the first division groove are formed. Since the upper electrode is formed on the uncovered portion inside the second division groove, when mounting a plurality of chip resistors obtained by this manufacturing method on a substrate, the contact arrangement is made adjacent to the division surface of the second division groove. However, no short circuit occurs between the resistors, and the mounting area can be effectively used.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view of a chip resistor 10 obtained by the present manufacturing method, and FIG. 2 is a sectional view taken along the line AA 'of FIG. The chip resistor 10 includes a rectangular chip-shaped insulating substrate 1, a pair of lower-layer electrodes 2 disposed on both right and left ends of the insulating substrate 1, and a resistance film 3 communicating between the lower-layer electrodes 2.
A lower protective film 4 covering the resistive film 3; an upper protective film 5 covering the lower protective film 4; a separation layer 6 formed on the lower electrode on the left and right ends on the insulating substrate 1; An upper electrode 7 is provided between the upper protective film 5 and the separation layer 6, and a plating film 8 formed on the upper electrode 7.

The manufacturing process of the chip resistor 10 is as follows.

Step 1 (see FIG. 3);
Vertical groove 1 as a dividing groove and horizontal groove w as a second dividing groove
The lower electrode 2 made of a thick-film glaze-based conductive material is disposed on the upper surface of an original plate made of, for example, alumina ceramic or the like, which divides a large number of insulating substrates 1 before and after division.

Step 2 (see FIG. 4): A thick glaze-based resistive film 3 for connecting the lower electrodes 2 is provided.

Step 3 (see FIG. 5): The entire surface of the resistive film 3 is covered with the lower protective film 4 of the thick glaze glass.

Step 4 (see FIG. 6): Laser trimming for correcting the resistance value is performed on the resistive film 3 from above the lower protective film 4, thereby forming a trimming groove 3 '.

Step 5 (see FIG. 7): The lower protective film 4 is covered with the upper protective film 5 to fill the trimming groove 3 '. The upper protective film 5 is provided continuously between the adjacent insulating substrates 1 in the vertical direction while straddling the horizontal groove w.

Step 6 (see FIG. 7): The longitudinal groove 1 is straddled relatively narrowly (compared with the lower electrode 2) and is extended between the insulating substrates 1 along the longitudinal groove 1 (including on the lower electrode 2). A separation layer 6 is formed. Step 6 can be performed simultaneously with step 5.

Step 7 (see FIG. 8): An upper electrode 7 is provided between the upper protective film 5 and the separation layer 6.

The height of the upper electrode 7 is set so as to be equal to or slightly protrude from the upper surface of the upper protective film 5.
The material of the upper electrode 7 can be formed by overlapping a plurality of times. In the case where thick glass glaze glass is used as the material of the upper protective film 5 in the steps 5 to 7, the separation layer 6 is also made of the same thick glass glaze glass and the upper electrode 7
Is a thick film glaze-based conductive material having a firing temperature equal to or lower than the firing temperature of the upper protective film 5 so that the upper electrode 7 does not cover the entire surface of the separation layer 6. And On the other hand, when a resin-based paint is used as the material of the upper protective film 5, the separation layer 6 is also made of the same resin-based paint, and the upper electrode 7 is also made of a resin-based conductive paint.

Step 8: The original plate is successively divided along the vertical groove 1 and then along the horizontal groove w. The separation of the separation layer 6 by the division of the vertical groove 1 does not divide the upper layer electrode 7.

Step 9: A plating film 8 composed of nickel plating and solder plating (tin-lead) is formed on the upper electrode 7 to obtain a chip resistor 10.

In the above embodiment, as shown in FIG.
Since the upper and lower ends of the upper electrode 7 are arranged inside the lateral groove w,
Even if a plurality of chip resistors 10 are arranged side by side in contact with the divided surface of the lateral groove w, a short circuit between the resistors 10 is avoided, and the mounting area of the resistors 10 can be effectively utilized. On the other hand, the upper electrode 7 can be extended in the vertical direction while straddling the horizontal groove w. In this case, since the width of the upper electrode 7 over the horizontal groove w is narrow, the division of the horizontal groove w is easy, and
No burrs or chips that adversely affect the divided surface from the lateral groove w are generated.

FIG. 9 is a plan view of the chip resistor 20 obtained by the present manufacturing method, and FIG. 10 is a sectional view taken along the line BB 'of FIG. Parts common to the chip resistor 10 are denoted by the same reference numerals. The difference between the chip resistor 20 and the chip resistor 10 is that the upper protective film 15 is formed on the entire surface of the insulating substrate 1 except for the uncovered portion 17 ′ without providing the independent separating layer 6. And the uncovered portion 17 ′ is formed between the portion that straddles the vertical groove 1 and the uncovered portion 17 ′.
In addition, since it is set inside the horizontal groove w, the upper electrode 7 provided in the uncovered portion 17 'does not cover the horizontal groove w. Since the upper layer electrode 7 does not cover the lateral groove w, the chip resistor 20 can always avoid short circuit in the adjacent arrangement from the lateral groove dividing surface.

In the manufacturing process of the chip resistor 20, first, after the same processes as the above-described processes 1 to 4 for the chip resistor 10, as shown in FIG. formed on the entire surface of the insulating substrate 1 except for the pair of left and right uncovered portions 17 ′ inside w, and then the uncovered portions 17 ′
The upper electrode 7 is provided. Thereafter, steps 8 and 9 described above are performed.

[0029]

As described above, in the present manufacturing method,
By forming the separation layer along the first dividing groove,
The upper layer electrode having the ensured thickness is prevented from covering the first dividing groove, and it is possible to avoid burrs and chipping of the upper layer electrode at the time of dividing the original plate, and is required as a filletless type chip resistor. An occupied area required for the solder connection between the upper surface electrode and the land of the mounting board can be reliably secured, which contributes to further downsizing of the chip resistor.

In the present manufacturing method, in addition to having the advantages of the present manufacturing method, since the electrodes do not always contact the dividing surface of the second dividing groove, a plurality of chip resistors are arranged adjacent to the second dividing groove dividing surface. Even if they are arranged, a short circuit between the adjacent members can be avoided, and the adjacent space can be reduced to effectively use the mounting area.

[Brief description of the drawings]

FIG. 1 is a plan view showing a chip resistor obtained according to the present invention.

FIG. 2 is a sectional view taken along line A-A 'of FIG.

FIG. 3 is a plan view schematically showing a step 1 of the present invention.

FIG. 4 is a plan view schematically showing step 2 of the present invention.

FIG. 5 is a plan view schematically showing a step 3 of the present invention.

FIG. 6 is a plan view schematically showing step 4 of the present invention.

FIG. 7 is a plan view schematically showing steps 5 and 6 of the present invention.

FIG. 8 is a plan view schematically showing step 7 of the present invention.

FIG. 9 is a plan view showing another chip resistor obtained according to the present invention.

FIG. 10 is a sectional view taken along line B-B 'of FIG.

FIG. 11 is a plan view schematically showing another upper protective film forming step of the present invention.

[Description of Signs] 1 Insulating substrate 2 Lower electrode 3 Resistive film 3 'Trimming groove 4 Lower protective film 5, 15 Upper protective film 6 Separation layer 7 Upper electrode 8 Plating film 10, 20 Chip resistor 17' Uncovered portion

Claims (2)

[Claims] 1. A method for manufacturing a filletless type chip resistor in which an upper surface of an electrode is solder-bonded to a land of a wiring board, wherein a plurality of first division grooves and a plurality of second division grooves orthogonal to each other are provided. Arranging a pair of lower electrodes at both ends of the insulating substrate over the first division groove on an original plate for partitioning the insulating substrate; and arranging a resistive film communicating between the lower electrodes. A step of trimming the resistance film; a step of covering the resistance film with a protective film; and a separation layer extending relatively narrowly over the first division groove and extending along the first division groove. Forming an upper electrode between the protective film and the separation layer; dividing the original plate along the first and second division grooves; Step of forming a plating film on the upper electrode Method of manufacturing a chip resistor which comprises a. 2. A method of manufacturing a filletless type chip resistor in which an upper surface of an electrode is solder-bonded to a land of a wiring board, wherein a plurality of first and second divisional grooves are orthogonal to each other. A step of disposing a pair of lower electrodes at both ends of the insulating substrate over the first division groove on an original plate that partitions the insulating substrate; and a step of disposing a resistive film communicating between the lower electrodes. Trimming the resistive film; and forming a pair at both end portions of the insulating substrate, leaving an uncovered portion inside the first and second divisional grooves,
A step of covering the entire surface of the insulating substrate with a protective film; a step of arranging an upper layer electrode on the uncovered portion; and a step of dividing the original plate along the first and second division grooves. And forming a plating film on the upper electrode.