JP2000030902A - Chip type resistor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the chip size of a chip type resistor and, at the same time, to improve the accuracy of the chip size by providing a reference resistance section and a trimming section which is thinner in thickness than the reference resistance section in parallel in a resistor. SOLUTION: A resistor 2 provided with a reference resistance section 5 and a trimming section 6 which is thinner in thickness than the section 5 is formed against an insulating substrate 1 which is divided into a plurality of divisions by longitudinal and transversal splitting grooves. Then a conductive material which becomes the electrodes 3 of the resistor 2 is formed on the edge of each division facing the transversal splitting groove and the resistance produced between the electrodes 3 of the resistor 2 is measured. Thereafter, an L-shaped notch 16 is formed in the trimming section 6 with a laser beam so that the resistance of the resistor 2 may become a prescribed value. After forming the notch 16, an insulating protective film 4 is formed and chip parts are obtained by separating each division from another. Therefore, the fluctuation of the resistance of the resistor 2 caused by the stress impressed when the laser trimming is performed can be reduced without increasing the power of the laser trimming even when the thickness of the resistor 2 increases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip resistor realizing low resistance and uniform resistance, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, with the spread of computers and their peripheral devices and their high performance, electronic components such as resistors used for circuit boards have also been required to have high precision. In order to reduce the power, it is also required to reduce the resistance of the resistor.

[0003]

The thick-film resistor employed in the current chip-type resistor is manufactured through the steps of forming an electrode, forming a resistor, adjusting a resistance value, and forming a glass film sequentially. It is common. The realization range of the resistance value of the resistor depends on the resistor material used, the resistor film thickness, the distance between the electrodes, the electrode width, and the like. Use a material with low resistivity. 2. Increase the thickness of the resistor. 3. Reduce the distance between the electrodes. 4. Increase the width of the resistor and the electrode. Although it is possible to lower the resistance by such means as other materials, there is a limit even if the material has a small resistivity, and in the case of a resistor with a small chip size, there are great restrictions when changing the electrode arrangement However, in the means of reducing the resistance, it is difficult to reduce the distance between the electrodes. For example, the diffusion of the electrode (silver) into the resistor causes a problem that the temperature coefficient of resistance increases. In addition, if the width of the electrode is increased, not only the chip size is increased, but also the variation of the initial resistance value is increased. Also, even if a means for increasing the thickness of the resistor is selected, a strong power is required when adjusting the resistance value by, for example, laser trimming,
A problem that cannot be ignored in securing product quality, such as a variation in resistance value due to stress applied to the resistor due to the power, and a large trimming width, which easily causes pinholes in the glass film. Occurs.

The present invention has been made in view of the above circumstances, and has as its object to provide a highly accurate chip resistor having a small chip size and a method of manufacturing the same.

[0005]

In order to solve the above-mentioned problems, a chip-type resistor according to the present invention has a resistor, its electrodes, and a protective film covering the resistor on an insulating substrate. In the chip type resistor, the resistor is formed by arranging a reference resistance portion and a trimming portion thinner than the reference resistance portion in parallel. The resistor is
The resistor may be formed on at least one surface of the insulating substrate. In some cases, a resistor having another structure connected in parallel with the resistor may be formed on another surface.

Here, the reference resistance portion refers to a portion fixed so as to roughly determine the resistance value of the resistor, and the trimming portion refers to a portion provided for convenience during trimming. In general, a resistor having a high resistance value sets the resistor thin, so that there is no problem even if laser trimming is performed on any part of the resistor, and most of the resistors requiring the trimming portion are, This results in a resistor having a low resistance value. Therefore, the trimming portion is often thinner than the reference resistance portion, and the thickness of the reference resistance portion and the trimming portion are often different due to the difference in the number of constituent layers. Also, juxtaposition means that they are provided side by side literally, and may be separated from each other, or may be closely attached or integrated.

The method of manufacturing a chip-type resistor includes a resistor forming step of fixing a resistor in each of the plurality of insulating substrates divided through the vertical dividing grooves and the horizontal dividing grooves. An electrode forming step of fixing a conductive material serving as an electrode of a resistor formed in each section to an edge of each section facing the horizontal division groove, and an inspection for measuring a resistance value generated between the electrodes of each resistor. In the method of manufacturing a chip component, which includes a step and a dividing step of separating each section into a plurality of chip components, in the resistor forming step, a lower layer having a thickness suitable for trimming is formed on the insulating substrate. The method is characterized in that one step and a second step of superposing a resistance material as an upper layer on a part of the lower layer to give a predetermined resistance value to the resistor are performed.

Another chip type resistor is a chip type resistor in which a resistor, its electrodes, and a protective film covering the resistor are formed on an insulating substrate. In one of the above, a reference resistor is provided, and in the other, a trimming resistor thinner than the reference resistor is provided, and the electrodes of both resistors connect the reference resistor and the trimming resistor in parallel. To
One example is that electrodes formed on the front and back of the insulating substrate are electrically connected one-to-one.

The above-mentioned method of manufacturing a chip-type resistor includes a resistor forming step of fixing a resistor in each of the plurality of divided insulating substrates through the vertical dividing groove and the horizontal dividing groove. An electrode forming step of fixing a conductive material serving as an electrode of a resistor formed in the section to an edge of each section facing the horizontal division groove; and an inspection step of measuring a resistance value generated between the electrodes of each resistor. In the method of manufacturing a chip component through a dividing step of separating each of the sections into a plurality of chip components, in the resistor forming step, the reference resistor and the trimming resistor are formed by changing the front and back of the insulating substrate. In the electrode forming step in which the electrodes are formed, after forming a through hole that penetrates the front and back of the insulating substrate in the center of the horizontal dividing groove for one section, each of the front surface and the rear surface of the insulating substrate For it, characterized in that integrally formed two compartments electrodes continuous through the horizontal dividing groove.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a chip resistor according to the present invention will be described together with a method of manufacturing the same. FIG.
The manufacturing method according to the first and second embodiments shown in FIGS. 2 and 3 applies the reference resistance portion 5 or the reference resistance to the insulating substrate 1 made of alumina divided into a plurality of sections by the vertical division grooves 10 and the horizontal division grooves 11. A resistor 7 having a body 7 (hereinafter, referred to as a reference resistance portion, etc.) and a trimming portion 6 or a trimming resistor 8 (hereinafter, referred to as a trimming portion, etc.) thinner than the reference resistance portion, etc. A resistor forming step of fixing the electrodes in the respective sections; and forming an electrode for fixing a conductive material to be the electrodes of the resistors formed in the sections to the edges of the sections facing the horizontal division grooves. The process includes a process, an inspection process of measuring a resistance value generated between the electrodes of each resistor 2, and a dividing process of separating each of the sections 12 into a plurality of chip components (see FIG. 5).

When manufacturing the first embodiment, first,
As shown in FIG. 3A, a conductive material obtained by mixing silver, glass, and a binder resin to form a paste is printed on the insulating substrate 1 by a screen printing method. Printing and baking on the insulating substrate 1 at a high temperature. Here, the front and rear chip resistors separated by horizontal dividing grooves (divided grooves extending in the direction perpendicular to the direction in which the electrodes 3 and 3 formed at both ends of the resistor 2 are arranged) 11 are connected in series. Thus, the two electrodes 3, 3 are formed as a continuous integral body. Therefore, a phenomenon occurs in which the conductive material flows into the horizontal division groove 11 and extends in the horizontal direction through the horizontal division groove 11 due to a capillary phenomenon.

[0012] The lateral extension of the conductive material causes a problem of connecting the laterally adjacent resistors 2 in parallel, which causes a problem that the inspection step accompanying laser trimming cannot be performed. .
Therefore, in the operation of printing the conductive material to be the electrodes 3, the vertical division grooves (the electrodes 3 formed at both ends of the resistor 2) are used.
Care must be taken so that the electrodes 3 of the horizontally adjacent sections 12 do not come into contact with each other beyond the divided grooves 10 extending in the direction in which the rows 3 are arranged.

Next, as shown in FIGS.
The resistor 2 is formed in such a manner that a pair of electrodes 3 and 3 formed at both ends of the resistor 2 are connected. In the resistor forming step, a band shape (for example, 15 μm thickness) suitable for laser trimming is formed. , L (length) / W (width) ratio: 2) in the first step of forming the lower layer 13, and further on the lower layer 13 formed in the first step, a half of the lower layer 13 is formed. A second step of superposing and forming a band-shaped upper layer 15 having a width (for example, L / W ratio: 4).
Thickness (for example, 30 μm thickness) applied in accordance with the process
Is a reference resistance portion 5 which roughly determines the resistance value of the resistor 2, and a relatively thin portion subjected to only the first step is a trimming portion 6.

The resistance material is made by mixing an inorganic component such as ruthenium oxide, a binder made of glass powder, and an organic resin such as ethylcellulose into a paste.
Through a firing process at a high temperature of 0 ° C., the binder is burned off, and at the same time, the glass powder is melted and solidified again, whereby the ruthenium oxide of the resistance component is fixed on the alumina insulating substrate 1 and is fixed to 0.1 Ω. Is obtained.

In the resistor forming step, it is preferable that the upper layer 15 formed in the second step does not protrude from the region of the lower layer 13 formed in the first step. It is preferable that the upper layer 15 is formed in a place where the laser beam is not irradiated in the laser trimming step. In addition, in order to suppress that the silver of the conductive material that becomes the electrode 3 diffuses into the material of the resistor 2,
The order in which the resistor forming step and the electrode forming step are performed may be reversed. However, in that case, it is important to perform accurate positioning so that the resistor 2 and the electrode 3 are overlapped firmly.

Thereafter, the trimming portion 6 is irradiated with a laser beam, and an appropriate cut 16 is made in the trimming portion 6 so as to have a predetermined resistance value as shown in FIG.
At this time, it is desirable to use a method of cutting the trimming portion 6 into an L-shape as a measure for preventing a crack from being generated in the resistor 2 due to stress caused by the irradiation of the laser beam. On the surface of the resistor 2 after the trimming step, an insulating protective film 4 made of glass is further formed to be shielded from the outside air.

As shown in FIG. 5, the insulating substrate 1 made of alumina after the formation of the resistor 2 and the electrode 3 and the trimming of the resistor 2 and the formation of the protective film 4 are completed, as shown in FIG. End electrodes 17 which are divided along 11 and are integrated with the previously formed electrode 3 are collectively formed for a plurality of sections 12 connected side by side. Finally, the vertical dividing groove 10
Then, the surfaces of the electrodes 3 and 17 are plated as necessary to complete the chip resistor as a product.

The chip resistor formed as described above
A low resistance value can be secured by the reference resistance portion 5 of the resistor 2 formed thick through the first step and the second step, and the relatively thin film formed by the trimming portion 6 formed only by the first step is used. As a result, it is possible to make a sufficient cut 16 even with a laser beam having a relatively low power, and it is possible to reduce the stress applied to the resistor 2. And the chip resistor is also about 0.1Ω
I was able to obtain a small resistance value.

FIG. 2 shows that the reference resistor 7, the trimming resistor 8 thinner than the reference resistor 7, and the protective film 4 are laminated on the front and back surfaces of the insulating substrate, respectively. A front-back integrated electrode 9 connected to the two resistors 7 and 8 and connecting the two resistors 7 and 8 in parallel is provided at both ends of the two resistors 7 and 8 formed on the front surface and the rear surface, respectively.
This is a second embodiment in which is formed.

In forming the electrode according to the second embodiment, the insulating substrate 1 is located at the center of the horizontal division groove 11 for one section.
Are formed through the front and back surfaces of the insulating substrate 1, and the front surface and the back surface of the insulating substrate 1 are connected to each other through the horizontal dividing groove 11 in two sections of the electrode 9 a and the electrode 9 b.
Is integrally formed. It is desirable that the diameter of the through hole 14 is larger than the width of the horizontal dividing groove 11, but it is necessary that the diameter of the through hole 14 does not deviate from the area where the electrode 9 is to be formed.

When the electrodes 9 are formed under such conditions, when the conductive material to be the electrodes 9a or 9b is printed,
The inside of the through hole 14 is filled with a conductive material, and by printing from both the front and back of the insulating substrate 1,
The electrodes 9a, 9a and the electrodes 9b, 9b formed on both sides of the insulating substrate 1 are connected via through holes 14, and a pair of front and back resistors 2 formed in the section 12 are connected in parallel. . When printing the conductive material to be the electrode 9, in addition to the points described in the first embodiment, the conductive material that has passed through the through-hole 14 does not scatter and adhere on the back surface side, nor does whiskers occur. To be considered.
The silver insulating substrate 1 contained in the conductive material to be the electrode 9
It is desirable that both surfaces be fired at the same time in order to suppress diffusion to the surface and to reduce the number of steps. If the center of the through hole 14 is set at the center in the width direction of the horizontal dividing groove 11, the notch portions 18 of the same size are formed in both vertically adjacent sections 12, and are made of a conductive material of the same thickness. Front and back conductive portions 19 are formed on the end surfaces of both sections 12.

As in the first embodiment, the resistor 2 has a band shape (for example, L / W ratio: 2) connecting the pair of electrodes 9 formed on each surface. Is formed.
In the present embodiment, the trimming resistor 8 formed on the surface is the same as the trimming portion 6 of the first embodiment.
Is equivalent to Therefore, in consideration of the subsequent laser trimming process, it is necessary to set the thickness to a relatively small thickness (for example, a thickness of 15 μm) that does not require a laser beam having a large power.

On the other hand, the reference resistor 7 formed on the back surface
In consideration of the target resistance value and the amount of adjustment of the resistance value by the trimming resistor 8, the resistance value of the chip resistor is substantially determined by the resistance value of the reference resistor 7 formed on the back surface. Set the wall thickness. The resistance material printed on both sides may be fired simultaneously, but the thickness of the back surface becomes thicker than the front surface, so it is necessary to pay attention to insufficient firing of the resistance material printed on the back surface. Also in this embodiment, the order of forming the resistors 7 and 8 and forming the electrodes 9b and 9a may be reversed. In this case, the forming of the resistors 7 and 8 and the electrodes 9b and 9a may be performed. And precise alignment is required to ensure that they overlap.

Laser trimming is performed on the trimming resistor 8 formed exclusively on the surface of the insulating substrate 1 as described above.
The cutting is performed by making a cut 20 with a laser beam, and the reference resistor 7 formed on the back surface is not irradiated with the laser beam. After the laser trimming is completed, insulating protection films 4 and 4 made of glass or the like are formed so as to cover the resistors 7 and 8 on each surface. The baking of the protective film 4 may be performed on one surface at a time or on both surfaces at the same time. However, the baking of the protective film 4 may cause a drift in the resistance value after trimming. In consideration of the above, it is necessary to bake the protective film 4. Thereafter, similar to the first embodiment, completion is achieved by performing division or plating.

In the chip type resistor according to the second embodiment, a low resistance value can be ensured by the reference resistor 7 formed relatively thick on the back surface, and the chip resistor is formed thin on the front surface. The trimming resistor 8 can be cut sufficiently by a laser beam having a relatively low power, not only to reduce the stress applied to the resistor formed on the front surface but also to reduce the stress applied to the resistor formed on the back surface. Can be trimmed and manufactured without applying any stress. And the chip type resistor was able to obtain a small resistance value of about 0.05Ω.

[0026]

As described above, if the chip type resistor according to the present invention is used, even if the means for increasing the thickness of the resistor is selected, the resistance value is adjusted by, for example, laser trimming due to the presence of the trimming portion. This eliminates the need for strong power when performing the process, and as a result, the stress during laser trimming does not increase the variation in the resistance value of the resistor. No holes are generated. Moreover, the resistance value, which requires the technique of reducing the distance between the electrodes, becomes lower,
An increase in the temperature coefficient of resistance due to the reduction in resistance is also suppressed to some extent, and a chip resistor with a small chip size and high accuracy and low resistance can be provided.

[Brief description of the drawings]

FIGS. 1 (a), 1 (b) and 1 (c) are a plan view, a side view and a front view showing an example of a chip resistor according to the present invention.

FIG. 2 is a perspective view showing an example of a chip resistor according to the present invention.

3 (a), (b), (c), (d), and (e) are main part process diagrams showing an example of a method of manufacturing a chip resistor according to the present invention.

4 (a), (b), (c), (d), and (e) are main part process diagrams showing an example of a method of manufacturing a chip resistor according to the present invention.

FIG. 5 is a process chart showing an example of a method for manufacturing a general chip-type resistor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate, 2 resistor, 3 electrode, 4 protective film 5 Reference resistor part, 6 trimming part 7 Reference resistor, 8 trimming resistor 9 electrode, 9a, 9b electrode 10 Vertical division groove 11 Horizontal division groove 12 Section 13 Lower part Layer 14 Through hole

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masanori Mizushima 30th Oyama-cho, Kamishinkawa-gun, Toyama Fate term in Tateyama Kagaku Kogyo Co., Ltd. 5E032 BA04 BA07 CA02 CB03 CC03 CC14 CC16 TA14 TB02 5E033 AA18 AA27 BB02 BC01 BD03 BE01 BF05 BG02 BG03 BH02 BH03

Claims (5)

[Claims] 1. A chip type resistor in which a resistor (2), its electrode (3), and a protective film (4) covering the resistor (2) are formed on an insulating substrate (1). The resistor (2) includes a reference resistance section (5) and the reference resistance section (5).
A chip type resistor comprising a thinner trimming portion (6) arranged side by side. 2. The resistance body (2) is constituted by a juxtaposition of a reference resistance part (5) and a trimming part (6) whose wall thickness is varied by a difference in the number of constituent layers. 1
The described chip-type resistor. 3. A chip-type resistor in which a resistor (2), its electrode (3), and a protective film (4) covering the resistor (2) are formed on an insulating substrate (1). A reference resistor (7) is provided on one of the front surface and the back surface of the substrate (1), and the reference resistor (7) is provided on the other.
A thinner trimming resistor (8) is provided, and the electrodes (9) of both resistors (7, 8) are insulated to connect the reference resistor (7) and the trimming resistor (8) in parallel. A chip-type resistor, wherein electrodes (9a, 9b) formed on the front and back of a substrate (1) are electrically connected one to one. 4. A vertical dividing groove (10) and a horizontal dividing groove (11).
A resistor forming step of fixing the resistor (2) in each of the sections (12) with respect to the insulating substrate (1) partitioned into a plurality of sections through the step (a), and a resistor formed in each section (12). An electrode forming step of fixing a conductive material to be the electrode (3) of (2) to an edge of each section (12) facing the horizontal division groove (11); and an electrode (3, 3) of each resistor (2). In the method for manufacturing a chip component, which includes an inspection process of measuring a resistance value generated between the two components and a dividing process of separating each of the sections (12) into a plurality of chip components, the method includes the steps of: 1) forming a lower layer (13) having a thickness suitable for trimming on the first
Process and part of the lower layer (13) to the upper layer (1).
5) A method of manufacturing a chip-type resistor, comprising performing a second step of giving a predetermined resistance value to the resistor (2) by polymerizing a barrel resistance material. 5. A vertical dividing groove (10) and a horizontal dividing groove (11).
A resistor forming step of fixing the resistor (2) in each of the sections (12) with respect to the insulating substrate (1) partitioned into a plurality of sections through the step (a), and a resistor formed in each section (12). An electrode forming step of fixing a conductive material to be the electrode (3) of (2) to the edge of each section (12) facing the horizontal division groove (11); and an electrode (9, 9) of each resistor (2). In the method for manufacturing a chip component, which includes an inspection process of measuring a resistance value generated between the two components and a dividing process of separating each of the sections (12) into a plurality of chip components, the method includes the steps of: In the electrode forming step in which the reference resistor (7) and the trimming resistor (8) are formed with the front and back surfaces different from each other and the electrodes (9a, 9b) are formed, horizontal division of one section is performed. A slot penetrating the front and back of the insulating substrate (1) at the center of the groove (11). After the formation of the through holes (14), the electrodes (9a (9a) (9a (9)) are continuously formed on the front and back surfaces of the insulating substrate (1) through the horizontal division grooves (11).
b) and 9a (9b)) are integrally formed.