JP2928015B2 - Multiple resistance element structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a multiple resistor element structure in a chip multiple resistor, a network resistor, a hybrid IC and the like.

[0002]

2. Description of the Related Art Generally, a multiple resistance element is one in which a large number of resistance elements are arranged at regular intervals, and is used for a chip multiple resistance element, a network resistor, a hybrid IC, and the like. For example, a chip multiple resistor has a structure as shown in FIG. 6 (an external perspective view) and FIG. 7 (a cross-sectional view along line AA in FIG. 6). This resistor is formed by connecting two resistive elements each composed of a pair of electrodes 11 and a resistor 15, for example, an alumina substrate 10, and two pairs arranged at regular intervals on both sides of the substrate 10 opposite to each other. Electrode 11, a resistor 15 connecting each pair of electrodes 11, a resistor 15 and the electrode 1
And a protective sheath 19 that covers a part of the cover 1. Electrode 11
Are a pair of internal electrodes 12a provided on the upper surface of the substrate 10,
12b, and a side electrode 13 continuous with the internal electrodes 12a and 12b and provided on the side of the substrate 10.
a and 13b. Further, the protective exterior 19 includes an undercoat glass 17 and an overcoat glass 18.

[0003]

In the above resistor, the internal electrodes 12a and 12b and the resistor 15
Are formed independently for each resistance element, and there is a part where nothing is formed between the resistance elements.
A step (a height difference) occurs between the resistor 15 and the surface of the resistor 15.
Since the protective case 19 is common to both elements, a concave portion corresponding to the step is formed in the protective case 19, and the surface smoothness of the protective case 19 in the completed product is impaired (see FIG. 7). As shown in FIG. 8, such a resistor is usually mounted on a substrate by suctioning with air 41 in a suction nozzle 40 of a mounting machine, but if the surface of the resistor is not flat, the tip of the suction nozzle 40 A gap is generated between the surface and the surface of the protective case 19. For this reason, suction is not performed, sufficient suction is not performed, and the mounting rate on the substrate is deteriorated.

[0004] This applies not only to multiple chip resistors, but also to network resistors, hybrid ICs, and the like. Therefore, an object of the present invention is to provide a multiple resistance element structure that can improve the surface smoothness of various products in which a large number of resistance elements are arranged.

[0005]

In order to achieve the above-mentioned object, a multiple resistance element structure according to the present invention comprises, in a conventional structure, a resistance element comprising a pair of electrodes and a resistor, and A filling layer for filling a step between the resistor and the substrate surface is provided between the first and second resistors. Since the compensation layer provided between the resistance elements substantially eliminates irregularities on the surface of the substrate, the surface of the protective exterior also becomes smooth. Therefore, when the air is sucked by the suction nozzle at the time of mounting on the substrate, no air leakage occurs, and the suction property of the nozzle is improved.

It is sufficient that the filling layer can fill the step between the resistor and the substrate surface. However, if the filling material is formed so as to overlap with the resistor and the electrode (internal electrode), the surface smoothness effect may be weakened. Since there is a possibility that a trouble occurs in the trimming process of the resistor, it is necessary to pay attention so that the filling layer does not overlap the resistor and the internal electrode as much as possible. For this reason, a glass paste having a relatively high viscosity is suitable as a filler in the multiple chip resistor.
In the case of a network resistor or hybrid IC,
It is not necessary to use a filler as a glass paste, and a resin or the like can be used instead. By providing the supplementary layer and smoothing the surface of the network resistor or the hybrid IC, a mold type mounting machine can be used, which is convenient.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a multiple resistance element structure according to the present invention will be described based on embodiments. FIG. 1 is a sectional view of a main part of a chip multiple resistor as an example. The appearance of this resistor is not different from the general one shown in FIG. 6, and the internal structure is different from the conventional one. Therefore, the same components are denoted by the same reference numerals.
This resistor includes, as described above, the alumina substrate 10,
It includes a pair of electrodes 11 provided on opposite sides of the substrate 10, a resistor 15 for connecting the electrodes 11, and a protective sheath 19 covering a part of the resistor 15 and the electrodes 11. The electrode 11 includes an internal electrode 12a provided on the upper surface of the substrate 10,
12b and side electrodes 13a and 13b which are electrically connected to the internal electrodes 12a and 12b, respectively.
Is composed of an undercoat glass 17 and an overcoat glass 18.

[0008] The filling layer 16 which is a feature of the present invention is provided between the resistive elements composed of the internal electrodes 12 a and 12 b and the resistor 15, and has a function of filling a step between the resistor 15 and the surface of the substrate 10. Have. By providing the supplementary layer 16, there is almost no unevenness on the surface of the substrate 10.
Has a flat surface as shown in FIG. As a result, when this resistor is mounted on the substrate, even if the resistor is sucked by the air 41 of the suction nozzle 40 of the mounting machine in FIG. 2, the air 41 does not leak from the gap because the surface is smooth. In addition, the suction property of the nozzle is improved.

Next, the production of the chip multiple resistor will be briefly described. First, in FIG. 3A, the breaking slits 2 previously formed on the alumina substrate 10 vertically and horizontally are formed.
The internal electrode material is printed and fired on the substrate 10 in a pattern as shown in the figure along the lines 0 and 21 to form a pair of internal electrodes 12a and 12b at regular intervals, and between the electrodes 12a and 12b. , A circular hole 22 is formed.

Next, as shown in FIG. 1B, a resistor paste is printed so as to overlap with each pair of internal electrodes 12a and 12b, and baked to form a resistor 15 for connecting the internal electrodes 12a and 12b. To form Thereby, the internal electrode 1
A resistance element composed of 2a, 12b and the resistor 15 is configured. Thereafter, a glass paste is printed and baked between the two resistive elements to form a supplementary layer 16 (see (c) of FIG. 3). Of course,
The supplementary layer 16 is for filling a step between the resistor 15 and the surface of the substrate 10, and forms the internal electrodes 12 a, 12 a at the time of formation.
b and the resistor 15.

Then, in FIG. 4D, a glass paste is printed and fired so as to cover a part of the internal electrodes 12a and 12b, the resistor 15 and the supplementary layer 16, and the undercoat glass 17 (in FIG. (Dotted line). Subsequently, in order to set the resistance value of each resistor 15 to a predetermined value, trimming is performed by, for example, irradiating a laser beam to the undercoat glass 17.
It is performed from above (see (e) of FIG. 3). By this laser trimming, grooves 25 and 25 ′ are formed in the resistor 15 and the undercoat glass 17.

Next, a glass paste is further printed and baked on the undercoat glass 17 to form an overcoat glass 18, and a protective sheath 19 made of the glass 17, 18 is formed (see (f) in the figure). Thereafter, as shown in FIG. 5G, the slits 20 and 21 formed in the substrate 10 are formed.
From the side electrodes 1 connected to the internal electrodes 12a and 12b for each resistance element.
3a and 13b are formed and finished as a product.

Although the above embodiment relates to a multiple chip resistor, the same effect can be obtained by providing a supplementary layer in a network resistor or a hybrid IC.

[0014]

As described above, in the multiple resistance element structure of the present invention, a complementary layer for filling the step between the resistor and the substrate surface is provided between each resistance element. The surface of a product such as a network resistor becomes smooth, and the nozzle suction of a mounting machine used when mounting the product on a substrate is improved. For this reason, the mounting rate on the substrate is increased, and the defective rate of components is reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a multiple chip resistor according to an embodiment of the present invention.

FIG. 2 is a diagram when the resistor shown in FIG. 1 is sucked by a suction nozzle of a mounting machine.

FIG. 3 is a first to third process charts for manufacturing the resistor shown in FIG. 1;

FIG. 4 is a fourth to sixth process charts for manufacturing the resistor shown in FIG. 1;

FIG. 5 is a seventh process chart for manufacturing the resistor shown in FIG. 1;

FIG. 6 is an external perspective view of a general chip multiple resistor.

FIG. 7 is a sectional view taken along line AA in FIG. 6;

FIG. 8 is a diagram when the resistor shown in FIG. 7 is sucked by a suction nozzle of a mounting machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Alumina substrate 11 Electrode 12a, 12b Internal electrode 13a, 13b Side electrode 15 Resistor 16 Filler layer 17 Undercoat glass 18 Overcoat glass 19 Protective exterior

Claims (1)

(57) [Claims] 1. A multi-layer structure comprising: a pair of electrodes arranged side by side at regular intervals on a substrate; a resistor for connecting each pair of electrodes; and a protective sheath covering a part of the resistor and the electrodes. In the continuous resistance element structure, a supplementary layer for filling a step between the resistor and the substrate surface is provided between the resistor and the resistor formed by each pair of electrodes and the resistor. Multiple resistance element structure.