JP2007048784A - Chip resistor and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chip resistor of low resistance which has a simple structure, can mount a resistor toward a circuit board-side, has sufficient detergency after mounting, and cannot easily be influenced by heat due to heat generation of the resistor. <P>SOLUTION: A pair of surface electrodes 14 are formed on a surface of an insulating substrate 12, and resistors 16 and 17 are arranged between surface electrodes 14. Support projections 30 which project rather than the surface side of the resistor 17 are formed on the surface electrodes 14, and stably support the insulating substrate 12 on an upper part on a surface of a circuit board 34. The support projections 30 are formed by laminating projections 18 formed of insulating materials or conduction materials, an electrode material or a resistor material. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a chip resistor that is surface-mounted on the surface of a circuit board, and particularly to a low-resistance chip resistor and a method for manufacturing the same.

  Conventionally, a thick film chip resistor, which is generally formed by printing and firing a resistor material on the surface of an insulating substrate, has a protective layer on the surface of the resistor that is higher than the electrode height of the terminal portion, and is mounted on a circuit board. Sometimes it is surface mounted with the resistor on top.

  Further, as disclosed in Patent Document 1, the chip resistor is not tilted even when the resistor is mounted on the circuit board side by reducing the step between the protective layer of the resistor and the electrode surface. Some chip resistors are also available.

Furthermore, in the low resistance chip resistor, as disclosed in Patent Document 2, the plating layer is formed thick so that the height of the electrode surface is slightly higher than the surface of the protective layer of the resistor, There has also been proposed a resistor in which the resistor is not in contact with the circuit board surface even when the resistor is mounted facing the circuit board surface. As a result, the influence of the resistance of the electrode portion is suppressed, and the variation of the resistance value of the entire element is reduced. In particular, in a surface-mount type chip resistor, a chip resistor having a super resistance of 100 mΩ or less is increasing in demand for a high-precision and low temperature coefficient (TCR), and suppresses electrode resistance. Therefore, it is required to mount the resistor with the circuit board side.
JP-A-10-199702 JP 2003-45702 A

  However, in the case of Patent Document 1, the protective layer of the resistor is in contact with the circuit board, and in the case of a low resistance element in which a large current flows, the temperature of the element surface becomes high, so the circuit board is burned. There was a risk of burning.

  Further, in the case of Patent Document 2, the protective layer of the resistor is slightly separated from the surface of the circuit board, but a gap is formed, and the circuit board may be burned due to heat radiation from the resistor. In addition, there is a problem that flux used for soldering enters the space between the circuit board and the chip resistor and is not easily removed even after cleaning after soldering.

  The present invention has been made in view of the above-described conventional technology, and can be mounted with a simple configuration with the resistor facing the circuit board, has good cleanability after mounting, and heat generated by the resistor. An object of the present invention is to provide a low-resistance chip resistor that is not easily affected and a manufacturing method thereof.

  The present invention provides a chip resistor in which a pair of surface electrodes are formed on the surface of an insulating substrate, and a resistor is provided between the surface electrodes, and protrudes from the surface side of the resistor so as to be on the surface electrode. The chip resistor is formed and provided with a support protrusion that stably supports the insulating substrate above the circuit board surface.

  The support protrusion is formed of a convex portion formed of an insulating material or a conductive material. Alternatively, the support protrusion may be formed by laminating a plurality of electrode materials or by laminating the resistor on the surface electrode.

  The present invention also provides a resistor and a surface electrode connected to both ends of the resistor on the surface of the insulating substrate, and the insulator is projected on the pair of surface electrodes from the protective layer of the resistor. Alternatively, it is a method for manufacturing a chip resistor, in which a conductive paste is applied to form a convex portion, and a convex protrusion is formed by this convex portion to stably support the chip resistor on the surface of the circuit board.

  Further, the present invention forms a resistor and a surface electrode laminated on both ends of the resistor on the surface of the insulating substrate, laminates a plurality of layers of the resistor and electrode material, protrudes from the protective layer of the resistor, and This is a method for manufacturing a chip resistor in which a support protrusion for stably supporting the chip resistor on the surface of the circuit board is formed.

  The chip resistor of the present invention can be stably surface-mounted on the circuit board, and can be sufficiently spaced from the circuit board side in a state where the resistor is mounted facing the circuit board side. It is easy to clean and is not easily affected by the heat generated by the resistor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 and 2 show a first embodiment of a chip resistor according to the present invention. As shown in FIG. 1, a chip resistor 10 of this embodiment has an Ag-- A front electrode 14 and a back electrode 15 are formed as primary electrodes obtained by firing a metal glaze paste such as Pd or Ag—Pt. Between the surface electrodes 14, resistors 16 and 17 obtained by baking a resistor paste such as ruthenium oxide or Ag—Pd are formed in two layers.

  Furthermore, the convex part 18 formed by apply | coating and baking glass paste, the metal glaze paste for electrodes, etc. on the surface of a pair of surface electrode 14 is formed. The protrusion 18 is formed so as to protrude from a protective layer 24 described later, and a support protrusion 30 protruding from the protection layer 24 is formed by the protrusion 18 and the plating layer 28. The protrusions 18 are formed in a straight line whose upper end surface is parallel to the surface of the insulating substrate 12, and the chip resistor 10 is stably supported by the pair of protrusions 18.

  A secondary electrode 20 is formed of the same material as that of the surface electrode 14 on the surface of the convex portion 18 and the surface electrode 14. Further, a thin glass coat 22 made of lead borosilicate glass or the like is formed on the surface of the resistor 17, and a protective layer 24 that is applied and baked in the same manner as the glass coat 22 is formed on the surface.

  End electrodes 26 made of conductive paste or the like are formed on both end surfaces of the insulating substrate 12 and the side surfaces of the protrusions 18. And the plating layer 28 by Ni plating as a protective layer, Sn plating, etc. of the outer side is formed in the surface of the end surface electrode 26 and the secondary electrode 20. As shown in FIG.

  Next, a manufacturing method of the chip resistor 10 of this embodiment will be described with reference to FIG. As shown in FIG. 2 (A), the chip resistor 10 of this embodiment is divided into an alumina dividing substrate 32 for dividing a plurality of insulating substrates 12 later and a front electrode 14 and a back electrode 15. A plurality of rows of metal glaze pastes are printed and fired at a temperature of about 850 ° C. And between each surface electrode 14, as shown in FIG.2 (B), the resistor paste which forms the resistor 16 is printed, and it bakes at the temperature of about 850 degreeC. Similarly, as shown in FIG. 2C, a resistor paste for forming the resistor 17 is printed and baked at a temperature of about 850 ° C.

  Next, as shown in FIG. 2D, glass bumps, electrode conductive paste, or the like is applied to the surfaces of the pair of surface electrodes 14 to form convex portions 18 and fired. The convex portion 18 is applied once or a plurality of times so as to protrude from the protective layer 24 to be formed later, is formed to a height of about 50 to 100 μm, and is baked at a temperature of about 850 ° C. Further, as shown in FIG. 2E, a metal glaze paste or the like similar to that of the surface electrode 14 is applied to the surface of the convex portion 18 and the surface electrode 14, and the secondary electrode 20 is baked at a temperature of about 850 ° C. Form.

  Next, as shown in FIG. 2F, a glass paste such as lead borosilicate glass is applied to the surface of the resistor 17 and baked at about 620 ° C. to form a thin glass coat 22. Thereafter, the resistors 16 and 17 are laser trimmed to adjust the resistance value.

  Further, as shown in FIG. 2G, a material such as a glass paste that forms the protective layer 24 is applied to the glass coat 22. Then, a single dividing substrate 32 is primarily divided in parallel with the alignment direction of the surface electrode 14 at the ends of the surface electrode 14 and the convex portion 18 on both sides of the resistor 16, and The end surface of the insulating substrate 12 is exposed. Next, as shown in FIG. 2 (H), a conductive paste such as a metal glaze paste for the end face electrode 26 is applied to the end face of the insulating substrate 12 and the substrate end face side of the secondary electrode 20 and the back electrode 15. The protective layer 24 and the end face electrode 26 are baked at about the same temperature.

  Subsequently, the primary divided insulating substrate 12 is further divided into chips in the direction orthogonal to the primary division to form a chip. As shown in FIG. 2I, the secondary electrode 20 and the back electrode 15 are formed. The plated layer 28 is formed by applying Ni plating and Sn plating to the end face electrode 26.

  According to the chip resistor 10 of this embodiment, the support protrusions 30 protruding from the protective layer 24 are formed at the both ends of the substrate 12 by the protrusions 18 protruding from the protective layer 24 of the resistors 16 and 17. 10 at both ends. As a result, the resistor 16 of the chip resistor 10 can be stably surface-mounted toward the land 36 side of the circuit board 34, a sufficient space is formed between the circuit board 34 and the protective layer 24, and heat dissipation is good. In addition, it is possible to reliably clean the flux during soldering. In this embodiment, the resistors 16 and 17 may be one layer of the resistors 16 and 17 according to a required resistance value.

  Next, a chip electronic component according to a second embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the chip resistor 38 of this embodiment, the resistors 16 and 17 of the first embodiment are extended and laminated on the surface electrode 14 and the secondary electrode 20, and the protrusion 18 is provided thereon, and the support protrusion 30. Is formed.

  In the manufacturing method of the chip resistor 38 of this embodiment, as shown in FIG. 3A, first, the resistor 16 is formed on the entire surface of the dividing substrate 32, and the metal glaze paste of the back electrode 15 is formed on the back surface. Are printed in multiple rows and fired at a temperature of about 850 ° C. Then, as shown in FIG. 3B, a plurality of rows of the metal glaze paste of the surface electrode 14 as the primary electrode are printed on the surface of the resistor 16 and fired at a temperature of about 850 ° C. Next, as shown in FIG. 3C, a resistor paste of the second-layer resistor 17 is printed between the surface electrodes 14 and on the surface thereof, and baked at a temperature of about 850 ° C.

  Next, as shown in FIG. 3D, a glass paste, a conductive paste for electrodes, or the like is applied to form the convex portion 18 and baked. The convex portion 18 is applied once or a plurality of times so as to be the same as or protruding from the protective layer 24 to be formed later, formed to a height of, for example, about 50 μm, and baked at a temperature of about 850 ° C. Then, as shown in FIG. 3E, the conductive paste of the secondary electrode 20 is printed at a position facing the surface electrode 14 of the resistor 17 so as to cover the convex portion 18 and fired at a temperature of about 850 ° C.

  Next, as shown in FIG. 3F, a glass paste is applied to the surface of the resistor 17 and baked at about 620 ° C. to form a thin glass coat 22. Thereafter, the resistors 16 and 17 are laser trimmed to adjust the resistance value.

  Further, as shown in FIG. 3G, a material such as a glass paste that forms the protective layer 24 is applied to the glass coat 22. Then, a single dividing substrate 32 is primarily divided at the ends of the surface electrode 14 on both sides of the resistor 16 in parallel with the alignment direction of the surface electrode 14, and the insulating substrate 12 at the end of the surface electrode 14 is divided. Expose end face. Next, as shown in FIG. 3H, a conductive paste such as a metal glaze paste for the end face electrode 26 is applied to the end face of the insulating substrate 12 and the end face sides of the secondary electrode 20 and the back electrode 15 to protect it. The layer 24 and the end face electrode 26 are simultaneously fired at about 620 ° C.

  Subsequently, the primary divided insulating substrate 12 is further divided into chips in the direction perpendicular to the primary division to form a chip. As shown in FIG. 3I, the secondary electrode 20 and the back electrode 15 are formed. The plated layer 28 is formed by applying Ni plating and Sn plating to the end face electrode 26.

  According to the chip resistor 38 of this embodiment, the resistors 16 and 17 extend at both ends of the substrate 12, and the convex portion 18, the surface electrode 14, and the secondary electrode 20 are formed. A protruding support protrusion 30 is formed. Thereby, the effect similar to the said embodiment can be acquired. Also in this embodiment, the resistors 16 and 17 may be either one layer according to a required resistance value.

  Next, a chip electronic component according to a third embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. The chip resistor 40 of this embodiment is formed by forming a single-layer resistor 16 so as to be laminated on the surface electrode 14 and forming a convex portion 18 thereon.

  In the manufacturing method of the chip resistor 40 of this embodiment, as shown in FIG. 4A, first, a plurality of rows of metal glaze pastes of the front electrode 14 and the back electrode 15 as primary electrodes are formed on the surface of the dividing substrate 32. Print and fire at a temperature of about 850 ° C. Next, as shown in FIG. 4B, between the surface electrodes 14 and on the surface thereof, a resistor paste for forming the resistor 16 is printed on one side and fired at a temperature of about 850 ° C.

  Next, as shown in FIG. 4C, a glass paste, a conductive paste for electrodes, or the like is applied to form the projections 18 and fired. The convex portion 18 is applied once or a plurality of times so as to be the same as or protruding from the protective layer 24 to be formed later, formed to a height of, for example, about 50 μm, and baked at a temperature of about 850 ° C.

  Next, as shown in FIG. 4D, the conductive paste of the secondary electrode 20 is printed at a position facing the surface electrode 14 of the resistor 16 on and around the surface of the convex portion 18 and is about 850 ° C. Firing at a temperature of Then, as shown in FIG. 4E, a glass paste is applied to the surface of the resistor 16 and baked at about 620 ° C. to form a thin glass coat 22. Thereafter, the resistor 16 is laser trimmed to adjust the resistance value.

  Further, as shown in FIG. 4F, a material such as a glass paste that forms the protective layer 24 is applied to the glass coat 22. Then, a single dividing substrate 32 is primarily divided at the ends of the surface electrode 14 on both sides of the resistor 16 in parallel with the alignment direction of the surface electrode 14, and the insulating substrate 12 at the end of the surface electrode 14 is divided. Expose end face. Next, as shown in FIG. 4G, a conductive paste such as a metal glaze paste is applied to the end face of the insulating substrate 12, the secondary electrode 20, and the back face electrode 15, and the protective layer 24 and the end face electrode 26 are set to 620 ° C. Bake at the same time.

  Subsequently, the primary divided insulating substrate 12 is further divided into chips in the direction orthogonal to the primary division to form a chip. As shown in FIG. 4H, the secondary electrode 20 and the back electrode 15 are formed. The plated layer 28 is formed by applying Ni plating and Sn plating to the end face electrode 26.

  According to the chip resistor 40 of this embodiment, the resistor 16 extends at both ends of the substrate 12, the surface electrode 14 and the secondary electrode 20 are formed, and the support protrusion protruding from the protective layer 24 by the protrusion 18. 30 is formed. Thereby, the effect similar to the said embodiment can be acquired. Also in this embodiment, the resistor 16 may have two layers according to a required resistance value.

  Next, a chip electronic component according to a fourth embodiment of the present invention will be described with reference to FIGS. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. The chip resistor 42 of this embodiment has a structure in which the end face electrode is omitted.

  A method for manufacturing the chip resistor 42 of this embodiment will be described with reference to FIG. As shown in FIG. 5A, the chip resistor 42 of this embodiment prints a plurality of rows of the metal glaze paste of the surface electrode 14 on the dividing substrate 32 and fires it at a temperature of about 850 ° C. And between each surface electrode 14, as shown in FIG.5 (B), the resistor paste which forms the resistor 16 is printed, and it bakes at the temperature of about 850 degreeC. Similarly, as shown in FIG. 5C, a resistor paste for forming the resistor 17 is printed and baked at a temperature of about 850 ° C.

  Next, as shown in FIG. 5D, glass bumps, conductive paste of electrodes, or the like is applied to the surfaces of the pair of surface electrodes 14 to form convex portions 18 and fired. Further, as shown in FIG. 5E, a metal glaze paste or the like similar to that of the surface electrode 14 is applied to the surface of the convex portion 18 and the surface electrode 14, and the secondary electrode 20 is baked at a temperature of about 850 ° C. Form.

  Next, as shown in FIG. 5F, a glass paste such as lead borosilicate glass is applied to the surface of the resistor 17 and baked at about 620 ° C. to form a thin glass coat 22. Thereafter, the resistors 16 and 17 are laser trimmed to adjust the resistance value. Further, as shown in FIG. 5G, a material such as a glass paste for forming the protective layer 24 is applied on the glass coat 22 and fired at about 620 ° C.

  Then, the single dividing substrate 32 is primarily divided in parallel with the alignment direction of the surface electrodes 14 at the ends of the surface electrodes 14 and the convex portions 18 on both sides of the resistor 16. Subsequently, the primary divided insulating substrate 12 is further divided into chips in the direction orthogonal to the primary division to form chips, and the secondary electrode 20 is plated with Ni as shown in FIG. , Sn plating is performed to form the plating layer 28.

  According to the chip resistor 42 of this embodiment, in addition to the same effects as those of the above embodiment, as shown in FIG. 6, the land 36 of the circuit board 34 can be reduced, and the mounting area can be reduced. . Further, the chip resistor of this embodiment may be one in which a resistor is formed on the entire surface of the substrate as in the second and third embodiments, and the same effect can be obtained by omitting the end face electrode. Furthermore, the resistor may have a single-layer or multi-layer structure.

  The chip resistor and the manufacturing method thereof according to the present invention are not limited to the above-described embodiment, and the upper end of the support protrusion only needs to have a shape that can stably support the chip resistor, and has a certain surface. If it is good. Moreover, the kind of a resistor or an electrode is not ask | required.

It is a longitudinal cross-sectional view which shows the mounting state of the chip resistor of 1st embodiment of this invention. It is a longitudinal cross-sectional view which shows the manufacturing process of the chip resistor of 1st embodiment of this invention. It is a longitudinal cross-sectional view which shows the manufacturing process of the chip resistor of 2nd embodiment of this invention. It is a longitudinal cross-sectional view which shows the manufacturing process of the chip resistor of 3rd embodiment of this invention. It is a longitudinal cross-sectional view which shows the manufacturing process of the chip resistor of 4th embodiment of this invention. It is a longitudinal cross-sectional view which shows the mounting state of the chip resistor of 4th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Chip resistor 12 Insulating substrate 14 Surface electrode 16, 17 Resistor 18 Protruding part 20 Secondary electrode 22 Glass coat 24 Protective layer 26 End surface electrode 28 Plating layer 30 Supporting protrusion 32 Dividing substrate 34 Circuit substrate

Claims (7)

  In a chip resistor in which a pair of surface electrodes is formed on the surface of the insulating substrate and a resistor is provided between the surface electrodes, the chip resistor is formed on the surface electrode so as to protrude from the surface side of the resistor, A chip resistor comprising a support projection for stably supporting an insulating substrate on a circuit board surface.   The chip resistor according to claim 1, wherein the support protrusion is formed of a convex portion formed of an insulating material or a conductive material.   The chip resistor according to claim 1, wherein the support protrusion is formed by laminating a plurality of electrode materials.   The chip resistor according to claim 1, wherein the support protrusion is formed by laminating the resistor on the surface electrode.   A resistor and a surface electrode connected to both ends of the resistor are formed on the surface of the insulating substrate, and an insulator or conductor paste is formed on the pair of surface electrodes so as to protrude from the protective layer of the resistor. Is applied to form a convex portion, and the convex portion is used to form a support protrusion that stably supports the chip resistor on the surface of the circuit board.   A resistor and a surface electrode laminated on both ends of the resistor are formed on the surface of the insulating substrate, a plurality of layers of the resistor and electrode material are laminated, and the chip resistor is projected from the protective layer of the resistor. Chip resistor manufacturing method for forming support protrusions for stable support on a substrate surface 7. The chip resistor according to claim 5, wherein the support protrusion is provided on the insulating substrate formed on the entire surface of the resistor.

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