Chip resistor and method for manufacturing chip resistor

Abstract

Provided is a chip resistor in which a first trimming groove comprises a first linear part extending linearly from a first edge along the X-axis direction, and a second linear part extending linearly along the Y-axis direction. A second trimming groove includes: a third linear part disposed on a second upper surface electrode side of the first linear part and extending linearly from the first edge along a first linear part 1; and a fourth linear part disposed on a second edge side of the second linear part and extending linearly from the leading end of the third linear part along the second linear part. As viewed in the X-axis direction, the leading end of the second trimming groove is positioned closer to the second upper surface electrode side than the leading end of the first trimming groove.

Description

Chip resistor and method for manufacturing chip resistor

[0001] The present disclosure generally relates to a chip resistor and a method for manufacturing the same, and more particularly to a chip resistor including a pair of electrodes and a resistive element, and a method for manufacturing the same.

[0002] Patent Document 1 discloses a chip resistor in which two L-shaped grooves (trimming grooves) are formed side by side in a resistor element formed on an insulating substrate.

[0003] JP 2014-17378 A

[0004] Generally, when a voltage is applied to a resistor, a potential difference occurs in the L-shaped groove according to the shape of the groove. When a high voltage is applied, this potential difference can cause dielectric breakdown in the groove, which can cause fluctuations in the resistance value.

[0005] In the chip resistor described in Patent Document 1, one groove is formed in the ineffective region of the other groove, but the other groove formed in the ineffective region can hardly reduce the potential difference occurring in the one groove.

[0006] On the other hand, when a laser is used to form the trimming groove, there are technical limitations to widening the trimming groove width, making it relatively difficult to increase the voltage resistance of the trimming groove, which can become the voltage limit of the chip resistor.

[0007] A chip resistor according to one aspect of the present disclosure includes a substrate, a first electrode, a second electrode, a resistor, a first trimming groove, and a second trimming groove. The first electrode and the second electrode are provided on both ends of one surface of the substrate in a first direction. The resistor is provided on the one surface of the substrate between the first electrode and the second electrode and has a first edge and a second edge extending along the first direction. The first trimming groove is formed in the resistor and has a first linear portion extending linearly from the first edge to its tip along a second direction perpendicular to the first direction, and a second linear portion extending linearly from the tip of the first linear portion along the first direction. The second trimming groove is formed in the resistor and has a third linear portion disposed on the second electrode side of the first linear portion and extending linearly from the first edge to its tip along the first linear portion, and a fourth linear portion disposed on the second edge side of the second linear portion and extending linearly from the tip of the third linear portion along the second linear portion. When viewed in the second direction, the tip of the second trimming groove located farthest from the second electrode is positioned closer to the second electrode than the tip of the first trimming groove located farthest from the second electrode.

[0008] A method for manufacturing a chip resistor according to one aspect of the present disclosure includes the steps of: forming a first electrode and a second electrode on both ends of a first direction of a surface of a substrate; forming a resistor on the surface of the substrate between the first electrode and the second electrode, the resistor having first and second edges extending along the first direction; forming a first trimming groove in the resistor; and forming a second trimming groove in the resistor. The first trimming groove has a first linear portion extending linearly from the first edge to its tip along a second direction perpendicular to the first direction, and a second linear portion extending linearly from the tip of the first linear portion along the first direction. The second trimming groove has a third linear portion disposed on the second electrode side of the first linear portion and extending linearly from the first edge to its tip along the first linear portion, and a fourth linear portion disposed on the second edge side of the second linear portion and extending linearly from the tip of the third linear portion along the second linear portion. When viewed in the second direction, the tip of the second trimming groove located farthest from the second electrode is positioned closer to the second electrode than the tip of the first trimming groove located farthest from the second electrode.

[0009] According to the present disclosure, a chip resistor with high withstand voltage and a method for manufacturing the chip resistor can be obtained.

[0010] FIG. 1 is a schematic plan view of a chip resistor according to a first embodiment of the present disclosure. FIG. 2 is a graph showing changes in the potential difference across each groove of the same chip resistor relative to L2 / L1 (L1 is the distance between the tip of the first trimming groove and the second upper surface electrode, and L2 is the distance between the tip of the second trimming groove and the second upper surface electrode). FIG. 3 is a graph showing changes in the potential difference across each groove of the same chip resistor relative to L2 / L1 (L1 is the distance between the tip of the second trimming groove and the second upper surface electrode) in the same chip resistor according to a modified example of the first embodiment. FIG. 4 is a schematic plan view of a chip resistor according to a second embodiment of the present disclosure. FIG. 5 is a graph showing changes in the potential difference across each groove of the same chip resistor relative to L2 / L1 (L3 is the distance between the tip of the third trimming groove and the second upper surface electrode). FIG. 7 is a schematic plan view of a chip resistor according to a third embodiment of the present disclosure.

[0011] Hereinafter, chip resistors and methods for manufacturing chip resistors according to embodiments will be described with reference to the drawings. The figures described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Furthermore, the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0012] In the drawings, the X-axis, Y-axis, and Z-axis are perpendicular to one another, but this is merely an example and is not intended to define the directions in which the chip resistor should be used.

[0013] First Embodiment (1) Basic Configuration of Chip Resistor Hereinafter, a first embodiment will be described with reference to FIG.

[0014] The chip resistor 1 is a chip resistor for surface mounting (SMT: Surface Mount Technology) that is mounted on the surface (mounting surface) of a printed circuit board using, for example, a surface mounter. In this embodiment, as an example, the chip resistor 1 is a thick-film chip resistor.

[0015] 1, the chip resistor 1 mainly includes an insulating substrate 2 (substrate), a first upper surface electrode 3 (first electrode), a second upper surface electrode 4 (second electrode), and a resistor 5. The chip resistor 1 also includes a first lower surface electrode, a second lower surface electrode, a first end surface electrode, a second end surface electrode, a pair of first plating layers, and a pair of second plating layers. The chip resistor 1 also includes a glass protective film and a resin protective film.

[0016] (2) Insulating Substrate The insulating substrate 2 is made of, for example, Al ２ O ３The insulating substrate 2 is made of alumina containing 96% alumina and has a rectangular shape (rectangular when viewed from above). The longitudinal direction of the insulating substrate 2 is along the Y-axis direction (first direction), the lateral direction is along the X-axis direction (second direction), and the thickness direction is along the Z-axis direction. Furthermore, the left side of Fig. 1 is the longitudinal first side (Y-axis first side), the right side of Fig. 1 is the longitudinal second side (Y-axis second side), the lower side of Fig. 1 is the lateral first side (X-axis first side), and the upper side of Fig. 1 is the lateral second side (X-axis second side).

[0017] The X-axis direction, Y-axis direction, and Y-axis direction are perpendicular to one another, but the concept of "perpendicular" here includes "approximately perpendicular," and includes the range of 90°±10°.

[0018] (3) Upper Surface Electrode The first upper surface electrode 3 and the second upper surface electrode 4 are provided at both longitudinal ends of the surface 21 (one side) of the insulating substrate 2, and are formed by printing and firing a thick film material containing a metal such as silver.

[0019] (4) Resistor (4-1) Overview of Resistor The resistor 5 is formed on the surface 21 of the insulating substrate 2 between the first upper surface electrode 3 and the second upper surface electrode 4, and is connected to the first upper surface electrode 3 and the second upper surface electrode 4. The resistor 5 has a first edge 51 and a second edge 52 extending along the Y-axis direction. The first edge 51 is provided on a first side in the X-axis direction, and the second edge 52 is provided on a second side in the X-axis direction.

[0020] The resistor 5 is formed by printing a thick film material made of, for example, about 10 wt % lead ruthenate, about 53 wt % glass, and about 37 wt % solvent on the surface 21 of the insulating substrate 2 and then baking it.

[0021] (4-2) First Trimming Groove and Second Trimming Groove The resistor 5 is formed with a first trimming groove 11 and a second trimming groove 12 .

[0022] The first trimming groove 11 is L-shaped and includes a first linear portion 111 that extends linearly from the first edge 51 of the resistor 5 to a tip 211 along the X-axis direction, and a second linear portion 112 that extends linearly from the tip 211 of the first linear portion 111 along the Y-axis direction. In other words, the first linear portion 111 has a starting point at the first edge 51 and extends linearly from the first edge 51 to the second edge 52 in the X-axis direction to the tip 211. The second linear portion 112 is an extension that extends linearly from the tip 211 of the first linear portion 111 to a first side in the Y-axis direction. The second linear portion 112 has a tip 113 (the portion of the first trimming groove 11 that is located farthest from the second upper-surface electrode 4 in the Y-axis direction, i.e., as viewed in the X-axis direction). The distance between the second linear portion 112 and the first edge 51 in the X-axis direction, i.e., as viewed in the Y-axis direction, is defined as C1.

[0023] The second trimming groove 12 is formed in the resistor element 5 so as to extend along the first trimming groove 11. The second trimming groove 12 is located on the outer side (convex side) of the L-shaped first trimming groove 11. The second trimming groove 12 is L-shaped and includes a third linear portion 121 that extends linearly from the first edge 51 of the resistor element 5 to a tip 221 along the X-axis direction, and a fourth linear portion 122 that extends linearly from the tip 221 of the third linear portion 121 along the Y-axis direction. In other words, the third linear portion 121 has its starting end at the first edge 51 and extends linearly from the first edge 51 toward the second edge 52 to the tip 221. The fourth linear portion 122 extends from the tip 221 of the third linear portion 121 to the first side in the Y-axis direction. The third linear portion 121 extends linearly along the first linear portion 111 and is located parallel to the first linear portion 111. The fourth linear portion 122 extends linearly along the second linear portion 112 and is disposed parallel to the second linear portion 112. The fourth linear portion 122 has a tip 123 (the portion of the second trimming groove 12 that is located farthest from the second upper surface electrode 4 in the Y-axis direction, i.e., when viewed in the X-axis direction).

[0024] 1 , when viewed in the Y-axis direction, i.e., the X-axis direction, the tip 123 of the fourth linear portion 122 of the second trimming groove 12 is located closer to the second top surface electrode 4 than the tip 113 of the second linear portion 112 of the first trimming groove 11. Therefore, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. As a result, even when the chip resistor 1 is used at high voltage, insulation breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0025] More specifically, when viewed in the Y-axis direction (i.e., the X-axis direction), the distance between the edge 41 of the second upper surface electrode 4 on the first upper surface electrode 3 side and the tip 113 of the second linear portion 112 of the first trimming groove 11 is defined as L1, and the distance between the edge 41 of the second upper surface electrode 4 and the tip 123 of the fourth linear portion 122 of the second trimming groove 12 is defined as L2. Specifically, L2 / L1 is greater than or equal to 0.3 and less than or equal to 0.7 (as a percentage, L2 / L1 is in the range of 30 to 70%). Therefore, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. As a result, even when the chip resistor 1 is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, resulting in less characteristic abnormalities.

[0026] (5) Effects The effects of the chip resistor 1 will be described with reference to FIG.

[0027] (5-1) Overview of the Simulation Figure 2 shows the simulation results of the potential difference between the two sides of the groove starting point of the first trimming groove 11 and the second trimming groove 12 when L2 / L1 in the chip resistor 1 is changed in the range of 10 to 98%.

[0028] (5-2) Simulation Conditions The length of insulating substrate 2 in the Y-axis direction is 3.1 mm, the length of insulating substrate 2 in the X-axis direction is 1.5 mm, the length of resistor 5 in the Y-axis direction is 1.9 mm, and the length of resistor 5 in the X-axis direction is 1.1 mm. Furthermore, the distance between second linear portion 112 of first trimming groove 11 and fourth linear portion 122 of second trimming groove 12 is 0.06 mm. Furthermore, the distance between first linear portion 111 of first trimming groove 11 and second upper surface electrode 4 is 0.26 mm, and the distance between third linear portion 121 of second trimming groove 12 and second upper surface electrode 4 is 0.20 mm.

[0029] It should be noted that L1 is 1.76 mm and C1 is 0.4 mm.

[0030] (5-3) Simulation Results Figure 2 shows the potential difference when a voltage of 500 V is applied to the first upper surface electrode 3 and the second upper surface electrode 4 of the chip resistor 1. In Figure 2, V1 represents the potential difference in the first trimming groove 11, V2 represents the potential difference in the second trimming groove 12, and V0 represents the potential difference in the first trimming groove 11 when the second trimming groove 12 is not present.

[0031] As is clear from Figure 2, if L2 / L1 < 95%, then V1 < V0 and V2 < V0. In other words, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. Therefore, even when chip resistor 1 is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0032] When L2 / L1=100%, V2 is approximately equal to V0, and this shows that if the tip positions of the two trimming grooves are the same, the potential difference cannot be reduced.

[0033] 2, it can be seen that L2 / L1 is preferably in the range of 30 to 70%. In particular, when L2 / L1 is about 50% (e.g., 46.8%), V1 and V2 have the same value (e.g., 244 V), which is about half (e.g., 51%) of V0 (486 V). In other words, in this case, the maximum potential difference between the two trimming grooves is minimized.

[0034] (6) Method for Manufacturing Chip Resistor A method for manufacturing the chip resistor 1 will now be described. However, for the sake of simplicity, only the formation of the first upper surface electrode 3, the second upper surface electrode 4, and the resistor 5 will be described.

[0035] First, an electrode paste is screen-printed on both longitudinal ends of an insulating substrate 2 made of alumina, and then fired at 850° C. to form a first upper surface electrode 3 and a second upper surface electrode 4 .

[0036] Next, a resistive paste is screen-printed between the first upper surface electrode 3 and the second upper surface electrode 4, and then fired at 850° C. to form the resistor 5.

[0037] Next, the first trimming groove 11 is formed by laser processing.

[0038] Next, laser processing is used to form second trimming grooves 12. In this way, the resistance value can be roughly adjusted by forming first trimming grooves 11 first, and then the resistance value can be finely adjusted when forming second trimming grooves 12, thereby increasing the accuracy of the resistance value. This is because the resistance value of second trimming grooves 12 changes little with length.

[0039] The order of forming the first upper surface electrode 3, the second upper surface electrode 4 and the resistor 5 may be reversed.

[0040] Furthermore, the order in which first trimming groove 11 and second trimming groove 12 are formed may be reversed.

[0041] (Modification of First Embodiment) The effect of the chip resistor 1 of the modification will be described with reference to Fig. 3. Note that the basic configuration and basic operation of this modification are the same as those of the first embodiment, so the description will focus on the differences.

[0042] The difference from the first embodiment is that the length of L1 has been changed (shortened).

[0043] (1) Overview of the Simulation Figure 3 shows the simulation results of the potential difference between the two sides of the groove starting point of the first trimming groove 11 and the second trimming groove 12 when L2 / L1 in the chip resistor 1 is changed in the range of 10 to 98%.

[0044] (2) Simulation Conditions L1 is 0.76 mm, which is shorter than that in the first embodiment, and C1 is 0.4 mm.

[0045] (3) Simulation Results Fig. 3 shows the potential difference when a voltage of 500 V is applied to the first upper surface electrode 3 and the second upper surface electrode 4 of the chip resistor 1. In Fig. 3, V1 represents the potential difference in the first trimming groove 11, V2 represents the potential difference in the second trimming groove 12, and V0 represents the potential difference in the first trimming groove 11 when the second trimming groove 12 is not present.

[0046] As is clear from Figure 3, if L2 / L1 < 95%, then V1 < V0 and V2 < V0. In other words, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. Therefore, even when chip resistor 1 is used at high voltage, insulation breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur. Note that the larger L1 and C1 are, the greater the potential difference.

[0047] 3, it can be seen that L2 / L1 is preferably in the range of 30 to 70%. In particular, when L2 / L1 is about 50% (e.g., 51.0%), V1 and V2 have the same value (e.g., 147 V), which is about half (e.g., 51%) of V0 (293 V). In other words, in this case, the maximum potential difference between the two trimming grooves is minimized.

[0048] Second Embodiment In the first embodiment described above, two trimming grooves are provided, but three trimming grooves may be provided.

[0049] 4 and 5, a chip resistor 1A having three trimming grooves will be described as a second embodiment. Note that the basic configuration of the chip resistor 1A is the same as that of the chip resistor 1 according to the first embodiment, so the differences will be mainly described.

[0050] (1) Basic Structure of Chip Resistor As shown in FIG. 4, a chip resistor 1A mainly includes an insulating substrate 2A, a first upper surface electrode 3A, a second upper surface electrode 4A, and a resistive element 5A.

[0051] (2) Insulating Substrate The insulating substrate 2A is made of, for example, Al ２ O ３The insulating substrate 2A is made of alumina containing 96% of arsenic and has a rectangular shape (rectangular when viewed from above). The longitudinal direction of the insulating substrate 2A is along the Y axis, the lateral direction is along the X axis, and the thickness direction is along the Z axis.

[0052] (3) Upper Surface Electrode The first upper surface electrode 3A and the second upper surface electrode 4A are provided at both longitudinal ends of the surface 21A of the insulating substrate 2A, and are formed by printing and firing a thick film material containing a metal such as silver.

[0053] (4) Resistor (4-1) Overview of Resistor The resistor 5A is formed on the surface 21A (one surface) of the insulating substrate 2A between the first upper surface electrode 3A and the second upper surface electrode 4A, and is connected to the first upper surface electrode 3A and the second upper surface electrode 4A. The resistor 5A has a first edge 51A and a second edge 52A extending along the Y-axis direction. The first edge 51A is provided on a first side in the X-axis direction, and the second edge 52A is provided on a second side in the X-axis direction.

[0054] (4-2) First Trimming Groove, Second Trimming Groove, and Third Trimming Groove The resistor 5A is formed with a first trimming groove 11A, a second trimming groove 12A, and a third trimming groove 13A.

[0055] The first trimming groove 11A is L-shaped and includes a first linear portion 111A extending linearly from the first edge 51A of the resistor 5A along the X-axis direction to a tip 211, and a second linear portion 112A extending linearly from the tip 211 of the first linear portion 111A along the Y-axis direction. In other words, the first linear portion 111A has a starting point at the first edge 51A and extends linearly from the first edge 51A toward the second edge 52A in the X-axis direction to the tip 211. The second linear portion 112A extends linearly from the tip 211 of the first linear portion 111A toward the first side in the Y-axis direction. The second linear portion 112A has a tip 113A (the portion of the first trimming groove 11A farthest from the second upper-surface electrode 4A in the Y-axis direction, i.e., as viewed in the X-axis direction). The distance between the second linear portion 112A and the first edge 51A is defined as C1.

[0056] The second trimming groove 12A is formed in the resistor element 5A so as to extend along the first trimming groove 11A. The second trimming groove 12A is located on the outer side (convex side) of the L-shaped first trimming groove 11A. The second trimming groove 12A is L-shaped and includes a third linear portion 121A that extends linearly from the first edge 51A of the resistor element 5A along the X-axis direction to a tip 221, and a fourth linear portion 122A that extends linearly from the tip 221 of the third linear portion 121A along the Y-axis direction. In other words, the third linear portion 121A has its starting end at the first edge 51A and extends linearly from the first edge 51A toward the second edge 52A to the tip 221. The fourth linear portion 122A extends linearly from the tip 221 of the third linear portion 121A toward the first side in the Y-axis direction. The third linear portion 121A extends linearly along the first linear portion 111A and is disposed parallel to the first linear portion 111A. The fourth linear portion 122A extends linearly along the second linear portion 112A and is disposed parallel to the second linear portion 112A. The fourth linear portion 122A has a tip 123A (the portion of the second trimming groove 12A that is located farthest from the second upper surface electrode 4A in the Y-axis direction, i.e., when viewed in the X-axis direction).

[0057] The third trimming groove 13A is formed in the resistor 5A so as to extend along the second trimming groove 12A. The third trimming groove 13A is located on the outer side (convex side) of the L-shaped second trimming groove 12A. The third trimming groove 13A is L-shaped and includes a fifth linear portion 131A extending linearly from the first edge 51A of the resistor 5A along the X-axis direction to a tip 231, and a sixth linear portion 132A extending linearly from the tip 231 of the fifth linear portion 131A along the Y-axis direction. In other words, the fifth linear portion 131A has its starting end at the first edge 51A and extends linearly from the first edge 51A toward the second edge 52A to the tip 231. The sixth linear portion 132A extends linearly from the tip 231 of the fifth linear portion 131A toward the first side in the Y-axis direction. Fifth linear portion 131A extends linearly along third linear portion 121A and is disposed parallel to third linear portion 121A. Sixth linear portion 132A extends linearly along fourth linear portion 122A and is disposed parallel to fourth linear portion 122A. Sixth linear portion 132A has tip 133A (the portion of third trimming groove 13A that is located farthest from second top surface electrode 4A in the Y-axis direction, i.e., when viewed in the X-axis direction).

[0058] In FIG. 4 , when viewed in the Y-axis direction (i.e., the X-axis direction), the tip 123A of the fourth linear portion 122A of the second trimming groove 12A is located closer to the second top surface electrode 4A than the tip 113A of the second linear portion 112A of the first trimming groove 11A. Furthermore, when viewed in the Y-axis direction (i.e., the X-axis direction), the tip 133A of the sixth linear portion 132A of the third trimming groove 13A is located closer to the second top surface electrode 4A than the tip 123A of the fourth linear portion 122A of the second trimming groove 12A. Therefore, the potential difference between the trimming grooves is smaller than in the case of a single trimming groove. As a result, even when the chip resistor 1A is used at high voltages, dielectric breakdown in the trimming grooves is less likely to occur, resulting in less characteristic abnormalities.

[0059] More specifically, when viewed in the Y-axis direction (i.e., the X-axis direction), the distance between the edge 41A of the second upper-surface electrode 4A on the first upper-surface electrode 3A side and the tip 113A of the second straight portion 112A of the first trimming groove 11A is defined as L1, the distance between the edge 41A of the second upper-surface electrode 4A and the tip 123A of the fourth straight portion 122A of the second trimming groove 12A is defined as L2, and the distance between the edge 41A of the second upper-surface electrode 4A and the tip 133A of the sixth straight portion 132A is defined as L3, and L1 > L2 > L3 is satisfied. Specifically, L2 / L1 is 0.4 to 0.8, and L3 / L1 is 0.1 to 0.5 (in percentages, L2 / L1 is in the range of 40 to 80%, and L3 / L1 is in the range of 10 to 50%). Therefore, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. As a result, even when chip resistor 1A is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0060] (5) Effects The effects of the chip resistor 1A will be described with reference to FIG.

[0061] (5-1) Overview of the Simulation Figure 5 shows the simulation results of the potential difference between both sides of the groove starting points of the first trimming groove 11, the second trimming groove 12, and the third trimming groove 13A when the ratio L2 / L1 of the distance L2 between the tip 123A of the fourth straight portion 122A of the second trimming groove 12A and the second upper surface electrode 4A to the distance L1 between the tip 113A of the second straight portion 112A of the first trimming groove 11A and the second upper surface electrode 4 in the chip resistor 1A is changed in the range of 13 to 100%.

[0062] (5-2) Simulation Conditions The length of insulating substrate 2A in the Y-axis direction was 3.1 mm, the length of insulating substrate 2A in the X-axis direction was 1.5 mm, the length of resistor 5A in the Y-axis direction was 1.9 mm, and the length of resistor 5A in the X-axis direction was 1.1 mm. Furthermore, the distance in the X-axis direction between second linear portion 112A of first trimming groove 11A and fourth linear portion 122A of second trimming groove 12A was 0.06 mm. The distance in the X-axis direction between first linear portion 111A of first trimming groove 11A and second upper-surface electrode 4A was 0.32 mm, the distance between third linear portion 121A of second trimming groove 12A and second upper-surface electrode 4A was 0.26 mm, and the distance between fifth linear portion 131A of third trimming groove 13A and second upper-surface electrode 4A was 0.20 mm.

[0063] It should be noted that L1 is 1.76 mm and C1 is 0.4 mm.

[0064] Furthermore, L3 / L1 is fixed at 29%.

[0065] (5-3) Simulation Results Fig. 5 shows the potential difference when a voltage of 500 V is applied to the first upper surface electrode 3A and the second upper surface electrode 4A of the chip resistor 1A. In Fig. 5, V1 represents the potential difference in the first trimming groove 11A, V2 represents the potential difference in the second trimming groove 12A, V3 represents the potential difference in the third trimming groove 13A, and V0 represents the potential difference in the first trimming groove 11A in the absence of the second trimming groove 12A and the third trimming groove 13A.

[0066] As is clear from Figure 5, if L2 / L1 < 100%, then V1 < V0, V2 < V0, and V3 < V0. In other words, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. Therefore, even when chip resistor 1A is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0067] 5, it can be seen that it is preferable for L2 / L1 to be in the range of 40 to 80%. In particular, when L2 / L1 is about 60% (e.g., 63%), V1, V2, and V3 have the same value (e.g., 164 V). In other words, in this case, the maximum value of the potential difference between the three trimming grooves is minimized.

[0068] (Modification of Second Embodiment) The effect of a chip resistor 1A according to a modification of the second embodiment will be described with reference to Fig. 6. Note that the basic configuration and basic operation of this modification are the same as those of the second embodiment, and therefore differences will be mainly described.

[0069] The difference from the second embodiment is that L2 / L1 is fixed, rather than L3 / L1 being fixed.

[0070] (1) Overview of the Simulation Figure 6 shows the simulation results of the potential difference on both sides of the groove starting points of the first trimming groove 11A, the second trimming groove 12A, and the third trimming groove 13A when the ratio L2 / L1 of the distance L2 between the tip 133A of the sixth straight portion 132A of the third trimming groove 13A and the second upper surface electrode 4A to the distance L1 between the tip 113A of the second straight portion 112A of the first trimming groove 11A and the second upper surface electrode 4 in the chip resistor 1A is changed in the range of 15 to 100%.

[0071] (2) Simulation Conditions L2 / L1 is fixed at 63%.

[0072] (3) Simulation Results Fig. 6 shows the potential difference when a voltage of 500 V is applied to the first upper surface electrode 3A and the second upper surface electrode 4A of the chip resistor 1A. In Fig. 6, V1 represents the potential difference across the first trimming groove 11A, V2 represents the potential difference across the second trimming groove 12A, V3 represents the potential difference across the third trimming groove 13A, and V0 represents the potential difference across the first trimming groove 11A in the absence of the second trimming groove 12A and the third trimming groove 13A.

[0073] As is clear from Figure 6, if L3 / L1 < 95%, then V1 < V0, V2 < V0, and V3 < V0. In other words, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. Therefore, even when chip resistor 1A is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0074] 6, it can be seen that L3 / L1 is preferably in the range of 10 to 50%. In particular, when L3 / L1 is about 30% (e.g., 29%), V1, V2, and V3 have the same value (e.g., 164 V). In other words, in this case, the maximum value of the potential difference between the three trimming grooves is minimized.

[0075] Third Embodiment In the first and second embodiments, the first trimming groove and the second trimming groove are L-shaped, but they may have other shapes.

[0076] 7, a chip resistor 1B in which a tip portion is further formed at the tip of the first trimming groove will be described. Note that the basic configuration of the chip resistor 1B is the same as that of the chip resistor 1 according to the first embodiment, and therefore differences will be mainly described.

[0077] (1) Basic Structure of Chip Resistor As shown in FIG. 7, a chip resistor 1B mainly includes an insulating substrate 2B, a first upper surface electrode 3B, a second upper surface electrode 4B, and a resistive element 5B.

[0078] (2) Insulating Substrate The insulating substrate 2B is made of, for example, Al ２ O ３ 7 is made of alumina containing 96% alumina and has a rectangular shape (rectangular in top view). The insulating substrate 2B has a longitudinal direction along the Y-axis direction (first direction), a lateral direction along the X-axis direction (second direction), and a thickness direction along the Z-axis direction. Furthermore, the left side of Fig. 7 is the longitudinal first side (Y-axis first side), the right side of Fig. 7 is the longitudinal second side (Y-axis second side), the lower side of Fig. 7 is the lateral first side (X-axis first side), and the upper side of Fig. 7 is the lateral second side (X-axis second side).

[0079] (3) Upper Surface Electrode The first upper surface electrode 3B and the second upper surface electrode 4B are provided at both longitudinal ends of the surface 21B of the insulating substrate 2B, and are formed by printing and firing a thick film material containing a metal such as silver.

[0080] (4) Resistor (4-1) Overview of Resistor The resistor 5B is formed on the surface 21B of the insulating substrate 2B between the first upper surface electrode 3B and the second upper surface electrode 4B, and is connected to the first upper surface electrode 3B and the second upper surface electrode 4B. The resistor 5B has a first edge 51B and a second edge 52B extending along the Y-axis direction. The first edge 51B is provided on a first side in the X-axis direction, and the second edge 52B is provided on a second side in the X-axis direction.

[0081] (4-2) First Trimming Groove and Second Trimming Groove The resistor 5B is formed with a first trimming groove 11B and a second trimming groove 12B.

[0082] The first trimming groove 11B has a first linear portion 111B that extends linearly from the first edge 51B of the resistor 5B along the X-axis direction to a tip 211, and a second linear portion 112B that extends from the tip 211 of the first linear portion 111B along the Y-axis direction. In other words, the first linear portion 111B has a starting point at the first edge 51B and extends from the first edge 51B toward the second edge 52B in the X-axis direction to the tip 211. The second linear portion 112B extends linearly from the tip 211 of the first linear portion 111B to the first side in the Y-axis direction to the tip 212. The distance between the second linear portion 112B and the first edge 51B is defined as C1.

[0083] First trimming groove 11B has tip portion 113B extending from tip 212 of second straight portion 112B in a direction different from that of second straight portion 112B. Tip portion 113B forms an extension together with second straight portion 112B, and extends from tip 212 of second straight portion 112B while bending back in a direction approaching second top-surface electrode 4B. Tip portion 113B is located on the opposite side of second straight portion 112B of first trimming groove 11B from first edge 51. More specifically, tip portion 113B has semicircular curved portion 313B extending in a semicircular arc from tip 212 of second straight portion 112B to tip 212B, and linear portion 413B extending linearly from tip 212B of semicircular curved portion 313B to terminal end 114B. The tip of the straight portion 413B of the tip portion 113B is the terminal end 114B, and the tip of the semicircular curved portion 313B of the tip portion 113B (the part located farthest from the second upper surface electrode 4B of the first trimming groove 11B in the Y-axis direction, i.e., when viewed in the X-axis direction) is the curved portion tip 115B.

[0084] In the above configuration, first trimming groove 11B has tip 113B, which reduces load concentration at the tip end of first trimming groove 11B in the extension direction. As a result, power durability is improved. Furthermore, microcracks are less likely to occur at the tip end of first trimming groove 11B in the extension direction. In particular, tip 113B has at least a partial arc portion, which makes it less likely for resistance value accuracy to decrease.

[0085] The second trimming groove 12B is formed in the resistor element 5B so as to extend along the first trimming groove 11B. The second trimming groove 12B is located on the outer side (convex side) of the L-shaped first trimming groove 11B. The second trimming groove 12B is L-shaped and includes a third linear portion 121B extending from the first edge 51B of the resistor element 5B along the X-axis direction to a tip 221, and a fourth linear portion 122B extending from the tip 221 of the third linear portion 121B along the Y-axis direction. In other words, the third linear portion 121B has its starting end at the first edge 51B and extends from the first edge 51B toward the second edge 52B to the tip 221. The fourth linear portion 122B extends from the tip 221 of the third linear portion 121B toward the first side in the Y-axis direction. The third linear portion 121B extends linearly along the first linear portion 111B and is disposed parallel to the first linear portion 111B. The fourth linear portion 122B corresponds to the second linear portion 112B and is disposed parallel to the second linear portion 112B. The fourth linear portion 122B has a tip 123B (the portion of the second trimming groove 12B that is located farthest from the second upper surface electrode 4B in the Y-axis direction, i.e., when viewed in the X-axis direction).

[0086] 7, when viewed in the Y-axis direction, i.e., the X-axis direction, the tip 123B of the fourth linear portion 122B of the second trimming groove 12B is located closer to the second top surface electrode 4B than the tip 115B (tip of the extension) of the curved portion of the first trimming groove 11B. Therefore, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. As a result, even when the chip resistor 1B is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0087] End 114B of tip 113B of first trimming groove 11B is positioned at a gap G1 in the Y-axis direction from tip 123B of fourth linear portion 122B. Because the microcracks at end 114B of first trimming groove 11B are oriented in the same direction as the current path, the resistance value remains almost unchanged even if the microcracks grow, improving the accuracy and reliability of the resistance value.

[0088] When viewed in the Y-axis direction (i.e., the X-axis direction), the distance between the edge 41B of the second upper surface electrode 4B on the first upper surface electrode 3B side and the tip 115B of the curved portion of the first trimming groove 11B is defined as L1, and the distance between the edge 41B of the second upper surface electrode 4B and the tip 123B of the fourth linear portion 122B of the second trimming groove 12B is defined as L2. Specifically, L2 / L1 is greater than or equal to 0.3 and less than or equal to 0.7 (as a percentage, L2 / L1 is in the range of 30 to 70%). Therefore, the potential difference in each trimming groove is smaller than in the case of a single trimming groove. As a result, even when the chip resistor 1B is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, resulting in less characteristic abnormalities.

[0089] (Variation of the Third Embodiment) The direction in which the tip 113B of the first trimming groove extends is not limited as long as it extends in a direction different from the direction in which the second linear portion 112B extends. Furthermore, the shape and length of the tip of the trimming groove are not particularly limited. However, it is preferable that the tip be smooth and free of corners.

[0090] The tip portion may have a straight portion extending at an angle from the tip of the second straight portion. The tip portion may be bent in two steps in a perpendicular direction so as to fold back relative to the second straight portion.

[0091] (Modifications of the First to Third Embodiments) The above-described embodiments are merely one of various embodiments of the present disclosure. The above-described embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Modifications of the above-described embodiments are listed below. The modifications described below can be applied in appropriate combinations.

[0092] The chip resistors 1, 1A, and 1B may be thin film chip resistors.

[0093] The trimming grooves may include curves or other shapes other than straight lines.

[0094] (Aspects) The present specification discloses the following aspects.

[0095] A chip resistor (1, 1A, 1B) according to a first aspect includes a substrate (2, 2A, 2B), a first electrode (3, 3A, 3B), a second electrode (4, 4A, 4B), a resistor (5, 5A, 5B), a first trimming groove (11, 11A, 11B), and a second trimming groove (12, 12A, 12B). The first electrode (3, 3A, 3B) and the second electrode (4, 4A, 4B) are provided at both ends in a first direction (Y) on one surface (21, 21A, 21B) of the substrate (2, 2A, 2B). The resistor (5, 5A, 5B) is arranged between a first electrode (3, 3A, 3B) and a second electrode (4, 4A, 4B) on one surface (21, 21A, 21B) of the substrate (2, 2A, 2B), and has a first edge (51, 51A, 51B) and a second edge (52, 52A, 52B) extending along a first direction (Y). The first trimming groove (11, 11A, 11B) has a first linear portion (111, 111A, 111B) extending linearly from the first edge (51, 51A, 51B) to a tip (211) along a second direction (X) perpendicular to the first direction (Y), and a second linear portion (112, 112A, 112B) extending linearly from the tip (211) of the first linear portion (111, 111A, 111B) along the first direction (Y). The second trimming groove (12, 12A, 12B) has a third linear portion (121, 121A, 121B) that is arranged on the second electrode (4, 4A, 4B) side of the first linear portion (111, 111A, 111B) and extends linearly from the first edge (51, 51A, 51B) along the first linear portion (111, 111A, 111B) to the tip (221), and a fourth linear portion (122, 122A, 122B) that is arranged on the second edge (52, 52A, 52B) side of the second linear portion (112, 112A, 112B) and extends linearly from the tip (221) of the third linear portion (121, 121A, 121B) along the second linear portion (112, 112A, 112B). When viewed in the second direction (X), the tips (123, 123A, 123B) of the second trimming grooves (12, 12A, 12B) located farthest from the second electrodes (4, 4A, 4B) are located closer to the second electrodes (4, 4A, 4B) than the tips (113, 113A, 115B) of the first trimming grooves (11, 11A, 11B) located farthest from the second electrodes (4, 4A, 4B).

[0096] According to this embodiment, the potential difference in each trimming groove is smaller than in the case of a single trimming groove, and as a result, even when the chip resistor (1, 1A, 1B) is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0097] In the chip resistor (1, 1B) according to the second aspect, in the first aspect, when viewed in the second direction (X), the distance between the edge (41, 41B) of the second electrode (4, 4B) on the first electrode (3, 3B) side and the tip (113, 115B) of the first trimming groove (11, 11B) is L1, and the distance between the edge (41, 41B) of the second electrode (4, 4B) and the tip (123, 123B) of the second trimming groove (12, 12B) is L2, L2 / L1 is 0.3 or more and 0.7 or less.

[0098] According to this embodiment, the potential difference in each trimming groove is smaller than in the case of a single trimming groove, and as a result, even when the chip resistor (1, 1B) is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0099] The chip resistor (1A) according to the third aspect is the same as that according to the first aspect, but further includes a third trimming groove (13A). The third trimming groove (13A) has a fifth linear portion (131A) disposed on the second electrode (4A) side of the third linear portion (121A) and extending linearly from the first edge (51A) along the third linear portion (121A) to a tip (231), and a sixth linear portion (132A) disposed on the second edge (52A) side of the fourth linear portion (122A) and extending linearly from the tip (231) of the fifth linear portion (131A) along the fourth linear portion (122A). When viewed in the second direction (X), the tip (133A) of the third trimming groove (13A), which is located farthest from the second electrode (4A), is located closer to the second electrode (4A) than the tip (123A) of the second trimming groove (12A).

[0100] According to this embodiment, the potential difference in each trimming groove is smaller than in the case of a single trimming groove, and as a result, even when the chip resistor (1A) is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0101] In the chip resistor (1A) according to the fourth aspect, in the third aspect, when viewed in the second direction (X), the distance between the edge (41A) of the second electrode (4A) on the first electrode (3A) side and the tip (113A) of the first trimming groove (11A) is L1, the distance between the edge (41A) of the second electrode (4A) and the tip (123A) of the second trimming groove (12A) is L2, and the distance between the edge (41A) of the second electrode (4A) and the tip (133A) of the third trimming groove (13A) is L3, L2 / L1 is 0.4 or more and 0.8 or less, and L3 / L1 is 0.1 or more and 0.5 or less.

[0102] According to this embodiment, the potential difference in each trimming groove is smaller than in the case of a single trimming groove, and as a result, even when the chip resistor (1A) is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0103] In the chip resistor (1B) according to the fifth aspect, in any of the first to fourth aspects, the first trimming groove (11B) further has a tip portion (113B) extending from the tip of the second straight portion (112B) in a direction different from that of the second straight portion (112B).

[0104] According to this aspect, it is possible to reduce load concentration in the first direction of the first trimming groove (11B), i.e., in the tip end portion as viewed in the second direction, thereby improving the power durability.

[0105] In the chip resistor (1B) according to the sixth aspect, in the fifth aspect, the end (114B) of the tip portion (113B) of the first trimming groove (11B) is positioned at a position with a gap (G1) in the first direction (Y) from the tip (123B) of the fourth straight portion (122B).

[0106] According to this aspect, the microcracks at the ends (114B) of the first trimming grooves (11B) are oriented in the same direction as the current path, so that the resistance value hardly changes even if the microcracks grow, i.e., the accuracy and reliability of the resistance value are improved.

[0107] A method for manufacturing a chip resistor (1, 1A, 1B) according to a seventh aspect includes a step of forming first electrodes (3, 3A, 3B) and second electrodes (4, 4A, 4B) at both ends in a first direction (Y) of one surface (21, 21A, 21B) of a substrate (2, 2A, 2B), and a step of forming a wiring between the first electrodes (3, 3A, 3B) and the second electrodes (4, 4A, 4B) on the one surface (21, 21A, 21B) of the substrate (2, 2A, 2B). The method includes a step of forming resistors (5, 5A, 5B) having first edges (51, 51A, 51B) and second edges (52, 52A, 52B) extending along a first direction (Y) between the resistors (5, 5A, 5B), a step of forming first trimming grooves (11, 11A, 11B) in the resistors (5, 5A, 5B), and a step of forming second trimming grooves (12, 12A, 12B) in the resistors (5, 5A, 5B). The first trimming groove (11, 11A, 11B) has a first linear portion (111, 111A, 111B) extending linearly from the first edge (51, 51A, 51B) to a tip (211) along a second direction (X) perpendicular to the first direction (Y), and a second linear portion (112, 112A, 112B) extending linearly from the tip (211) of the first linear portion (111, 111A, 111B) along the first direction (Y). The second trimming groove (12, 12A, 12B) has a third linear portion (121, 121A, 121B) that is arranged on the second electrode (4, 4A, 4B) side of the first linear portion (111, 111A, 111B) and extends linearly from the first edge (51, 51A, 51B) along the first linear portion (111, 111A, 111B) to the tip (221), and a fourth linear portion (122, 122A, 122B) that is arranged on the second edge (52, 52A, 52B) side of the second linear portion (112, 112A, 112B) and extends linearly from the tip (221) of the third linear portion (121, 121A, 121B) along the second linear portion (112, 112A, 112B). When viewed in the second direction (X), the tips (123, 123A, 123B) of the second trimming grooves (12, 12A, 12B) located farthest from the second electrodes (4, 4A, 4B) are located closer to the second electrodes (4, 4A, 4B) than the tips (113, 113A, 115B) of the first trimming grooves (11, 11A, 11B) located farthest from the second electrodes (4, 4A, 4B).

[0108] According to this embodiment, the potential difference in each trimming groove is smaller than in the case of a single trimming groove, and as a result, even when the chip resistor (1, 1A, 1B) is used at high voltage, dielectric breakdown in the trimming groove is less likely to occur, and as a result, characteristic abnormalities are less likely to occur.

[0109] In the method for manufacturing a chip resistor according to the eighth aspect, in the seventh aspect, the step of forming the second trimming groove (12, 12A, 12B) is carried out after the step of forming the first trimming groove (11, 11A, 11B).

[0110] According to this aspect, the resistance value is roughly adjusted by first forming the first trimming grooves (11, 11A, 11B), and then the resistance value is finely adjusted when the second trimming grooves (12, 12A, 12B) are formed, thereby increasing the accuracy of the resistance value.

[0111] 1, 1A, 1B Chip resistor 2, 2A, 2B Insulating substrate (substrate) 3, 3A, 3B First top electrode (first electrode) 4, 4A, 4B Second top electrode (second electrode) 5, 5A, 5B Resistor 11, 11A, 11B First trimming groove 12, 12A, 12B Second trimming groove 13A Third trimming groove 21, 21A, 21B Surface (one surface) 51, 51A, 51B First edge 52, 52A, 52B Second edge 111, 111A, 111B First straight part 112, 112A, 112B Second straight part 113, 113A, 115B Tip 114B End 121, 121A, 121B Third straight section 122, 122A, 122B Fourth straight section 123, 123A, 123B Tip 131A Fifth straight section 132A Sixth straight section 133A Tip G1 Gap L1 Distance L2 Distance L3 Distance

Claims

a first electrode and a second electrode provided on both ends in a first direction of one surface of the substrate; a resistor provided between the first electrode and the second electrode on the one surface of the substrate, the resistor having a first edge and a second edge extending along the first direction; a first trimming groove formed in the resistor, the first trimming groove having a first linear portion extending linearly from the first edge to a tip along a second direction perpendicular to the first direction, and a second linear portion extending linearly from the tip of the first linear portion along the first direction; and a second trimming groove formed in the resistor, the second trimming groove having a third linear portion disposed on the second electrode side of the first linear portion and extending linearly from the first edge to the tip along the first linear portion, and a fourth linear portion disposed on the second edge side of the second linear portion and extending linearly from the tip of the third linear portion along the second linear portion, A chip resistor, wherein when viewed in the second direction, a tip of the second trimming groove that is furthest from the second electrode is positioned closer to the second electrode than a tip of the first trimming groove that is furthest from the second electrode.

2. The chip resistor as described in claim 1, wherein L2 / L1 is 0.3 or more and 0.7 or less, where L1 is the distance between the edge of the second electrode on the first electrode side when viewed in the second direction and the tip of the first trimming groove, and L2 is the distance between the edge of the second electrode and the tip of the second trimming groove when viewed in the second direction.

3. The chip resistor as described in claim 1, further comprising a third trimming groove formed in the resistor, the third trimming groove having: a fifth straight portion arranged on the second electrode side of the third straight portion and extending linearly from the first edge along the third straight portion to a tip; and a sixth straight portion arranged on the second edge side of the fourth straight portion and extending linearly from the tip of the fifth straight portion along the fourth straight portion, wherein the tip of the third trimming groove that is located farthest from the second electrode when viewed in the second direction is located on the second electrode side of the tip of the second trimming groove.

4. The chip resistor as described in claim 3, wherein L2 / L1 is 0.4 or more and 0.8 or less, and L3 / L1 is 0.1 or more and 0.5 or less, where L1 is the distance between the edge of the second electrode on the first electrode side when viewed in the second direction and the tip of the first trimming groove, L2 is the distance between the edge of the second electrode and the tip of the second trimming groove when viewed in the second direction, and L3 is the distance between the edge of the second electrode and the tip of the third trimming groove when viewed in the second direction.

5. A chip resistor as described in any one of claims 1 to 4, wherein the first trimming groove further has a tip portion extending from the tip of the second straight portion in a direction different from that of the second straight portion.

6. The chip resistor according to claim 5, wherein an end of the tip portion of the first trimming groove is positioned at a position spaced from the tip of the fourth straight portion in the first direction.

7. A method for manufacturing a semiconductor device, comprising the steps of: forming a first electrode and a second electrode on both ends in a first direction of one surface of a substrate; forming a resistor having a first edge and a second edge extending along the first direction between the first electrode and the second electrode on the one surface of the substrate; forming a first trimming groove in the resistor; and forming a second trimming groove in the resistor, wherein the first trimming groove has a first linear portion extending linearly from the first edge to a tip along a second direction perpendicular to the first direction, and a second linear portion extending linearly from the tip of the first linear portion along the first direction, and the second trimming groove has a third linear portion arranged on the second electrode side of the first linear portion and extending linearly from the first edge to the tip along the first linear portion, and a fourth linear portion arranged on the second edge side of the second linear portion and extending linearly from the tip of the third linear portion along the second linear portion, A method for manufacturing a chip resistor, wherein, when viewed in the second direction, a tip of the second trimming groove that is farthest from the second electrode is positioned closer to the second electrode than a tip of the first trimming groove that is farthest from the second electrode.

8. The method for manufacturing a chip resistor according to claim 7, wherein the step of forming the second trimming groove is performed after the step of forming the first trimming groove.

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