Resistor

Abstract

To provide a resistor capable of improving heat dissipation to a substrate.SOLUTION: A resistor (100) includes: a frame (10) including a resistive body (12) and a resin layer (11); a protective film (20); and a first electrode (30) and a second electrode (40). The resistive body (12) includes a surface (12a) and is buried in the resin layer such that the surface is exposed. The protective film is disposed over a central portion of the surface in a first direction (DR1). The first electrode is disposed over one end portion of the surface in the first direction and extends to reach over the protective film. The second electrode is disposed over the other end portion of the surface in the first direction and extends to reach over the protective film. A width (W2) of the resistor in a second direction (DR2) perpendicular to the first direction is wider than a width (W1) of the resistor in the first direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to resistors. [Background technology]

[0002] WO 2020 / 162266 (Patent Document 1) describes a resistor. The resistor described in Patent Document 1 has an insulating plate, a resistive element, a protective film, a first electrode, and a second electrode. The resistive element has a surface. The resistive element is embedded in the insulating plate so that the surface is exposed.

[0003] The protective film is disposed on the center of the surface of the resistor in the first direction. The first electrode and the second electrode are disposed on one end and the other end of the surface of the resistor in the first direction, respectively. Each of the first electrode and the second electrode extends to reach onto the protective film. The resistor described in Patent Document 1 has a smaller width in the second direction than in the first direction. The second direction is perpendicular to the first direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 162266 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, the resistor described in Patent Document 1 has a smaller width in the second direction than in the first direction. Therefore, the resistor described in Patent Document 1 has a small connection area with the substrate, and there is room for improvement in heat dissipation to the substrate. The present disclosure has been made in view of such problems in the conventional technology. More specifically, the present disclosure provides a resistor capable of improving heat dissipation to the substrate. [Means for solving the problem]

[0006] The resistor of the present disclosure includes a frame having a resistive element and a resin layer, a protective film, and a first electrode and a second electrode. The resistive element has a surface and is embedded in the resin layer so that the surface is exposed. The protective film is disposed on a center portion of the surface in a first direction. The first electrode is disposed on one end of the surface in the first direction and extends to reach onto the protective film. The second electrode is disposed on the other end of the surface in the first direction and extends to reach onto the protective film. The width of the resistor in a second direction perpendicular to the first direction is larger than the width of the resistor in the first direction. Effect of the Invention

[0007] The resistor of the present disclosure allows for improved heat dissipation to the substrate. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a bottom view of resistor 100. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 1 is a plan view of a resistor 100. [Figure 4] 2A to 2C are process diagrams showing a method for manufacturing the resistor 100. [Diagram 5] FIG. 11 is a bottom view illustrating the preparation step S1. [Figure 6] FIG. 11 is a bottom view illustrating the first underlayer forming step S2. [Figure 7] FIG. 11 is a bottom view illustrating a protective film forming step S3. [Figure 8] FIG. 11 is a bottom view illustrating the second underlayer forming step S4. [Figure 9] FIG. 11 is a cross-sectional view illustrating a first cutting step S5. [Figure 10] FIG. 11 is a bottom view illustrating the second cutting step S6. [Figure 11] FIG. 11 is a cross-sectional view illustrating a plating step S7. [Figure 12] FIG. 2 is a bottom view of resistor 100A. [Figure 13]FIG. 2 is a bottom view of resistor 200. [Figure 14] 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13. [Figure 15] FIG. 13 is a bottom view of a resistor 200 according to a modified example. [Figure 16] 13 is a bottom view illustrating a second underlayer forming step S4 in the method for manufacturing the resistor 200. FIG. [Figure 17] 13 is a bottom view illustrating a plating step S7 in the method for manufacturing the resistor 200. FIG. [Figure 18] FIG. 3 is a bottom view of resistor 300. [Figure 19] 19 is a cross-sectional view taken along line XIX-XIX in FIG. 18. [Figure 20] FIG. 3 is a plan view of resistor 300. [Figure 21] FIG. 4 is a bottom view of a resistor 300 according to a first modified example. [Figure 22] 11 is a cross-sectional view of a resistor 300 according to a second modification. FIG. [Figure 23] 3A to 3C are process diagrams showing a method for manufacturing a resistor 300. [Figure 24] FIG. 13 is a bottom view illustrating the preparation step S8. [Diagram 25] FIG. 11 is a bottom view illustrating a protective film forming step S9. [Figure 26] FIG. 11 is a bottom view illustrating the first plating step S10. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The details of the embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and redundant description will not be repeated.

[0010] (First embodiment) A resistor according to a first embodiment will be described. The resistor according to the first embodiment is designated as resistor 100.

[0011] <Configuration of resistor 100> The configuration of resistor 100 will now be described.

[0012] Fig. 1 is a bottom view of the resistor 100. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. Fig. 3 is a plan view of the resistor 100. As shown in Figs. 1 to 3, the resistor 100 has a frame 10, a protective film 20, an electrode 30, and an electrode 40.

[0013] The frame 10 has a resin layer 11 and a resistor 12. The resin layer 11 is made of a resin material. The resin layer 11 is made of, for example, glass epoxy. The resistor 12 is made of a metal material. The resistor 12 is made of, for example, a manganese-copper alloy, a copper-nickel alloy, a nickel-chromium alloy, or the like. The resistor 12 has a surface 12a. The resistor 12 is embedded in the resin layer 11 so that the surface 12a is exposed. The frame 10 is rectangular in plan view. The short and long sides of the rectangle are aligned along a first direction DR1 and a second direction DR2, respectively. The second direction DR2 is perpendicular to the first direction DR1.

[0014] Although not shown, a first slit and a second slit may be formed in the resistor 12 in order to adjust the resistance of the resistor 12. The first slit and the second slit penetrate the resistor 12 in the thickness direction. The first slit is formed at one end of the resistor 12 in the second direction DR2 and extends along the second direction DR2. The second slit is formed at the other end of the resistor 12 in the second direction DR2 and extends along the second direction DR2.

[0015] The protective film 20 is made of an electrically insulating material. The protective film 20 is made of, for example, an epoxy resin. The protective film 20 may contain a filler. The filler is made of, for example, a ceramic material such as alumina or boron nitride. The protective film 20 is disposed on the center of the surface 12a in the first direction DR1. The protective film 20 is not disposed on both ends of the surface 12a in the first direction DR1.

[0016] The electrode 30 has an underlayer 31, an underlayer 32, and a plating layer 33. The constituent material of the underlayer 31 is, for example, a conductive resin material. The conductive resin material includes a resin material and metal particles. The resin material is, for example, an epoxy resin. The constituent material of the metal particles is, for example, silver. The underlayer 31 is disposed on one end of the surface 12a in the first direction DR1. One end of the underlayer 31 in the first direction DR1 is spaced from the other end of the surface 12a in the first direction DR1. One end of the protective film 20 in the first direction DR1 is on the other end of the underlayer 31 in the first direction DR1.

[0017] The base layer 32 is made of, for example, a conductive resin material. The conductive resin material includes a resin material and metal particles. The resin material is, for example, an epoxy resin. The metal particles are made of, for example, silver. The base layer 32 is disposed on the base layer 31. The base layer 32 extends so as to reach the protective film 20. That is, the other end of the base layer 32 in the first direction DR1 is on the protective film 20.

[0018] The plating layer 33 is a layer formed by plating. The plating layer 33 has, for example, a copper layer, a nickel layer disposed on the copper layer, and a tin layer disposed on the nickel layer. The plating layer 33 is disposed on the underlayer 31 or the underlayer 32. However, a part of the plating layer 33 is disposed on the surface 12a. The other end of the plating layer 33 in the first direction DR1 may be disposed on the protective film 20. The plating layer 33 may also be disposed on a side surface of the frame 10 at one end in the first direction DR1.

[0019] The electrode 40 has an underlayer 41, an underlayer 42, and a plating layer 43. The constituent material of the underlayer 41 is, for example, a conductive resin material. The conductive resin material includes a resin material and metal particles. The resin material is, for example, an epoxy resin. The constituent material of the metal particles is, for example, silver. The underlayer 41 is disposed on the other end of the surface 12a in the first direction DR1. The other end of the underlayer 41 in the first direction DR1 is spaced apart from the other end of the surface 12a in the first direction DR1. The other end of the protective film 20 in the first direction DR1 is on one end of the underlayer 41 in the first direction DR1.

[0020] The base layer 42 is made of, for example, a conductive resin material. The conductive resin material includes a resin material and metal particles. The resin material is, for example, an epoxy resin. The metal particles are made of, for example, silver. The base layer 42 is disposed on the base layer 41. The base layer 42 extends so as to reach the protective film 20. That is, one end of the base layer 42 in the first direction DR1 is on the protective film 20.

[0021] The plating layer 43 is a layer formed by plating. The plating layer 43 has, for example, a copper layer, a nickel layer disposed on the copper layer, and a tin layer disposed on the nickel layer. The plating layer 43 is disposed on the underlayer 41 or on the underlayer 42. However, a part of the plating layer 43 is disposed on the surface 12a. One end of the plating layer 43 in the first direction DR1 may be disposed on the protective film 20. The plating layer 43 may also be disposed on a side surface of the frame 10 at the other end in the first direction DR1.

[0022] The width of the resistor 100 in the first direction DR1 is defined as width W1. The width of the resistor 100 in the second direction DR2 is defined as width W2. The width W2 is larger than the width W1. That is, the longitudinal direction of the resistor 100 is aligned with the second direction DR2. The width W2 is preferably 3.2 mm or less.

[0023] <Method of manufacturing resistor 100> A method for manufacturing resistor 100 will now be described.

[0024] Fig. 4 is a process diagram showing a method for manufacturing the resistor 100. As shown in Fig. 4, the method for manufacturing the resistor 100 includes a preparation step S1, a first underlayer forming step S2, a protective film forming step S3, a second underlayer forming step S4, a first cutting step S5, a second cutting step S6, and a plating step S7.

[0025] Fig. 5 is a bottom view illustrating the preparation step S1. As shown in Fig. 5, in the preparation step S1, a frame 50 is prepared. The frame 50 includes a plurality of frames 10. In Fig. 5, each of the plurality of frames 10 included in the frame 50 is delineated by a dotted line. After the preparation step S1, a first undercoat layer forming step S2 is performed.

[0026] FIG. 6 is a bottom view illustrating the first underlayer forming step S2. As shown in FIG. 6, in the first underlayer forming step S2, an underlayer 60 is formed. In the first underlayer forming step S2, first, a paste containing an uncured resin material and metal particles is applied. Second, the applied paste is heated to cure the resin material to form the underlayer 60. Note that the underlayers 60 each have an opening 60a. The surface 12a is exposed from the opening 60a. After the first underlayer forming step S2, a protective film forming step S3 is performed.

[0027] Fig. 7 is a bottom view illustrating the protective film forming step S3. As shown in Fig. 7, in the protective film forming step S3, the protective film 20 is formed. In the protective film forming step S3, first, a constituent material (uncured resin material) of the protective film 20 is applied. Second, the applied uncured resin material is heated and cured to become the protective film 20. After the protective film forming step S3, a second base layer forming step S4 is performed.

[0028] Fig. 8 is a bottom view illustrating the second undercoat layer forming step S4. As shown in Fig. 8, in the second undercoat layer forming step S4, undercoat layer 32 and undercoat layer 42 are formed. In the second undercoat layer forming step S4, first, a paste containing an uncured resin material and metal particles is applied. Second, the applied paste is heated to cure the resin material, thereby forming undercoat layer 32 and undercoat layer 42. After the second undercoat layer forming step S4, a first cutting step S5 is performed.

[0029] Fig. 9 is a cross-sectional view illustrating the first cutting step S5. As shown in Fig. 9, in the first cutting step S5, the frame 50 is cut along a cutting line CL1. The cutting line CL1 is along the second direction DR2. As the frame 50 is cut, the underlayer 60 is also separated into the underlayer 31 and the underlayer 41. After the first cutting step S5, a second cutting step S6 is performed.

[0030] Fig. 10 is a bottom view illustrating the second cutting step S6. As shown in Fig. 10, in the second cutting step S6, the frame 50 is cut along a cutting line CL2. The cutting line CL2 is aligned with the first direction DR1. As a result, the frame 50 is divided into a plurality of frames 10. After the second cutting step S6, a plating step S7 is performed.

[0031] Fig. 11 is a cross-sectional view illustrating the plating step S7. As shown in Fig. 11, in the plating step S7, a copper layer, a nickel layer, and a tin layer are successively formed by performing electrolytic barrel plating. In this manner, the structure of the resistor 100 shown in Figs. 1 to 3 is formed.

[0032] <Effect of resistor 100> The effects of the resistor 100 will be described below in comparison with a resistor according to a comparative example, which will be referred to as resistor 100A.

[0033] 12 is a bottom view of resistor 100A. As shown in FIG. 12, in resistor 100A, width W2 is smaller than width W1. Except for this, the configuration of resistor 100A is the same as that of resistor 100.

[0034] Resistor 100 and resistor 100A are soldered to the board at electrodes 30 and 40. In resistor 100, width W2 is larger than width W1, so that the connection area with the board is larger than that of resistor 100A when compared at the same size. Therefore, in resistor 100, heat generated in resistive element 12 is more easily dissipated from electrodes 30 and 40 to the board via the solder joints, and heat dissipation to the board is improved compared to resistor 100A.

[0035] To reduce the width W2 in the resistor 100 and resistor 100A, it is necessary to reduce the width of the resistor element 12 in the second direction DR2 in the frame 50. However, reducing the width of the resistor element 12 in the second direction DR2 reduces the rigidity of the frame 50, which reduces the handleability of the frame 50. This becomes more noticeable when the width W2 is 3.2 mm or less. In this regard, in the resistor 100, since the width W2 is larger than the width W1, it is possible to reduce the width W1 and achieve miniaturization without reducing the width W2. Therefore, the resistor 100 makes it possible to improve the handleability of the frame 50 during manufacturing.

[0036] Second embodiment A resistor according to the second embodiment will be described. The resistor according to the second embodiment is referred to as resistor 200. Here, differences from resistor 100 will be mainly described, and overlapping descriptions will not be repeated.

[0037] <Configuration of resistor 200> The configuration of resistor 200 will now be described.

[0038] Fig. 13 is a bottom view of the resistor 200. Fig. 14 is a cross-sectional view taken along line XIV-XIV in Fig. 13. As shown in Fig. 13 and Fig. 14, the resistor 200 has a frame 10, a protective film 20, an electrode 30, and an electrode 40. In this regard, the configuration of the resistor 200 is common to that of the resistor 100.

[0039] In the resistor 200, a recess 30a is formed at the end of the electrode 30 on the electrode 40 side (one end of the electrode 30 in the first direction DR1), and a recess 40a is formed at the end of the electrode 40 on the electrode 30 side (the other end of the electrode 40 in the first direction DR1). The protective film 20 is exposed from the recess 30a and the recess 40a. In this respect, the configuration of the resistor 200 differs from the configuration of the resistor 100.

[0040] The portion of the electrode 30 adjacent to the recess 30a in the second direction DR2 is the first portion 30b, and the portion of the electrode 30 adjacent to the recess 30a from the side opposite to the first portion 30b in the second direction DR2 is the second portion 30c. Also, the portion of the electrode 40 adjacent to the recess 40a in the second direction DR2 is the first portion 40b, and the portion of the electrode 40 adjacent to the recess 40a from the side opposite to the first portion 40b in the second direction DR2 is the second portion 40c.

[0041] The width of the first portion 30b in the second direction DR2 is, for example, larger than the width of the second portion 30c in the second direction DR2. The width of the first portion 40b in the second direction DR2 is, for example, larger than the width of the second portion 40c in the second direction DR2. In this case, the resistor 200 is used, for example, as a shunt resistor. That is, in this case, the resistor 200 can detect the current flowing between the first portion 30b and the first portion 40b by detecting the voltage between the second portion 30c and the second portion 40c in a state in which a current flows between the first portion 30b and the first portion 40b.

[0042] <Modification> In the above, an example in which the width W2 is greater than the width W1 has been described. Fig. 15 is a bottom view of a resistor 200 according to a modified example. As shown in Fig. 15, in the resistor 200, the width W2 may be smaller than the width W1.

[0043] <Method of Manufacturing Resistor 200> A method for manufacturing resistor 200 is described below.

[0044] The method for manufacturing the resistor 200 includes a preparation step S1, a first underlayer forming step S2, a protective film forming step S3, a second underlayer forming step S4, a first cutting step S5, a second cutting step S6, and a plating step S7. In this respect, the method for manufacturing the resistor 200 is common to the method for manufacturing the resistor 100.

[0045] FIG. 16 is a bottom view illustrating a second underlayer forming step S4 in the method for manufacturing the resistor 200. As shown in FIG. 16, in the second underlayer forming step S4 in the method for manufacturing the resistor 200, the underlayer 32 and the underlayer 42 are formed at intervals in the second direction DR2. FIG. 17 is a bottom view illustrating a plating step S7 in the method for manufacturing the resistor 200. The plating layer 33 cannot grow on the protective film 20 exposed between the adjacent underlayers 32, and the plating layer 44 cannot grow on the protective film 20 exposed between the adjacent underlayers 42. Therefore, in the method for manufacturing the resistor 200, the plating step S7 is performed, so that the recess 30a is formed in the electrode 30 and the recess 40a is formed in the electrode 40, as shown in FIG. 17. In these respects, the method for manufacturing the resistor 200 is different from the method for manufacturing the resistor 100.

[0046] <Effect of resistor 200> The effect of resistor 200 will be explained below.

[0047] In the resistor 200, the underlayer 32 and the underlayer 42 are formed at intervals along the second direction DR2 during the second underlayer formation step S4, so that the recesses 30a and the recesses 40a are formed in the electrodes 30 and 40, respectively. In this manner, the resistor 200 can be made into a four-terminal device without adding a new process, and can be used as, for example, a shunt resistor.

[0048] Third embodiment A resistor according to a third embodiment will be described. The resistor according to the third embodiment is referred to as resistor 300. Here, differences from resistor 200 will be mainly described, and overlapping descriptions will not be repeated.

[0049] <Configuration of resistor 300> The configuration of resistor 300 will now be described.

[0050] Fig. 18 is a bottom view of resistor 300. Fig. 19 is a cross-sectional view taken along line XIX-XIX in Fig. 18. Fig. 20 is a plan view of resistor 300. As shown in Figs. 18 to 20, resistor 300 has a frame 10, a protective film 20, an electrode 30 and an electrode 40. In this regard, the configuration of resistor 300 is common to that of resistor 200.

[0051] In resistor 300, frame 10 is composed of resistive element 12. The surface of resistive element 12 opposite surface 12a is referred to as surface 12b.

[0052] In the resistor 300, the electrode 30 has a plating layer 34, a plating layer 35, and a plating layer 35. The constituent materials of the plating layer 34, the plating layer 35, and the plating layer 35 are, for example, copper, nickel, and tin, respectively. The plating layer 34 is disposed on one end of the surface 12a in the first direction DR1. The plating layer 34 is also disposed on one end of the surface 12b in the first direction DR1. The plating layer 35 is disposed on the plating layer 34. The plating layer 35 is also disposed on a side surface of the resistor 12 at one end in the first direction DR1. The plating layer 36 is disposed on the plating layer 35.

[0053] In the resistor 300, the electrode 40 has a plating layer 44, a plating layer 45, and a plating layer 45. The constituent materials of the plating layer 44, the constituent materials of the plating layer 45, and the constituent materials of the plating layer 45 are, for example, copper, nickel, and tin, respectively. The plating layer 44 is disposed on the other end of the surface 12a in the first direction DR1. The plating layer 44 is also disposed on the other end of the surface 12b in the first direction DR1. The plating layer 45 is disposed on the plating layer 44. The plating layer 45 is also disposed on the side of the resistor 12 at the other end in the first direction DR1. The plating layer 46 is disposed on the plating layer 45.

[0054] In the resistor 300, the recess 30a reaches one end of the resistive element 12 in the first direction DR1, and the recess 40a reaches the other end of the resistive element 12 in the first direction DR1. In the resistor 300, the protective film 20 is disposed on the surface 12a exposed from the electrode 30 and the electrode 40. More specifically, the protective film 20 is disposed on the surface 12a between the electrode 30 and the electrode 40 in the first direction DR1 and on the surface 12a exposed from the recess 30a and the recess 40a.

[0055] The resistor 300 further includes a protective film 21. The constituent material of the protective film 21 is, for example, the same as the constituent material of the protective film 20. The protective film 21 is disposed on the surface 12b exposed from the electrode 30 and the electrode 40. In these respects, the configuration of the resistor 300 is common to the configuration of the resistor 200.

[0056] <First Modification> In the above, an example in which the width W2 is greater than the width W1 has been described. Fig. 21 is a bottom view of a resistor 300 according to a first modified example. As shown in Fig. 21, in the resistor 300, the width W2 may be smaller than the width W1.

[0057] <Second Modification> FIG. 22 is a cross-sectional view of a resistor 300 according to a second modification. As shown in FIG. 22, in the resistor 300, the electrode 30 may not have the plating layer 35, and the electrode 40 may not have the plating layer 45. In this case, the plating layer 34 is also disposed on the side surface of the resistor 12 at one end in the first direction DR1, and the plating layer 44 is also disposed on the side surface of the resistor 12 at the other end in the first direction DR1. In this case, the plating layer 36 and the plating layer 46 are disposed on the plating layer 34 and the plating layer 44, respectively. In the resistor 300, the plating layer 34 may not be disposed on one end of the surface 12b in the first direction DR1, and the plating layer 44 may not be disposed on the other end of the surface 12b in the first direction DR1. In this case, the protective film 21 is disposed on the entire surface of the surface 12b.

[0058] <Method of Manufacturing Resistor 300> A method for manufacturing resistor 300 will now be described.

[0059] Fig. 23 is a process diagram showing a manufacturing method of the resistor 300. As shown in Fig. 23, the manufacturing method of the resistor 300 includes a preparation step S8, a protective film forming step S9, a first plating step S10, a cutting step S11, and a second plating step S12.

[0060] Fig. 24 is a bottom view illustrating the preparation step S8. As shown in Fig. 24, in the preparation step S8, a frame 50 is prepared. The frame 50 includes a plurality of frames 10 (resistor elements 12). The plurality of resistor elements 12 included in the frame 50 are delineated by dotted lines in Fig. 24. After the preparation step S8, a protective film forming step S9 is performed.

[0061] FIG. 25 is a bottom view for explaining the protective film forming step S9. As shown in FIG. 25, in the protective film forming step S9, the protective film 20 is formed. The protective film 20 has a plurality of first straight line portions and a plurality of second straight line portions. Each of the plurality of first straight line portions extends along the first direction DR1. The plurality of first straight line portions are arranged at intervals in the second direction DR2. Each of the plurality of second straight line portions extends along the second direction DR2. The plurality of second straight line portions are arranged at intervals in the first direction DR1. The portion where the first straight line portion and the second straight line portion intersect is present at one location on the surface 12a of each of the plurality of resistors 12 included in the frame 50. The protective film 20 is formed by applying a constituent material (uncured resin material) of the protective film 20 and heating and curing the applied uncured resin material. Although not shown in the drawings, in the protective film forming step S9, the protective film 21 is also formed by the same method. After the protective film forming step S9, a first plating step S10 is performed.

[0062] Fig. 26 is a bottom view illustrating the first plating step S10. As shown in Fig. 26, in the first plating step S10, for example, rack plating is performed to form a plating layer 61 on the surface 12a exposed from the protective film 20. After the first plating step S10, a cutting step S11 is performed. In the cutting step S11, the frame 50 is cut to separate the resistor elements 12. As the frame 50 is cut, the plating layer 61 is separated into the plating layer 34 and the plating layer 42. After the cutting step S11, a second plating step S12 is performed.

[0063] In the second plating step S12, for example, barrel plating is performed to sequentially form plating layers 35 and 36, and also plating layers 45 and 46. Plating layers 35 and 36 grow only on plating layer 34, and do not grow on protective film 20. Similarly, plating layers 45 and 46 grow only on plating layer 44, and do not grow on protective film 20. In this manner, recesses 30a and 40a are formed in electrodes 30 and 40, respectively. As a result, resistor 300 having the structure shown in Figs. 18 to 20 is formed.

[0064] <Effect of resistor 300> The effect of resistor 300 will be explained below.

[0065] In the resistor 300, the protective film 20 is formed to have a plurality of first straight line portions and a plurality of second straight line portions during the protective film forming step S9, so that the recesses 30a and the recesses 40a are formed in the electrodes 30 and 40, respectively. In this manner, the resistor 300 can be made into a four-terminal device without adding a new process, and can be used as, for example, a shunt resistor.

[0066] (Additional Note) The above embodiment includes the following configurations.

[0067] <Appendix 1> A resistor, a frame having a resistor and a resin layer; A protective film; A first electrode and a second electrode, the resistor has a surface and is embedded in the resin layer such that the surface is exposed, the protective film is disposed on a central portion of the surface in a first direction; the first electrode is disposed on one end of the surface in the first direction and extends to reach the protective film; the second electrode is disposed on the other end of the surface in the first direction and extends to reach the protective film; A resistor, wherein a width of the resistor in a second direction perpendicular to the first direction is greater than a width of the resistor in the first direction.

[0068] <Appendix 2> 2. The resistor of claim 1, wherein the width of the resistor in the second direction is 3.2 mm or less.

[0069] <Appendix 3> A resistor, a frame having a resistor; A first electrode and a second electrode; A protective film is provided. The resistor has a surface, the first electrode is disposed on one end of the surface in a first direction; the second electrode is disposed on the other end of the surface in the first direction; a first recess and a second recess are formed at an end of the first electrode on the second electrode side and an end of the second electrode on the first electrode side, respectively; The protective film is disposed on at least the surface exposed from the first electrode and the second electrode.

[0070] <Appendix 4> 4. The resistor of claim 3, wherein a width of the resistor in a second direction perpendicular to the first direction is greater than a width of the resistor in the first direction.

[0071] <Appendix 5> 4. The resistor of claim 3, wherein a width of the resistor in the first direction is greater than a width of the resistor in a second direction perpendicular to the first direction.

[0072] <Appendix 6> The frame further has a resin layer, the resistor is embedded in the resin layer such that the surface is exposed, the protective film is disposed on a central portion of the surface in the first direction, 6. The resistor according to claim 3, wherein each of the first electrode and the second electrode extends onto the protective film.

[0073] <Appendix 7> the frame is made up of only the resistor, the first recess reaches one end of the resistor in the first direction, 6. The resistor according to claim 3, wherein the second recess reaches the other end of the resistor element in the first direction.

[0074] Although the embodiment of the present disclosure has been described above, the above-mentioned embodiment can be modified in various ways. The scope of the present invention is not limited to the above-mentioned embodiment. The scope of the present invention is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. [Explanation of symbols]

[0075] 10 frame, 11 resin layer, 12 resistor, 12a, 12b surface, 20, 21 protective film, 30 electrode, 30a recess, 30b first portion, 30c second portion, 31, 32 underlayer, 33, 34, 35, 36 plating layer, 40 electrode, 40a recess, 40b first portion, 40c second portion, 41, 42 underlayer, 43, 44, 45, 46 plating layer, 50 frame, 60 underlayer, 60a opening, 61 plating layer, 100, 100A, 200, 300 resistor, CL1, CL2 cutting line, DR1 first direction, DR2 second direction, S1 preparation step, S2 first underlayer forming step, S3 protective film forming step, S4 second underlayer forming step, S5 first cutting step, S6 Second cutting step, S7 plating step, S8 preparation step, S9 protective film forming step, S10 first plating step, S11 cutting step, S12 second plating step, W1, W2 width.

Claims

1. A resistor, a frame having a resistor and a resin layer; A protective film; A first electrode and a second electrode, the resistor has a surface and is embedded in the resin layer such that the surface is exposed, the protective film is disposed on a central portion of the surface in a first direction; the first electrode is disposed on one end of the surface in the first direction and extends to reach the protective film; the second electrode is disposed on the other end of the surface in the first direction and extends to reach the protective film; A resistor, wherein a width of the resistor in a second direction perpendicular to the first direction is greater than a width of the resistor in the first direction.

2. The resistor of claim 1 , wherein the width of the resistor in the second direction is less than or equal to 3.2 mm.

3. A resistor, a frame having a resistor; A first electrode and a second electrode; A protective film is provided. The resistor has a surface, the first electrode is disposed on one end of the surface in a first direction; the second electrode is disposed on the other end of the surface in the first direction; a first recess and a second recess are formed at an end of the first electrode on the second electrode side and an end of the second electrode on the first electrode side, respectively; The protective film is disposed on at least the surface exposed from the first electrode and the second electrode.

4. The resistor of claim 3 , wherein a width of the resistor in a second direction perpendicular to the first direction is greater than a width of the resistor in the first direction.

5. The resistor of claim 3 , wherein a width of the resistor in the first direction is greater than a width of the resistor in a second direction perpendicular to the first direction.

6. The frame further has a resin layer, the resistor is embedded in the resin layer such that the surface is exposed, the protective film is disposed on a central portion of the surface in the first direction, The resistor according to claim 3 , wherein each of the first electrode and the second electrode extends so as to reach onto the protective film.

7. the frame is made up of only the resistor, the first recess reaches one end of the resistor in the first direction, The resistor according to claim 3 , wherein the second recess reaches the other end of the resistor element in the first direction.

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