Electronic component
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MURATA MFG CO LTD
- Filing Date
- 2025-12-16
- Publication Date
- 2026-07-02
Smart Images
Figure JP2025043955_02072026_PF_FP_ABST
Abstract
Description
Electronic component
[0001] This disclosure relates to an electronic component.
[0002] Patent Document 1 discloses an oscillation prevention circuit. The oscillation prevention circuit of Patent Document 1 includes two wiring patterns, a capacitor, a resistance layer, and a connection conductor. The resistance layer is formed on an insulating substrate. The two wiring patterns are formed on the resistance layer so as to extend on the same straight line with a gap therebetween. The capacitor includes an upper electrode layer and a lower electrode layer. The capacitor is mounted on one of the two wiring patterns. Specifically, the lower electrode layer of the capacitor is laminated on one of the two wiring patterns. The connection conductor is a bonding wire, and the upper electrode layer of the capacitor and the other of the two wiring patterns are connected to each other by wire bonding.
[0003] Japanese Patent Application Laid-Open No. 2013-98339
[0004] However, in the structure of an electronic component such as the oscillation prevention circuit of Patent Document 1, a part of the resistance layer is exposed to the outside. As a result, problems such as oxidation of a part of the resistance layer may occur.
[0005] This disclosure has been made in view of the above problems, and an object thereof is to provide an electronic component in which problems are less likely to occur.
[0006] The electronic component according to this disclosure has a base material, a first part, and a second part that is located on the first direction side with respect to the first part and is connected to the first part, a resistance layer formed on the base material, a base material electrode part having an edge on the first direction side and formed on the first part, a first covering part that covers the second part, and a second covering part that is located on the second direction side opposite to the first direction side with respect to the first covering part and is connected to the first covering part, a protective film in which the second covering part covers the edge, a chip part having a chip electrode part, and solder that fixes the chip part to the base material electrode part on the second direction side of the second covering part and electrically connects the chip electrode part and the base material electrode part.
[0007] According to the electronic component according to this disclosure, problems are less likely to occur.
[0008] This is a plan view of an electronic component according to an embodiment of the present disclosure. This is a cross-sectional view along line II-II in Figure 1. This is an enlarged cross-sectional view showing a part of an electronic component according to an embodiment of the present disclosure. This is a plan view showing a part of an electronic component according to an embodiment of the present disclosure. This is a cross-sectional view showing a modified example of an electronic component according to an embodiment of the present disclosure. This is a photograph of a cross-section of an electronic component according to an embodiment.
[0009] Hereinafter, embodiments relating to the electronic components of this disclosure will be described with reference to Figures 1 to 5, and an example relating to the electronic components of this disclosure will be described with reference to Figure 6. However, this disclosure is not limited to the embodiments and examples described below, and can be implemented in various forms without departing from its gist. In addition, explanations may be omitted where necessary to avoid repetition. Furthermore, in the figures, the same or corresponding parts will be denoted by the same reference numerals and will not be repeated in the explanation.
[0010] For convenience, this specification defines mutually orthogonal X, Y, and Z axes to describe embodiments of the present disclosure. Specifically, as shown in Figure 1, the X-axis direction is defined as the direction in which the chip component 80 is positioned relative to the protective film 70, and the direction in which the protective film 70 is positioned relative to the chip component 80, and the direction in which the protective film 70 is positioned relative to the chip component 80, and the X-axis direction is defined as the direction in which the chip component 80 is positioned, and the Y-axis direction is defined as the direction in which the chip component 80 is positioned relative to the fourth coating portion 74 of the protective film 70, and the direction in which the fourth coating portion 74 of the protective film 70 is positioned relative to the chip component 80, and the Y-axis direction is defined as the direction in which the Z-axis direction is defined as the direction in which the resistive layer 20 is positioned relative to the substrate 10, and the direction in which the substrate 10 is positioned relative to the resistive layer 20, and the Z-axis direction is defined as the direction in which the Z-axis direction is defined, and the Z-axis direction is defined as the direction in which the resistive layer 20 is positioned, and the Z-axis direction is defined as the direction in which the resistive layer 20 is positioned, and the Z-axis direction is defined as the direction in which the electronic components of this disclosure are positioned, and the X-axis direction, Y-axis direction, and Z-axis direction are defined here for convenience of explanation and do not specify the orientation during manufacturing or use.
[0011] Figure 1 is a plan view of the electronic component 100 of this embodiment. Figure 2 is a cross-sectional view along the line II-II in Figure 1. As shown in Figure 1, the electronic component 100 comprises a substrate 10, a resistive layer 20, a first substrate electrode portion 30, a second substrate electrode portion 40, a third substrate electrode portion 50, a via 60, a protective film 70, a chip component 80, a first solder 91, and a second solder 92.
[0012] The base material 10 is a flat plate-shaped member that extends along the XY plane. In this embodiment, the base material 10 is rectangular. The base material 10 may also be a ceramic substrate. The material of the base material 10 is, for example, aluminum nitride.
[0013] The substrate 10 has a main surface 11. The main surface 11 is the +Z side surface of the substrate 10, as shown in Figure 2. In this specification, the +Z direction is defined as the upward direction and the -Z direction as the downward direction. Therefore, the main surface 11 of the substrate 10 is the upper surface of the substrate 10. However, the upward and downward directions here are defined for the convenience of explanation and do not specify the orientation of the electronic component during manufacturing or use according to this disclosure.
[0014] The first substrate electrode portion 30, the second substrate electrode portion 40, and the third substrate electrode portion 50 are formed on the upper surface of the resistive layer 20, which will be described later with reference to Figure 2. The first substrate electrode portion 30 functions as an electrode of the substrate 10. The first substrate electrode portion 30 may be formed by, for example, plating. More specifically, the first substrate electrode portion 30 may have a lower layer and an upper layer formed by plating on the upper surface of the lower layer. The lower layer of the first substrate electrode portion 30 may be, for example, a NiCr-Pd vapor-deposited film. The upper layer of the first substrate electrode portion 30 may be, for example, a NiPdAu plated film. The second substrate electrode portion 40 and the third substrate electrode portion 50 also function as electrodes of the substrate 10, similar to the first substrate electrode portion 30. The second substrate electrode portion 40 and the third substrate electrode portion 50 may also be formed by, for example, plating, similar to the first substrate electrode portion 30.
[0015] The chip component 80 has a first chip electrode portion 81 and a second chip electrode portion 82. The first chip electrode portion 81 and the second chip electrode portion 82 are aligned in the direction of the X-axis. In this embodiment, the first chip electrode portion 81 and the second chip electrode portion 82 are aligned in this order in the -X direction (second direction D2, which will be described later). Specifically, the chip component 80 may be a capacitor. For example, the chip component 80 may be a multilayer ceramic capacitor. If the chip component 80 is a capacitor, the electronic component 100 may be, for example, a component that constitutes an RC circuit.
[0016] The first solder 91 bonds the chip component 80 to the first substrate electrode portion 30, electrically connecting the first chip electrode portion 81 and the first substrate electrode portion 30. The second solder 92 bonds the chip component 80 to the third substrate electrode portion 50, electrically connecting the second chip electrode portion 82 and the third substrate electrode portion 50.
[0017] In this embodiment, the electronic component 100 is mounted on another electronic circuit board. The second substrate electrode portion 40 functions as an electrode for electrically connecting the electronic component 100 to the other electronic circuit board. Specifically, one end of a bonding wire is joined to the second substrate electrode portion 40. In other words, the second substrate electrode portion 40 functions as an electrode for wire bonding with the other electronic circuit board.
[0018] The third substrate electrode portion 50 has an exposed portion 51. The exposed portion 51 is the area of the third substrate electrode portion 50 that is not covered by the chip component 80. The via 60 penetrates the exposed portion 51 of the third substrate electrode portion 50, the resistive layer 20 (see Figure 2), and the substrate 10 in the vertical direction (Z-axis direction). The via 60 electrically connects the third substrate electrode portion 50 to other electronic circuit boards.
[0019] As shown in Figure 2, the resistive layer 20 is formed on the main surface 11 of the substrate 10. More specifically, the resistive layer 20 is formed below the first substrate electrode portion 30, the second substrate electrode portion 40, the third substrate electrode portion 50 (see Figure 1), and the protective film 70. The resistive layer 20 is, for example, a thin-film resistor. The material of the resistive layer 20 is, for example, tantalum nitride.
[0020] More specifically, the resistive layer 20 has a first portion 21, a second portion 22, and a third portion 23. The second portion 22 is located on the first direction D1 side relative to the first portion 21 and is connected to the first portion 21. The third portion 23 is located on the first direction D1 side relative to the second portion 22 and is connected to the second portion 22. Here, the first direction D1 is parallel to the +X direction. The first portion 21, the second portion 22, and the third portion 23 each constitute a part of the resistive layer 20.
[0021] The first substrate electrode portion 30 is formed on the upper surface of the first portion 21 of the resistive layer 20. The first substrate electrode portion 30 also has an edge portion 311. The edge portion 311 is the edge portion of the first substrate electrode portion 30 on the first direction D1 side (+X side). More specifically, the first substrate electrode portion 30 has an electrode body 31. The electrode body 31 extends along the first portion 21 of the resistive layer 20. The edge portion 311 is included in the electrode body 31. In other words, the edge portion 311 is the edge portion of the electrode body 31 on the first direction D1 side (+X side).
[0022] The second substrate electrode portion 40 is formed on the upper surface of the third portion 23 of the resistive layer 20. The second substrate electrode portion 40 has an edge portion 411. The edge portion 411 is the edge portion of the second substrate electrode portion 40 on the second direction D2 side. The second direction D2 is the opposite direction to the first direction D1. In other words, the second direction D2 is parallel to the -X direction. More specifically, the second substrate electrode portion 40 has an electrode body 41. The electrode body 41 extends along the third portion 23 of the resistive layer 20. The edge portion 411 is included in the electrode body 41. In other words, the edge portion 411 is the edge portion of the electrode body 41 on the second direction D2 side (-X side).
[0023] The protective film 70 has a first coating portion 71 and a second coating portion 72. Specifically, the protective film 70 may be solder resist. For example, the protective film 70 may be a polyimide film. The first coating portion 71 and the second coating portion 72 each constitute a part of the protective film 70.
[0024] The first coating portion 71 covers the second portion 22 of the resistive layer 20. More specifically, the second portion 22 of the resistive layer 20 is located between the first substrate electrode portion 30 and the second substrate electrode portion 40. Therefore, the second portion 22 of the resistive layer 20 is exposed to the outside in the region between the first substrate electrode portion 30 and the second substrate electrode portion 40. The first coating portion 71 covers the portion of the resistive layer 20 that is exposed in the region between the first substrate electrode portion 30 and the second substrate electrode portion 40 (the second portion 22). Therefore, according to this embodiment, since the second portion 22 of the resistive layer 20 is covered by the protective film 70 (first coating portion 71), problems such as oxidation of the second portion 22 of the resistive layer 20 are less likely to occur.
[0025] The second covering portion 72 is located on the second direction D2 side relative to the first covering portion 71 and is connected to the first covering portion 71. The second covering portion 72 covers the edge portion 311 of the first base electrode portion 30.
[0026] The first solder 91 joins the chip component 80 and the first substrate electrode portion 30 on the second direction D2 side of the second coating portion 72. Therefore, the chip component 80 is fixed to the first substrate electrode portion 30 on the second direction D2 side of the second coating portion 72.
[0027] In this embodiment, since the second covering portion 72 covers the edge portion 311 of the first substrate electrode portion 30, the first substrate electrode portion 30 is less likely to peel off from the resistance layer 20. Specifically, in a structure in which the wall portion 32 described later is not provided and the first solder 91 extends to contact the end face of the protective film 70 on the second direction D2 side (-X side), if the second covering portion 72 is not provided, that is, if the edge portion 311 of the first substrate electrode portion 30 is not covered by the protective film 70, the bond between the protective film 70 (solder resist) and the solder is weak, so stress is applied to the chip component 80, causing the end of the first solder 91 to peel off from the protective film 70, and there is a risk that the end of the first substrate electrode portion 30 will peel off from the resistance layer 20 together with the end of the first solder 91. In contrast, in this embodiment, the edge portion 311 of the first substrate electrode portion 30 is covered by the protective film 70 (second covering portion 72). Therefore, since the edge portion 311 of the first substrate electrode portion 30 is pressed down from above by the protective film 70, the first substrate electrode portion 30 is less likely to peel off from the resistance layer 20.
[0028] Next, with reference to Figure 2, the electronic component 100 of this embodiment will be further described. As shown in Figure 2, the first substrate electrode portion 30 further has a wall portion 32 that protrudes upward (+Z direction) from the electrode body 31. The wall portion 32 is typically integrated with the electrode body 31. In other words, the wall portion 32 constitutes a part of the first substrate electrode portion 30. The wall portion 32 is interposed between the second coating portion 72 and the first solder 91. Therefore, even if a gap occurs between the protective film 70 and the resistive layer 20 during reflow, the distance from the soldering location to that gap is longer compared to a structure without the wall portion 32. As a result, solder is less likely to flow into that gap.
[0029] More specifically, a gap may occur between the protective film 70 and the first substrate electrode portion 30 during reflow due to the difference in thermal expansion coefficients between the protective film 70 (solder resist) and the first substrate electrode portion 30. Similarly, a gap may occur between the protective film 70 and the resistance layer 20 during reflow due to the difference in thermal expansion coefficients between the protective film 70 (solder resist) and the resistance layer 20. As a result, in the case of a structure without a wall portion 32, solder may flow into the gap between the protective film 70 and the resistance layer 20 through the gap between the protective film 70 and the first substrate electrode portion 30 during reflow. Then, the flow of solder into the gap between the protective film 70 and the resistance layer 20 may cause the protective film 70 to peel off from the resistance layer 20. In contrast, according to this embodiment, even if a gap occurs between the protective film 70 and the resistance layer 20 during reflow, solder is less likely to flow into that gap, making it difficult for the protective film 70 to peel off from the resistance layer 20.
[0030] Furthermore, if solder flows between the protective film 70 and the resistive layer 20, the solder may bond to the resistive layer 20, potentially changing its resistance. In contrast, according to this embodiment, even if a gap occurs between the protective film 70 and the resistive layer 20 during reflow soldering, solder is less likely to flow into that gap, thus preventing a change in the resistance of the resistive layer 20.
[0031] Furthermore, if the protective film 70 peels off from the resistive layer 20, the edge 311 of the first substrate electrode portion 30 may no longer be held in place by the protective film 70 (second coating portion 72). Consequently, the first substrate electrode portion 30 may peel off from the resistive layer 20. In contrast, according to this embodiment, since the protective film 70 is difficult to peel off from the resistive layer 20, the structure in which the edge 311 of the first substrate electrode portion 30 is held in place by the protective film 70 (second coating portion 72) can be maintained. Consequently, the first substrate electrode portion 30 is difficult to peel off from the resistive layer 20.
[0032] Next, the electronic component 100 of this embodiment will be described with reference to Figure 3. Figure 3 is an enlarged cross-sectional view showing a part of the electronic component 100 of this embodiment. More specifically, Figure 3 shows an enlarged view of the wall portion 32 and its surrounding area. Note that in Figure 3, the base material 10 is omitted for ease of understanding.
[0033] As shown in Figure 3, the wall portion 32 has a first surface 321 and a second surface 322. The first surface 321 is the surface of the wall portion 32 on the second direction D2 side (-X side). In other words, the first surface 321 is the surface on the first solder 91 side. The first solder 91 may be in contact with the first surface 321 of the wall portion 32. The second surface 322 is the surface of the wall portion 32 on the first direction D1 side (+X side). In other words, the second surface 322 is the surface on the protective film 70 side. The second covering portion 72 of the protective film 70 may be in contact with the second surface 322 of the wall portion 32. Hereinafter, the first surface 321 may be referred to as the "solder side surface 321". Also, the second surface 322 may be referred to as the "protective film side surface 322".
[0034] The solder side surface 321 has a first base end 32a and a tip end 32b. The first base end 32a is the lower end of the solder side surface 321. The first base end 32a indicates the point where the solder side surface 321 and the electrode body 31 are connected. The tip end 32b is the upper end of the solder side surface 321. The solder side surface 321 extends upward (in the +Z direction) from the first base end 32a to the tip end 32b.
[0035] In this embodiment, the length L1 from the first base end 32a to the tip end 32b of the solder side surface 321 is longer than the length L2 of the wall portion 32 in the X-axis direction (first direction D1 and second direction D2). Specifically, the wall portion 32 has a bottom surface 323. The bottom surface 323 connects to the electrode body 31. In other words, the bottom surface 323 is the interface between the wall portion 32 and the electrode body 31. Length L2 indicates the length from the first base end 32a to the second base end 32c of the bottom surface 323. The second base end 32c is the base end of the protective film side surface 322. Therefore, the second base end 32c is the lower end of the protective film side surface 322. The second base end 32c indicates the location where the protective film side surface 322 and the electrode body 31 connect. The protective film side surface 322 extends upward (+Z direction) from the second base end 32c.
[0036] As described above with reference to Figure 3, according to this embodiment, the length L1 from the first base end 32a to the tip end 32b of the solder side surface 321 is longer than the length L2 of the wall portion 32 in the X-axis direction (first direction D1 and second direction D2). Therefore, compared to a configuration without the wall portion 32, the contact area between the first base electrode portion 30 and the first solder 91 can be increased. Accordingly, according to this embodiment, the chip component 80 can be firmly joined to the first base electrode portion 30.
[0037] In this embodiment, the solder side surface 321 is a flat surface, but the solder side surface 321 may also be a curved surface.
[0038] Next, with reference to Figure 3, the electronic component 100 of this embodiment will be further described. As shown in Figure 3, in this embodiment, the height h1 of the second coating portion 72 from the resistance layer 20 is higher than the height h2 of the wall portion 32 from the resistance layer 20. Therefore, according to this embodiment, solder is less likely to flow out to the protective film 70 side during reflow. As a result, it is possible to suppress the first solder 91 from overflowing onto the upper surface of the protective film 70. In addition, it is possible to suppress the solder from flowing out to the outside of the protective film 70 during reflow, preventing the first solder 91 from overflowing onto the outside of the protective film 70.
[0039] In more detail, because solder is more easily wetted by the plating (wall portion 32) than by the solder resist (protective film 70), if the height h2 of the wall portion 32 from the resistance layer 20 is higher than the height h1 of the second coating portion 72 from the resistance layer 20, there is a risk that the solder will flow over the wall portion 32 and into the protective film 70. In contrast, according to this embodiment, since the height h1 of the second coating portion 72 from the resistance layer 20 is higher than the height h2 of the wall portion 32 from the resistance layer 20, the flow of solder can be blocked by the end face of the second coating portion 72 on the second direction D2 side (-X side). Therefore, during reflow, it becomes difficult for the solder to flow into the protective film 70.
[0040] Next, with reference to Figure 1, the electronic component 100 of this embodiment will be further described. As shown in Figure 1, the protective film 70 further has a third covering portion 73. In this embodiment, the protective film 70 has two third covering portions 73. Each of the two third covering portions 73 constitutes a part of the protective film 70.
[0041] The third covering portion 73 covers a part of the main surface 11 of the base material 10. In the present embodiment, one of the two third covering portions 73 extends in the +Y direction from the +Y side end of the resistance layer 20 to cover a part of the main surface 11 of the base material 10. The other of the two third covering portions 73 extends in the -Y direction from the -Y side end of the resistance layer 20 to cover another part of the main surface 11 of the base material 10. Therefore, both end portions in the Y-axis direction of the protective film 70 are joined to the main surface 11 of the base material 10. As a result, the problem that the first base material electrode portion 30 peels off from the resistance layer 20 can be further suppressed by the bonding force between the third covering portion 73 (protective film 70) and the base material 10.
[0042] Next, referring to FIGS. 1 and 4, the electronic component 100 of the present embodiment will be further described. FIG. 4 is a plan view showing a part of the electronic component 100 of the present embodiment. In FIG. 4, for ease of understanding, the base material 10 and the protective film 70 are omitted.
[0043] As shown in FIG. 4, the length WDL1 in the width direction WD of the first base material electrode portion 30 is longer than the length WDL2 in the width direction WD of the chip component 80. Here, the width direction WD is a direction parallel to the Y-axis direction. In other words, the width direction WD indicates a direction orthogonal to the X-axis direction (the first direction D1 and the second direction D2).
[0044] As shown in FIG. 4, the first base material electrode portion 30 has an exposed portion 33 that does not overlap the chip component 80 on one side in the width direction WD. The exposed portion 33 is a part of the electrode main body 31. In the present embodiment, the exposed portion 33 is provided on the -Y side of the chip component 80.
[0045] As shown in FIG. 1, the protective film 70 further has a fourth covering portion 74. The fourth covering portion 74 extends in the second direction D2 (-X direction) from the second covering portion 72 described with reference to FIG. 2 to cover a part of the exposed portion 33. The fourth covering portion 74 maintains the posture in which the second covering portion 72 presses the edge portion 311 of the first base material electrode portion 30. Therefore, it becomes even more difficult for the first base material electrode portion 30 to peel off from the resistance layer 20.
[0046] In this embodiment, the fourth covering portion 74 further extends from the exposed portion 33 in the second direction D2 (-X direction) and joins the main surface 11 of the base material 10. Therefore, similar to the third covering portion 73, the bonding force between the fourth covering portion 74 and the base material 10 can further suppress the problem that the first base electrode portion 30 peels off from the resistance layer 20.
[0047] Subsequently, referring to FIG. 1, the electronic component 100 of this embodiment will be further described. As shown in FIG. 1, the center line CL1 of the chip component 80 is located on the other side in the width direction WD with respect to the center line CL2 of the first base electrode portion 30. In this embodiment, the center line CL1 of the chip component 80 is located on the +Y side of the center line CL2 of the first base electrode portion 30. Note that the center line CL1 indicates the center in the width direction WD of the chip component 80. The center line CL2 indicates the center in the width direction WD of the first base electrode portion 30. Both the center lines CL1 and CL2 extend in the X-axis direction (the first direction D1 and the second direction D2).
[0048] According to this embodiment, since the center line CL1 of the chip component 80 is located on the +Y side of the center line CL2 of the first base electrode portion 30, even if the length in the width direction WD of the first base electrode portion 30 is not increased, a space for providing the fourth covering portion 74 can be secured. Therefore, the length in the width direction WD of the first base electrode portion 30 can be suppressed, and an increase in the dimensions of the electronic component 100 can be suppressed.
[0049] Subsequently, referring to FIG. 2, the electronic component 100 of this embodiment will be further described. As already described, the second base electrode portion 40 has an edge portion 411. In this embodiment, as shown in FIG. 2, the protective film 70 further has a fifth covering portion 75.
[0050] The fifth covering portion 75 is located on the first direction D1 side with respect to the first covering portion 71 and is connected to the first covering portion 71. Similar to the second covering portion 72, the fifth covering portion 75 covers the edge portion 411 of the second base electrode portion 40. Therefore, similar to the first base electrode portion 30, the second base electrode portion 40 is difficult to peel off from the resistance layer 20.
[0051] Next, a modified example of the electronic component 100 of this embodiment will be described with reference to Figure 5. Figure 5 is a cross-sectional view showing a modified example of the electronic component 100 of this embodiment. As shown in Figure 5, the surface 721 of the second coating portion 72 on the edge portion 311 side may be an inclined surface. Specifically, the surface 721 of the second coating portion 72 on the edge portion 311 side may be inclined to move away from the resistive layer 20 as it moves from the first coating portion 71 toward the second direction D2 side (-X side). Here, the surface 721 of the second coating portion 72 on the edge portion 311 side refers to the -Z side (lower side) of the second coating portion 72. Hereinafter, the surface 721 of the second coating portion 72 on the edge portion 311 side may be referred to as the "edge side surface 721".
[0052] According to the modified example shown in Figure 5, the length L3 of the edge side surface 721 in the X-axis direction (first direction D1 and second direction D2) can be increased by forming the protective film 70 such that the edge side surface 721 becomes an inclined surface. As a result, the edge 311 of the first substrate electrode portion 30 is formed to penetrate deeply into the inside of the protective film 70 (second covering portion 72). Therefore, the area of the portion of the first substrate electrode portion 30 covered by the protective film 70 increases, making it more difficult for the first substrate electrode portion 30 to peel off from the resistance layer 20.
[0053] As explained with reference to Figure 2, in this embodiment, the protective film 70 has a fifth covering portion 75. The surface of the fifth covering portion 75 on the edge 411 side may be inclined to move away from the resistive layer 20 as it moves from the first covering portion 71 toward the first direction D1 (+X side), similar to the second covering portion 72 shown in Figure 5. By inclining the surface of the fifth covering portion 75 on the edge 411 side to move away from the resistive layer 20 as it moves from the first covering portion 71 toward the first direction D1, the second substrate electrode portion 40 becomes less likely to peel off from the resistive layer 20.
[0054] As described above with reference to the drawings (Figures 1 to 5), the electronic component 100 of this embodiment comprises a substrate 10, a resistive layer 20, a first substrate electrode portion 30, a protective film 70, a chip component 80, and a first solder 91. The resistive layer 20 is formed on the substrate 10. The resistive layer 20 has a first portion 21 and a second portion 22. The second portion 22 is located on the first direction D1 side relative to the first portion 21 and is connected to the first portion 21. The first substrate electrode portion 30 is formed on the first portion 21 of the resistive layer 20. The first substrate electrode portion 30 has an edge portion 311 on the first direction D1 side. The protective film 70 has a first covering portion 71 and a second covering portion 72. The first covering portion 71 covers the second portion 22 of the resistive layer 20. The second covering portion 72 is located on the second direction D2 side, opposite to the first direction D1 side, relative to the first covering portion 71, and is connected to the first covering portion 71. The second covering portion 72 covers the edge portion 311 of the first substrate electrode portion 30. The chip component 80 has a first chip electrode portion 81. The first solder 91 fixes the chip component 80 to the first substrate electrode portion 30 on the second direction D2 side of the second covering portion 72, and electrically connects the first chip electrode portion 81 and the first substrate electrode portion 30.
[0055] As described above, according to this embodiment, since the second portion 22 of the resistive layer 20 is covered by the protective film 70 (first coating portion 71), problems such as oxidation of the second portion 22 of the resistive layer 20 are less likely to occur. Furthermore, according to this embodiment, since the second coating portion 72 covers the edge portion 311 of the first substrate electrode portion 30, the first substrate electrode portion 30 is less likely to peel off from the resistive layer 20.
[0056] Furthermore, according to this embodiment, the first substrate electrode portion 30 has an electrode body 31 that extends along the first portion 21 of the resistive layer 20, and a wall portion 32 that protrudes from the electrode body 31. The wall portion 32 is interposed between the second coating portion 72 and the first solder 91. Therefore, according to this embodiment, even if a gap occurs between the protective film 70 and the resistive layer 20 during reflow, the distance from the soldering location to the gap is longer compared to a structure without the wall portion 32. As a result, solder is less likely to flow into the gap between the protective film 70 and the resistive layer 20. Thus, the resistance value of the resistive layer 20 is less likely to change. Moreover, because solder is less likely to flow into the gap between the protective film 70 and the resistive layer 20, the protective film 70 is less likely to peel off from the resistive layer 20. Therefore, it is possible to maintain a structure in which the edge portion 311 of the first substrate electrode portion 30 is held down by the protective film 70 (second coating portion 72). Therefore, the first substrate electrode portion 30 is less likely to peel off from the resistive layer 20.
[0057] Furthermore, according to this embodiment, the length L1 from the first base end 32a to the tip end 32b of the solder side surface 321 (the side facing the first solder 91) of the wall portion 32 is longer than the length L2 of the wall portion 32 in the first direction D1. Here, the first base end 32a indicates the point where the solder side surface 321 of the wall portion 32 and the electrode body 31 are connected. Therefore, according to this embodiment, the contact area between the first base electrode portion 30 and the first solder 91 can be increased compared to a configuration without the wall portion 32. Thus, the chip component 80 can be more firmly bonded to the first base electrode portion 30.
[0058] Furthermore, according to this embodiment, the height h1 of the second coating portion 72 from the resistance layer 20 is higher than the height h2 of the wall portion 32 from the resistance layer 20. Therefore, according to this embodiment, solder is less likely to flow out to the protective film 70 side during reflow. As a result, it is possible to suppress the first solder 91 from overflowing onto the upper surface of the protective film 70 or overflowing onto the outside of the protective film 70.
[0059] Furthermore, according to this embodiment, the protective film 70 further has a third covering portion 73 that covers the substrate 10. Therefore, according to this embodiment, the bonding force between the third covering portion 73 (protective film 70) and the substrate 10 can further suppress the problem of the first substrate electrode portion 30 peeling off from the resistance layer 20.
[0060] Furthermore, according to this embodiment, the length WDL1 of the width direction WD perpendicular to the first direction D1 of the first substrate electrode portion 30 is longer than the length WDL2 of the width direction WD of the chip component 80. Also, the first substrate electrode portion 30 has an exposed portion 33 on one side (-Y side) of the width direction WD that does not overlap with the chip component 80. The protective film 70 further has a fourth covering portion 74 that extends from the second covering portion 72 in the second direction D2 and covers a part of the exposed portion 33. Therefore, according to this embodiment, the first substrate electrode portion 30 becomes even more difficult to peel off from the resistive layer 20.
[0061] Furthermore, according to this embodiment, the center line CL1 extending in the first direction D1 of the chip component 80 is located on the other side (+Y side) of the width direction WD relative to the center line CL2 extending in the first direction D1 of the first substrate electrode portion 30. Therefore, according to this embodiment, space for providing the fourth coating portion 74 can be secured without increasing the length of the width direction WD of the first substrate electrode portion 30. Thus, the length of the width direction WD of the first substrate electrode portion 30 can be suppressed, and the increase in the dimensions of the electronic component 100 can be suppressed.
[0062] Furthermore, according to this embodiment, the chip component 80 further has a second chip electrode portion 82, and the first chip electrode portion 81 and the second chip electrode portion 82 are aligned in the second direction D2. Therefore, according to this embodiment, the electronic component 100 can be made lower in height compared to a configuration in which the first chip electrode portion 81 and the second chip electrode portion 82 are aligned in the vertical direction (Z-axis direction).
[0063] Furthermore, according to this embodiment, the resistive layer 20 further has a third portion 23 located on the first direction D1 side relative to the second portion 22 and connected to the second portion 22. The electronic component 100 further includes a second substrate electrode portion 40 formed on the third portion 23 of the resistive layer 20. Therefore, according to this embodiment, the second substrate electrode portion 40 can function as an electrode for wire bonding with other electronic circuit boards.
[0064] Furthermore, according to another embodiment, the edge side surface 721 of the second coating portion 72 (the surface on the edge portion 311 side) is inclined to move away from the resistance layer 20 as it moves from the first coating portion 71 toward the second direction D2. As a result, the edge portion 311 of the first substrate electrode portion 30 is formed to penetrate deeply into the protective film 70 (second coating portion 72). Therefore, the area of the portion of the first substrate electrode portion 30 covered by the protective film 70 increases, making it more difficult for the first substrate electrode portion 30 to peel off from the resistance layer 20.
[0065] This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its essence. Furthermore, the components disclosed in the embodiments can be modified as appropriate. For example, some components from the total components shown in one embodiment may be added to the components of another embodiment, or some components from the total components shown in one embodiment may be removed from the embodiment.
[0066] Furthermore, the drawings schematically show each component in order to facilitate understanding, and the thickness, length, number, spacing, etc. of each component shown may differ from the actual dimensions due to the constraints of drawing creation. Also, the configuration of each component shown in the above embodiments is merely an example and is not particularly limiting, and it goes without saying that various modifications are possible within the scope that does not substantially deviate from the effects of this disclosure.
[0067] For example, in the embodiment described with reference to Figures 1 to 5, the first substrate electrode portion 30 had a wall portion 32, but the wall portion 32 may be omitted.
[0068] Furthermore, in the embodiment described with reference to Figures 1 to 5, the length L1 from the first base end 32a to the tip end 32b of the solder side surface 321 of the wall portion 32 is longer than the length L2 of the wall portion 32 in the first direction D1. However, the length L1 from the first base end 32a to the tip end 32b of the solder side surface 321 of the wall portion 32 may be less than or equal to the length L2 of the wall portion 32 in the first direction D1.
[0069] Furthermore, in the embodiment described with reference to Figures 1 to 5, the height h1 of the second coating portion 72 from the resistance layer 20 is higher than the height h2 of the wall portion 32 from the resistance layer 20. However, the height h1 of the second coating portion 72 from the resistance layer 20 may be less than or equal to the height h2 of the wall portion 32 from the resistance layer 20.
[0070] Furthermore, in the embodiment described with reference to Figures 1 to 5, the protective film 70 has a third covering portion 73, but the third covering portion 73 may be omitted.
[0071] Furthermore, in the embodiment described with reference to Figures 1 to 5, the protective film 70 has a fourth covering portion 74, but the fourth covering portion 74 may be omitted.
[0072] Furthermore, in the embodiment described with reference to Figures 1 to 5, the center line CL1 of the chip component 80 is located on the other side (+Y side) of the width direction WD relative to the center line CL2 of the first substrate electrode portion 30. However, the center line CL1 of the chip component 80 does not necessarily have to be located on the other side (+Y side) of the width direction WD relative to the center line CL2 of the first substrate electrode portion 30.
[0073] Furthermore, in the embodiment described with reference to Figures 1 to 5, the first chip electrode portion 81 and the second chip electrode portion 82 are aligned in the second direction D2 (Y-axis direction), but the first chip electrode portion 81 and the second chip electrode portion 82 may be aligned in the vertical direction (Z-axis direction).
[0074] Furthermore, in the embodiment described with reference to Figures 1 to 5, the electronic component 100 includes a second substrate electrode portion 40, but the second substrate electrode portion 40 may be omitted.
[0075] Furthermore, in the embodiment described with reference to Figures 1 to 5, the protective film 70 had two third covering portions 73, but the number of third covering portions 73 may be one. In other words, only one of the two ends of the protective film 70 in the Y-axis direction may cover the main surface 11 of the base material 10.
[0076] Furthermore, in the embodiment described with reference to Figure 5, the edge side surface 721 was an inclined surface, but the edge side surface 721 is not limited to an inclined surface. The edge side surface 721 only needs to be inclined so as to move away from the resistive layer 20 as it moves from the first covering portion 71 toward the second direction D2 side (-X side), and may be a curved surface, for example.
[0077] Figure 6 is a photograph of a cross-section of an electronic component 100 according to an embodiment. In this embodiment, the resistive layer 20 was a thin-film resistor. The material of the resistive layer 20 was tantalum nitride. The first substrate electrode portion 30 had a lower layer and an upper layer formed by plating on the upper surface of the lower layer, the lower layer being a NiCr-Pd vapor-deposited film and the upper layer being a NiPdAu plated film. The protective film 70 was solder resist. More specifically, the protective film 70 was a polyimide film. The chip component 80 was a multilayer ceramic capacitor.
[0078] As shown in Figure 6, in this embodiment, the second portion 22 of the resistive layer 20 and the edge 311 of the first substrate electrode portion 30 are covered with a protective film 70. Furthermore, the chip component 80 is fixed to the first substrate electrode portion 30 on the second direction D2 side of the second covering portion 72 using the first solder 91, thereby electrically connecting the first chip electrode portion 81 and the first substrate electrode portion 30. As a result, a structure is created in which problems such as oxidation of the second portion 22 of the resistive layer 20 are less likely to occur. Moreover, since the second covering portion 72 covers the edge 311 of the first substrate electrode portion 30, the structure is made in which the first substrate electrode portion 30 is less likely to peel off from the resistive layer 20.
[0079] Furthermore, in this embodiment, a wall portion 32 was formed that protrudes from the electrode body 31 and is interposed between the second coating portion 72 and the first solder 91. As a result, it was possible to prevent solder from flowing into the gap between the protective film 70 and the resistive layer 20.
[0080] Furthermore, in this embodiment, the solder side surface 321 (the surface on the first solder 91 side) of the wall portion 32 was curved. The length from the base end to the tip of the solder side surface 321 was longer than the length of the wall portion 32 in the first direction D1. As a result, the chip component 80 could be firmly bonded to the first substrate electrode portion 30.
[0081] Furthermore, in this embodiment, the height of the second coating portion 72 from the resistance layer 20 was made greater than the height of the wall portion 32 from the resistance layer 20. As a result, it was possible to prevent the first solder 91 from overflowing onto the upper surface of the protective film 70 or from overflowing the protective film 70 and extending to the outside of the protective film 70.
[0082] Furthermore, in this embodiment, the edge side surface 721 (the side facing the edge 311) of the second coating portion 72 was inclined so that it moved away from the resistive layer 20 as it moved from the first coating portion 71 toward the second direction D2. As a result, the first substrate electrode portion 30 became less likely to peel off from the resistive layer 20.
[0083] This disclosure provides electronic components that have industrial applicability.
[0084] 10 Substrate 20 Resistive layer 21 First part 22 Second part 23 Third part 30 First substrate electrode part 31 Electrode body 32 Wall part 32a First base end 32b Tip 33 Exposed part 40 Second substrate electrode part 41 Electrode body 70 Protective film 71 First coating part 72 Second coating part 73 Third coating part 74 Fourth coating part 75 Fifth coating part 80 Chip component 81 First chip electrode part 82 Second chip electrode part 91 First solder 100 Electronic component 311 Edge part 321 First surface (solder side) 411 Edge part 721 Edge side CL1 Center line CL2 Center line D1 First direction D2 Second direction h1 Height of second coating part from the resistive layer h2 Height of wall part from the resistive layer L1 L2: Length from the first base end to the tip of the solder side; WD: Length in the X-axis direction of the wall; WDL1: Width direction length of the first substrate electrode; WDL2: Width direction length of the chip component.
Claims
1. An electronic component comprising: a substrate; a resistive layer formed on the substrate, having a first portion and a second portion located on the first direction side with respect to the first portion and connected to the first portion; a substrate electrode portion formed on the first portion and having an edge portion on the first direction side; a protective film having a first covering portion covering the second portion and a second covering portion located on the second direction side opposite to the first direction side with respect to the first covering portion and connected to the first covering portion, wherein the second covering portion covers the edge portion; a chip component having a chip electrode portion; and solder for fixing the chip component to the substrate electrode portion on the second direction side of the second covering portion and electrically connecting the chip electrode portion and the substrate electrode portion.
2. The base electrode portion comprises an electrode body extending along the first portion and a wall portion protruding from the electrode body, wherein the wall portion is interposed between the second coating portion and the solder, as described in claim 1.
3. The electronic component according to claim 2, wherein the length from the base end to the tip of the solder-side surface of the wall portion is longer than the length of the wall portion in the first direction, and the base end indicates the location where the solder-side surface of the wall portion and the electrode body are connected.
4. The electronic component according to claim 2 or 3, wherein the height of the second coating portion from the resistive layer is greater than the height of the wall portion from the resistive layer.
5. The electronic component according to any one of claims 1 to 4, wherein the surface of the second covering portion on the edge side is inclined to move away from the resistive layer as it moves from the first covering portion toward the second direction.
6. The electronic component according to any one of claims 1 to 5, wherein the protective film further comprises a third covering portion that covers the substrate.
7. The electronic component according to any one of claims 1 to 6, wherein the length of the substrate electrode portion in the width direction perpendicular to the first direction is longer than the length of the chip component in the width direction, the substrate electrode portion has an exposed portion on one side in the width direction that does not overlap with the chip component, and the protective film further has a fourth covering portion that extends from the second covering portion in the second direction and covers a part of the exposed portion.
8. The electronic component according to claim 7, wherein the center line of the chip component extending in the first direction is located on the other side in the width direction with respect to the center line of the substrate electrode portion extending in the first direction.
9. The electronic component according to any one of claims 1 to 8, wherein the chip electrode portion is a first chip electrode portion, the chip component further has a second chip electrode portion, and the first chip electrode portion and the second chip electrode portion are aligned in the second direction.
10. The electronic component according to any one of claims 1 to 9, wherein the resistive layer further has a third portion located on the first direction side with respect to the second portion and connected to the second portion, the substrate electrode portion is a first substrate electrode portion, and the electronic component further comprises a second substrate electrode portion formed on the third portion.