capacitor

Abstract

This capacitor (10) comprises: a conductive substrate (20); a dielectric (31) disposed on the upper surface (201) of the substrate (20); an electrode (41) which is disposed on the upper surface of the dielectric (31) and faces the substrate (20) with the dielectric (31) therebetween; a terminal electrode which is for external connection and is disposed on an upper surface of the electrode (41) to be electrically connected to the electrode (41); and an insulating film (60) which covers the electrode (41), the dielectric (31), portions of the terminal electrode other than an external connection section of the terminal electrode, and a portion of the substrate (20). When Td is the thickness of the dielectric (31), and Tsr is a distance along the surface of the insulating film (60) which connects a portion of the terminal electrode which is not covered by the insulating film (60) and a portion of the substrate (20) which is not covered by the insulating film (60), the thickness Td and the distance Tsr satisfy the relationship Tsr < 18 x Td2.

Description

[Technical Field]

[0001] The present invention relates to capacitors formed using thin film technology. [Background technology]

[0002] Patent Document 1 describes a composite electronic component that includes a capacitor and an ESD protection element.

[0003] In Patent Document 1, the ESD protection element includes a pair of discharge electrodes facing each other with a gap therebetween and an electrostatic absorption layer disposed between the pair of discharge electrodes. The electrostatic absorption layer is a composite with a sea-island structure in which islands of conductive inorganic material are planarly and discontinuously dispersed in a dielectric layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-23247 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the composite electronic component of Patent Document 1, the discharge mechanism is formed inside the component, which results in a complex shape.

[0006] Therefore, an object of the present invention is to provide a capacitor having an ESD protection function with a simple configuration. [Means for solving the problem]

[0007] The capacitor of this invention comprises a lower electrode, a dielectric arranged on the upper surface of the lower electrode, an upper electrode arranged on the upper surface of the dielectric and facing the lower electrode across the dielectric, a terminal electrode for external connection arranged on the upper surface of the upper electrode and electrically connected to the upper electrode, and an insulating film covering the upper electrode, the dielectric, portions of the terminal electrode excluding the external connection portion, and part of the lower electrode.

[0008] The thickness of the dielectric is Td, and the distance along the surface of the insulating film connecting the part of the terminal electrode not covered by the insulating film and the part of the bottom electrode not covered by the insulating film is Tsr. The thickness Td and the distance Tsr are Tsr<18×Td. 2 Satisfy the relationship.

[0009] In this configuration, when static electricity is applied to the terminal electrode, the charge flows from the terminal electrode along the outer surface of the insulating film to the lower electrode by aerial discharge, and is then released from the lower electrode to ground through another terminal electrode. This prevents static charge from being applied to the dielectric between the upper and lower electrodes, thereby preventing dielectric breakdown. In this way, with this configuration, dielectric breakdown of the dielectric is prevented without the need for a separate functional element for discharge. [Effects of the Invention]

[0010] According to the present invention, a capacitor having an ESD protection function can be realized with a simple configuration. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1A is a top view of a capacitor according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AB shown in FIG. 1A. [Figure 2] FIG. 2 is an enlarged cross-sectional view of the vicinity of the side surface of the capacitor and the vicinity of the side surface of the terminal electrode according to the first embodiment of the present invention. [Figure 3] FIG. 3 is a side cross-sectional view showing a state in which static electricity is discharged from the capacitor according to the first embodiment. [Figure 4] FIG. 4 is a graph showing the relationship between the dielectric breakdown of the dielectric that constitutes the capacitance and the thickness Td and the shortest distance Tsr. [Figure 5] 5(A), 5(B), 5(C), 5(D), and 5(E) are cross-sectional views showing the configuration of the capacitor according to the first embodiment of the present invention in each manufacturing process. [Figure 6]6A, 6B, 6C, and 6D are cross-sectional views showing the structure of the capacitor according to the first embodiment of the present invention in each manufacturing process. [Figure 7] FIG. 7A is a top view of a capacitor according to a second embodiment of the present invention, and FIG. 7B is a cross-sectional view taken along line AB shown in FIG. 7A. [Figure 8] FIG. 8 is an enlarged cross-sectional view of the vicinity of a side surface of a capacitor and the vicinity of a side surface of a terminal electrode according to a second embodiment of the present invention. [Figure 9] FIG. 9 is an enlarged cross-sectional view of the vicinity of a side surface of a capacitor and the vicinity of a side surface of a terminal electrode according to a third embodiment of the present invention. [Figure 10] FIG. 10A is a top view of a capacitor according to a fourth embodiment of the present invention, and FIG. 10B is a cross-sectional view taken along line AB shown in FIG. 10A. [Figure 11] FIG. 11 is a cross-sectional view of a capacitor according to a fifth embodiment of the present invention. [Figure 12] FIG. 12 is a cross-sectional view of a capacitor according to a sixth embodiment of the present invention. [Figure 13] FIG. 13 is a cross-sectional view of a capacitor according to a seventh embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] [First embodiment] A capacitor according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1(A) is a top view of a capacitor according to the first embodiment of the present invention, and FIG. 1(B) is a view showing the AB cross section shown in FIG. 1(A). FIG. 2 is an enlarged cross-sectional view of the vicinity of the side surface of the capacitor according to the first embodiment of the present invention and the vicinity of the side surface of the terminal electrode. Note that in the drawings showing the configuration of each embodiment of the present invention, including FIG. 1(A), FIG. 1(B), and FIG. 2, dimensions are exaggerated to make the technology and configuration easier to understand. In particular, dimensions in the z-axis direction are exaggerated.

[0013] (Configuration of capacitor 10) As shown in Figures 1(A), 1(B), and 2, the capacitor 10 includes a substrate 20, a dielectric 31, a dielectric 32, an electrode 41, an electrode 42, a protective film 50, an insulating film 60, a base electrode 71 for a terminal electrode, a base electrode 72 for a terminal electrode, an external connection electrode 81, and an external connection electrode 82.

[0014] The substrate 20 is a flat plate having an upper surface 201 and a lower surface 202. The thickness of the substrate 20 is, for example, about 150 μm. The substrate 20 is a conductive semiconductor, for example, made of Si. The resistivity of the substrate 20 is, for example, 10 mΩ·cm, and may be about 1 Ω·cm. The substrate 20 corresponds to an example of a "lower electrode" of the present invention.

[0015] The dielectric 31 and the dielectric 32 are disposed on the upper surface 201 of the substrate 20. The dielectric 31 and the dielectric 32 are, for example, flat films and rectangular in top view (viewed in a direction parallel to the z-axis direction). The dielectric 31 and the dielectric 32 are disposed apart from each other on the upper surface 201. For example, as shown in FIG. 1(B), the dielectric 31 and the dielectric 32 are disposed apart from each other in the x-axis direction of the substrate 20.

[0016] The thickness of the dielectric 31 and the dielectric 32 is, for example, 1.0 μm. The dielectric 31 and the dielectric 32 are made of, for example, SiO2. The thickness and material of the dielectric 31 and the thickness and material of the dielectric 32 do not need to be the same, but if they are the same, manufacturing becomes easier and the heights of the external connection electrodes 81 and 82 become aligned, making mounting easier.

[0017] The electrode 41 is disposed on the upper surface of the dielectric 31. More specifically, the electrode 41 is disposed on the surface of the dielectric 31 opposite to the surface with which the substrate 20 abuts. In other words, the electrode 41 and the substrate 20 are disposed with the dielectric 31 sandwiched between them.

[0018] In this way, the structure in which the electrode 41 and the conductive substrate 20 sandwich the dielectric 31 creates a capacitance, and this capacitance is determined by the opposing area between the electrode 41 and the substrate 20, the dielectric constant of the dielectric 31, and the thickness of the dielectric 31.

[0019] The electrode 41 has a thickness of, for example, 1.0 μm and is made of, for example, Al.

[0020] The electrode 42 covers the dielectric 32 together with the substrate 20. Specifically, the electrodes 42 are disposed on the top surface and each side surface of the dielectric 32, and are electrically and physically connected to the substrate 20. The electrode 42 is not directly physically connected to the electrode 41. The thickness of the electrode 42 is, for example, 1.0 μm. The electrode 42 is made of, for example, Al.

[0021] The protective film 50 is disposed on the upper surface side of the substrate 20. The protective film 50 covers the upper surface 201 of the substrate 20, the dielectric 31, the electrode 41, and the electrode 42. In this case, the protective film 50 has a recess 501 that exposes a part of the upper surface of the electrode 41, and a recess 502 that exposes a part of the upper surface of the electrode 42.

[0022] The protective film 50 has a thickness of, for example, 0.8 μm. The protective film 50 is made of, for example, SiN. The protective film 50 is a so-called passivation layer.

[0023] Insulating film 60 covers upper surface 201 of substrate 20 and protective film 50. Insulating film 60 has a recess 691 near the bottom of which is contained within recess 501 of protective film 50 and exposes the upper surface of electrode 41, and a recess 692 near the bottom of which is contained within recess 502 of protective film 50 and exposes the upper surface of electrode 42. In other words, insulating film 60 covers electrode 41, electrode 42, dielectric 31, dielectric 32, and portions excluding external connection portions of terminal electrodes described later, as well as a portion (upper surface 201) of substrate 20.

[0024] The insulating film 60 has a thickness of, for example, 5.0 μm. The insulating film 60 is, for example, an organic film made of a predetermined material and having insulating properties. The insulating film 60 is a so-called solder resist layer.

[0025] Base electrode 71 for the terminal electrode is disposed on upper surface 601 of insulating film 60, the inner surface of recess 691, and the surface of electrode 41 exposed by recess 691. Base electrode 71 is rectangular in top view. Base electrode 71 is an electrode layer formed by sputtering Ti and Cu, for example, with a thickness of 0.1 μm and a thickness of 1.0 μm.

[0026] The external connection electrode 81 covers the upper surface of the base electrode 71. The external connection electrode 81 is, for example, a plated layer in which Ni and Au are formed in this order, with the Ni having a thickness of 3.0 μm and the Au having a thickness of 0.1 μm.

[0027] The base electrode 71 and the external connection electrode 81 constitute a "terminal electrode" (terminal electrode for the upper electrode) of the present invention.

[0028] Base electrode 72 for the terminal electrode is disposed on upper surface 601 of insulating film 60, the inner surface of recess 692, and the surface of electrode 42 exposed by recess 692. Base electrode 72 is rectangular in top view. Base electrode 72 is an electrode layer formed by sputtering, for example, Ti and Cu in that order, with the Ti having a thickness of 0.1 μm and the Cu having a thickness of 1.0 μm.

[0029] The external connection electrode 82 covers the upper surface of the base electrode 72. The external connection electrode 82 is, for example, a plated layer in which Ni and Au are formed in this order, with the Ni having a thickness of 3.0 μm and the Au having a thickness of 0.1 μm.

[0030] The base electrode 72 and the external connection electrode 82 constitute terminal electrodes, more specifically, "terminal electrodes for lower electrodes" of the present invention. The base electrodes 71 and 72 and the terminal electrodes 81 and 82 are shown schematically as rectangles. However, the corners may be rounded, or the corners may be chamfered so that the corresponding corners are formed at angles greater than 90 degrees.

[0031] With the above configuration, the capacitor 10 is realized as a capacitor formed by thin film technology (MIM capacitor).

[0032] (Specific Description of Discharge Function of Capacitor 10) As shown in FIG. 2, in the capacitor 10, the side surface 711 of the base electrode 71 for the terminal electrode is in contact with the upper surface 601 of the insulating film 60 and is disposed in the vicinity of the side surface 611 of the insulating film 60.

[0033] The distance between the side surface 711 and the side surface 611 of the insulating film 60 is defined as D761. More specifically, the distance D761 is the shortest distance along the upper surface 601 of the insulating film 60 between the side surface 711 and the side surface 611.

[0034] The thickness of the insulator is defined as T611. More specifically, the thickness T611 is the shortest distance from the point where the straight line constituting the distance D761 touches the side surface 611 to the side surface of the substrate 20 in the thickness direction (z-axis direction) of the insulating film 60.

[0035] Therefore, the distance obtained by adding the distance D761 and the thickness T611 is the shortest distance along the outer surface of the insulating film 60 between the terminal electrode and the substrate 20. This shortest distance is defined as Tsr (Tsr=D761+T611).

[0036] The thickness of the dielectric 31 is Td.

[0037] The shortest distance Tsr and the thickness Td satisfy the following relationship.

[0038] Tsr<18×Td 2 -(Formula 1) By satisfying this relationship, the following effects are achieved.

[0039] As an example, a combination of a dielectric thickness Td of approximately 1.0 μm, a distance D761 of approximately 8 μm, and a thickness T611 of approximately 8 μm is conceivable.

[0040] FIG. 3 is a side cross-sectional view showing a state in which static electricity is discharged from the capacitor according to the first embodiment.

[0041] As shown in FIG. 3, static electricity (ESD) is applied to the terminal electrodes (external connection electrode 81 and base electrode 71) from the outside.

[0042] Here, when the relationship of formula 1 is satisfied, the voltage generated by the static charge is discharged in the air through a path (air path) passing through the surface of the insulating film 60 before it reaches the breakdown voltage of the dielectric 31, and the static charge flows to the substrate 20.

[0043] The substrate 20 is electrically connected to the terminal electrodes for the lower electrode (external connection electrode 82 and base electrode 72) that are connected to an external ground potential through the electrode 42. Therefore, the charge that has flowed into the substrate 20 is released to the ground through the electrode 42 and the terminal electrode for the lower electrode.

[0044] This prevents static electricity from being applied to the dielectric 31 between the electrode 41 and the substrate 20. Therefore, dielectric breakdown of the dielectric 31 is prevented.

[0045] Figure 4 is a graph showing the relationship between the dielectric breakdown of the dielectric that constitutes the capacitance and the thickness Td and the shortest distance Tsr. In Figure 4, the solid line shows the curve (function) obtained by replacing the inequality sign in (Equation 1) with an equal sign. Figure 4 also shows the state of dielectric breakdown of the dielectric when 1 kV HBM static electricity is applied to the terminal electrode, with OK meaning no breakdown and NG meaning breakdown.

[0046] As shown in FIG. 4, if (Equation 1) is satisfied, no dielectric breakdown occurs in the dielectric, and if (Equation 1) is not satisfied, dielectric breakdown occurs.

[0047] Although 1 kV is used as an example here, similar trends were observed at 2 kV and 5 kV.

[0048] In this way, by satisfying the relationship of (Equation 1), the capacitor 10 can suppress the dielectric breakdown of the dielectric 31.

[0049] Unlike the prior art, capacitor 10 does not require a separate functional element for discharge. This allows capacitor 10 to suppress dielectric breakdown of dielectric 31 with a simple configuration. Furthermore, capacitor 10 can be made thinner and more compact than capacitors configured with a separate functional element for discharge, as in the prior art.

[0050] (One Example of a Manufacturing Method for Capacitor 10) Figures 5(A), 5(B), 5(C), 5(D), 5(E), 6(A), 6(B), 6(C), and 6(D) are cross-sectional views showing the configuration of the capacitor according to the first embodiment of the present invention at each manufacturing step. In the following description of the manufacturing method, illumination of the parts specifically shown in the description of the configuration above will be omitted, and only those points that require additional explanation will be explained.

[0051] A substrate 20 is loaded, and as shown in Fig. 5(A), a dielectric 30 is formed on an upper surface 201 of the substrate 20. For example, SiO2 may be formed as a thermal oxide film on a Si substrate, or an SiO2 or SiN film may be formed by CVD (Chemical Vapor Deposition).

[0052] The dielectric 30 is pattern-etched to form the dielectrics 31 and 32 as shown in FIG. 5(B).

[0053] 5(C), an electrode 40 is formed on the upper surface 201 side of the substrate 20 so as to cover the dielectric 31 and the dielectric 32. A metal such as Al or Cu may be formed by using a vapor deposition method, a sputtering method, plating, or the like.

[0054] The electrode 40 is pattern-etched to form electrodes 41 and 42 as shown in FIG. 5(D).

[0055] 5(E), a protective film 50 (passivation film) is formed on the upper surface 201 of the substrate 20 so as to cover the dielectric 31, the electrode 41, and the electrode 42. The protective film may be formed of SiO2, SiN, or the like by using CVD or spin coating.

[0056] The protective film 50 is pattern-etched to form a recess 501 exposing a portion of the upper surface of the electrode 41 and a recess 502 exposing a portion of the upper surface of the electrode 42, as shown in FIG. 6(A).

[0057] 6(B), an insulating film 60 is formed so as to cover the protective film 50. At this time, the insulating film 60 has a recess 691 and a recess 692.

[0058] 6(C), the power supply film 70 is formed so as to cover the upper surface 601 of the insulating film 60, the wall surfaces of the recess 691, and the wall surfaces of the recess 692. The power supply film 70 is formed by, for example, sputtering or electroless plating.

[0059] 6(D), the external connection electrodes 81 and 82 are formed so as to include the regions of the recesses 691 and 692 in the power supply film 70. The external connection electrodes 81 and 82 are realized by, for example, electrolytic plating using a mask.

[0060] Thereafter, the power supply film 70 is pattern-etched to form the base electrodes 71 and 72 .

[0061] The processes up to this point are performed on a motherboard having a plurality of capacitors 10 arranged thereon. After this, the substrate 20 is appropriately ground from the lower surface 202 side, and the motherboard is cut into a plurality of individual capacitors 10.

[0062] [Second embodiment] A capacitor according to a second embodiment of the present invention will be described with reference to the drawings. Fig. 7(A) is a top view of the capacitor according to the second embodiment of the present invention, and Fig. 7(B) is a cross-sectional view taken along line AB of Fig. 7(A). Fig. 8 is an enlarged cross-sectional view of the vicinity of the side surface of the capacitor according to the second embodiment of the present invention and the vicinity of the side surface of the terminal electrode.

[0063] 7(A), 7(B), and 8, the capacitor 10A according to the second embodiment differs from the capacitor 10 according to the first embodiment in the configuration of the terminal electrodes (base electrode 71A, external connection electrode 81A). The other configuration of the capacitor 10A is the same as that of the capacitor 10, and a description of the similar parts will be omitted.

[0064] The base electrode 71A is rectangular in top view and has a side surface 711, a side surface 712, a side surface 713, and a side surface 714. The side surface 711 is close to and parallel to the side surface 611 of the insulating film 60. The side surface 712 faces the side surface 711 and is the side surface of the base electrode 71A on the base electrode 72 side. The side surface 713 is close to and parallel to the side surface 613 of the insulating film 60. The side surface 714 faces the side surface 713 and is close to and parallel to the side surface 614 of the insulating film 60. Note that the term "parallel" here does not necessarily mean perfectly parallel, but may include a range of manufacturing error.

[0065] Base electrode 71A includes a main portion, protruding portion 791, protruding portion 793, and protruding portion 794. The main portion of base electrode 71A is the rectangular portion as seen from above.

[0066] When the base electrode 71A is viewed from above, the protruding portion 791 protrudes from the side surface 711 of the main portion toward the side surface 611 of the insulating film 60. In this case, the width of the protruding portion 791 is smaller than the width of the side surface 711.

[0067] When the base electrode 71A is viewed from above, the protruding portion 793 protrudes from the side surface 713 of the main portion toward the side surface 613 of the insulating film 60. In this case, the width of the protruding portion 793 is smaller than the width of the side surface 713.

[0068] When the base electrode 71A is viewed from above, the protruding portion 794 protrudes from the side surface 714 of the main portion toward the side surface 614 of the insulating film 60. In this case, the width of the protruding portion 794 is smaller than the width of the side surface 714.

[0069] In such a configuration, the shortest distance Tsr is the shortest of the shortest distance along the outer surface (top surface 601 and side surface 611) of the insulating film 60 from the tip 7911 of the protrusion 791 to the side surface of the substrate 20, the shortest distance along the outer surface (top surface 601 and side surface 613) of the insulating film 60 from the tip 7931 of the protrusion 793 to the side surface of the substrate 20, and the shortest distance along the outer surface (top surface 601 and side surface 614) of the insulating film 60 from the tip 7941 of the protrusion 794 to the side surface of the substrate 20.

[0070] 8, for example, the distance between the tip 7911 of the protrusion 791 and the side surface 611 of the insulating film 60 is D761A, and the shortest distance Tsr is the sum of this distance D761A and the thickness T611. As an example, a possible combination is that the thickness Td of the dielectric is approximately 1.0 μm, the distance D761A is approximately 3 μm, and the thickness T611 is approximately 8 μm.

[0071] With this configuration, capacitor 10A, like capacitor 10, can discharge static electricity through aerial discharge and prevent dielectric breakdown of dielectric 31.

[0072] Furthermore, capacitor 10A can control the position of air discharge from the terminal electrode. Also, capacitor 10A can shorten the shortest distance Tsr without changing the position of side surface 711 of the terminal electrode on the side surface 611 side of insulating film 60. As a result, capacitor 10A can make the terminal electrode smaller while maintaining discharge performance, and can reduce the parasitic capacitance formed by the terminal electrode and substrate 20.

[0073] Furthermore, in capacitor 10A, tip 7911 of protrusion 791, tip 7931 of protrusion 793, and tip 7941 of protrusion 794 are tapered. This allows capacitor 10A to further control the discharge location.

[0074] In addition, capacitor 10A has been shown to have three protrusions (protrusion 791, protrusion 793, and protrusion 794). However, the number of protrusions is not limited to this and may be at least one. Also, for example, one side surface may have multiple protrusions.

[0075] Furthermore, when capacitor 10A has an even number of protrusions, such as two, it is preferable to provide a pair of protrusions on side surface 713 and side surface 714. This ensures that even if misalignment occurs when capacitor 10A is cut from the motherboard into individual pieces, either the protrusion on side surface 713 or the protrusion on side surface 714 will be positioned so as to always satisfy the above-mentioned (Equation 1). This allows capacitor 10A to more reliably suppress dielectric breakdown of dielectric 31.

[0076] [Third embodiment] A capacitor according to a third embodiment of the present invention will be described with reference to the drawings. Fig. 9 is an enlarged cross-sectional view of the vicinity of the side surface of the capacitor according to the third embodiment of the present invention and the vicinity of the side surface of the terminal electrode.

[0077] 9, the capacitor 10B according to the third embodiment differs from the capacitor 10A according to the second embodiment in the configuration of the terminal electrodes (base electrode 71B, external connection electrode 81B). The other configuration of the capacitor 10B is the same as that of the capacitor 10A, and a description of the similar parts will be omitted.

[0078] The external connection electrode 81B has an outer shape larger than that of the base electrode 71B. For example, a side surface 891B of the external connection electrode 81B on the side surface 611 side of the insulating film 60 protrudes further toward the side surface 611 than a side surface 711 of the base electrode 71B on the side surface 611 side of the insulating film 60.

[0079] In the portion of the external connection electrode 81B that protrudes beyond the base electrode 71B, a gap GAP is formed between the external connection electrode 81B and the insulating film 60. The gap GAP is, for example, approximately 0.1 μm to 2.0 μm. Such a gap GAP can be realized by selective etching in which the base electrode 71B is more easily etched than the external connection electrode 81B.

[0080] In such a configuration, a distance D861B between a side surface 891B of the external connection electrode 81B (for example, the tip of the protrusion of the external connection electrode 81B corresponding to the protrusion 791) and a side surface 611 of the insulating film 60 can be made shorter than the distance between a side surface 711B of the base electrode 71B (for example, the tip of the protrusion 791) and a side surface 611 of the insulating film 60. In this case, the shortest distance Tsr is the sum of the distance D861B and the thickness T611.

[0081] With this configuration, capacitor 10B exhibits the same effects as capacitor 10B.

[0082] Furthermore, in capacitor 10B, the area of ​​base electrode 71B that is disposed on upper surface 601 of insulating film 60 can be reduced. This allows capacitor 10B to suppress the parasitic capacitance that occurs between electrode 41 and base electrode 71B. In particular, as shown in FIG. 9, side surface 711B of base electrode 71B is farther from side surface 611 of insulating film 60 than the side surface of electrode 41 that is closer to side surface 611 of insulating film 60 (see dashed line in FIG. 9), which allows the opposing area between electrode 41 and base electrode 71B to be further reduced. Therefore, capacitor 10B can further suppress the parasitic capacitance that occurs between electrode 41 and base electrode 71B.

[0083] Even with this structure, the external connection electrode 81B can prevent the shortest distance Tsr from becoming too long, thereby achieving aerial discharge at a desired voltage. Furthermore, in the region where the external connection electrode 81B and the electrode 41 face each other without the base electrode 71B in between, a gap GAP is present, so that the capacitor 10B can prevent parasitic capacitance from occurring between the electrode 41 and the external connection electrode 81B.

[0084] [Fourth embodiment] A capacitor according to a fourth embodiment of the present invention will be described with reference to the drawings. Fig. 10(A) is a top view of the capacitor according to the fourth embodiment of the present invention, and Fig. 10(B) is a cross-sectional view taken along line AB of Fig. 10(A).

[0085] 10(A) and 10(B), the capacitor 10C according to the fourth embodiment differs from the capacitor 10A according to the second embodiment in that it includes an insulating film 90. Other configurations of the capacitor 10C are similar to those of the capacitor 10A, and a description of similar parts will be omitted.

[0086] The insulating film 90 of the capacitor 10C covers the insulating film 60, the base electrode 71C (with a configuration similar to that of the base electrode 71A), the base electrode 72, the external connection electrode 81C (with a configuration similar to that of the external connection electrode 81A), and the external connection electrode 82. In this case, the insulating film 90 exposes to the outside the central portion (portion used as a mounting electrode) of the external connection electrode 81C in top view, the central portion (portion used as a mounting electrode) of the external connection electrode 82 in top view, a portion including a tip 7911 of the protruding portion 791 of the base electrode 71C, a portion including a tip 7931 of the protruding portion 793 of the base electrode 71C, and a portion including a tip 7941 of the protruding portion 794 of the base electrode 71C.

[0087] The insulating film 90 may be made of the same material as the insulating film 60 or a different material, but using the same material is expected to improve adhesion between the insulating film 60 and the insulating film 90. If they are made of the same material, the boundary between the insulating film 60 and the insulating film 90 may be unclear.

[0088] With this configuration, capacitor 10C can absorb shocks during mounting. Furthermore, because the protruding portion of capacitor 10C is exposed from insulating film 90, it can suppress dielectric breakdown of dielectric 31 due to aerial discharge of static electricity, just like capacitor 10A. In other words, capacitor 10C has the same effects as capacitor 10A.

[0089] [Fifth embodiment] A capacitor according to a fifth embodiment of the present invention will be described with reference to the drawings. Fig. 11 is a cross-sectional view of the capacitor according to the fifth embodiment of the present invention. Fig. 11 shows the AB cross-section similar to Fig. 1(A) and the like.

[0090] 11, the capacitor 10D according to the fifth embodiment differs from the capacitor 10 according to the first embodiment in that it includes an electrode 41LP and an electrode 42D instead of the electrode 42. The other configuration of the capacitor 10D is the same as that of the capacitor 10, and a description of similar parts will be omitted.

[0091] The electrode 41LP is disposed between the substrate 20 and the dielectric 31. The electrode 41LP is connected to the substrate 20. The electrode 41LP faces the electrode 41 with the dielectric 31 interposed therebetween.

[0092] In this configuration, the electrode 41LP and the substrate 20 form the "lower electrode" of the present invention.

[0093] The electrode 42D is formed by combining an electrode film formed at the same time as the electrode 41LP with the electrode 42 of the capacitor 10, and covers the entire surface of the dielectric 32.

[0094] With this configuration, capacitor 10D exhibits the same effects as capacitor 10.

[0095] [Sixth embodiment] A capacitor according to a sixth embodiment of the present invention will be described with reference to the drawings. Fig. 12 is a cross-sectional view of the capacitor according to the sixth embodiment of the present invention. Fig. 12, like Fig. 11, shows the AB cross-section similar to Fig. 1(A) and the like.

[0096] 12, the capacitor 10E according to the sixth embodiment differs from the capacitor 10D according to the fifth embodiment in that it includes a lower protective film 50LP, a plurality of via conductors 419, and a plurality of via conductors 429. The other configuration of the capacitor 10E is the same as that of the capacitor 10D, and a description of similar parts will be omitted.

[0097] The capacitor 10E includes a lower protective film 50LP on the upper surface 201 of the substrate 20. The lower protective film 50LP is made of the same material as the protective film 50, for example.

[0098] The lower protective film 50LP is disposed between the substrate 20 and the electrode 41LP, and is disposed between the substrate 20 and the electrode 42E (which has the same configuration as the electrode 42D).

[0099] The plurality of via conductors 419 are formed in the lower protective film 50LP and penetrate the lower protective film 50LP in the thickness direction. The plurality of via conductors 419 connect the substrate 20 and the electrode 41LP for electrical continuity.

[0100] The plurality of via conductors 429 are formed in the lower protective film 50LP and penetrate the lower protective film 50LP in the thickness direction. The plurality of via conductors 429 connect the substrate 20 and the electrode 42E for electrical continuity.

[0101] With this configuration, capacitor 10E exhibits the same effects as capacitor 10D.

[0102] [Seventh embodiment] A capacitor according to a seventh embodiment of the present invention will be described with reference to the drawings. Fig. 13 is a cross-sectional view of the capacitor according to the seventh embodiment of the present invention. Fig. 13 shows the AB cross-section similar to Fig. 1(A) and the like.

[0103] 13, the capacitor 10F according to the seventh embodiment differs from the capacitor 10 according to the first embodiment in that it includes an electrode 20e and a substrate 20i instead of the substrate 20. The other configuration of the capacitor 10F is the same as that of the capacitor 10, and a description of similar parts will be omitted.

[0104] The substrate 20i is an insulating substrate and is made of, for example, alumina.

[0105] The electrode 20e is disposed on the upper surface 201 of the substrate 20i. The electrode 20e is electrically conductive. The lower electrode is thus realized by the electrode 20e disposed on the insulating substrate 20i.

[0106] The dielectric 31 and the dielectric 32 are disposed on the upper surface of the electrode 20e (the surface opposite to the surface in contact with the substrate 20i).

[0107] In capacitor 10F, T611 is not the distance from the substrate but the distance from electrode 20e.

[0108] With this configuration, the capacitor 10F exhibits the same effects as the capacitor 10.

[0109] For convenience, the shape of the insulating film 60 is shown as a rectangle when viewed from the Y-axis direction, but it does not necessarily have to be rectangular, and it may be a shape in which a straight line or a curved line connects the base electrode or the connection terminal electrode to the substrate. Regardless of the shape, it is sufficient that the shortest distance from the base electrode or the connection terminal electrode to the substrate on which each functional film is not formed, which passes through the surface of the insulating film 60, is defined as Tsr, and that Formula 1 is satisfied.

[0110] Although an example has been shown in which the side surface 611 of the insulating film 60 is integrated with the side surface of the substrate, the substrate 20 may protrude from the capacitor formation area when viewed from the Z-axis direction. In this case, the distance between a point on the upper surface 201 of the substrate 20 and the end of the base electrode or the connection terminal electrode is the shortest distance Tsr.

[0111] The configurations of the above-described embodiments can be combined as appropriate, and effects according to each combination can be achieved.

[0112] <1> A lower electrode; a dielectric disposed on an upper surface of the lower electrode; an upper electrode disposed on an upper surface of the dielectric and facing the lower electrode with the dielectric interposed therebetween; a terminal electrode for external connection disposed on an upper surface of the upper electrode and electrically connected to the upper electrode; an insulating film covering the upper electrode, the dielectric, a portion of the terminal electrode excluding an external connection portion, and a portion of the lower electrode; Equipped with The thickness of the dielectric is Td, a distance along the surface of the insulating film connecting a portion of the terminal electrode not covered with the insulating film and a portion of the lower electrode not covered with the insulating film is defined as Tsr; The Td and the Tsr are Tsr<18×Td 2 Satisfy the relationship of Capacitor.

[0113] <2> the terminal electrode has a protruding portion protruding from a side surface of a main portion having a predetermined shape in top view, The distance Tsr is a distance connecting the protrusion and the lower electrode. <1> The capacitor according to claim 1.

[0114] <3> The protrusion includes a plurality of protrusions arranged at positions facing each other with the main portion interposed therebetween. <2> The capacitor according to claim 1.

[0115] <4> The protrusion has a tapered tip. <2> or <3> The capacitor according to claim 1.

[0116] <5> The terminal electrode is a base electrode electrically connected to the upper electrode; an external connection electrode formed on the base electrode; Equipped with the base electrode and the external connection electrode have portions facing the upper electrode, the external connection electrode protrudes beyond the base electrode, a gap is formed between the external connection electrode and the upper electrode at a portion where the external connection electrode protrudes beyond the base electrode; <1> ~ <3> 10. The capacitor according to claim 9, wherein

[0117] <6> The lower electrode is a conductive semiconductor substrate. <1> ~ <5> 10. The capacitor according to claim 9, wherein

[0118] <7> the lower electrode comprises a conductive film disposed between a conductive semiconductor substrate and the dielectric; <6> The capacitor according to claim 1.

[0119] <8> The lower electrode is an insulating substrate; a conductive film disposed between the insulating substrate and the dielectric; Equipped with <1> ~ <5> 10. The capacitor according to claim 9, wherein

[0120] <9> the terminal electrode is electrically connected to the upper electrode; Further provided is a lower electrode terminal electrode electrically connected to the lower electrode. <1> ~ <8> 10. The capacitor according to claim 9, wherein

[0121] <10> The semiconductor substrate is Si and the dielectric is SiO2. <6> or <7> The capacitor according to claim 1. [Explanation of symbols]

[0122] 10, 10A, 10B, 10C, 10D, 10E, 10F: Capacitors 20, 20i: PCB 20e: Electrode 30, 31, 32: Dielectric 40, 41, 41LP, 42, 42D, 42E: Electrode 50:Protective film 50LP: Lower protective film 60: insulating film 70: Power supply membrane 71, 71A, 71B, 71C, 72: base electrodes 81, 81A, 81B, 81C, 82: external connection electrodes 90: insulating film 201:Top surface 202: Bottom surface 419, 429: Via conductor 501, 502: recessed portion 601:Top surface 611, 613, 614: Side 691, 692: recessed parts 711, 711B, 712, 713, 714: Side 791, 793, 794: Protrusion 891B: Side 7911, 7931, 7941: Tip

Claims

1. A lower electrode; a dielectric disposed on an upper surface of the lower electrode; an upper electrode disposed on an upper surface of the dielectric and facing the lower electrode with the dielectric interposed therebetween; a terminal electrode for external connection disposed on an upper surface of the upper electrode and electrically connected to the upper electrode; an insulating film covering the upper electrode, the dielectric, a portion of the terminal electrode excluding an external connection portion, and a portion of the lower electrode; Equipped with The thickness of the dielectric is Td, Tsr is the shortest distance along the surface of the insulating film connecting the portion of the terminal electrode that is not covered with the insulating film and the portion of the lower electrode that is not covered with the insulating film, The thickness Td and the distance Tsr are Tsr<18×Td ２ Fulfilling the relationship, the terminal electrode has a protruding portion protruding from a side surface of a main portion having a predetermined shape in top view, The distance Tsr is a distance connecting the protrusion and the lower electrode. Capacitor.

2. A lower electrode; a dielectric disposed on an upper surface of the lower electrode; an upper electrode disposed on an upper surface of the dielectric and facing the lower electrode with the dielectric interposed therebetween; a terminal electrode for external connection disposed on an upper surface of the upper electrode and electrically connected to the upper electrode; an insulating film covering the upper electrode, the dielectric, a portion of the terminal electrode excluding an external connection portion, and a portion of the lower electrode; Equipped with The thickness of the dielectric is Td, Tsr is the shortest distance along the surface of the insulating film connecting the portion of the terminal electrode that is not covered with the insulating film and the portion of the lower electrode that is not covered with the insulating film, The thickness Td and the distance Tsr are Tsr<18×Td2 Fulfilling the relationship, The terminal electrode is a base electrode electrically connected to the upper electrode; an external connection electrode formed on the base electrode; Equipped with the base electrode has a portion in contact with the dielectric on a surface opposite to a surface of the upper electrode that is in contact with the dielectric, the external connection electrode has a portion that contacts the base electrode on the side opposite to the surface that contacts the upper electrode, and protrudes beyond the base electrode; a gap is formed between the external connection electrode and the upper electrode at a portion where the external connection electrode protrudes beyond the base electrode; Capacitor.

3. the terminal electrode has a protruding portion protruding from a side surface of a main portion having a predetermined shape in top view, The distance Tsr is a distance connecting the protrusion and the lower electrode. The capacitor of claim 2 .

4. The protrusion is a plurality of protrusions arranged at positions facing each other across the main portion; The capacitor according to claim 1 or 3.

5. The protrusion has a tapered tip. The capacitor according to claim 1 or 3.

6. The lower electrode is a conductive semiconductor substrate. The capacitor according to claim 1 or 2.

7. the lower electrode comprises a conductive film disposed between a conductive semiconductor substrate and the dielectric; The capacitor of claim 6.

8. The lower electrode is an insulating substrate; a conductive film disposed between the insulating substrate and the dielectric; Equipped with The capacitor according to claim 1 or 2.

9. the terminal electrode is electrically connected to the upper electrode; Further provided is a lower electrode terminal electrode electrically connected to the lower electrode. The capacitor according to claim 1 or 2.

10. the semiconductor substrate is Si, The dielectric is SiO ２ That is, The capacitor of claim 6.

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