Improved device and process for forming membrane capacitor devices - Patents.com

Abstract

An improved capacitor and method of making the capacitor are described. The capacitor comprises an upper reinforcing encapsulant layer and a lower reinforcing encapsulant layer with a capacitive element between the upper and lower reinforcing encapsulant layers. The capacitive element comprises an anode, a dielectric on the anode, and a cathode on the dielectric. An inner reinforcing encapsulant layer is between the upper and lower reinforcing encapsulant layers.

Description

[Technical field]

[0001] The present invention relates to capacitors and methods of making electronic components, particularly capacitors, preferably valve metal capacitors, which improve volumetric efficiency while maintaining or improving electrical performance. More particularly, the present invention provides improved capacitors and methods of making the improved capacitors with improved volumetric efficiency achieved by using a film and resin system, e.g., a prepreg, that forms an encapsulant of controllable thickness between the capacitive element and the external capacitor surface. [Background technology]

[0002] In the manufacture of valve metal capacitors, particularly surface mount valve metal capacitors, it is standard practice to form a monolithic structure consisting of an anode lead extending from an anode. A dielectric and a charge collecting cathode are provided on the surface of the anode, and a dielectric is provided between the anode and cathode. The anode is typically roughened or has an increased surface area on which the dielectric and cathode are formed, thereby increasing the capacitance of the device. The manufacturing process includes forming the anode lead extending from the anode on a lead frame at a first location, and attaching the cathode to the lead frame at a second location.

[0003] The anode and cathode elements must be sufficiently separated to avoid electrical arcing, as will be readily appreciated. This requirement results in a loss of volumetric efficiency, since a significant volume of the final capacitor device does not contribute to capacitance. For example, referring to FIG. 1A, the volume of the capacitor surrounding the anode lead 3, which extends from the anode face to which it extends, to the outer edge of the encapsulant 8, has no electrical purpose and serves only the function of providing a location for attaching the lead frame 4 to the anode lead while being spaced far enough away from the cathode layer to avoid damage during welding. This challenge is further exacerbated by the need to provide sufficient separation between the active area of ​​the capacitive element and the weld 9. This is to ensure that the effects of the welding operation do not radiate unabated through the environment towards the sensitive and unprotected dielectric and cathode layers, degrading their quality and performance. Shielding the element from the welding process does not help reduce the volume it occupies, since practical limits of manufacturing precision do not allow it to be shorter than necessary without shielding. Combining multiple capacitive elements into a single capacitor further reduces volumetric efficiency.

[0004] Electronics manufacturers, the primary buyers of surface mount capacitors, have a large installed manufacturing infrastructure geared towards mounting surface mount capacitors on circuit boards or related elements to form electrical subassemblies. It is therefore necessary to provide capacitors that are structurally similar to currently employed surface mount capacitors. In particular, the size, shape, and dimensions of the device must match the installed base for use with existing mounting locations and mounting systems. The electronics industry is also constantly seeking to miniaturize electronic devices, or to extract more capacity and capability from the same size device. This forces component manufacturers, such as capacitors, to strive for more functionality in a given volume. These conflicting demands have led to a desire for surface mount capacitors that mimic industry standard surface mount capacitors in size and lead orientation, while also having higher volumetric efficiency, i.e., capacitance per unit volume. To address the reduced volumetric efficiency of mounting the anodes to their respective lead frames, some manufacturers have attempted to mount the anodes outside the encapsulant. Several methods of connecting the anode extensions to existing external terminals outside the encapsulant have been proposed in References 1 and 2, which are incorporated herein in their entireties. These methods involve embedding a portion of the conventional leadframe material, where the anode and cathode are bonded to the leadframe, or its equivalent, in an encapsulant and connecting the edge of the terminal to the exposed anode extension with a conductive layer applied to the edge of the device.

[0005] Other methods of manufacture are described in JP 2003-233663 A, incorporated herein in its entirety. Described therein is a device having an anode extension and a portion of an applied conductive cathode exposed outside of a protective encapsulant. The end faces of the device with the exposed anode extension(s) and cathode layer are flame sprayed and subsequently solderable to form terminals at both ends of the device. This applied terminal material is present only on the end faces of the device and does not have a significant presence on the bottom or mounting surface of the device. Additionally, the terminals cover the entire end faces of the device. This design represents a valve metal device with a multilayer ceramic capacitor (MLCC) device terminal structure. These terminal structures are undesirable in the art because they are not compatible with industry standard termination specifications for surface mount capacitors. Furthermore, such terminal structures are undesirable because the terminals span the entire width of the device. It is well known in the industry that mounting pads on a printed circuit board are narrower than the device terminals to help stabilize the device during the soldering process when mounting the device to a printed circuit board (PCB). If the terminals were to extend across the width of the device, the mounting pads on the PCB would be wider than the device, and the terminal structure would require more space on the PCB than the capacitive device could occupy, resulting in less than ideal volumetric efficiency. Thus, a device with terminals significantly narrower than the width of the device would require a mounting pad on the PCB that is narrower than the capacitive device, occupying less space on the PCB, resulting in greater volumetric efficiency of the PCB. The device preferably conforms to industry standards, and preferably the device terminals are 0.4 mm or narrower than the device case. As disclosed in References 1-3, terminal structures in which the terminals reach the top surface of the device are also undesirable due to the general state of modern electronic devices that exhibit RF transmission and electronic devices that are sensitive to external RF and EM interference, such as mobile phones, where a conductive metal ground shield is placed on the circuit board to mitigate such issues. In these devices, the shield may contact the top surface of the device mounted on the PCB.Thus, devices with terminals that extend all the way to the top of the device provide a potential electrical path between the terminals and the grounded shield, thereby rendering the device and circuitry inoperable.

[0006] Other methods of constructing surface mount solid electrolytic capacitors have been proposed, for example, in Reference 4, which is incorporated herein in its entirety. These teachings still result in poor volumetric efficiency. The focus is on the structure with performance improvements related to the impact on the electrical circuit. The design requires the attachment of anode and cathode extensions. These teachings describe terminals that are mechanically attached prior to encapsulation. As mentioned above, this takes up space within the encapsulant and reduces the volumetric efficiency of the device. Additionally, no attachment method is taught and one must assume that traditional attachment methods will be followed, which does not provide any advantage in volumetric efficiency.

[0007] In addition to the volumetric efficiency advantages gained from the anode and cathode attachment methods, the encapsulation method also plays a large role in the final volumetric efficiency of the device. Many methods are used in the art to create a thin wall of encapsulant over the active element to protect it from the environment. Traditional methods include injection molding around the element so that it floats in the injection mold cavity. This method fails to improve efficiency because features that are part of the process of suspending the element in the cavity must be large enough to support the element, resulting in incorporation into the device that takes up space not used for active capacitance. One example of a material that occupies this space is the leadframe. The leadframe must extend into the package to support the element, and its ability to support the element is related to its thickness. In addition, a method known as face-down supports one side of the leadframe, the opposite side from the capacitive element, against the mold cavity, reducing the thickness required to support the element. However, reducing the thickness of a face-down leadframe is limited by its ability to adhesively bond with the encapsulant and the thickness required to mechanically lock the leadframe to the encapsulant. If either of these aspects is neglected in an effort to increase volumetric efficiency, the external forces on the capacitor terminals will be directly transferred to the internal element, potentially causing damage. These factors limit the improvement of volumetric efficiency, especially near the thickness dimension of the device. In addition, the leadframe structure in a face-down design does not address the difficulty of controlling the encapsulant thickness on the side of the element opposite the face-down leadframe. This thickness is also controlled by the ability of the injection molding process to flow laterally between the capacitor surface and the cavity mold surface.

[0008] Injection molding is a process where resin is injected into a cavity that suspends a capacitance element. This suspension is usually done by supporting a portion of the conventional end of the lead frame, compressing the lead frame to a surface, as in face-down packaging, and placing the injection cavity on the opposite side of that surface. The challenge with this process is that the resin is presented to the cavity either directly within the capacitor cavity in the long aspect ratio area, or outside the capacitor cavity where the resin does not enter in the long aspect ratio area. If the resin is presented within a portion of the capacitor cavity, the portion of the resin that is in contact with the cavity portion of the device must be subsequently removed so that it does not become part of the finished device. This removal process can affect electrical performance and final dimensional target capability, and is even more difficult as the resin wall thickness decreases with miniaturization. In addition, the steps taken to remove this portion can add cost and complexity, especially when trying to control the final dimensions, which is an ongoing goal in the art. When the injected resin is presented outside the cavity, the primary process limitation is the ability of the resin to flow into a long aspect ratio cavity. As per the miniaturization goal, it is preferable to have as small a resin wall between the capacitive element and the outside environment as possible. For a standard capacitor in the industry, there may be regions of the cavity where the resin must flow for a length of 100 or more times the wall thickness to be injected. This long aspect ratio makes filling difficult due to back pressure resulting from the flow and its effect on other flow characteristics in the remainder of the cavity, which causes more mixing of the resin adjacent to the heated cavity mold, potentially risking premature hardening of the material.

[0009] It is possible to achieve process conditions and materials that allow for long aspect ratio filling between the cavity and the element, but as mentioned above, this typically requires high pressure to move the material across these long portions of the capacitive element, which can increase the cost and complexity of the materials used. This high pressure can also produce a series of undesirable characteristics. Since it is not practical to apply a uniformly balanced pressure when there are long aspect ratios on both sides of the capacitive element, the capacitive element can be biased to one side of the encapsulant. This bias moves away from the overall thickness potential of the final part, which typically requires a minimum encapsulant wall thickness. A further difficulty in processing parts with such long aspect fill ratios is that the pressure generated while the material is filling through the long aspect portions can stress the element, risking damage to the element or forcing it to move within the package, resulting in quality and / or efficiency defects.

[0010] Another method of achieving good filling at longer aspect ratios is to pre-fill the cavity with liquid resin, lower the cavity to a fixed height, and then force the liquid resin out of the cavity, leaving only the desired amount of resin defined by the lowering of the cavity and the other fixed parts of the cavity. The limitation of this method is that when trying to obtain very thin walls of the encapsulant, the manufacturing variation of each capacitive element limits the achievable wall thickness, since the encapsulant cavity thickness must be fixed at the maximum of the variation within the capacitive element to maintain the minimum wall thickness of each part. It is impractical to process each element with variable height control, and leaving a finished part with encapsulant walls that are too thin can cause defects in later processes.

[0011] Other methods disclosed include the use of resin sheets to deliver resin directly to portions of the encapsulant so that the resin does not have to traverse the long aspect ratio portions of the device, as described in Reference 5, which is incorporated herein in its entirety. This process helps reduce the effects of encapsulation resin migration because the resin is distributed over the capacitive element surface prior to pouring the resin into place. While this method helps reduce this stress during the encapsulation process, it does not allow for greater control over the encapsulant thickness since there is no way to control the final cavity dimensions that define the capacitor thickness.

[0012] A more recent method is described in Reference 6, which is incorporated herein in its entirety. In this teaching, a film is used in the encapsulant, and the resin is embedded in the film. Although beneficial, the capacitive elements move during the process, which undesirably requires additional space between the capacitive elements. Furthermore, it is difficult to reproducibly achieve sufficient coverage of the capacitive elements in the resin.

[0013] As discussed above, there is a continuing need for devices that have improved volumetric efficiency while maintaining the correct terminal configuration consistent with industry standards for valve metal surface mount capacitors. Despite significant efforts, improved volumetric efficiency and improved electrical performance of capacitors remains desirable. Such improvements are provided herein. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] U.S. Patent No. 6,819,546 [Patent Document 2] U.S. Patent No. 7,161,797 [Patent Document 3] US Patent Application Publication No. 2010 / 0165547 [Patent Document 4] U.S. Patent No. 5,601,020 [Patent Document 5] U.S. Patent No. 7595,235 [Patent Document 6] U.S. Patent No. 10,079,113 Summary of the Invention [Problem to be solved by the invention]

[0015] The present invention provides an improved capacitor and a method for making the improved capacitor. [Means for solving the problem]

[0016] A particular feature of the present invention is to provide an apparatus having a structure and a method of construction thereof in which the volume occupied by the encapsulant is significantly reduced without compromising the functionality of the capacitor, thereby improving volumetric efficiency.

[0017] Yet another embodiment is provided in a capacitor. The capacitor comprises an upper reinforcing encapsulant layer and a lower reinforcing encapsulant layer, with a capacitive element between the upper and lower reinforcing encapsulant layers. The capacitive element comprises an anode, a dielectric on the anode, and a cathode on the dielectric. An inner reinforcing encapsulant layer is provided between the upper and lower reinforcing encapsulant layers.

[0018] As a further example, forming a capacitive element comprising an anode, a dielectric on the anode, and a cathode on the dielectric; Providing an inner prepreg consisting of an upper prepreg, a lower prepreg, and a pocket; forming a layer structure of the upper prepreg and the lower prepreg in a form in which an inner prepreg is sandwiched between the upper prepreg and the lower prepreg and a capacitive element is disposed in the pocket; and compressing the layer structure and curing at least the resin to form a capacitor.

[0019] As a further example, forming a capacitive element comprising an anode, a dielectric on the anode, and a cathode on the dielectric; forming a layer structure of a capacitive element and at least one overload prepreg made of a film and a resin; and compressing the layer structure and curing at least the resin to form a capacitor.

[0020] As yet another example, there is provided an electronic component comprising an upper reinforcing encapsulant layer, a lower reinforcing encapsulant layer, and an electronic element disposed between the upper and lower reinforcing encapsulant layers. An inner reinforcing encapsulant layer is disposed between the upper and lower reinforcing encapsulant layers. [Brief description of the drawings]

[0021] [Figure 1A] FIG. 1A is a schematic diagram of a surface mount capacitor according to the prior art. [Figure 1B] FIG. 1B is a schematic diagram of a face-down, surface-mount capacitor according to the prior art. [Figure 1C] FIG. 1C is a schematic diagram of a substrate structure surface mount capacitor according to the prior art. [Figure 1D] FIG. 1D is a schematic diagram of a prior art surface mount capacitor with a resin sheet structure. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing one embodiment of the present invention. [Diagram 3] FIG. 3 is a cross-sectional schematic diagram showing an intermediate stage of one embodiment of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view showing one embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic exploded view showing one embodiment of the present invention. [Figure 6] FIG. 6 is a schematic cross-sectional view showing one embodiment of the present invention. [Figure 7] FIG. 7 is a schematic cross-sectional view showing one embodiment of the present invention. [Figure 8]FIG. 8 is a schematic cross-sectional view showing one embodiment of the present invention. [Figure 9] FIG. 9 is a schematic cross-sectional view showing one embodiment of the present invention. [Figure 10] FIG. 10 is a schematic cross-sectional view showing one embodiment of the present invention. [Figure 11] FIG. 11 is a schematic cross-sectional view showing one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The present invention provides electronic components, particularly capacitors, with improved volumetric efficiency and methods for their manufacture. The methods include an improved method for controlling the encapsulant wall between the electronic elements of the electronic component and the outer surface of the encapsulant by using prepregs. The prepregs may contain extra resin or may be pocketed. In one embodiment, the pockets may be stabilized with additional prepregs that are planar or serpentine.

[0023] The present invention will now be described with reference to the various drawings which form an essential, but non-limiting, component of this specification, and in which like elements are correspondingly referenced throughout the various drawings.

[0024] FIG. 1A shows a schematic cross-sectional view of a prior art surface mount capacitor 1. In FIG. 1A, an anode 2 has an anode lead 3 extending therefrom. The anode lead is electrically connected, typically by a weld 9, to an anode lead frame 4. At least a portion of the anode is provided with a dielectric 5 separating the anode from the cathode 6. The cathode is electrically connected to a cathode lead frame 7 by a conductive adhesive 11, and the entire structure, except for the contact portions of the anode and cathode lead frames, is encapsulated with a non-conductive encapsulant 8. The anode lead frame 4 and cathode lead frame 7 preferably occur as part of a substantially continuous lead frame in the form of an array in which multiple anode and cathode leads are integrated into a common lead frame, as is well known in the art. When the capacitor is integrated, such as by dicing, the anode and cathode leads are electrically disconnected.

[0025] FIG. 1B shows a schematic cross-sectional view of a prior art face-down surface mount capacitor 50. In FIG. 1B, an anode 51 has an anode lead 53 extending therefrom. The anode lead is electrically connected, typically by welding, to an anode lead frame tab 55. A dielectric 56 is provided over at least a portion of the anode, separating the anode from the cathode 57. The cathode is electrically connected to a cathode lead frame 58 by a conductive adhesive 59, and the entire structure, except for the contact portions of the anode and cathode lead frames, is encapsulated in a non-conductive encapsulant 60. The anode lead frame 61 and cathode lead frame 58 preferably occur as part of a generally continuous lead frame in the form of an array, with multiple anode and cathode leads integrated into a common lead frame, as is well known in the art. When the capacitor is integrated, such as by dicing, the anode and cathode leads are electrically separated.

[0026] FIG. 1C shows a schematic cross-sectional view of a prior art surface mount capacitor 100 on a substrate 116. In FIG. 1C, an anode 101 has an anode lead 103 extending therefrom. The anode lead is electrically connected, typically by welding, to an anode spacer 105. At least a portion of the anode is provided with a dielectric 106 separating the anode from a cathode 107. The cathode is electrically connected to an internal cathode pad 109 by a conductive adhesive 108. The internal cathode pad 109 is electrically connected to an external cathode terminal 110 by a cathode electrical pathway 111, typically formed by plating a hole in the substrate 112. The internal anode pad 113 is electrically connected to an external anode terminal 114 by an anode electrical pathway 115, typically formed by plating a hole in the substrate 112. The anode spacer 105 is electrically connected to the anode lead 103, which is electrically connected to the internal anode pad 113, typically by welding or soldering. The entire structure, except for the substrate assembly 116 consisting of the internal anode and cathode pads, external anode and cathode terminations, anode and cathode electrical paths, and substrate, is encapsulated with a non-conductive encapsulant 117. At least a portion of the internal anode and cathode pads and a portion of the substrate are in contact with the non-conductive material to form a device with portions of the external anode and cathode terminations exposed at the bottom surface of the device.

[0027] FIG. 1D shows a schematic cross-sectional view of a prior art resin sheet structure surface mount capacitor 150. In FIG. 1D, an anode 151 has an anode lead 153 extending therefrom. A dielectric 156 is provided over at least a portion of the anode, separating the anode from the cathode 157. A capacitive element is comprised of the anode, the anode lead, the dielectric, and the cathode. The capacitive element is encapsulated with a non-conductive adhesive consisting of two resin layers, a top resin layer 159 and a bottom resin layer 160. A hole 161 is formed in the bottom resin layer 160 for the cathode 157 and is metallized to form an electrical connection 152 between the cathode 157 and an external cathode terminal 163. A hole 162 is formed for the anode lead 153 and is metallized to form an electrical connection 158 between the anode lead 153 and an external anode terminal 164.

[0028] The prior art assemblies illustrate typical construction methods for solid electrolytic valve metal capacitors that utilize lead frames or plated terminations to terminate the device. The device according to the present invention is intended to be a direct replacement for the prior art and therefore preferably matches the prior art termination configuration while improving volumetric efficiency. Additionally, the device according to the present invention is suitable for use in combination with a wider array of electronic elements, thereby providing a wider selection of electronic components with improved volumetric efficiency.

[0029] FIG. 2 is a schematic diagram of one embodiment of the present invention showing steps of forming an electronic component using an electronic element by forming a capacitor from a capacitive element as an electronic element, without being limited thereto. A shows a partially exploded view of the steps, and B shows the completed view. In FIG. 2, a capacitive element 200 is shown representing an electronic element, which comprises an anode, preferably a valve metal anode, with an anode lead 203, represented as an anode wire, extending therefrom. A dielectric is provided over at least a portion of the anode, which separates the anode from the cathode. The anode, dielectric, and cathode are well known and are not separately shown. The anode lead 203 is connected, typically by welding, to an anode lead frame tab 206. The anode lead frame tab 206 is connected to or integral with an anode lead frame 207. The cathode is the outer casing of the capacitive element 200 and is electrically connected to a cathode lead frame 208, typically by a conductive adhesive 209. The overloaded prepreg 210, with the resin 214 integrally embedded in the film 212, is eventually pressed and cured to form the reinforced encapsulant 216, as described more particularly herein. By utilizing an overloaded prepreg, the amount of resin available to encapsulate the capacitive element may be sufficient to form the resin encapsulant 211 after processing, and the resin and film present in the film layer form the reinforced encapsulant 216 and the resin encapsulant layer 211, which combine to form the encapsulant.

[0030] In Fig. 2, the electronic element is a capacitive element, a resistive element, a varistor element, an inductive element, a diode, a fuse, an overvoltage discharge element, a sensor, a switch, an electrostatic discharge suppression element, a semiconductor or an integrated circuit, preferably a capacitor. The electronic element comprises leads and has a function between the leads. The electronic element is represented as a cathode, and the function between the leads is a capacitive coupling. Those skilled in the art will appreciate that other elements have different functions between the leads and can be readily substituted for the capacitive element throughout this specification and drawings.

[0031] A prepreg is a composite material consisting of a membrane that has been previously impregnated with resin. The membrane may be regular, such as a woven membrane, or random, such as a nonwoven membrane. The membrane preferably consists of regular or random fibers. The fibers are usually made of glass, but may be made of other materials such as carbon fiber, cellulose, etc., and may be of the same material as the resin, with a preference for the fibers to be at least partially cured. The resin is preferably a thermoplastic or thermosetting resin, preferably uncured or only partially cured. Prepregs are usually formed in layers and compressed before being cured, the resin and, if necessary, the membrane, preferably being fully cured. Conventional prepregs have enough resin to impregnate the entire membrane, and when compressed, the resin is released from the membrane before it hardens.

[0032] For the purposes of the present invention, an overloaded prepreg is a prepreg consisting of an excess of resin, where the volume of the resin before compression or curing is greater than the volume of the membrane area including the resin incorporated in the membrane. After the formation of the capacitor, the volume occupied by the membrane may be the same as that of a normal prepreg, which is essentially the volume of the membrane, or it may be slightly compressed. The excess resin of the overloaded prepreg impregnates the membrane and forms a resin encapsulation 211 that occupies at least a portion of the area around the capacitive element and associated connection components, and preferably the entire area around the capacitive element and associated connection components. The resin also impregnates the membrane after completion to form a reinforcing encapsulant 216. The thickness T of the reinforcing encapsulant 216 after compression and curing is equal to the thickness T of the overloaded prepreg. 2 The excess resin of the overloaded prepreg forms at least a part of the resin encapsulation portion 211.

[0033] In a particularly preferred embodiment, the overloaded prepreg has a thickness T 1 A thickness T that is at least 110% of 2The overload prepreg is made of a sufficient amount of resin to represent the thickness of the capacitive element corresponding to the electronic element and its associated connection components. Thus, the excess resin impregnates the film and fills around the capacitive element corresponding to the electronic element and its associated connection components. More preferably, the resin occupies at least 125% of the thickness of the film before full curing. Even more preferably, the resin occupies at least 150% of the thickness of the film before full curing. During preparation of the electronic component, the overload prepreg is compressed and cured.

[0034] FIG. 3 illustrates generally one embodiment of the present invention in which an electronic component, represented as a capacitor 250, is shown at an intermediate stage in the manufacturing process. In FIG. 3, an anode 251, preferably a valve metal anode, has an anode lead 253 extending therefrom. A dielectric 255 is provided over at least a portion of the anode and separates it from a cathode 256. A top reinforcing encapsulant 257 and a bottom reinforcing encapsulant 258 are disposed on opposite sides of the capacitive element in a sandwiched relationship. The top and bottom reinforcing encapsulants are preferably formed from overload prepregs. The reinforcing encapsulants sandwich a capacitive element, representing the electronic element, which is also partially encapsulated in a resin encapsulant 259. At least a portion of the resin in the resin encapsulant is from excess resin in the overload prepregs. The top and bottom stiffening encapsulants 257 and 258 cooperate with the resin encapsulant 259 to at least partially encapsulate the capacitive element consisting of the anode, anode lead, dielectric, and cathode, forming a pocket or cavity in which the encapsulants are received during molding. Terminations designated as external anode terminal 260 and external cathode terminal 261 are bonded to the bottom stiffening encapsulant 258. Anode and cathode holes 263 and 262 are formed in the corresponding external anode and cathode terminals, respectively, and extend through the bottom stiffening encapsulant and the resin encapsulant. Anode hole 263 is formed in, and preferably extends through, the anode lead 253, designated as the anode wire, toward the top stiffening encapsulant. A metallization 267 is formed in the anode hole and bonded to the resin encapsulant 259 so that the anode lead is electrically connected to the external anode terminal. The metallization electrically connects the anode lead along orthogonal cuts of the anode lead to maximize the electrical connection area without increasing the hole size along the length of the anode lead. Alternatively, the anode hole can be open to the metal of the anode, and the metallization of the anode hole directly electrically connects the anode and provides electrical connection to the external anode terminal. The metallization can be a single metal, an alloy, or a continuous series of metals to provide sufficient electrical conductivity.In this alternative embodiment, an anode lead may or may not be provided, and preferably is not provided to further improve volumetric efficiency. A cathode hole 262 is formed through a portion of the cathode 256. This portion may be formed from the cathode layer of the capacitor element, or may be formed from a material suitable for electrical connection attached to the cathode layer. The cathode hole 262 is metallized to form an electrical connection between the cathode and an external cathode terminal. Lines 264 and 265 represent a preferred embodiment of the invention, the lines representing the portion of the device that is cut to form a device having a defined length. The cutting process, typically dicing, preferably exposes a portion of the metallized holes 262 and 263, thereby forming the end terminations of the capacitor after cutting, as can be seen from FIG. 4.

[0035] FIG. 4 shows the embodiment of FIG. 3 in schematic form after cutting. In FIG. 4, the electronic component is represented as a capacitor 250 having an anode 251, preferably a valve metal anode, with an anode lead 253, represented as an anode wire, extending therefrom. A dielectric 255 is provided over at least a portion of the anode, separating it from a cathode 256. A top reinforcing encapsulant 257 and a bottom reinforcing encapsulant 258 are disposed on opposite sides of the capacitive element in a sandwiched relationship. These reinforcing encapsulants position the capacitive element within a resin encapsulant 259, with the top reinforcing encapsulant 257, bottom reinforcing encapsulant 258, and resin encapsulant 259 acting together to at least partially encapsulate the capacitive element. Preferably, but not necessarily, the top reinforcing encapsulant 257, bottom reinforcing encapsulant 258, and resin encapsulant 259 are comprised of a common resin, with the resin permeating one or both membranes. The resin may further comprise multiple resin systems, such as the use of blends or copolymers of multiple resins. Also, in one non-limiting embodiment, it is further preferred that the resin forming the lower reinforcement encapsulant 258 emanates from the membrane layers to fill the periphery of the capacitive element between the membranes. The external anode terminal 261 and the external cathode terminal 260 are bonded to the resin encapsulant 259. The remaining portions of the anode hole 263 and the cathode hole 262, as well as the metallization contained therein, form conductive leads on the surface of the capacitor and may function as circuit traces to connect to additional features integrated with or provided on the encapsulant.

[0036] An embodiment of the present invention will be described with reference to FIG. 5. In FIG. 5, an exploded view of the layer assembly is shown. The layer assembly consists of a lower prepreg 300 and an upper prepreg 302, which may be of the same composition. At least one of the lower prepreg or the upper prepreg may be an overload prepreg. The pocket layer 304 consists of a pocket 306 and is suitable for receiving therein the electronic element 200 and the termination represented as a wire 203. The pocket layer may be a prepreg, preferably a partially cured resin layer, or a membrane and resin. The pocket layer may be an overload prepreg. An optional auxiliary resin layer 305, which does not constitute a membrane, may be provided between the lower prepreg and the pocket layer, or between the upper prepreg and the pocket layer, to provide additional resin in case the upper prepreg or the lower prepreg does not have enough resin to completely fill the void around the electronic element. The pocket layer is preferably not thicker than the thickness of the capacitive element, and more preferably the pocket layer is thinner than the thickness of the capacitive element. The layered assembly is compressed and at least the resin hardens resulting in a structure which will be described in more detail with reference to Figure 6. Preferably, the pocket does not contribute electrically to the electrical function of the electronic device.

[0037] FIG. 6 is a cross-sectional view of one embodiment of curing perpendicular to the anode wire 203 extending from the electronic element depicted in the capacitive element 200. The top prepreg is compressed and cured to form the reinforcing encapsulant layer 308, and the bottom prepreg is compressed and cured to form the reinforcing encapsulant layer 310. An optional but preferred inner reinforcing encapsulant layer 312 is formed parallel to the outer reinforcing encapsulant layers 308 and 310 when the pocketed layer is a prepreg or overloaded prepreg. Although it is preferred that the inner reinforcing encapsulant layer be substantially parallel, manufacturing constraints preclude such ideal parallelism. It should be understood that there may be undulations in the inner reinforcing encapsulant layer due to irregular resin flow. A resin encapsulant 314 encapsulates the capacitive element and the anode wire. The resin encapsulant may be formed from resin of the top prepreg, the bottom prepreg, or the auxiliary resin layer.

[0038] One embodiment of the present invention is shown in FIG. 7, where a cured embodiment is shown in cross section. In FIG. 7, a prepreg or overloaded prepreg film is provided with voids 315, which provide resin-filled voids 316 that can be used to form vias for electrical connection to the anode or cathode of a capacitive element. It is preferred, but not limited to, to provide voids in the prepreg before encapsulation. Generally, it can be said that the resin fills the voids in the prepreg after lamination. Since the voids are created before encapsulation, there is no film in the void area.

[0039] 8 shows one embodiment of the present invention in which multiple reinforcing encapsulant layers 308 and 310 and multiple inner reinforcing encapsulant layers 312 are formed around an electronic element represented as a capacitive element 200. An optional auxiliary resin layer 305 provides additional resin when the resin provided with the prepreg is insufficient to fill the area.

[0040] An embodiment of the present invention is described with reference to FIG. 9, in which an electronic component represented as a capacitor is shown in a cross-sectional schematic view. In FIG. 9, at least one reinforced encapsulant layer 308 and 310 is provided on either side of the body of the electronic element, both reinforced encapsulant layers being substantially planar. An inner serpentine reinforced resin encapsulant 318 extends at least partially around the electronic element 200, thereby forming a reinforced encapsulant pocket in which the electronic element resides. The inner serpentine reinforced encapsulant layer can be formed from a resin and film prepreg, or an overload prepreg, as described herein. The serpentine reinforced resin encapsulant can be formed over a previously placed capacitive element or a sacrificial feature that is subsequently removed. Alternatively, the serpentine prepreg or overload prepreg can form a pocket, and the electronic element can be placed in the pocket before compression and curing. The serpentine reinforced resin layer can also be formed from a non-woven or non-continuous film material. Non-continuous fibers can be used to form a serpentine path that is substantially perpendicular to the reinforced encapsulant layers 308 and 310. Preferably, the reinforcing resin encapsulant does not contribute to an electronic function, but may provide other electrical or physical functions as discussed further herein. It may also be preferred that no resin encapsulant 308 or 310 is provided, such that 318 provides a space between the electronic element 200 and the external device surface.

[0041] FIG. 10 is a cross-sectional view of a cured embodiment of an electronic component represented as a capacitor. FIG. 10 is shown orthogonal to the anode wire 203 extending from the capacitive element 200. In FIG. 10, at least one of the reinforcing encapsulant layers, such as reinforcing encapsulant layers 308 and 310, incorporates an optional internal metal layer 320, thereby providing a physical or electrical function to the reinforcing encapsulant layer. The internal metal layer may provide physical properties to the capacitor, such as shielding electromagnetic interference, heat dissipation, reducing moisture transmission, or other advantageous properties. The internal metal layer may be electrically isolated from the capacitive coupling and associated terminations. In another example, the internal metal layer may be functionalized, such as to provide resistance or to act as a fuse, in which case it may be electrically connected to an external termination. In another example, the internal metal layer may be separately terminated to protect against surface ionization and thereby suppress arcing, or to dissipate heat.

[0042] FIG. 11 is a cross-sectional view of one embodiment of the cured orthogonal to the termination represented as anode wire 203 extending from the electronic element represented as capacitive element 200. In FIG. 11, an optional surface metal layer 322 is incorporated on at least one of the reinforcing encapsulant layers 308 and 310. The surface metal layer can provide physical properties to the electronic element such as electromagnetic interference shielding, heat dissipation, reduced moisture transmission, and other advantageous properties. The surface metal layer may be electrically isolated from the capacitive coupling and associated termination. In another example, the surface metal layer may be functionalized, such as to provide resistance or to act as a fuse, in which case it may be electrically connected to an external termination. In another example, the surface metal layer may be separately terminated to protect against surface ionization and thereby suppress arcing. The surface metal layer may be integral with the prepreg or overload prepreg, or may be provided by a metallization such as a plating process.

[0043] In a preferred embodiment, the capacitor comprises at least one anode comprised of a valve metal or a conductive oxide of a valve metal and an anode wire. A dielectric is formed over the anode and a cathode layer is formed over the dielectric. The capacitive element is attached to a lead frame, the anode lead wire is electrically attached to the lead frame on the anode portion of the lead frame and the cathode of the capacitive element is attached to the cathode portion of the lead frame, typically by a conductive adhesive. Prepreg is provided between the external capacitor device surface and the capacitive element on two opposing sides of the device such that a film of prepreg provides a consistent thickness of encapsulant across the thickness dimension of the capacitor device.

[0044] In manufacturing a capacitor, the capacitive element and lead frame are placed into an encapsulant-forming cavity with the prepreg disposed on at least one, preferably opposing sides, of the capacitive element and lead frame such that the prepreg film contacts the encapsulant-forming cavity in the thickness direction of the device.

[0045] The area of ​​the mold cavity that forms a restriction for the encapsulant to flow during encapsulation is further referred to as the encapsulant forming cavity. This cavity can form any side of the device by restricting the flow of the encapsulant. Similar to the prepreg membrane, this cavity can also function as the portion of the encapsulant cavity that contacts the prepreg membrane and define the external location of any of the device's exterior surfaces. This is similar to what is known as the molding mold cavity wall. In some of the cavities, the device exterior surface is formed by the cavity interior shape. While this is in terms of a conventional molding mold cavity, the encapsulation molding cavity can be a surface such as a plate or a series of connected surfaces that form only a portion of the device's exterior surface.

[0046] The present invention provides a defined and repeatable thickness for the encapsulated capacitor. By utilizing a prepreg and contacting the surface of the capacitive element and the mold cavity, the prepreg film effectively cooperates with the surface of the capacitive element to form a cavity in which the encapsulant is constrained during molding while ensuring that the capacitive element is properly positioned within the encapsulant. In the orientation in which the prepreg film is not provided, the encapsulant may be constrained by the injection molding cavity. By exposing the conductive components of either the anode or the cathode, the terminations that make electrical contact with the anode or the cathode can be surface-attached onto the encapsulant, thereby reducing the thickness of the electrical connection. The use of the prepreg film can reduce the thickness of the encapsulant and define and fix the thickness of the finished capacitor. In such devices, the prepreg film provides a portion of the device thickness, but the encapsulant can still be formed in the cavity and compressed onto or into the device during the encapsulation process to achieve a predetermined thickness dimension.

[0047] In a preferred embodiment, a prepreg is provided between the cathode and the external copper, the prepreg being in physical contact with the capacitive element. After compression and curing of any sandwiched structure, a hole is formed through the copper and encapsulant, the hole intersecting the cathode of the capacitive element. Another hole is formed through the encapsulant layer and through the anode lead. The hole is preferably formed from the same side of the external copper. The hole is metallized by plating that adheres to the encapsulant, forming an electrical connection between the orthogonal surface of the anode lead and the external copper. A similar metallized hole forms an electrical connection between the cathode of the capacitive element and the external copper. The external copper is preferably etched in a pattern that electrically disconnects the anode and cathode portions on the device surface to form terminals. The copper is subsequently treated to provide a solderable surface.

[0048] In one embodiment, a capacitor is provided that includes a metallized hole in at least the anode portion of the capacitor. The metallized hole is partially exposed through a sawing process, thereby providing a solderable surface for each terminal connection area, which is on a different side of the capacitor than the terminal portion of the device. It is known in the industry that surface mount capacitors have a metallized surface on a surface other than the terminal surface that is orthogonal toward the mounting surface to form a solder fillet surface where the solder used to attach the terminal to the circuit board can form the side of the capacitor. This allows visual confirmation of successful soldering and facilitates rework of the device. Additionally, the solder fillet creates a balance of forces on both ends of the capacitor during the solder reflow process, keeping the component centered in the desired circuit board space. The exposed portion of the metallized hole is held together with the device in such a manner that the entire connection between the metallization and the anode lead is intact. As with the prior art description where the holes are only formed in the anode lead, it is not practical to retain the entire connection to the anode lead while exposing the metallized connection on both sides of the device. To expose a portion of the metallized hole to improve volumetric efficiency, it is necessary to remove at least a portion of the anode lead that connects with the metallization layer. Removing any portion of the metallized connection to the anode lead will impair electrical performance. Furthermore, the use of molded holes with metallization formed therein makes it more efficient to manufacture capacitors with solderable surfaces perpendicular to the terminal surface. Users of surface mount capacitors typically desire a solderable surface on the perpendicular surface of the device that is less in width than the width of this surface in any direction. The present invention allows this aspect to be controlled by the dimensions of the depth and width of the hole that is formed to be metallized. In other methods in the art, this metallization between the anode lead and the terminal can only be formed on the entire perpendicular surface of the device. This is undesirable to users due to a number of factors, including the possibility of shorting the device and improper soldering of the device. In some situations, it may be preferable to provide connection surfaces on multiple surfaces of the capacitor simultaneously, including the top and bottom.By forming metallized holes and then controlling the removal of portions of copper, this metallization can be formed on any surface and in controlled configurations such as traces or patterns as desired.

[0049] The membrane can be any layer that limits the thickness of the encapsulation resin with sufficient processing, and a portion of the encapsulation resin is bonded during processing on at least two sides, one side being the encapsulant-forming cavity and the other side being the surface of the capacitive element, such that the membrane limits the penetration of the encapsulant-forming cavity into the surface of the capacitive element.

[0050] An encapsulant-forming cavity is any surface that, when subjected to the encapsulation process, acts as a barrier to the encapsulant and forms an exterior surface that encapsulates at least a portion of the capacitive element when the device is removed from the cavity.

[0051] In one embodiment, the prepreg or overloaded prepreg membrane is porous, allowing the encapsulant to permeate through the membrane layer, which can contact the capacitive element surface on one side and the encapsulant-forming cavity on the other side. The porous membrane is made of reinforcing or filler materials such as woven glass, fibers, etched materials, or loose particles, all of controlled thickness.

[0052] In one embodiment, the membrane consists of a solid film that may be impregnated with or adhered to the encapsulating resin.

[0053] In one embodiment, the membrane is compressible. The compressible membrane can provide a certain minimum distance between the surface of the capacitive element and the encapsulant forming cavity in a compressed state and can be held in the compressed form by the encapsulant or can be allowed to spring back. The compressible membrane serves to reduce the force acting on the capacitive element while providing a more uniform force distribution across the capacitive element or parallel capacitive elements in the same encapsulant forming cavity such that the capacitive element is held within a certain distance from the encapsulant forming cavity.

[0054] Film layers can be applied to multiple surfaces of a capacitive element, taking advantage of the thickness-limited nature of the film to accommodate device dimensions other than thickness.

[0055] In some embodiments, an adhesive or encapsulant may be provided between the capacitive element and the membrane, thereby adhering the membrane to the capacitor surface, the resin or adhesive portion fixing the membrane to the capacitor surface and thereby also serving as part of the membrane thickness limiting function.

[0056] Generally, if a certain thickness is obtained between the cavity and the capacitive element, it is not necessary for all surfaces of the film and the capacitive element to be restricted by the prepreg film.

[0057] The holes formed for the anode connection preferably have a sufficient depth and cross-sectional area to provide an exposed anode lead by forming a hole through, preferably completely through, the anode lead, rather than reaching the closest point of the anode lead. By forming a hole through the anode lead, a cross-sectional portion of the anode lead is exposed, allowing the electrical contact area of ​​the metallization on the anode lead to be increased without increasing the length of the anode lead along one direction, thereby improving the volumetric efficiency of the device by achieving a larger contact area without significantly occupying the length of the device. Another preferred advantage of forming through holes in the anode lead is that this process allows multiple anode leads to be connected through the same through hole, thereby providing a common metallization for a group of capacitors. Providing multiple anodes, and therefore anode leads, in a common package is advantageous when additional capacitance or resistance reduction is required. It is also preferred, but not required, that the holes formed in the cathode portion of the device penetrate the cathode to enhance this connection. The cathode layer typically traverses most of the length and width of the anode, thus increasing the surface area contacted during metallization without compromising volumetric efficiency.

[0058] The holes are formed by any technique known in the art, and the metallization is achieved by a method selected from plating, sputtering, vapor deposition, sintering, diffusion, coating, and applying a conductive material, preferably a metal, into the holes.

[0059] The cathode layer is not limited herein and is consistent with those commonly found in the capacitor industry, including a cathode layer made of a conductive polymer or manganese dioxide on the anode dielectric. The conductive polymer layer can be formed by many methods well known in the art, such as in situ polymerization, one-pot polymerization, electrochemical polymerization, or prepolymerized polymer dip. Particularly preferred conductive polymers are polyaniline, polypyrrole, polythiophene and its derivatives. The preferred polymer for demonstrating the present invention is poly-3,4-ethylenedioxythiophene. An additional cathode layer is preferably formed on the conductive polymer layer or manganese dioxide layer to facilitate connection thereto, with carbon-containing and metal-containing layers being particularly suitable for demonstrating the present invention. The carbon-containing layer typically contains conductive carbon in a resin. The metal-containing layer typically includes a metal-loaded resin layer, an example of which is a silver flake-containing resin, or the metal-containing layer may be metal-plated. The cathode layer is preferably formed by metal plating, as this simplifies the process of metallizing the cathode layer in the cathode hole. Metal foil may also be incorporated into the cathode. The metal foils can be attached to the other cathode layers by a variety of electrical and physical attachment methods, including but not limited to conductive adhesives, soldering, brazing, or welding. These cathode foils act as part of the cathode that provides electrical current to and from the inner cathode layers. The cathode foils are preferably made of metals such as, but not limited to, copper, silver, stainless steel, or other conductive materials.

[0060] Terminals on the exterior surface of a device are employed to provide electrical connections between the device and electrical circuits. Terminals are typically made of metal that can be attached by methods common in the industry, including but not limited to soldering, wire bonding, brazing, welding, ultrasonic attachment, copper post bonding, and the like. Terminals are typically formed as lead frames in some embodiments, or as layers that are part of the device on the exterior surface of the device, such as formed by metal foils or plating in other examples. The most preferred metal for the terminals is copper due to its electrical conductivity and other processing advantages, but other metals or materials can serve as the terminal material or part of the terminal material, including but not limited to nickel, stainless steel, metal-filled polymers, conductive polymers, and the like. Terminals are typically square to meet industry standards for placement at soldering locations on a PCB, but this is not a limitation of the invention. Terminations allow electrical paths to be provided between one or more portions of the exterior surface of the device and other portions of the exterior surface of the device. These are known in the industry as traces. Electrical paths are formed on the surface of the device to connect portions of the metallization that connect to the capacitive elements inside the encapsulant with other portions or surfaces of the encapsulant where terminals may be provided. Providing these traces can simplify or provide electrical benefits by forming holes for the metallization in one portion of the device while providing terminals on other portion(s) of the device, whether or not the traces are also part of the connection portion of the terminals.

[0061] It is well known to those skilled in the art that additional processing of the valve metal may be required to form a sufficient metallization on the valve metal. In some cases, this is part of the metallization technique and is not evident on the device as only the valve metal and metallization are evident. In some cases, the valve metal is difficult to metallize and additional steps and materials are required to prepare the valve metal. In such cases, a portion of the anode, preferably but not limited to the anode lead, is treated to form a metallographic bond to the valve metal with a material that is compatible with the hole metallization. This treatment can form an electrical bond layer that promotes the electrical adhesion performance of the metallization to the valve metal. It is also preferable to attach a material, the anode node, to the anode lead using methods well known in the industry, such as welding, brazing, soldering, gluing, sintering, etc. This anode node provides the material of the hole metallization to form a stable electrical connection and makes electrical contact with the anode lead in a beneficial manner by removing the usual lead frame.

[0062] It will be understood by those skilled in the art that the internal metal layers will not be formed in a position or configuration that intersects the metallization of the anode or cathode terminations unless they are configured as part of a circuit. This can prevent shorts from occurring within the device, however, if the internal metal layers are formed to cooperate with the anode or cathode terminations, it may be preferable for one or more metallization layers to intersect the internal metal layers. This can be accomplished by preforming the internal metal layers prior to encapsulation, etching away portions of the metal layers, or similar processes. The internal metal layers may cover only a portion of the surface area of ​​the completed device, depending on the requirements of the structure and terminal design. It is also contemplated that the internal metal layers may be undulating or serpentine to cover additional surface area of ​​the capacitor elements. The metal layers may provide electrical or physical aspects of the final device. In this manner, the internal metal layers may be exposed or electrically connected to the metallization layers, the combination of which may form external terminals that may be soldered or otherwise attached to a circuit board.

[0063] It is well known to those skilled in the art that encapsulants are typically formed from a resin and a filler. The filler provides a way to control the thermal expansion coefficient by replacing a portion of the resin in the encapsulant structure. It is noted that although this is a common technique for encapsulation, the present invention is not limited to the encapsulant being a resin or a resin-filled system. Other encapsulation materials and methods are also applicable to the present invention.

[0064] The anode is a conductor, preferably a metal, more preferably a valve metal selected from tantalum, aluminum, niobium, titanium, zirconium, hafnium, alloys of these elements, or conductive oxides such as NbO.

[0065] The present invention has been described with reference to preferred embodiments, but is not limited thereto. Additional embodiments and improvements may be realized that are not specifically described herein, but which are within the scope of the invention as particularly described by the appended claims.

Claims

1. an upper reinforcing sealant layer; a lower reinforcing sealant layer; A capacitive element provided between the upper reinforcing encapsulant layer and the lower reinforcing encapsulant layer, the capacitive element comprising: An anode; a dielectric on the anode; a cathode on the dielectric; and an inner reinforcing sealant layer disposed between the upper reinforcing sealant layer and the lower reinforcing sealant layer, the inner reinforcing sealant layer comprising a membrane; A capacitor comprising:

2. The capacitor according to claim 1 , further comprising a resin that encapsulates at least a portion of the capacitive element.

3. The capacitor of claim 1 , wherein the inner stiffening encapsulant layer is planar.

4. The capacitor of claim 1 , wherein the inner reinforcing encapsulant layer is serpentine.

5. The capacitor of claim 1 , wherein the inner stiffening encapsulant layer includes a cavity with the capacitive element within the cavity.

6. The capacitor of claim 5 further comprising an inner reinforcing encapsulant layer serpentine at least partially around the cavity.

7. The capacitor of claim 1 further comprising at least one additional inner reinforcing encapsulant layer.

8. The capacitor of claim 1 further comprising at least one additional upper reinforcing encapsulant layer or at least one additional lower reinforcing encapsulant layer.

9. 10. The capacitor of claim 1, further comprising at least one resin layer between the upper and inner reinforcing encapsulant layers or between the lower and inner reinforcing encapsulant layers.

10. The capacitor of claim 1 further comprising at least one anode lead in electrical contact with the anode.

11. The capacitor of claim 10 wherein the electrical contact is made to an anode node that contacts the anode lead.

12. The capacitor of claim 10 , wherein the anode lead is an anode wire.

13. The capacitor of claim 1 further comprising an anode termination on a surface of the capacitor, the anode termination being in electrical contact with the anode.

14. The capacitor of claim 13 , wherein the electrical contact comprises a metallized hole.

15. The capacitor of claim 14 wherein the metallized hole extends through an anode lead.

16. 16. The capacitor of claim 15, wherein the anode lead is an anode wire.

17. The capacitor of claim 14 , wherein the metallized holes are exposed on a surface of the capacitor.

18. The capacitor of claim 1 further comprising at least one of an anode or a cathode termination.

19. 20. The capacitor of claim 18, wherein at least one of the anode termination or the cathode termination is exposed through a surface of the encapsulant.

20. 20. The capacitor of claim 18, wherein at least one of the anode termination or the cathode termination is on at least one surface of the encapsulant.

21. 21. The capacitor of claim 20, wherein the cathode termination is in electrical contact with the cathode.

22. 10. The capacitor of claim 1, comprising a plurality of capacitive elements.

23. The capacitor of claim 1 , wherein the cathode comprises at least one of a conductive polymer or a conductive metal oxide.

24. 10. The capacitor of claim 1, wherein the anode comprises a valve metal or a conductive oxide of a valve metal.

25. 25. The capacitor of claim 24, wherein the valve metal or valve metal oxide is selected from the group consisting of Al, W, Ta, Nb, Ti, Zr, Hf and conductive oxides thereof.

26. The capacitor of claim 1 further comprising a plating layer in electrical contact with one of the cathode or the anode.

27. 27. The capacitor of claim 26, wherein the plating layer is a circuit trace.

28. 27. The capacitor of claim 26, wherein at least one of the upper reinforcing encapsulant layer or the lower reinforcing encapsulant layer is between the cathode and the plating layer.

29. The capacitor of claim 1 , wherein at least one of the upper reinforcing encapsulant layer or the lower reinforcing encapsulant layer further comprises an inner metal layer.

30. 30. The capacitor of claim 29, wherein the inner metal layer is electrically connected to an outer termination.

31. 30. The capacitor of claim 29, wherein the inner metal layer is electrically insulated from at least one of the anode or the cathode.

32. The capacitor of claim 1 further comprising a surface metal layer on at least one of the upper reinforcing encapsulant layer or the lower reinforcing encapsulant layer.

33. An anode; a dielectric on the anode; forming a capacitive element comprising: a cathode on the dielectric; Providing an inner prepreg including a pocket, an upper prepreg, and a lower prepreg; forming a layer structure of the upper prepreg, the lower prepreg, the inner prepreg between the upper prepreg and the lower prepreg, and the capacitive element in the pocket; compressing the layer structure and curing at least the resin to form a capacitor; 13. A method of forming a capacitor comprising:

34. 34. The method of forming a capacitor of claim 33, wherein at least one of the top prepreg, the bottom prepreg, or the inner prepreg is an overload prepreg.

35. 35. The method of forming a capacitor of claim 34, wherein the overload prepreg has a thickness of the resin greater than a thickness of the film.

36. 36. The method of forming a capacitor of claim 35, wherein the thickness of the resin is at least 110% of the thickness of the film.

37. 37. The method of forming a capacitor of claim 36, wherein said thickness of said resin is at least 125% of said thickness of said film.

38. 38. The method of forming a capacitor of claim 37, wherein said thickness of said resin is at least 150% of said thickness of said film.

39. 34. The method of forming a capacitor according to claim 33, wherein the layer structure further comprises at least one auxiliary resin layer.

40. 34. The method of forming a capacitor of claim 33, wherein the layer structure further comprises at least one serpentine prepreg.

41. 41. The method of forming a capacitor of claim 40, wherein the at least one serpentine prepreg is at a periphery of the pocket.

42. 41. The method of forming a capacitor of claim 40, wherein the serpentine prepreg is an overloaded serpentine prepreg.

43. 34. The method of forming a capacitor of claim 33 further comprising forming an encapsulant and forming a hole through said encapsulant.

44. 44. The method of forming a capacitor of claim 43, wherein the hole extends through at least a portion of an anode lead, the anode lead being in electrical contact with the anode.

45. 45. The method of forming a capacitor of claim 44, wherein the anode lead is an anode wire.

46. 46. ​​The method of forming a capacitor of claim 45, further comprising forming a metallization in said hole, said metallization being in electrical contact with said anode lead.

47. an upper reinforcing sealant layer; a lower reinforcing sealant layer; an electronic element between the upper and lower reinforcing encapsulant layers; an inner reinforcing sealant layer disposed between the upper reinforcing sealant layer and the lower reinforcing sealant layer, the inner reinforcing sealant layer comprising a membrane; An electronic component comprising:

48. 48. The electronic component of claim 47, wherein the electronic element is selected from the group consisting of a capacitive element, a resistive element, a varistor element, an inductive element, a diode, a fuse, an overvoltage discharge element, a sensor, a switch, an electrostatic discharge suppression element, a semiconductor, or an integrated circuit.

49. The electronic component according to claim 47 , further comprising a resin that encapsulates at least a portion of the electronic element.

50. 48. The electronic component of claim 47, wherein the inner reinforcing encapsulant layer is planar.

51. 48. The electronic component of claim 47, wherein the inner reinforcing encapsulant layer is serpentine.

52. 48. The electronic component of claim 47, wherein the inner reinforcing encapsulant layer includes a cavity with the electronic element within the cavity.

53. 53. The electronic component of claim 52, further comprising an inner reinforcing encapsulant layer serpentine at least partially around the cavity.

54. 48. The electronic component of claim 47, further comprising at least one additional inner reinforcing encapsulant layer.

55. 48. The electronic component of claim 47, further comprising at least one additional upper reinforcing encapsulant layer or at least one additional lower reinforcing encapsulant layer.

56. 48. The electronic component of claim 47, further comprising at least one resin layer between the upper reinforcing encapsulant layer and the inner reinforcing encapsulant layer or between the lower reinforcing encapsulant layer and the inner reinforcing encapsulant layer.

57. The electronic element is a capacitive element, An anode; a dielectric on the anode; and a cathode on said dielectric.

58. 58. The electronic component of claim 57, further comprising at least one anode lead in electrical contact with the anode.

59. 60. The electronic component of claim 58, wherein the electrical contact is made to an anode node that contacts the anode lead.

60. 60. The electronic component of claim 58, wherein the anode lead is an anode wire.

61. 58. The electronic component of claim 57, further comprising a termination disposed on a surface of the electronic component, the termination being in electrical contact with an electronic element.

62. 62. The electronic component of claim 61, wherein the electrical contact comprises a metallized hole.

63. 63. The electronic component of claim 62, wherein the metallized holes are exposed on a surface of the electronic component.

64. 62. The electronic component of claim 61, wherein the termination is exposed through a surface of the encapsulant.

65. 65. The electronic component of claim 64, wherein the termination is on at least one surface of the encapsulant.

66. 48. The electronic component of claim 47, wherein at least one of the upper reinforcing encapsulant layer or the lower reinforcing encapsulant layer further comprises an inner metal layer.

67. 67. The electronic component of claim 66, wherein the interior metal layer is electrically connected to an external termination.

68. 48. The electronic component of claim 47, further comprising a surface metal layer on at least one of the upper reinforcement encapsulant layer or the lower reinforcement encapsulant layer.

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