Abstract: A compliant structure for an electronic device comprises a substrate (110) composed of a first material (111) and a compliant zone (120) within the substrate. A plurality of solder joints (280) are located between, and form a connection between, the substrate and the electronic device (290). The compliant zone reduces the degree of deformation experienced by the solder joints due to thermal mismatch loading between the substrate and the die during attachment of the die to the substrate (chip attach). This reduction in solder joint deformation reduces the likelihood that the solder joints will crack.

Abstract: A method for making a circuit plate includes: forming first holes in an insulating layer; forming a conductive layer on the insulating layer such that a portion of the conductive layer fills the first holes; grinding the conductive layer such that the portion of the conductive layer remains in the first holes to form a pattern of conductive traces; forming a dielectric protective layer that covers the insulating layer and the conductive traces; forming a pattern of second holes in the protective layer such that a portion of each of the conductive traces is accessible through a respective one of the second holes; and forming conductive bumps that are respectively connected to the conductive traces.

Abstract: A circuit board includes a substrate, an insulating layer, at least one protrusion, and a first circuit layer. The insulating layer is disposed on the substrate and has at least one protrusion-positioning region. At least a part of the protrusion is disposed on the protrusion-positioning region. The first circuit layer is disposed on the insulating layer and has at least one trace line extending onto the protrusion.

Abstract: A method of making a circuitized substrate assembly in which two or more subassemblies are aligned and bonded together. The bonding, preferably using lamination, results in effective electrical connections being formed between respective pairs of conductors of the subassemblies in such a manner that the metallurgies of the conductors, and those of an interim metallic solder paste, are effectively mixed and the flowable interim dielectric used between the mating subassemblies is forced to flow to engage and surround the conductor coupling, without adversely affecting the electrical connection formed.

Abstract: A method of manufacturing a solid-state imaging device. An end portion on the aperture side of each of the plurality of wirings forms an internal terminal portion and an end portion on the outer peripheral side of each of the plurality of wirings forms an external terminal portion, the internal terminal portion of the wiring being connected electrically with an electrode of the imaging element. The wirings are made of thin metal plate leads, the base is made up of a resin molded member in which the thin metal plate leads are embedded, and at least a part of a side edge face of the thin metal plate leads is embedded in the base. The rigidity of the base is enhanced by the thin metal plate leads, thus reducing a curl and a warp of the base.

Abstract: A method relating to a multi-functional, structural circuit, referred to as a structural circuit, is disclosed. The method can include thermoforming a liquid crystal polymer (LCP) circuit with a structural element (215). At least one circuit component can be attached to the surface of the LCP circuit (220).

Abstract: A substrate for a semiconductor package and a method of manufacturing the same are provided. More particularly, the substrate for the semiconductor package and the method for manufacturing the same include metal pieces, with some of the metal pieces having one end embedded within an insulating layer for insulating an external connection electrode of the substrate and the other end embedded within a solder. The substrate for the semiconductor package has the effects of preventing or retarding a connection failure in a solder connection portion by blocking or retarding the propagation of a crack, and allowing a solder to be easily permeated under the metal pieces and formed at a desired position.

Abstract: A method of manufacturing a, in order to accommodate the words range and to clarify the multilayer wiring board, grooves for forming a wiring circuit and via holes are formed in an insulating substrate formed from a thermoplastic resin composition comprising a polyarylketone resin with a crystalline melting peak temperature of at least 260° C. and an amorphous polyetherimide resin as the primary constituents, a metallic foil is embedded within the grooves so that the surface of the foil protrudes to the surface of the insulating substrate, and a conductive material formed by curing a conductive paste is used for filling the via holes.

Abstract: An optical pickup apparatus is described which includes a movable unit with an objective lens, a focus servo coil for moving the moveable unit containing the objective lens in the optical-axis direction, and tracking servo coils for moving the moveable unit containing the objective lens in the horizontal directions, and a liquid crystal element disposed for correcting the refractive index. Springs simultaneously provide support for the moveable unit and feed power to the liquid crystal element, the focus servo coil, and the tracking servo coils. A method for making said optical pickup apparatus is described. Two sheets, each having four springs extending across an opening formed by punching, are disposed parallel to each other at a predetermined distance. On these sheets, a fixed unit and a movable unit are formed by insert-molding. Excess portions of the metal sheets are removed, and a through-hole is formed so that connected portions of the wirings, lying side by side, are disconnected.

Abstract: A method of manufacturing an electrical-resistance heating element includes forming sintered ceramics or calcined ceramics, forming an electrode on the sintered ceramics or the calcined ceramics, and forming a ceramic base material having mainly a high melting point metal on the electrode embedded therein, thereby forming a heating element with built-in electrode.

Abstract: The present invention includes methods for making liquid crystalline polymer (LCP) interconnect structures using a high temperature and low temperature single sided liquid crystalline polymer LCP where both the high and low temperature LCP are drilled to form a z-axis connection. The single sided conductive layer is a bus layer to form z axis conductive stud within the high and low temperature LCP, followed by a metallic capping layer of the stud that serves as the bonding metal between the conductive interconnects to form the z-axis connection. High and low temperature LCP layers are etched or built up to form circuit patterns and subsequently bonded together to form final multilayer circuit pattern where the low temperature LCP melts to form both dielectric to dielectric bond to high temperature LCP circuit layer, and dielectric to conductive bond, whereas metal to metal bonding occurs with high temperature metal capping layer bonding to conductive metal layer.

Abstract: In the manufacture of an electric heater, means (24, 26) is provided for feeding and guiding a ribbon heating element (14) progressively into overlying edgewise relationship with a base (2). Means (6, 8) is provided for supporting the base (2) and for effecting relative motion between the base (2) and the feeding and guiding means (24, 26), such that motion of the base (2) is synchronised with feeding of the element (14) as it is fed and guided into the relationship with the base (2), to urge the heating element (14) towards the base (2) and cause an edge portion (22) of the heating element (14) to become embedded in the base (2).

Abstract: The present invention provides a method of fabricating a crystal oscillator with pedestal for surface mounting, which is provided on a base surface of a crystal oscillator from which a pair of lead wires extends and which is formed by injection molding using a mold with a liquid-crystal polymer as raw material; wherein protrusions that follow the shape of said mold are provided on at least a corner around the outer periphery of the surface of the oscillator pedestal facing said base surface of said crystal oscillator; a non-defective product is assumed to be one in which the upper surface of each of said protrusions is a flat surface, but a defective product is assumed to be one in which the flat surface of said protrusion is ridged; and only a non-defective product is mounted onto the base surface of the crystal oscillator. This makes it possible to provide a method of fabricating a crystal oscillator by which reliability is increased while the strength of the oscillator pedestal is maintained.

Abstract: A surface acoustic wave device which occupies a small mounting area and has a low profile, yet having an improved reliability, and can be made available at low cost. The surface acoustic wave device comprises a piezoelectric substrate, a function region formed of comb-like electrodes for exciting surface acoustic wave provided on a main surface of the piezoelectric substrate, a space formation member covering the function region, a plurality of bump electrodes provided on a main surface of the piezoelectric substrate and a terminal electrode provided opposed to the main surface of piezoelectric substrate. The bump electrode and the terminal electrode are having a direct electrical connection, and a space between piezoelectric substrate and terminal electrode is filled with resin.

Abstract: Processes for fabricating a multi-layer circuit assembly and a multi-layer circuit assembly fabricated by such processes are provided. The process includes (a) providing a substrate at least one area of which comprises a plurality of vias, these area(s) having a via density of 500 to 10,000 holes/square inch (75 to 1550 holes/square centimeter); (b) applying a dielectric coating onto all exposed surfaces of the substrate to form a conformal coating thereon; and (c) applying a layer of metal to all surfaces of the substrate. Additional processing steps such as circuitization may be included.

Abstract: A pre-casting multi-layer PCB process has steel plate mold engraved with circuitry and the epoxy coated on the mold for the epoxy to cover up a fiber glass substrate; conductive material coated on the epoxy to insert molding the former into the latter to form recessed circuitry; then baked and solidified, sandblasted to remove film for the conductive material to become conducted circuitry; the lamination made by layer for achieving even thinner PBC circuitry while maintaining sufficient structural strength.

Abstract: The present invention provides a composite magnetic body containing metallic magnetic powder and thermosetting resin and having a packing ratio of the metallic magnetic powder of 65 vol % to 90 vol % and an electrical resistivity of at least 104 ?·cm. When a coil is embedded in this composite magnetic body, a miniature magnetic element can be obtained that has a high inductance value and is excellent in DC bias characteristics.

Abstract: A substrate for mounting an electronic component, includes a baseplate having a main surface formed with or without a recess. A ceramic substrate is provided on the main surface of the baseplate and has a smaller size than the baseplate. A metal layer is provided to cover both of the baseplate and the ceramic substrate. The metal layer has a surface remote from the baseplate and the ceramic substrate is made flat, the baseplate is made of a metal-ceramic composite of a metallic material and a ceramic material, and the metallic material in the composite and the metal layer have different compositions. Thus, an integral ceramic circuit board, which is resistant to repeated thermal stress and is superior in reliability can be realized.

Abstract: A method for producing an ink jet head including, on a substrate, a piezoelectric element for discharging an ink from a discharge port, and an ink flow path communicating with the discharge port so as to correspond to the piezoelectric element, the method comprising in this order a step of providing, on the substrate, a mold material corresponding to the ink flow path, a step of providing a wall material of the ink flow path so as to cover the mold material, a step of eliminating a portion of the substrate corresponding to the piezoelectric element thereby forming a space in the substrate, and a step of eliminating the mold material thereby forming the ink flow path.

Abstract: A method for providing an encapsulated optoelectronic chip is provided. The optoelectronic chip is secured on a substrate. A translucent coating substance is then applied on said optoelectronic chip and the translucent coating substance is then polished away to enable an optical coupling.

Abstract: An electrical connection terminal of an embedded chip and a method for fabricating the same are disclosed. An insulating layer is provided on a circuit board integrated with a chip and has a plurality of first openings for exposing a conductive pad of the chip. A first metal layer is formed on the conductive pad, and a conductive layer if formed on surfaces of the first metal layer, the insulating layer and the first openings. A patterned resist layer is formed on the conductive layer and has a plurality of second openings for exposing a part of the conductive layer corresponding to the condictive pad of the chip. A second metal layer is formed on the exposed part of the conductive layer by an electroplating process. Thus, the fabrication of conductive structure of the conductive pad of the ship and build-up of conductive circuits on the circuit board are integrated simultaneously.

Abstract: A process is described in which surfaces of foamed plastics are provided with electrical conductor tracks, with the aid of selectively ablating processes. The process permits low-cost production of moldings from plastic with conductor tracks integrated on the surface. The products of the process may be used in the electrical and electronics industries, for example.

Abstract: A process for manufacturing an inductive component intended to be installed on a printed circuit involves initially winding an electrically conductive wire to form a winding without using a former end connecting the opposed ends of the winding to inner ends of connecting terminals. The body formed of a block of an insulating material is then over-moulded onto the coil and onto the inner ends of the connecting terminals with the body including a central opening that passes through the body along the axis of the coil. Finally, a core made of ferrite is placed on the body such that the core surrounds the body in a center plane containing the axis of the coil with a center core element passing through the opening in the body.

Abstract: An electronic module and method that enable circuitry required by one form of the module (e.g., a developmental unit) to be omitted in a second form of the module (e.g., a production unit), without necessitating additional changes in the module. The electronic module includes a motherboard, a multichip module (MCM) mounted to the motherboard, and a circuit unit connected to the MCM. The circuit unit comprises a flexible substrate, instrumentation circuitry mounted on the flexible substrate, and a connector coupled to the flexible substrate. The flexible substrate has signal lines that electrically communicate with the MCM, the instrumentation circuitry, and the connector. A portion of the flexible substrate is located between the MCM and the motherboard and permits electrical communication therebetween. The instrumentation circuitry does not occupy space on the motherboard.

Abstract: Reel-to-reel manufacturing methods and systems are disclosed herein. In general, one or more plastic parts (e.g., plastic substrate) can be transported on a carrier for manufacturing of a final product based initially on the part or substrate. A reel-to-reel mechanism is provided comprising one or more reels associated with the carrier, such that the part can be spooled and unspoiled upon the one or more of the reels prior and subsequent to a performance of a manufacturing operation upon the part for the purpose of creating an electronic circuit. A plurality of manufacturing operations can then be subsequently upon the part utilizing the reel-to-reel mechanism to create a final electronic system based upon the part initially subject to the manufacturing operations.

Abstract: A method of manufacturing a liquid discharge head provided with a liquid flow path communicating with a liquid discharge port on a substrate has a step of forming a first electrically conductive layer on the substrate, a step of forming a molding member into the pattern shape of the flow path on the substrate, a step of forming a second electrically conductive layer on the molding member so as not to contact with the first electrically conductive layer, a step of forming a metal film by a plating process around the molding member by the utilization of the first electrically conductive layer and the second electrically conductive layer, and a step of removing the molding member and forming the flow path.

Abstract: A compression function layer 60 is provided on at least one board surface. The compression function layer 60 adds a function of being compressed by receiving pressure in the direction of the board thickness to the resin board 10 which includes this layer. Thereby a sufficient pressure is applied to conductors 14.

Abstract: A mechanical limiter switch device, having: a housing with a slot passing at least partially therearound, the slot forming a plurality of teeth in a side of the housing; a plunger movable within the housing; a biasing mechanism configured to urge the plunger in a proximal direction within the housing; a contact member extending through the slot in the side of the housing, the contact member being configured to advance past at least one of each of the plurality of teeth in the slot each time the plunger is moved back and forth within the housing. The contact member may perform a switching function.

Abstract: Method and apparatus for controlling an injection molding machine having a first surface and a second surface includes a piezo-ceramic sensor configured to be disposed between the first surface and a second surface. The piezo-ceramic sensor is configured to sense a force between the first surface and the second surface, and to generate corresponding sense signals. Transmission structure is coupled to the piezo-ceramic sensor and is configured to carry the sense signals. Preferably, a piezo-ceramic actuator is also disposed between the first surface and a second surface, and is configured to provide an expansive force between the first surface and a second surface in accordance with the sense signals.

Abstract: Methods of making certain piezoelectric films are disclosed. For example, a certain method of making piezoelectric films consistent with certain embodiments of the invention can include the steps of obtaining a piezoelectric material, reducing said piezoelectric material to particles, contacting said particles with a flexible matrix material, and applying said matrix material to one or more surfaces of a member.

Abstract: A sheet-like thermally conductive resin composition containing 70 to 95 wt. % inorganic filler and 5 to 30 wt. % thermosetting resin composition, a lead frame as a wiring pattern, and an electrically conductive heat sink with a metal pole placed therein are superposed, heated and compressed, and thus are combined to form one body. Consequently, a thermally conductive circuit board with a flat surface is obtained in which a grounding pattern is grounded to the heat sink inside the insulating layer. Thus, the grounding pattern and the heat sink can be connected electrically with each other in an arbitrary position inside the insulating layer of the thermally conductive circuit board. Accordingly, there are provided a thermally conductive circuit board with high heat dissipation, high conductivity and high ground-connection reliability, a method of manufacturing the same, and a power module allowing its size to be reduced and its density to be increased.

Abstract: Methods of manufacturing a printed board assembly. In one embodiment, a substrate is coated with an electrically conducting material; electrical components are mounted on some areas of the substrate; non-conducting material is disposed in areas between the electrical components; the substrate, electrical components and non-conducting material are sandwiched between two sheets of resin coated conducting foil, wherein the resin on the foils faces the substrate and buries the electrical components; circuit patterns are etched in the exposed surfaces of the resin coated conducting foils; and, electrical connections are established between at least one of the resin coated conducting foils and the electronic components.

Abstract: A method for forming a medium having a substrate is formed have a patterned surface with a channel pattern and a transponder having a memory is provided in the channel pattern. A conductive material is deposited in the channel pattern with the conductive material operatively associated with the transponder.

Abstract: A method of manufacturing a semiconductor mounting board includes providing a base member and linear conductive members formed of metallic wires. The conductive members are constructed so that they extend linearly between a semiconductor element-mounting face and a circuit board-mounting face of a base member, and are integrally molded within the base member. For this purpose, a resin material for forming the base member is injected into a mold wherein the conductive members are linearly arranged beforehand.

Abstract: A method and apparatus are disclosed for controlling temperature of a plant comprising plural temperature control zones, wherein an effective control parameter for a first zone for which a signal representing measured temperature is available is produced according to an algorithm relating measured temperature, a desired temperature and a control parameter associated with a device affecting temperature in the first temperature control zone, the effective control parameter is summed with an offset value representing a proportional offset of the effective control parameter of a second temperature control zone relative to the effective control parameter of the first temperature control zone and the result is applied to control a device affecting temperature in the second temperature control zone.

Abstract: A method of assembling a power distribution apparatus including a plurality of conductive circuit plates, each conductive plate including a plurality of contact pads that are interconnected by removable connecting links. The method includes selectively removing a portion of the connecting links on each conductive circuit plate to form discrete circuits on the conductive plates, stacking the conductive plates, mounting contact pins to selected contact pads, and heating the stacked plates and the mounted contact pins, thereby reflowing the conductive circuit plates and the pins to create solder joints therebetween.

Abstract: A method of manufacturing a non-reciprocal component including a casing having an input/output terminal and a ground terminal formed therein, a ferrite plate, a line conductor, and a magnet disposed in the casing, and an upper yoke and a lower yoke provided at the top face and the bottom face of the casing, respectively. In the non-reciprocal component, the casing is insert-molded with the lower yoke so that a portion of the casing penetrates through the lower yoke. A side of the component is defined partly by the lower yoke and partly by the penetrating portion of the casing. An input/output terminal and a ground terminal in the casing are defined by respective portions of a molded hoop material.

Abstract: The present invention provides a method for manufacturing an ink jet recording head utilizing ink bubbling by heating of an exothermic resistor to thereby eject ink and a method manufacturing the same, including the steps of: preparing a substrate provided with the exothermic resistor; applying such first resin on the substrate as to provide a first mold shape for forming the nozzle channel and the movable member; forming the first mold shape using the first resin; applying, on the substrate, second resin over the first mold shape for forming the nozzle channel and the movable member; and removing the first mold shape. By this method, the movable member is formed in the nozzle channel between the ink inlet and the exothermic resistor to thereby provide a high-density, high-accuracy ink jet recording head which can improve a frequency response while maintaining proper discharge performance.

Abstract: A resin filled board is manufactured by forming roughened surfaces on a conductive layer in a throughhole before it is filled with a resin, forming smooth surfaces on conductive layers on the top and bottom of the board, printing the resin using a mask having an opening at a position corresponding to the throughhole to selectively fill the resin in the throughhole, and curing the resin. In this way, the surface of the conductive layer around the throughhole is smoothed, so that hardly any of the resin remains on the surfaces near the throughhole when the surfaces of the board is mechanically polished after the resin is cured. Also, the filling resin will not fall down into the throughhole.

Abstract: An housing of a meter unit is inserted from above into a meter unit support hole which is provided in the rear handle cover. Engagement claws of the housing are engaged with claw receiving portions of the rear handle cover, thereby prevent the housing from coming out. Male connector is provided beforehand in the rear handle cover, and inserting the housing of the meter unit into the meter unit support hole causes the female connector of the housing to be automatically connected to the male connector, thus completing the wiring work of the meter unit. The wiring work on the meter unit supported on the rear handle cover of the motorcycle can therefore be performed easily and reliably.

Abstract: A method of manufacturing a circuit board by forming a circuit pattern in a short process and capable of performing pattern transfer with stability. The manufacturing method includes a step of superposing on a carrier a resist layer in which a circuit pattern is formed and which is formed of a conductor or an insulator, a step of filling the circuit pattern with an electroconductive material, a step of removing the resist layer from the carrier, and a step of transferring the electroconductive material filled in the circuit pattern into an electrical insulating material.

Abstract: A method for manufacturing wired circuit board that enables a wired circuit board of high quality to be manufactured without changing in dimension of the wired circuit board substantially. In this method, the wired circuit board is wound in layers in the winding process in such a manner that after an uncured thermosetting resin layer is formed on the wired circuit board in the resin layer forming process, a right-side spacer and a left-side spacer are disposed on the already wound wired circuit board at both widthwise ends thereof and also an upper spacer is disposed on the right-side spacer and the left-side spacer so as to cover a widthwise area of the wired circuit board, so that the right-side spacer, the left-side spacer and the upper spacer are positioned between the layers of the wired circuit board when wound. Thereafter, the wired circuit board wound in the rolled state is heated as it is, to cure the uncured thermosetting resin layer in the curing process.

Abstract: A structural frame (12) for dissipating heat from an electronic device (10) is provided. The structural frame (12), to which an electronic circuit board (14) containing a heat generating electronic component (16) is mounted, is injection molded from a thermally conductive, net-shape moldable polymer composition. The electronic component (16) that is within the device (10) is in thermal communication with the structural frame (12), so that the heat generated within the device (10) is transferred to the frame (14) and dissipated from the heat-generating device (10). An outer case (22) may be mounted to the frame (12) to finish the device (10) or the frame (12) may serve as all or a part of the outer device case (22) as well. In addition, the structural frame (12) has characteristics that may be engineered and used to shield the device (10) from electromagnetic interference.

Abstract: A device and method of unitarily forming an electrically shielded panel for use in electromagnetically sealing an opening defined in an electronic enclosure. The unitary electrically shielded panel is formed of an electrically non-conductive rigid thermoplastic panel part and a substantially planar, electrically conductive elastomeric gasket bonded together to form the unitary panel in a single tool during a single injection-molding operation.

Abstract: In a method of manufacturing a thermally conductive circuit board with high heat dissipation, high conductivity and high ground-connection, a sheet-like thermally conductive resin composition containing 70 to 95 wt. % inorganic filler and 5 to 30 wt. % thermosetting resin composition, a lead frame as a wiring pattern, and an electrically conductive heat sink with a metal pole placed therein are superposed, heated and compressed, and thus are combined to form one body. Consequently, a thermally conductive circuit board with a flat surface is obtained in which a grounding pattern is grounded to the heat sink inside the insulating layer. Thus, the grounding pattern and the heat sink can be connected electrically with each other in an arbitrary position inside the insulating layer of the thermally conductive circuit board.

Abstract: A method for making electrical interposers which includes the use of a stencil which is thicker than designated lower contact pads and which defines a stencil passage corresponding to each lower contact pad of each interposer. The stencil is attached to a bottom surface of an insulative layer and a conductive elastomeric material is applied to the stencil, so that the stencil passages are filled with said conductive elastomeric material. When this material has been adequately placed within the stencil passages the stencil is removed thus leaving each lower conductive pad with an attached conductive elastomeric pad.

Abstract: A method and structure to form surface plating metallization on a substrate. Two layers of tape are applied to the surface of the substrate. A first path is cut through both layers of tape exposing the substrate surface. The first path connects at least one conductive via on the top surface of the substrate. A second path is cut through the second layer of tape exposing the first layer of tape. The second path is routed from the first path to an edge of the substrate A seed layer is deposited over the surface of the second layer of tape thereby creating a seeded plating path in the first path and a sacrificial seeded conduction path in the second path. Connecting the sacrificial seeded conduction path to a plating potential at the edge of the substrate creates a plated path on the surface of the substrate. The sacrificial path is removed when the tape is removed.

Abstract: A metallic thin film 15 is formed on a mold 11 having protrusions 12 complementary in shape to a conductor pattern to be formed; a substrate 17 having a transfer layer 16 of adherent (or adhesive) material applied to one side surface thereof is provided; and the transfer layer 16 side of the substrate is brought into intimate contact with the metallic thin film 15 laid over the protrusions 12, followed by pulling the transfer layer apart from the mold so as to transfer the metallic thin film 15 covering the protrusions 12 onto the transfer layer 16 to thereby form the conductor pattern 18 on the transfer layer 16. The metal film may include cooper and a weak adherence layer 13 which may be gold.

Abstract: A method of making an interactive information package, including an interactive information closure including a radio frequency identification device, contemplates that a microelectronics assembly be provided, and positioned on an associated substrate for positioning adjacent an inside surface of the top wall portion of the closure of the package. In one embodiment, the mounting substrate is provided in the form of a disc-shaped sealing liner for the closure. In an alternate embodiment, the mounting substrate is laminated to an associated sealing liner, with the substrate, and microelectronics assembly positioned thereon, inserted together with the sealing liner into the associated molded closure.

Abstract: The present invention relates to a method for fabricating a wiring substrate by forming an insulating film on a metal base having openings on the metal base at positions corresponding to metal bumps to be formed later; forming at least one layer of wiring on the base made of a metal through the insulating film, the layer of wiring having a wring film formed thereon by electroplating; and selectively etching the base. The insulating film can be a liquid photosensitive polyamide, the wiring layer can be copper and the wiring film can be a conductive layer selected from the group consisting of Ni-P and Ni. In the present invention, the wiring layer can be formed through the insulating film in contact with the metal base at the openings in the insulating film and in contact with the insulating film where there are no openings in the insulating film.