JP6155545B2 - Circuit board with external connection conductor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a circuit board with an external connection conductor that is integrated with an external connection conductor that is intended to be connected to an external sensor or actuator, and a method for manufacturing the circuit board.

In recent years, high performance has been advanced in the control of internal combustion engines such as automobile engines and general industrial equipment, and various sensors and actuators have been used. The sensors and actuators and circuit boards for controlling them have been used. Improvement of reliability in connection is regarded as important, and various circuit boards to which external connection conductors for connection to the outside such as input lines and output lines are connected have been proposed.
For example, Patent Document 1 discloses a circuit board configured to receive a sensor signal and generate sensor characteristics in accordance with the received sensor signal, a container that accommodates the circuit board therein, and a signal from the sensor. There is disclosed a sensor adapter circuit housing assembly comprising an input line configured to receive the signal and a connector of a predetermined shape coupled to the end of the input line.

  However, in the conventional sensor adapter circuit housing assembly as disclosed in Patent Document 1, a connector having a complicated shape such as a crimp terminal is used as an external connection conductor for connecting an input line or an output line to a circuit board. Therefore, after the signal line to which the connector is connected is housed in the mold, the resin constituting the housing is filled in the cavity of the mold, and after integration with the housing by so-called insert molding, It was necessary to make a connection, and the manufacturing process was complicated and difficult to automate.

In particular, external sensors that are used in high temperature environments of 200 ° C or higher, such as temperature sensors and exhaust sensors, and heaters and glow plugs that generate heat of several hundred ° C or higher are used to input and output between circuit boards. For the connecting conductor, for example, a heat-resistant conductor made of a stranded wire made of a highly conductive annealed copper wire and a highly heat-resistant stainless wire, or nickel plating for improving the heat resistance of a highly conductive copper wire, etc. Heat-resistant conductors, etc., which are coated with heat-resistant conductors, etc., covered with a heat-resistant insulator such as fluorine rubber, silicone rubber, polyimide, crosslinked polyethylene, crosslinked vinyl chloride, glass fiber are used. .
However, such heat-resistant conductive wires have poor solder wettability and are difficult to solder directly to the circuit board, and conventionally have been forced to be connected to the circuit board via connectors such as crimp terminals.
For this reason, in recent years, there is a high demand for further miniaturization of circuit boards and circuit modules. However, when connecting circuit boards to devices that are used in high temperature environments or generate heat, There has been a limit to the miniaturization of circuit boards with conductive wires that use conductive wires and necessarily require connectors such as crimp terminals.
In addition, if the adhesion between the crimp terminal and the heat-resistant conductor is insufficient, the contact resistance increases, which may cause a decrease in detection accuracy of the sensor and a decrease in control accuracy of the actuator.

On the other hand, Patent Document 2 discloses an FPC and a metal terminal that can obtain a good bond between a flexible printed wiring board (FPC) in which a conductor wiring is formed on a flexible resin film and a metal terminal. As a connecting method, the FPC conductor wiring surface is overlapped with the tab to be connected, and the metal foil is interposed on the surface opposite to the FPC conductor wiring, and sandwiched between the anvil and the horn of the ultrasonic welding machine. A method for ultrasonic fusion is disclosed.
However, in order to directly connect the heat-resistant lead wire to the electrode part of the circuit board by ultrasonic welding, the ultrasonic vibration is applied while pressing the electric wire and the electrode part with the circuit board sandwiched between them. Ultrasonic vibration was absorbed by an insulating substrate such as a glass epoxy resin used for a circuit board, and it was difficult to perform ultrasonic fusion.

Therefore, as shown in FIG. 10, a heat-resistant conductor 600 having poor solder wettability is used as an external connection conductor for connecting the circuit board 1z in which a predetermined circuit is formed on the insulating substrate 100 to the outside. When the heat resistant conductor 60z covered with 610 is used, the land 200z formed on the surface of the circuit board 1z and the heat resistant conductor 60z are connected with a metal material having good solder wettability. In order to directly join the metal piece terminal portion 50z and the end portion 601 of the heat-resistant conductor 600 using a joining means such as ultrasonic welding or resistance welding through the soldered metal piece terminal portion 50z. to, by providing a groove 101z, with parts cut away, of the insulating substrate 100z such that there is an insulating substrate 100z on the direction of the welding axis perpendicular to the junction P _WLD, ultrasonic The welding jigs W ₁ and W ₂ such as the horn and anvil of the wave welding machine and the pair of electrodes of the resistance welding machine do not sandwich the insulating substrate 100z, and the terminal portion 601 and the metal piece terminal of the heat resistant conductor 600 It is conceivable that the portion 50z is directly sandwiched so that ultrasonic welding can be performed or resistance welding can be performed.

On the other hand, as disclosed in Patent Document 3, in a general printed circuit board, a predetermined circuit pattern is formed by a copper foil or the like on the surface of an insulating substrate made of glass epoxy resin or the like. A land for establishing electrical connection by soldering or the like is formed.
Furthermore, when soldering various parts to the lands, the parts other than the lands are formed by applying and curing an insulating resin or the like in order to prevent the solder from adhering to the parts other than the contacts and short-circuiting. It is covered with the solder resist, and the land is exposed from the opening provided in the solder resist.
The solder resist also functions as a protective layer that covers and protects portions other than the land.

However, as shown in FIG. 10, when soldering is performed by forming a solder layer 40z so as to entirely cover the portion where the land 200z exposed from the opening 301z of the solder resist 30z and the metal terminal portion 50z are in contact with each other. 11A and 11B, the metal piece terminal portion 50 soldered to the land of the circuit board 200 is welded to a welding jig W ₁ , W ₁ such as a welding horn tip and an anvil, a resistance welding electrode, or the like. _The stress caused by the load and vibration generated when sandwiched from above and below by ₂ , ultrasonic vibration generated during ultrasonic welding, electrical vibration generated during resistance welding, thermal vibration, etc. is transmitted to the land 200 z via the solder 40 z. 11C and 11D, the land 200z is peeled off from the surface of the insulating substrate 100, and the land 200z is damaged and electrically That there is a fear of lowering significantly the connection reliability has been found.

  Therefore, in view of such circumstances, the present invention provides a circuit board with an external connection conductor that includes a heat-resistant conductive wire that is difficult to be directly connected to the circuit board. It aims at providing the manufacturing method.

According to the first aspect of the present invention (1, 1a, 1b, 1c, 1d, 1e), an insulating substrate (100) having a groove (101) in which a part of the outer peripheral edge is notched inward, and the groove ( 101) a conductive layer (20) having a metal piece mounting land (200) provided on the peripheral surface of the metal piece and a wiring portion (201) connected to at least a part of the metal piece mounting land (200);
A substantially flat metal piece (50, 50c) that is soldered and fixed to the metal piece mounting land (200) across the groove (101),
A solder resist layer (30, 30b, 30c) provided between the metal piece (50, 50c) and the conductor layer (20);
External connection conductors (60, 600d, 600e) and external connection conductors (60, 610d, 611d, 610e) comprising external conductors (610, 610d, 611d, 610e) covering the conductors (600, 600d, 600e). 60d, 60e)
The external connection conductor (60, 60d, 60e) includes, as the conductor (600, 600d, 600e), a heat-resistant conductor having high heat resistance of 150 ° C. or more, and the conductor (600, 600d, 600e), the conductor terminal portions (601, 601d, 601e) exposed from the outer conductor insulator ( 610, 610d, 611d, 610e ) and the metal pieces (50, 50c) are connected to the groove portion ( 101) a circuit board with an external connection conductor joined and electrically connected to the outside,
The metal piece mounting lands ( 200 ) are on both sides of the land (200b) connected to the wiring part (201) on the opposite side of the opening of the groove part (101) and the groove part (101). Divided into the land (202) to be placed,
The solder resist layer (30, 30b, 30c)
A part of each divided metal piece mounting land (200b, 202) is exposed, and a land part exposing opening (301, 301b, 301c) which is an independent opening not communicating with the groove (101);
The solder resist layer (30, 30b, 30c)
A part of each divided metal piece mounting land (200b, 202) is exposed, and a land part exposing opening (301, 301b, 301c) which is an independent opening not communicating with the groove (101);
The metal piece mounting lands (200b, 202) are covered so as to surround the land portion exposure openings (301, 301b, 301c) and cover a part of the metal piece mounting lands (200b, 202). A partially shielding land partial shielding portion (302, 302b, 302c),
The metal piece mounting land and (200b, 202) the metal strip and (50,50C) comprises an upper Kira command portion exposure opening portion (301,301b, 301c) solder layer provided inside the (40, 40b, 40c),
The conductor terminal portions (601, 601d, 601e) are inserted into the groove portion (101), and in the space surrounded by the metal pieces (50, 50c) and the insulating substrate (100), It is characterized by being joined to the pieces (50, 50c) by welding.

In the invention of claim 2 (1, 1a, 1b, 1c, 1d, 1e), the external connection conductor (60, 60d, 60e) is used as the external conductor insulator (610, 610d, 611d, 610e) , A heat-resistant insulator having high heat resistance of 150 ° C. or higher is provided .

In the invention (1d) of claim 3, the external connection conductor includes a substantially flat conductor foil (600d) as the conductor , and the flexible insulator has flexibility as the external conductor insulator. It is a flexible wiring board (60d) provided with a conductive insulator (610d, 611d).

In the invention (1e) of claim 4, the external connection conductor (60e) includes a connector (610e) fitted to the other party as the external conductor insulator, and the connector (610e) as the conductor. Is formed in a conductor terminal portion (601e), one end of which is exposed from the connector (610e) and joined to the metal piece (50, 50c), and the other end is located inside the connector (610e). The metal piece terminal (600e) which comprises the connector terminal part (602e) connected to this is comprised.

  In the invention of claim 5 (1, 1a, 1b, 1c, 1d, 1e), the heat-resistant conductor (600, 600d, 600e) is a heat-resistant wire using a tinned or nickel-plated annealed copper wire as a stranded wire. Conductive wire (600), heat-resistant conductor wire (600) using a nickel-plated annealed copper wire and stainless wire as a stranded wire, heat-resistant conductor wire (600) using an aluminum wire as a stranded wire, copper Heat-resistant conductor foil (600d) with tin or nickel plating on foil, heat-resistant conductor plate (600e) with tin or nickel plating on copper plate or copper alloy plate, tin or nickel plating on stainless steel plate The heat-resistant conductor plate (600e) which has been subjected to the above.

In the invention of claim 6 (1, 1a, 1b, 1c, 1d), the insulator for external conductor ( 610, 610d, 611d ) is made of fluoro rubber, fluoro resin, silicone rubber, silicone resin, polyimide, polyamide, cross-linking. It consists of polyethylene, cross-linked vinyl chloride, or glass fiber.

  In the invention (1e) of claim 7, the outer conductor insulator (610e) is made of PBT (polypropylene terephthalate) resin, PPS (polyphenylene sulfide) resin, PEEK (polyether ether ketone) resin, fluorine resin, polyamide resin. Consisting of either.

  In the invention of claim 8 (1, 1a, 1b, 1c, 1d, 1e), the metal material constituting the metal piece (50, 50c) is copper, copper alloy, nickel, nickel alloy (Ni / SUS / Ni). Clad steel), or steel material plated with nickel, copper, palladium, silver, tin, platinum, or gold.

In the invention of claim 9 (1, 1a, 1b, 1c, 1d, 1e), the insulating substrate (100) is an insulating resin substrate selected from polyimide, polyamideimide, aramid, and glass epoxy resin. The solder resist layer (30) is made of an insulating resin material containing a photo-curing resin.

In the invention of claim 10 (1, 1a, 1b, 1c, 1d, 1e), the insulating substrate (100) is a ceramic substrate of any one of alumina, titania, magnesia, and spinel, and the solder resist layer (30) is made of a heat-resistant glass material selected from either quartz glass or borosilicate glass.

According to an eleventh aspect of the present invention, there is provided a method for manufacturing a circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external conductor according to any one of the first to tenth aspects, wherein at least the wiring portion (201). ) And the metal piece mounting land (200, 200b, 202), a predetermined portion of the conductor layer (20) is soldered to the surface of the insulating substrate (100) on which the conductor layer (20) is formed. A solder resist forming step for forming a solder resist layer (30, 30b, 30c) for preventing the solder from being attached to the predetermined portion and protecting the predetermined portion by insulation, and the metal piece (50, 50c). ; and a mounting step of mounting the at the solder resist forming step, the solder resist layer (30, 30B, 0c) is, the metal piece mounting lands (200,200b, 202 Partial opening which allowed to expose a predetermined portion of (301,301b, 301c) and, partially shielding portion that covers a predetermined portion (302,302b, 302c) and provided with a, in the mounting step, the metal strip mounting land The solder layer (40, 40b, 40c) for fixing (200, 200b, 202) and the metal piece (50, 50c) is provided at a plurality of locations on the metal piece mounting land (200, 200b, 202). The metal piece mounting lands (200, 200b, 202) are exposed from the land portion exposure openings (301, 301b, 301c) and joined to the metal pieces (50, 50c) at positions where the metal piece mounting lands (200, 200b, 202) are divided at a plurality of locations. It is characterized by figure.

In the invention of claim 12, at least the terminal of the metal piece (50, 50c) and the external connection conductor ( 60, 60d, 60e ) using the groove (101) provided in the insulating substrate (100). A conductor joining step of joining the parts (601, 601d, 601e) so as to be sandwiched by the joining means.

  In invention of Claim 13, the joining means used at the said conductor joining process is either ultrasonic welding (USW) or resistance welding (RW).

According to the present invention, or load transmitted when sandwiched between the outer connecting conductor (60,60d, 60e) and said metal piece (50,50c) and the weld fixture _(W 1, W _2), welding The force applied to the metal piece mounting lands (200, 200b, 202) such as vibration generated sometimes is dispersed, and further, a part of the metal piece mounting lands (200, 200b, 202) is transferred to the solder resist layer ( 30) land portion shielding portions (302, 302b, 302c) are bridged so as to be bridged, and are thus firmly pressed by the land portion shielding portions (302, 302b, 302c), and the metal piece mounting lands (200) , 200b, 202), the circuit board (10, 10b, 10c) and the external connection conductor (60, 60d, 60e) can be opposed to each other. It is possible to realize a circuit board (1, 1a, 1b, 1c, 1d, 1e) that maintains high electrical connection reliability without causing land peeling during connection.

FIG. 2 is an exploded perspective view showing a main part of the circuit board according to the first embodiment of the present invention. FIG. 2C is a longitudinal sectional view taken along the line AA in FIG. 2C, showing an outline of the circuit board in the first embodiment of the present invention. Substrate longitudinal sectional view along BB in FIG. 2C Cross section along CC in FIG. 2B Cross-sectional view along DD in FIG. 2B It is a figure for demonstrating the effect of this invention with the outline | summary of the conductor joining process which is the principal part of the manufacturing process of the circuit board of FIG. 1, Comprising: Sectional drawing corresponding to the cross section shown to FIG. 2A Similarly, a cross-sectional view corresponding to the cross section shown in FIG. 2B Similarly, a cross-sectional view corresponding to the cross section shown in FIGS. 2C and 2D Sectional drawing which shows the outline | summary of resistance welding as a joining means applicable to this invention Similarly, a sectional view showing the outline of ultrasonic welding FIG. 1 is a perspective view schematically showing a control circuit module including the circuit board of FIG. Similarly, a perspective view showing the modified example 1a The principal part expanded perspective view which shows the outline | summary of the circuit board 1b in the 2nd Embodiment of this invention. The principal part expansion perspective view which shows the outline | summary of the circuit board 1c in the 3rd Embodiment of this invention. The perspective view which shows the outline | summary of the flexible wiring board used for the circuit board 1d in the 4th Embodiment of this invention. Sectional drawing which shows the outline | summary of the conductor joining process of the circuit board 1d in the embodiment Similarly, a cross-sectional view corresponding to FIG. 2A The perspective top view which shows the outline | summary of the circuit board 1e in the 5th Embodiment of this invention Sectional drawing which shows the outline | summary of the circuit board 1e in the embodiment Side view of circuit board 1e in the same embodiment An exploded perspective view showing an outline of a circuit board with a conductor having a structure not using the present invention in which a metal piece terminal portion is soldered to the entire surface of a land exposed from a solder resist as in a general mounting component shown as a comparative example Substrate longitudinal sectional view at the time of conducting wire bonding of a comparative example Cross-sectional view at the time of conducting wire bonding of a comparative example Cross-sectional view in the longitudinal direction of the substrate showing land peeling, which is a problem of the comparative example The cross-sectional view which shows land peeling which is a problem of a comparative example.

With reference to FIG. 1, FIG. 2A, FIG. 2B, FIG. 2C, and FIG. 2D, the outline | summary of the circuit board 1 with an external connection conductor in the 1st Embodiment of this invention is demonstrated. This embodiment shows a basic configuration of a second embodiment to be described later.
Moreover, the manufacturing method of the circuit board 1 of this invention is suitably demonstrated in every place with description of each embodiment.
The circuit board 1 with an external connection conductor in the present embodiment is constituted by a circuit board 10 and an external connection conductor 60 for connection to the outside.
Note that the functions of the control circuit and the like provided on the circuit board 10 are not particularly limited, and control with a controlled part such as control of a sensor exposed to a high temperature environment or control of an actuator accompanying a temperature rise of a heating element, etc. A high-temperature heat resistance of 150 ° C. or higher, and in some cases 200 ° C. or higher, and a heat-resistant conductor 600 with poor solder wettability covered with a heat-resistant insulator 610 is used as the external connection conductor 60. This is particularly effective when the terminal portion 601 of the heat-resistant conductor 600 is bonded to the metal piece 50 having good solder wettability and connected to the circuit board 10.
However, in the present invention, the external connection conductor 60 is not limited to the heat-resistant conductive wire having the above-described structure, and is a flexible printed wiring board (FPC) or a flexible flat type used in Embodiments 1d and 1e described later. A flat cable 60d such as a wiring board (FFC), a connector terminal 60e, or the like may be used.
Further, the circuit board 10 may not be provided with a circuit having a special control function, and may be used as a simple relay board.
The present invention provides, for example, a temperature sensor that measures engine coolant temperature, intake air temperature, combustion exhaust gas temperature, etc., and combustion exhaust gas such as an oxygen sensor, air-fuel ratio sensor, NOx sensor, ammonia sensor, PM sensor, etc. Detectors such as a gas sensor that detects the concentration of a specific component contained in the measurement gas are sensors such as sensors in the engine room, exhaust passages, etc. that are exposed to relatively high temperatures, glow plugs, heaters, etc. It can be suitably used for an actuator that generates heat.

The circuit board 10 includes an insulating substrate 100 having a groove portion 101 with a part of the outer peripheral edge cut out inward, and a metal piece mounting land 200 (hereinafter referred to as a “chip piece mounting land”) provided at least around the groove portion 101 on the surface thereof. And a conductor layer 20 including a wiring part 201 connected to the land 200 is formed and configured.
The external connection conductor 60 that makes electrical connection between the circuit board 10 and the outside is joined via a substantially flat metal piece 50 that is soldered and fixed to the land 200 across the groove portion 101.
The surface of the circuit board 10 covers a predetermined portion of the conductor layer 20 and is covered with a solder resist layer 30 (hereinafter referred to as a solder resist 30) that ensures insulation between conductors and protects the conductors . .
The solder resist 30 includes a land portion exposure opening 301 that exposes a part of the land 200 at a plurality of locations (hereinafter, referred to as a partial opening 301), and a land partial shield that covers the land 200 so as to straddle a part thereof. Part 302 (hereinafter, referred to as a partial shielding part 302). The solder layer 40 that fixes the land 200 and the metal piece 50 is exposed from the partial openings 301 provided at a plurality of locations of the land 200, and is joined to the metal piece 50 at a position where the land 200 is divided at the plurality of locations. Yes.

The solder resist 30 which is a main part of the present invention covers the wiring part 201 to ensure insulation between a plurality of conductors and to protect the conductor layer 20 (hereinafter referred to as a protection part 300). ), A land partial exposure opening 301 for exposing a part of the land 200 (hereinafter referred to as a partial opening 301), and a land partial shielding part 302 (hereinafter referred to as a part of the land 200). And a partial shielding portion 302).
In the present embodiment, the solder layer 40 includes a main solder layer 400 for ensuring conduction between the metal piece 50 and the land 200, and a plurality of divided solder layers 401 for reinforcing the bonding strength between the metal piece 50 and the land 200. And is composed of.
Further, as shown in FIGS. 1, 2A, and 2D, the metal piece 50 and the land 200 are firmly bonded to each other through solder layers 400 and 401 at a plurality of locations, and FIGS. As shown in FIG. 2C, a portion of the land 200 where the solder layers 400 and 401 are not formed is covered with a partial shielding portion 302 of the solder resist 300.
The solder resist 30 is provided so as to cover the surface of the insulating substrate 100, and can solder a predetermined portion of the conductor layer 20 exposed from the partial opening 301, and is formed by the partial shielding portion 302 and the protection portion 300. The predetermined portion covered is prevented from being soldered, and the predetermined portion of the conductor layer 20 is insulated and protected.

  The metal material with good solder wettability constituting the metal piece 50 is copper alloy such as copper, brass, phosphor bronze, nickel, nickel alloy (Ni / SUS / Ni clad steel), nickel, copper, palladium, silver, tin, It can be appropriately selected from any of steel materials plated with platinum and gold.

  In the present embodiment, the external connection conductor 60 includes a heat resistant conductor 600 having a high heat resistance of 150 ° C. or higher as a conductor and a heat resistant insulator 610 having a high heat resistance of 150 ° C. or higher as an outer conductor insulator. It is covered with.

  The heat-resistant conductor 600 is composed of a heat-resistant conductor wire in which an annealed copper wire subjected to tin plating or nickel plating is a stranded wire, a heat-resistant conductor wire in which an annealed copper wire and nickel wire subjected to nickel plating are stranded, aluminum Any of heat-resistant conductor wires in which the wires are stranded wires can be appropriately selected.

  As the heat-resistant insulator 610, any one of fluorine rubber, fluorine resin, silicone rubber, silicone resin, polyimide, crosslinked polyethylene, crosslinked vinyl chloride, and glass fiber can be selected as appropriate.

  In the case where the insulating substrate 100 is a printed circuit board including an insulating resin substrate selected from polyimide, polyamideimide, aramid, and glass epoxy resin, the solder resistor 30 includes a known insulating material including a photo-curing resin. A resin material can be used.

  When the insulating substrate 100 is a ceramic substrate made of any one of alumina, titania, magnesia, and spinel, the solder resist 30 may be a known heat resistant glass selected from either quartz glass or borosilicate glass. Materials can be used.

  When the insulating substrate 100 is a so-called printed substrate made of a glass epoxy resin or the like, the patterned conductor layer 20 is formed by a known method such as etching the copper foil attached to the surface thereof, and the conductor layer 20 A known insulating material containing a photo-curing resin is used for the solder resist 30 provided so as to cover the protective resist 300, and the protective resist 300, the partial opening 301, and the partial by a known method such as photolithography as a solder resist forming process. The shielding part 302 can be formed.

  When the insulating substrate 100 is a so-called ceramic substrate made of alumina or the like, the conductor layer 20 is formed by a known method such as screen printing using tungsten or the like, and the solder resist 30 is made of quartz glass or borosilicate glass. In the solder resist forming process, a cultivated land method such as thick film printing is used, and the conductor insulation protection part 300 and the partial opening part 301 exposing a part of the land 200 are used. In addition, a partial shielding portion 302 that covers a part of the land 200 can be formed.

As shown in FIGS. 2A and 2B, the circuit board 10 has predetermined circuit components 51 made of passive components such as resistors, capacitors, and inductors, and active components such as semiconductors and control ICs, as necessary. It is mounted by a known mounting process such as chip mounter or reflow.
The metal piece 50 is mounted and fixed so as to cover the groove portion 101 of the insulating substrate 10 together with other circuit components 51 through a known mounting process.
On the conductor layer 20, a general circuit component mounting land 210 (hereinafter referred to as a general land 210) for mounting the circuit component 51 as necessary is formed.
The electrode part 510 and the general land 210 of each circuit component 51 are electrically connected via the solder part 410.
The surface of the general land 210 for mounting the circuit component 51 is exposed from the general land opening 311 provided in the solder resist 300.
Further, the general land 210 can be formed at the same time as the conductor layer 20 described above, and the solder portion 410 can be formed at the same time as the hand layer 40 described above.
Further, the circuit board 10 is provided with via conductors 220 in the through holes 102 provided in the insulating substrate 100 so as to achieve conduction between the front and back of the insulating substrate 100, or a plurality of insulating substrates and conductor layers. A laminated multilayer substrate may be used.

In the circuit board 1 of the present invention, as shown in FIG. 3A, the external connection conductor 60 is inserted into the groove portion 101 in which a part of the edge of the circuit board 10 is notched inward, and is mounted on the circuit board 10. The metal piece 50 and the end portion 601 of the heat-resistant conductor 600 of the external connection conductor 60 are brought into contact with each other and, as shown in FIG. 3B, sandwiched from above and below by joining means W ₁ and W _{2 to} be described later. 50 and the end portion 601 of the heat-resistant wire conductor 600 are formed with a joint portion P _WLD for joining.
At this time, as shown in FIG. 3B, the metal pieces 50 and the terminal portions 601 of the heat-resistant conductor 600 are pressed from above and below by the joining means W ₁ and W ₂ from the up and down directions. The vibration in the direction of peeling the land 200 is transmitted to the land 200 via the solder layers 400 and 401. As shown in FIGS. 3A and 3C, the metal piece 50 and the land 200 are separated by the solder layer 40. The metal piece 50 and the land 200 are separated by the connected portion and the partial shielding portion 302 of the solder resist 30, and a part of the land 200 is covered by the partial shielding portion 302, thereby restricting the movement of the land 200. Therefore, the force applied to the land 200 is dispersed, and further, a part of the land 200 is covered so that the partial shielding portion 302 of the solder resist 30 is bridged. Therefore, the partial shielding portion 302 is firmly pressed down, and the vibration in the peeling direction of the land 200 is suppressed. The land 200 is not peeled off from the surface of the insulating substrate 100, and the electrical connection between the circuit board 10 and the external connection conductor 60 is achieved. Connection reliability can be improved.

With reference to FIG. 4A and FIG. 4B, the joining means and conductor joining process used for this invention are demonstrated.
In the configuration shown in FIG. 4A, a known resistance welder RW is used as the joining means.
The resistance welder RW uses the groove portion 101 in a state where the metal piece 50 and the end portion 601 of the heat resistant conductor 600 are in close contact with each other, and the pair of electrodes EL ₁ and EL ₂ from the vertical direction of the insulating substrate 100. For example, a large current of tens to tens of thousands of amperes is allowed to flow for a very short time of several milliseconds to several hundred milliseconds to generate Joule heat due to metal resistance. By melting the metal, the joint portion P _WLD made of an alloy between the metal piece 50 and the end portion 601 of the heat-resistant conductor 600 is formed.
At this time, the deviation of the pressing timing of the pair of electrodes EL ₁ and EL _2, the heat generated or load acts on the peeling direction of the lands 200, and the thermal expansion of the metal piece 50 at the time of generating the Joule heat by contraction Although the vibration may act as vibration in the peeling direction of the land 200, even if a load acts in the peeling direction of the land 200 due to a shift in the pressing timing of the pair of electrodes EL ₁ and EL ₂ , the land 200 Is covered with the partial shielding portion 302 of the solder resistor 300, is kept in close contact with the insulating substrate 100, and is further bonded to the metal piece 50 and the land 200 via the solder layer 40 in a state of being divided into a plurality of locations. Therefore, even if the metal piece 50 is thermally vibrated, the transmission to the land 200 is hindered and resonance is difficult to occur, and the separation of the land 200 is suppressed. Can.

On the other hand, in the configuration shown in FIG. 4B, a known ultrasonic welder USW is used as the joining means.
The ultrasonic welder USW converts the electrical signal into ultrasonic vibration by the transducer TRS and transmits it to the welding tip CHP via the ultrasonic horn HRN and uses the groove 101 to move the insulating substrate 100 in the vertical direction. Then, by pressing the welding tip CHP, a moderate pressure is applied to the metal piece 50 supported by the anvil ANV and the terminal portion 601 of the heat-resistant conductor 600 in parallel as shown by the bidirectional arrows in the figure. By oscillating, atomic diffusion is induced between the metal piece 50 and the end portion 601 of the heat-resistant conductor 600, causing bonding at the metal atom level to form the junction P _WLD .
At this time, as described above, since the joint between the metal piece 50 and the land 200 is soldered in a state of being divided into a plurality of locations, it is difficult to cause resonance even if ultrasonic vibration is transmitted to the land 200. Even if a load in the vertical direction acts in the peeling direction of the land 200 due to the timing deviation of the pressure between the ultrasonic chip CHP and the anvil ANV, the partial shielding portion 302 can suppress the peeling of the land 200.

As described above, the circuit board 1 with a conductor to which the heat-resistant conductor 60 is connected can be covered with the resin molding portion 70 to form a circuit module as shown in FIG. 5A.
The resin molding part 70 is a thermosetting selected from any one of an epoxy resin, a silicone resin, a phenol resin, a melamine resin, a urea resin, a polyamide resin, a polyimide resin, and a polyurethane resin having a thermal expansion coefficient close to that of the circuit component 51, for example. It can be formed using a functional resin.
Further, as shown in FIG. 5B, after the periphery of the circuit component 51 is covered with a thermosetting resin 70a having a thermal expansion coefficient close to that of the circuit component 51, the periphery thereof is polyphenyl sulfide resin, polybutylene terephthalate resin. Further, it may be covered with a thermoplastic resin 71 selected from any of polyamideimide resins.

With reference to FIG. 6, the circuit board 1b with an external connection conductor in the 2nd Embodiment of this invention is demonstrated. In the following embodiments, the same components as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
Further, in some of the embodiments 1a, 1b, 1c, and 1d shown below, the same numbers are used if there are differences in the configuration similar to the circuit board 1 with the external connection conductor in the first embodiment described above. Are differentiated by adding a, b, c, and d as branch numbers.
In the description of the above-described prior art shown as comparative examples in FIGS. 10, 11A, 11B, 11C, and 11D, the same configuration as that of the first embodiment of the present invention is the same according to the same rule. A reference numeral is attached, and even a similar structure is distinguished by attaching a z branch number to a structure including the problems of the prior art.
In the above embodiment, the land 200 is formed in a substantially U shape so as to surround the periphery of the notch 11 provided in the insulating substrate 10. However, in the circuit board 1 b with the external connection conductor of the present embodiment, As shown in FIG. 6, a main land 200b connected to the main solder portion 400b and a divided land 202b connected to the divided solder portion 401b may be formed, and each may be joined to the metal piece 50.
By dividing the land 200 into the main land 200b and the divided land 202, the load and vibration applied to the metal piece 50 from the outside at the time of conductor joining are further hardly transmitted to the land 200b, and land separation is further less likely to occur.
Further, at the boundary between the main land 200b and the divided land 202, a part of the main land 200b and a part of the divided land 202 are covered by the partial shielding portion 302b of the solder resist 30b. On the other hand, it will show stronger durability.

With reference to FIG. 7, the circuit board 1c with an external connection conductor in the 3rd Embodiment of this invention is demonstrated.
In the said embodiment, although the example which formed the metal piece 50 in flat form was shown, as shown in this embodiment, as shown in this embodiment, it has the substantially H shape which notched inward a part of both sides piece of the metal piece 50c. Further, the main solder part 400c may be divided into a plurality of parts, and the area of the land 200 covered by the partial shielding part 302c may be enlarged.
Even if the area of the main solder portion 400c is reduced, the metal piece 50c and the land 200 are firmly joined by the wet spread of the solder, so that sufficient bonding strength is ensured, and the solder portion is made smaller. However, since the area of the partial shielding layer 302c is increased, even if a force in the peeling direction acts on the land 200 when the metal piece 50c and the external connection conductor 60 are joined, the land peeling is further hardly caused. Can do.

With reference to FIG. 8A, FIG. 8B, and FIG. 8C, the circuit board 1d with an external connection conductor in the 4th Embodiment of this invention is demonstrated.
In the above embodiment, as an external connection conductor 60, an example has been described using the heat-resistant conductive lines covering the heat resistant conductive material 600 in the heat insulator 610, in this embodiment, shown in FIG. 8A The difference is that such a flexible wiring board 60d is used.
The flexible wiring board 60d is formed of a conductive foil 600d such as a copper foil on a flexible film-like flexible insulator 610d having high heat resistance such as polyimide, and the conductive foil 600d. to cover, flexible insulator 611 d is applied, the terminal portion 601d is exposed.
Further, in the case that requires heat resistance, a conductor foil 600d, it may be used heat resistant conductive foil plated with nickel or tin-plated copper foil or copper alloy foil.
Note that the flexible wiring board 60d in the present embodiment is not limited to a so-called FPC (flexible printed wiring board), and any FFC (flexible flat wiring board) can be applied.
The flexible wiring board 60d is rich in flexibility and thin, and is suitable for wiring of movable parts and wiring in places where mounting space is limited.
However, it is not possible to draw out only the conductor foil 600d which is a conductor , and the flexible insulating substrate 610d is attached with the terminal portion 601d of the heat-resistant conductor 600d of the flexible wiring substrate 60d. By exposing from the body 602, connection with another member becomes possible.
The conductor foil 600d used for the flexible wiring board 60d is generally made of copper foil and does not have poor solder wettability, but it is not always easy to connect directly to the terminal of the circuit board. In addition, like the circuit board 10 of the present invention, the conductive foil 600d of the flexible wiring board 60d is connected to the circuit through the metal piece 50 mounted in the groove part 101 which is partially cut off at the edge of the insulating substrate 100. It becomes easy to join the substrate 10.
In this embodiment, as shown in FIG. 8B, the metal piece 50 and the end portion 601d where the heat-resistant conductor (conductor foil) 600d of the flexible wiring board 60d is exposed from the flexible insulator 602 are overlapped. In addition, the joint P between the conductor foil 600d and the metal piece 50 is sandwiched from above and below between the welding tip CHP and the anvil ANV of the ultrasonic welding machine and subjected to ultrasonic vibration while applying a load. _By forming the _WLD , the two can be in a state of being firmly bonded to each other at the molecular level.
At this time, as shown in FIG. 8C, the metal piece 50 and the land 200 are separated from the portion connected by the solder layer 40 and the partial shielding portion 302 of the resistor layer 300, Since part of the land 200 is covered by the partial shielding portion 302 and the movement of the land 200 is restricted, it occurs when the conductor foil 600d and the metal piece 50 are ultrasonically welded as in the above embodiment. The force applied to the land 200 is dispersed, and further, a part of the land 200 is covered so that the partial shielding portion 302 of the solder resist 30 is bridged. the vibration of suppression, the land 200 without peeling from the surface of the insulating substrate 100, the circuit even when a flexible wiring board 60 d The reliability of electrical connection with the substrate 10 can be improved.

A circuit board 1e according to a fifth embodiment of the present invention will be described with reference to FIGS. 9A, 9B, and 9C.
In the above-described embodiment, the example in which the metal pieces 50 and 50c are connected to the outside via the heat-resistant conductor 60 or the flexible wiring board 60d has been described. However, in this embodiment, the external connection conductor 60e A connector 610e that fits into the other party as an insulator, and a conductor terminal portion 601e that is housed inside the connector 610e as a conductor, one end exposed from the connector 610e and joined to the metal piece 50c, and the other end The difference lies in that it is constituted by a metal piece terminal 600e constituting the connector terminal portion 602e connected to the other party inside the connector 610e.
As shown in FIG. 9A, the connector 610e is provided with a fitting means 81 such as a claw that fits when assembled to the other connector.
The connector 610e provided as an insulator for the external conductor is a known heat such as PBT (polypropylene terephthalate) resin, PPS (polyphenylene sulfide) resin, PEEK (polyether ether ketone) resin, fluororesin, polyamide resin, polyamideimide resin, or the like. A plastic resin is used, and the metal piece terminal 600e is held inside by a known manufacturing method such as insert molding.
For the metal piece terminal 600e, a heat-resistant conductor plate obtained by applying tin plating or nickel plating to a copper plate or a copper alloy plate, a heat-resistant conductor plate obtained by applying tin plating or nickel plating to a stainless steel plate, or the like can be used. .
As shown in FIG. 9C, a plurality of metal piece terminals 600e can be held inside the connector 610e, and the number thereof can be changed as needed.
Also in the present embodiment, as in the above-described embodiment, bonding such as resistance welding or ultrasonic welding is performed using the groove portion 101 in which the conductor end portion 601e exposed from the connector 610e and the metal piece 50c are provided in the insulating substrate 100. When joining by means, peeling between the metal piece 50c and the land 200 is difficult to occur.
In the present embodiment, an example in which the conductor end 601e and the metal piece 50c provided with the notch are joined is shown, but it is natural that the metal piece 50 without the notch can be used. .
In the present embodiment, after the connector 60e is assembled to the circuit board 10, the resin molding portion 70e is formed around the periphery using an epoxy resin or the like.

1, 1a, 1b, 1c, 1d, 1e Circuit boards with external connection conductors 10, 10b, 10c Circuit board 100 Insulating board 101 Groove parts 20, 20b Conductive layers 200, 200b, 202 Metal piece mounting land 201 Wiring part 30, 30b, 30c Solder resist 300 Conductor protection parts 301, 301b, 301c Land partial exposure openings (partial openings)
302, 302b, 302c Land partial shielding part (partial shielding part)
40, 40b, 40c Solder layer 50, 50c Metal pieces 60, 60d, 60e External connection conductors 600, 600d, 600e Conductors 601, 601d, 601e Conductor terminals 610, 610d, 611d, 610e Insulator for external conductor

2009-295945 2001-237526 gazette 2010-182778

Claims (13)

An insulating substrate (100) having a groove (101) with a part of the outer peripheral edge cut out inward;
A conductor layer (20) having a metal piece mounting land (200) provided on the surface around the groove (101) and a wiring portion (201) connected to at least a part of the metal piece mounting land (200). )When,
A substantially flat metal piece (50, 50c) that is soldered and fixed to the metal piece mounting land (200) across the groove (101),
A solder resist layer (30, 30b, 30c) provided between the metal piece (50, 50c) and the conductor layer (20);
External connection conductors (60, 600d, 600e) and external connection conductors (60, 610d, 611d, 610e) comprising external conductors (610, 610d, 611d, 610e) covering the conductors (600, 600d, 600e). 60d, 60e)
The external connection conductor (60, 60d, 60e) includes, as the conductor (600, 600d, 600e), a heat-resistant conductor having high heat resistance of 150 ° C. or more, and the conductor (600, 600d, 600e), the conductor terminal portions (601, 601d, 601e) exposed from the outer conductor insulator ( 610, 610d, 611d, 610e ) and the metal pieces (50, 50c) are connected to the groove portion ( 101) a circuit board with an external connection conductor joined and electrically connected to the outside,
The metal piece mounting land (200) has a land (200b) connected to the wiring part (201) on the opposite side of the opening of the groove part (101) and both sides of the groove part (101). Divided into the land (202) to be placed,
The solder resist layer (30, 30b, 30c)
A part of each divided metal piece mounting land (200b, 202) is exposed, and a land part exposing opening (301, 301b, 301c) which is an independent opening not communicating with the groove (101);
The metal piece mounting lands (200b, 202) are covered so as to surround the land portion exposure openings (301, 301b, 301c) and cover a part of the metal piece mounting lands (200b, 202). A partially shielding land partial shielding portion (302, 302b, 302c),
The metal piece mounting land and (200b, 202) the metal strip and (50,50C) comprises an upper Kira command portion exposure opening portion (301,301b, 301c) solder layer provided inside the (40, 40b, 40c),
The conductor terminal portions (601, 601d, 601e) are inserted into the groove portion (101), and in the space surrounded by the metal pieces (50, 50c) and the insulating substrate (100), A circuit board (1, 1a, 1b, 1c, 1d, 1e) with external connection conductors, which is joined to the pieces (50, 50c) by welding. The external connection conductor (60, 60d, 60e)
2. The circuit board with external connection conductor according to claim 1, comprising a heat-resistant insulator having high heat resistance of 150 ° C. or more as the insulator for external conductor (610, 610 d, 611 d, 610 e). 1a, 1b, 1c, 1d, 1e). The external connection conductor is
The conductor has a substantially flat conductor foil (600d),
The circuit board with an external connection conductor according to claim 1 or 2, which is a flexible wiring board (60d) comprising a flexible insulator (610d, 611d) having flexibility as the external conductor insulator. 1d). The external connection conductor (60e)
As the insulator, a connector (610e) fitted to the other party is provided,
The conductor for the external conductor is housed inside the connector (610e), and one end is exposed from the connector (610e) to form a conductor terminal portion (601e) that joins the metal piece (50, 50c). The circuit board (1e) with an external connection conductor according to claim 1 or 2, further comprising a metal piece terminal (600e) constituting a connector terminal portion (602e) whose other end is connected to the other side inside the connector (610e). ). The heat-resistant conductor (600, 600d, 600e)
Heat-resistant conductor wire (600) in which an annealed copper wire subjected to tin plating or nickel plating is used as a stranded wire,
A heat-resistant conductor wire (600) in which a nickel-plated annealed copper wire and a stainless steel wire are stranded,
Heat-resistant conductor wire (600) in which an aluminum wire is a stranded wire,
Heat-resistant conductor foil (600d) obtained by applying tin plating or nickel plating to copper foil,
A heat-resistant conductor plate (600e) obtained by performing tin plating or nickel plating on a copper plate or a copper alloy plate;
4. The circuit board (1, 1 a, 1 b, 1 c) with an external connection conductor according to claim 1, wherein the heat-resistant conductor plate (600 e) is obtained by applying tin plating or nickel plating to a stainless steel plate. 1d, 1e). The outer conductor insulator ( 610, 610d, 611d ) is made of any one of fluororubber, fluororesin, silicone rubber, silicone resin, polyimide, polyamide, crosslinked polyethylene, crosslinked vinyl chloride, and glass fiber. A circuit board (1, 1a, 1b, 1c, 1d) with an external connection conductor according to any one of the above.   The said insulator for external conductors (610e) consists of PBT (polypropylene terephthalate) resin, PPS (polyphenylene sulfide) resin, PEEK (polyether ether ketone) resin, a fluororesin, and a polyamide resin. Circuit board with external connection conductor (1e).   The metal material constituting the metal piece (50, 50c) is copper, copper alloy, nickel, nickel alloy (Ni / SUS / Ni clad steel), nickel / copper / palladium / silver / tin / platinum / gold plating. The circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external connection conductor according to any one of claims 1 to 6, wherein the circuit board is an applied steel material.   The insulating substrate (100) is a printed circuit board including an insulating resin substrate selected from polyimide, polyamideimide, aramid, and glass epoxy resin, and the solder resist layer (30) is made of a photo-curing resin. The circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external connection conductor according to any one of claims 1 to 8, comprising an insulating resin material.   The insulating substrate (100) is a ceramic substrate of alumina, titania, magnesia, or spinel, and the solder resist layer (30) is selected from quartz glass or borosilicate glass. The circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external connection conductor according to any one of claims 1 to 8, which is made of a glass material. It is a manufacturing method of a circuit board with an external connection conductor according to any one of claims 1 to 10,
The conductor layer (20) is formed on the surface of the insulating substrate (100) on which the conductor layer (20) including at least the wiring part (201) and the metal piece mounting land (200, 200b, 202) is formed. A solder resist forming step of forming a solder resist layer (30, 30b, 30c) that makes it possible to solder the predetermined portion of the predetermined portion, prevents solder from being attached to the predetermined portion, and insulates and protects the predetermined portion;
A mounting step of mounting the metal piece (50, 50c),
In the solder resist forming step, the solder resist layer (30, 30b, 0c) exposes a predetermined portion of the metal piece mounting land (200, 200b, 202) to a partial opening (301, 301b, 301c). And partial shielding portions (302, 302b, 302c) that cover predetermined portions,
In the mounting step, the solder layer (40, 40b, 40c) for fixing the metal piece mounting land (200, 200b, 202) and the metal piece (50, 50c) is formed into the metal piece mounting land (200, 200b, 202) are exposed from the land part exposure openings (301, 301b, 301c) provided at a plurality of locations, and the metal piece mounting lands (200, 200b, 202) are divided at a plurality of locations. A method of manufacturing a circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external connection conductor, characterized by joining to metal pieces (50, 50c). By using at least the groove (101) provided in the insulating substrate (100), the end portions (601, 601d, 601e) of the metal pieces (50, 50c) and the external connection conductors ( 60, 60d, 60e ) are used. And a conductor joining step for joining them so as to be sandwiched by joining means. The method for manufacturing a circuit board (1, 1a, 1b, 1c, 1d, 1e) with an external connection conductor according to claim 11.   The method for manufacturing a circuit board with an external connection conductor according to claim 12, wherein the joining means used in the conductor joining step is either ultrasonic welding (USW) or resistance welding (RW).

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