Heater chip, and heating joint method for electrode and conducting wire

Abstract

To provide a heater chip capable of reducing a time until a heating part after stopping heating is cooled down to a prescribed temperature, and a heating joint method of electrodes and conducting wire using the heater chip.SOLUTION: A heating part is in a lower part of a plate-like chip base material, and a radiation fin is inside the chip base material in an upper part of the chip base material. The heating part is separated into two or more parts in a lateral width direction of the chip base material, generates heat at different temperatures when conducted, and can pressure / heat conducting wire and electrodes. A root side of the radiation fin is separated into two or more, and a heat radiation is one or separate from the root side to the heat radiation. The radiation fin can conduct heat of the heating part from the root side to the heat radiation part above, and can radiate it outside.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heater chip used to electrically connect a conductor to an electrode, and a method for heat-bonding an electrode and a conductor using the heater chip. [Background technology]

[0002] Heat-generating bonding using heater chips is used to electrically connect conducting wires and terminals (called "conductors") drawn from electronic components and external circuits to the joining points (called "electrodes") of electrical circuits, terminals, electrodes, etc. on printed circuit boards, ferrite core alumina substrates, lead frames, etc. (called "substrates"). Heat-generating bonding using heater chips can be done by soldering or by high-temperature pressure diffusion bonding, which does not use solder.

[0003] Heater chips come in a variety of shapes and structures. Heater chips are generally made from a high-melting-point metal such as tungsten or molybdenum as the base material. Conventional heater chips are shown in Figures 4 and 5.

[0004] The heater chip A in Fig. 4 has a soldering iron part (heat generating part) C below (on the bottom surface of) two forked connecting parts B1 and B2. The heater chip A can be connected to a heater head E by screwing a fastener D into the fastening holes of the connecting parts B1 and B2 (Patent Documents 1 to 3).

[0005] Heater chip A in Figure 5 has two bifurcated connecting parts B1 and B2, below which there is a current passing part J with a narrow cross-sectional area to increase current density, and below (on the bottom surface of) current passing part J there is a soldering iron part (heat generating part) C.

[0006] The heater head E in Figures 4 and 5 can raise and lower the heater chip A, and when lowered, the heat-generating part C of the heater chip A can be brought into contact with the conductive wire H placed on the electrode G and pressed downward.

[0007] Figure 4 shows an example of diffusion bonding. In Figure 4, heater chip A is lowered by heater head E, and while heating portion C of heater chip A is pressed against conductor H and pressure is applied, power is supplied from a heater power supply (not shown) to one connecting portion (power supply portion: input side) B1 of heater chip A. Current flows through heating portion C as shown by arrow a in Figure 4 to the other connecting portion (current-carrying portion: output side) B2, generating heat at heating portion C. This heat and the pressure pressurize and heat conductor H and electrode G, and conductor H is instantly diffusion-bonded to electrode G. If conductor H has an insulating coating, the heat melts and peels off the insulating coating, and the exposed conductor H is bonded to electrode G.

[0008] Figure 5 shows an example of soldering. In Figure 5, cream solder I is placed on electrode G, and conductor H is placed on top of that. Heater tip A is lowered with heater head E, and heat-generating part C of heater tip A is pressed against conductor H while applying pressure. When power is supplied from a heater power supply to one power supply part B1 of heater tip A, current flows to current passing part J as shown by arrow a in Figure 5, increasing the current density, and then flows through heat-generating part C to the other current-carrying part B2, generating heat at heat-generating part C. This heat generation and the pressure applied pressurize and heat conductor H and electrode G, melting the cream solder I and instantly forming a diffusion bond between conductor H and electrode G.

[0009] When the diameter (wire diameter) of the conductor H is about 30 μm, the thickness of the electrode G is about 30 to 40 μm and flat, and the heating time is about 200 μsec, the heat generation temperature is generally about 700 to 800°C for diffusion bonding and about 450°C for solder bonding.

[0010] The conductors of flat cables are either round or rectangular. Both soldering and diffusion bonding can be used for both types of conductors.

[0011] Thermal bonding is not limited to cases where one conductor H is bonded to one electrode G, but can also involve bonding two or more conductors H to one electrode G, or bonding a conductor H to each of two or more electrodes G. The two or more conductors H may have the same or different wire diameters. To reliably thermally bond these conductors H, it is desirable to change the heating temperature of the heating element C of the heater chip A according to the number and diameter of the conductors H. However, conventional heater chips A have only one heating element C, and the heating temperature is the same across the entire heating element, making it difficult to thermally bond two or more conductors H at different temperatures simultaneously. As a result, it was necessary to switch the heating temperature of the heater chip A and apply pressure and heat to each conductor H separately, or to switch to a heater chip A with a different heating temperature and apply pressure and heat to it, making the thermal bonding process cumbersome and inefficient.

[0012] In exothermic bonding using heater chip A, whether it is diffusion bonding as shown in Figure 4 or solder bonding as shown in Figure 5, power supply to heater chip A ends when a predetermined time (power supply time) has elapsed since the start of power supply (power supply time), and heat from heat-generating part C is allowed to dissipate within a predetermined time (cooling time) after power supply has stopped. When heat-generating part C has cooled to a predetermined temperature (usually room temperature), heater head E lifts (pulls back) heater chip A, separating heat-generating part C from conductor H. The following cycle is then repeated to exothermically bond conductor H and electrode G: lowering heater chip A onto conductor H, applying pressure, starting power supply to power supply part B1 of heater chip A, heat generated by heat-generating part C of heater chip A causing a thermal bonding between conductor H and electrode G, stopping power supply, heat dissipation from heat-generating part C causing a temperature drop in heat-generating part C, and lifting heater chip A.

[0013] Because lead frame (substrate) F has extremely high thermal conductivity (thermal diffusion), unless the heat generated by heat generating part C of heater chip A rises in temperature more rapidly than the heat loss due to thermal diffusion of lead frame F, it is difficult to achieve thermal bonding and a strong bond.

[0014] Conventionally, a temperature sensor (e.g., a thermocouple: Figure 4) K is attached near the heat-generating part C of the heater chip A, and the thermocouple K measures the temperature of the heat-generating part C. A control circuit (not shown) controls the power supply to the heater chip A so that the temperature measured by the thermocouple K becomes the desired set value, thereby ensuring reliable and stable heat bonding.

[0015] However, in both the diffusion bonding shown in Figure 4 and the solder bonding shown in Figure 5, when the exothermic bonding of the conductor H and electrode G is repeated, the heat generated at the heat-generating portion C of the heater chip A is stored in the connecting portions B1 and B2 through thermal conduction, causing the temperature to rise and saturate. As the temperature rises, the electrical resistance of the connecting portions B1 and B2 increases, reducing the current flowing to the heat-generating portion C and reducing the heat generation efficiency. Furthermore, when the temperature of the connecting portions B1 and B2 rises, it becomes difficult for the heat-generating portion C to dissipate heat, so it takes time for the heat-generating portion C to cool down to the set temperature after the power supply is stopped, lengthening the cycle time and reducing the efficiency of the bonding work. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] Patent No. 3917964 [Patent Document 2] Patent No. 5794577 [Patent Document 3] Patent No. 6148800 Summary of the Invention [Problem to be solved by the invention]

[0017] The problem to be solved by the present invention is to provide a heater chip that can heat-bond two or more conductors at different temperatures simultaneously with one heater chip, and that is resistant to temperature increases at the connecting parts of the heater chip even when pressure and heat are repeatedly applied, and therefore is less likely to increase electrical resistance, and to provide a method for heat-bonding electrodes and conductors using such a heater chip. [Means for solving the problem]

[0018] [Heater tip] The heater chip of the present invention has two or more heat generating sections with different heat generation amounts provided on the bottom of a plate-shaped chip substrate. Each heat generating section generates heat when current is applied. The two or more heat generating sections are separated into two or more sections in the width direction of the heater chip. The heat generation amounts are made different by making the cross-sectional areas of the two or more separated heat generating sections different. The cross-sectional areas of the two or more heat generating sections are made different by making both or either one of the width and thickness different.

[0019] A heat dissipation fin is connected to each heat-generating portion. Each heat dissipation fin is located inside the chip substrate. Only the base of the heat dissipation fin is separated, and the portion from the base to the tip (upper portion) is a single heat dissipation portion. The heat dissipation fin may be separate from the base to the heat dissipation portion, with the base continuing to each heat-generating portion. In either case, the outer periphery of the heat dissipation portion of the heat dissipation fin is separated from the chip substrate by a heat dissipation space. With this structure, heat from each heat-generating portion is transferred from the base side of the heat dissipation fin to the heat dissipation portion of the heat dissipation fin and then dissipated to the outside of the heater chip, reducing the amount of heat transferred to the connecting portion of the heater chip and making it less likely for heat to accumulate in the connecting portion (making it less likely for electrical resistance to increase).

[0020] [Method for thermally joining electrodes and conductors] The method of exothermic bonding of electrodes and conductors using a heater chip of the present invention supplies power to the heater chip to generate heat in each heat-generating portion, and then applies pressure and heat to two or more conductors arranged on the electrode using each heat-generating portion to exothermically bond the conductors to the electrode. After exothermic bonding, power supply to the heater chip is stopped to stop the heat generation of the heat-generating portions, and the heat from each heat-generating portion is dissipated to the outside of the heater chip using heat dissipation fins, allowing each heat-generating portion to cool (cool) to a predetermined temperature, and then the heater chip is separated from the conductors. At least after power supply is stopped, the heat from each heat-generating portion is dissipated to the outside of the heater chip using the heat dissipation fins, suppressing thermal conduction of the heat-generating portions to the connecting portions of the heater chip, suppressing heat accumulation in the connecting portions, and suppressing an increase in electrical resistance in the connecting portions. [Effects of the Invention]

[0021] The heater chip of the present invention has the following effects. (1) Two or more heat generating parts with different heat generating temperatures can simultaneously apply pressure and heat to two or more conductors to heat-bond them to the electrode, so even two or more conductors with different wire diameters or two or more conductors in multiple rows can be heated at the appropriate temperature and heat-bonded. (2) Because the heat from each heat generating part is dissipated to the outside by the heat dissipation fins, the connecting parts of the heater chips are less likely to accumulate heat. This makes it less likely for the electrical resistance of the connecting parts to increase, and makes it easier to control the temperature of the heat generating parts by controlling the power supply to them. (3) Since the heat from the heat-generating part is dissipated to the outside by the heat dissipation fins, the time it takes for the heat-generating part to dissipate heat after power supply is stopped is shortened, the work cycle for heat-generating joining can be shortened, and the work efficiency of the joining work can be improved.

[0022] The method for exothermic bonding of an electrode and a conductor according to the present invention has the following effects. (1) Two or more conductors are thermally joined separately using two or more heat generating parts with different heat outputs, so that the conductors can be heated to an appropriate temperature according to the wire diameter of the conductors. (2) Since two or more conductors are thermally joined simultaneously by two or more heating parts, the efficiency of the thermal joining process is improved. (3) Since the heat from the heat generating part is dissipated to the outside by the heat dissipation fins, the heat from the heating part is less likely to accumulate in the connecting part of the heater chip, the increase in electrical resistance of the connecting part due to heat accumulation is reduced, the power supply to the heat generating part can be controlled, and the temperature of the heat generating part can be easily controlled. (4) At least after power supply is stopped, the heat from the heat generating part is dissipated to the outside by the heat dissipation fins, which accelerates the temperature drop of the heater chip after power supply is stopped, and also shortens the repeated cycle of heat generating bonding-heat dissipation-detaching the heat generating part from the bonded part, thereby improving the work efficiency of heat generating bonding. [Brief explanation of the drawings]

[0023] [Figure 1] 1A and 1B are a front view and a side view, respectively, of an example of a heater chip according to the present invention. [Figure 2] 1A and 1B are explanatory diagrams of different examples of diffusion bonding using the heater chip of the present invention, and 1C and 1D are explanatory diagrams of different examples of solder bonding. [Figure 3]4(a) to 4(c) are explanatory views of different examples of diffusion bonding using the heater chip of the present invention. [Figure 4] FIG. 10 is an explanatory diagram of diffusion bonding using a conventional heater chip. [Figure 5] FIG. 10 is an explanatory diagram of soldering using a conventional heater chip. DETAILED DESCRIPTION OF THE INVENTION

[0024] (Embodiment 1 of the heater chip) An example of an embodiment of the heater chip of the present invention will be described with reference to the drawings. The heater chip 1 in Figures 1(a) and 1(b) has a connecting portion 3 on the top of a plate-shaped chip substrate 2. A current passing portion 4 is located at the tip side of the connecting portion 3 (the lower end side in Figure 1(a)). A heat generating portion 5 is located at the end of the current passing portion 4 (the lower end side in Figure 1(a)), and a heat dissipation fin 6 is located inside the chip substrate 2 (approximately in the center).

[0025] [Chip substrate] The material of the chip substrate 2 is the same as that of the conventional heater chip A (Figs. 4 and 5), and is made of a high-melting-point metal such as tungsten or molybdenum. The chip substrate 2 is formed by processing a plate material several mm thick (for example, about 2 to 4 mm) using wire electric discharge machining or other processing methods.

[0026] [Connection part] Similar to the conventional heater chip A, the connecting portion 3 is separated into two bifurcated connecting portions 3a and 3b in the width direction (left and right in Figure 1(a)) by a vertically elongated separation space 7. Each connecting portion 3a, 3b has a fastening hole 8, and by screwing fasteners (screws) D into these fastening holes 8 as shown in Figures 4 and 5, the heater chip 1 can be fixed to the heater head E as shown in Figures 4 and 5. One of the connecting portions 3 (which is also the power supply portion) can be supplied with a heating current from a power source (not shown).

[0027] [Current passing section] The part of the chip substrate 2 below the connecting portion 3 is the current passing portion 4. As shown in Figure 1(a), the current passing portion 4 is narrower in width than the connecting portion 3, and as shown in Figure 1(b), it is thinner than the connecting portion 3 to reduce its volume, thereby increasing the density of the current flowing from the connecting portion 3. The current passing portion 4 in Figure 1(a) is separated in the width direction by a separation space 10, resulting in two current passing portions 4a and 4b with different widths.

[0028] [Heat generating part] The heat generating portion 5 in Figure 1(a) is located at the tip (bottom end) of the current passing portion 4. The heat generating portion 5 is also separated in the width direction by a separation space 10 into two heat generating portions 5a and 5b of different widths. The two heat generating portions 5a and 5b are continuous with the current passing portions 4a and 4b, so that when the current supplied to the connecting portion (power supply portion) 3a passes through the current passing portions 4a and 4b and flows into the heat generating portions 5a and 5b, the heat generating portions 5a and 5b instantly generate heat.

[0029] The two heat generating parts 5a and 5b have different widths. When current is applied to the heat generating parts 5a and 5b, Joule heat (I 2 1(a), the heat generating portions 5a and 5b have the same length, but the width of the heat generating portion 5a is narrower than the width of the heat generating portion 5b, so the electrical resistance of the heat generating portion 5a is greater than the electrical resistance of the heat generating portion 5b. When the same current is passed through them, the heat generating portion 5a, which has a higher electrical resistance, generates heat more easily than the heat generating portion 5b, which has a lower electrical resistance. In either case, the design is such that the required amount of heat is obtained.

[0030] The heat generating portion 5 may be separated into three or more portions. In this case, the current passing portions 4 connected to the heat generating portion 5 and the root sides of the heat dissipation fins 6 connected to the current passing portions 4 are also separated into three or more portions by separation spaces 10 according to the number of heat generating portions 5. The three or more separated heat generating portions 5 have different widths to generate different amounts of heat. The shape of the heat generating portion 5 is rectangular in FIG. 1(a), but it can also be a trapezoidal shape with a flared bottom or a concave shape with a flared bottom.

[0031] [Heat dissipation fins] The heat dissipation fin 6 in Figure 1(a) is provided inside (approximately at the center) of the chip substrate 2, separating it with a groove-shaped heat dissipation space 9. The base sides 6a and 6b of the heat dissipation fin 6 are separated by a separation space 10 to the same width as the current passing portions 4a and 4b, and the two separated base sides 6a and 6b are continuous with the two current passing portions 4a and 4b, respectively. The upper part (heat dissipation portion) 6c of the heat dissipation fin 6 is not separated but is formed as a single plate.

[0032] The heat dissipation fins 6 dissipate heat generated by the heat-generating portions 5a, 5b due to power supply to the outside of the heater chip 1, reducing the amount of heat transferred to the connecting portion (power supply portion) 3a and the connecting portion (current-carrying portion) 3b. This makes it difficult for heat to accumulate in the connecting portions 3a, 3b, and prevents an increase in the electrical resistance of the connecting portions 3a, 3b. This makes it easier to control the temperature of the heat-generating portions 5a, 5b by controlling the power supply to the heat-generating portions 5a, 5b. Furthermore, the time it takes for the heat-generating portions to dissipate heat after power supply is stopped is shortened, shortening the heat-generating joining work cycle and improving the work efficiency of the joining work.

[0033] The heat dissipating fin 6 may be separated into two pieces by separating the base sides 6a, 6b from the heat dissipating portion 6c, rather than by the separation space 10. Also, instead of separating one heat dissipating fin 6 by the separation space 10, the base sides of two or more separate heat dissipating fins 6 may be connected to the current passing portion 4.

[0034] The surface of the heat dissipation fin 6 can be coated with a metal with good heat dissipation properties to speed up heat dissipation. There are various coating methods, but for example, a metal with good heat dissipation properties can be coated by sputtering it onto the heat dissipation fin base material. The heat dissipation fin 6 in Figure 1(a) is flat, but if possible, it can be made corrugated or have other shapes or structures to increase the surface area and speed up heat dissipation.

[0035] The shape of the heat dissipation portion 6c of the heat dissipation fin 6 can be circular, heart-shaped, or any other shape. The thickness can also be any other thickness. In either case, it is designed to improve heat dissipation efficiency. The shape, size, etc. of the heat dissipation space 9 and the separation space 10 are also designed to improve heat dissipation.

[0036] [Temperature sensor] In Fig. 1(a), a temperature sensor (e.g., a thermocouple) 11 is attached to each of the two separated heat generating parts 5a and 5b. The temperature sensor 11 is electrically connected to an external temperature control unit (not shown) via lead wires 12. The temperature sensor 11 may be a general-purpose sensor or a newly developed sensor.

[0037] (Heater Chip Embodiment 2) In the heater chip 1 of embodiment 1, the current passing portion 4 has a thin wall thickness and a narrow width to reduce the cross-sectional area, but if a current density sufficient for heat generation can be obtained in the heat generating portion 5, the current passing portion 4 may not be provided. In this case, the base sides 6a, 6b of the heat dissipation fin 6 are directly connected to each of the two or more heat generating portions 5a, 5b.

[0038] (Heater Chip Embodiment 3) The heater chip of the present invention may have a recess that is approximately semicircular in side view in the heat generating portion 5, similar to the heat generating portion C of the heater chip A in Fig. 5. The recess may have other shapes, such as a downward-facing rectangular shape, a V-shape, or a trapezoidal shape in side view. The number of recesses may also be, for example, one or three or more.

[0039] In the method for heat-bonding an electrode and a conductor of the present invention, the heater chip 1 (FIGS. 1(a) and 1(b)) of the present invention is attached to a heater head E as shown in FIGS. 4 and 5. In this case, the heater chip 1 is raised and lowered by the heater head E.

[0040] (Embodiment 1 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of electrodes and conductors in the first embodiment, conductors 14a and 14b are placed on two different electrodes 13a and 13b, as shown in FIG. 2(a). The heater chip 1 is then lowered using the heater head E (FIG. 4), and the heat-generating portion 5a presses the conductor 14a, while the heat-generating portion 5b presses the conductor 14b. A heating current is supplied from a heater power supply (not shown) to one connecting portion 3a of the heater chip 1, and the supplied current flows from the connecting portion (power supply portion) 3a to the current passing portions 4a and 4b to the heat-generating portions 5a and 5b to the other connecting portion (current-carrying portion) 3b, as shown by arrow a in FIG. 1. In this case, the current density is increased in the current passing portions 4a and 4b, generating Joule heat in the respective heat-generating portions 5a and 5b. This Joule heat pressurizes and heats the electrode 13a and the conductor 14a, and the electrode 13b and the conductor 14b, thereby exothermally bonding them (the same applies below).

[0041] After the electrodes 13a and 13a are thermally bonded to the conductors 14a and 14b as described above, power supply to the heater chip 1 is stopped to stop the heat generation by the heat generating portions 5a and 5b. At least after power supply is stopped, the heat dissipation portion 6c of the heat dissipation fin 6 dissipates heat from the heat generating portions 5a and 5b, reducing thermal conduction to the connecting portions 3a and 3b of the heater chip 1, suppressing heat accumulation in the connecting portions 3a and 3b, and preventing an increase in electrical resistance. The temperature of the heat generating portions 5a and 5b is also accelerated after power supply is stopped (the same applies below). Once the temperature has dropped to a predetermined level, the heater head E (FIG. 4) raises the heater chip 1 to separate the heat generating portions 5a and 5b from the bonded conductors 14a and 14b. Thereafter, the heat bonding by applying pressure and heat, stopping heat generation, and heat dissipation are repeated, and the heat bonding is repeated. This also applies to the following embodiments.

[0042] Electrodes 13a and 13b are junctions for electrical circuits, terminals, electrodes, etc. of various substrates such as printed circuit boards, ferrite core alumina substrates, and lead frames, and are made of copper alloys, iron-nickel alloys, or other conductive materials, as with conventional electrodes of this type (the same applies below). Electrodes 13a and 13b may be thin, flat, or thick, block-shaped (measured in μm in either case). In the case of a block shape, the width is wider than the diameter of conductor wires 14a and 14b, and the thickness is thicker than the diameter of conductor wires 14a and 14b. Conductor wires 14a and 14b are, for example, copper or aluminum wires with a diameter of approximately 30 μm, and may be coated, bare, or otherwise. This also applies to the following embodiments.

[0043] (Embodiment 2 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of an electrode and a conductor in embodiment 2, conductors 14a and 14b are placed on one electrode 13 as shown in Figure 2(b), heater chip 1 is lowered using heater head E (Figure 4), and heat generating portion 5a presses conductor 14a, and heat generating portion 5b presses conductor 14b. A heating current is supplied from a heater power supply (not shown) to connecting portion 3 of heater chip 1, the current density is increased in current passing portions 4a and 4b, and Joule heat is generated in each of heat generating portions 5a and 5b, thereby applying pressure and heat to electrode 13 and conductors 14a and 14b to exothermally bond them.

[0044] (Embodiment 3 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of electrodes and conductors in embodiment 3, as shown in Figure 2(c), cream solder I is placed on two electrodes 13a, 13b, conductors 14a, 14b are placed on top of that, heater chip 1 is lowered with heater head E (Figure 4), and heat generating portion 5a presses conductor 14a, and heat generating portion 5b presses conductor 14b. A heating current is supplied from a heater power supply (not shown) to connecting portion 3 of heater chip 1, the current density is increased in current passing portions 4a, 4b, and each of heat generating portions 5a, 5b is heated by Joule heat, thereby applying pressure and heat to electrode 13a and conductor 14a, and electrode 13b and conductor 14b to exothermic bond them.

[0045] (Embodiment 4 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of an electrode and a conductor in embodiment 4, as shown in Figure 2(d), cream solder I is placed on one electrode 13, conductors 14a and 14b are placed on top of that, heater chip 1 is lowered with heater head E (Figure 4), and heat generating portion 5a presses conductor 14a, and heat generating portion 5b presses conductor 14b. A heating current is supplied from a heater power supply (not shown) to connecting portion 3 of heater chip 1, the current density is increased in current passing portions 4a and 4b, and each of heat generating portions 5a and 5b is heated by Joule heat, thereby applying pressure and heat to electrode 13 and conductors 14a and 14b to exothermic bond them.

[0046] (Embodiment 5 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of an electrode and a conductor in embodiment 5, conductors 14a and 14b of different diameters are placed on one electrode 13 as shown in Figure 3(a), heater chip 1 is lowered using heater head E (Figure 4), and heat generation portion 5a presses conductor 14a, and heat generation portion 5b presses conductor 14b. A heating current is supplied from a heater power supply (not shown) to connecting portion 3 of heater chip 1, the current density is increased in current passing portions 4a and 4b, and Joule heat is generated in each of heat generation portions 5a and 5b, thereby pressurizing and heating electrode 13 and conductors 14a and 14b to exothermically bond them.

[0047] (Embodiment 6 of the method for thermally joining an electrode and a conductor) 3(b), the method for exothermic bonding between an electrode and a conductor in embodiment 6 involves placing one thin conductor 14a and two thicker conductors 14b (conductors of the same diameter) on one electrode 13, lowering heater chip 1, and applying pressure to conductor 14a with heat-generating portion 5a and conductor 14b with heat-generating portion 5b. A heating current is supplied to heater chip 1, increasing the current density at current-passing portions 4a and 4b, causing heat to be generated in heat-generating portions 5a and 5b, thereby applying pressure and heat to electrode 13 and conductors 14a and 14b, thereby exothermally bonding them.

[0048] (Embodiment 7 of the method for thermally joining an electrode and a conductor) In the method for exothermic bonding of electrodes and conductors in embodiment 7, one thick conductor 14a is placed on one electrode 13a, which are separated as shown in Figure 3(c), and two thin conductors 14b (conductors of the same diameter) are placed on the other electrode 13b, and heater tip 1 is lowered using heater head E (Figure 4), and heat is applied to conductor 14a by heat-generating portion 5a and to conductor 14b by heat-generating portion 5b. A heating current is supplied to heater tip 1, the current density is increased by current passing portions 4a and 4b, and heat is generated in heat-generating portions 5a and 5b, thereby applying pressure and heat to electrode 13a and conductor 14a, and electrode 13b and conductor 14b, thereby exothermally bonding them.

[0049] (Embodiment 8 of the method for thermally joining an electrode and a conductor) In the cases of Figures 3(a) to (c), cream solder I can also be placed on the electrodes 13 (13a, 13b) as shown in Figure 5, and the conductive wires 14a, 14b can be placed on the cream solder I, and the conductive wires 14a, 14b and the electrodes 13 (13a, 13b) can be pressurized and heated by the two heat generating parts 5a, 5b of the heater chip 1, thereby simultaneously thermally joining the two conductive wires 14a, 14b to the electrodes 13 (13a, 13b).

[0050] (Embodiment 9 of the method for thermally joining an electrode and a conductor) When one heater chip 1 has three or more heat generating parts, the conductor wires arranged on one electrode or on each of three or more electrodes can be simultaneously pressurized and heated to heat and bond them together. In this case, the diameters of the conductor wires can be the same or different.

[0051] In any of the methods for exothermic bonding of electrodes and conductors of the present invention, the heat generation temperature of the heat generating portion 5 (5a, 5b) is set to a temperature suitable for exothermic bonding of the conductors 14a, 14b and the electrodes 13 (13a, 13b). In this case, the temperature sensor 11 senses the heat generation temperature of the heat generating portion 5 (5a, 5b), and the temperature can be controlled by the temperature control portion based on that temperature. [Industrial Applicability]

[0052] The above embodiment is merely one example of the present invention. The materials, shapes, sizes, thicknesses, widths, heat generation temperatures, timing and time control conditions of the power supply current, etc. of the chip substrate 2, connecting portions 3 (3a, 3b), heat generating portions 5 (5a, 5b), and heat dissipation fins 6 can be designed to solve the problems of the present invention and to be easy to mold, use, heat, and dissipate heat. The widths and shapes of the heat dissipation space 9 and separation space 10 can also be designed to achieve the desired purpose.

[0053] The electrodes may be separated into three or more. The conducting wires arranged on the electrodes may be of different thicknesses or the same. Three or more conducting wires may be arranged on one electrode and thermally joined. [Explanation of symbols]

[0054] 1 heater chip 2 Chip substrate 3 Connecting part 3a Left side connection (power supply) 3b Right-side connection (electrical part) 4 Current passing section 4a (Left side) current passage 4b (right side) current passage 5 Heat generating part 5a (Left side) heating element 5b (right side) heating element 6 Heat dissipation fins 6a, 6b (radiation fin) base side 6c (heat dissipation fin) upper part (heat dissipation part) 7 Separation space 8 Stopper holes 9 Heat dissipation space 10 Separation space 11 Temperature Sensor 12 Lead Wires 13 electrodes 13a (left) electrode 13b (right) electrode 14a conductor 14b conductor A heater tip B1 Connection section (power supply section) B2 Connection part (current carrying part) C Heating part (soldering iron part) D. Fastener E heater head F Lead frame (substrate) G electrode H conductor I Cream solder J Current passing section K Temperature sensor (thermocouple)

Claims

1. The chip substrate has two or more heat generating parts and heat dissipation fins. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The base side of the heat dissipation fin is separated into two or more parts, and a heat dissipation section is located above the base side. Each separated base side is connected to each heat generating section, and heat from each heat generating section is transferred from each base side to the heat dissipation section and dissipated from the heat dissipation section to the outside. A heater chip characterized by:

2. The chip substrate has two or more heat generating parts and heat dissipation fins. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The heat dissipation fin is located inside the chip substrate, and the base side is separated into two or more parts, and a heat dissipation section is located above the base side, and each separated base side is continuous with each heat generating section, so that heat from each heat generating section is transferred from each base side to the heat dissipation section and dissipated from the heat dissipation section to the outside. A heater chip characterized by:

3. The chip substrate has two or more heat generating parts and heat dissipation fins. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The heat dissipation fin is divided into two or more base sides, and one heat dissipation section is located above the two or more base sides, and each base side is continuous with each heat generating section, so that heat from each heat generating section is transferred from each base side to one heat dissipation section and dissipated from the heat dissipation section to the outside of the chip substrate. A heater chip characterized by:

4. The chip substrate has two or more heat generating parts and two or more heat dissipation fins. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The two or more heat dissipation fins have heat dissipation portions above their base sides, and the base sides of each are continuous with the respective heat generating portions, so that heat from each heat generating portion is transferred from the base side of each heat dissipation fin to the heat dissipation portion of each heat dissipation fin, and is dissipated from each heat dissipation portion to the outside of the chip substrate. A heater chip characterized by:

5. The chip substrate has two or more heat generating parts, a current passing part that increases the current density, and a heat dissipation fin. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The current passing portion has an upper portion that is continuous with the power supply portion of the chip substrate, and a lower portion that is separated into two or more portions in the width direction of the chip substrate and is continuous with each of the two or more heat generating portions, The base side of the heat dissipation fin is divided into two or more parts, and a heat dissipation section is located above each base side. The base side is connected to the heat generating section via a current passing section, and heat from the heat generating section is transferred from the base side through the current passing section to the heat dissipation section, and is then dissipated from the heat dissipation section to the outside of the chip substrate. A heater chip characterized by:

6. The chip substrate has two or more heat generating parts, a current passing part that increases the current density, and a heat dissipation fin. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The upper part of the current passing part is continuous with the power supply part of the chip substrate, and the lower part is separated into two or more parts in the width direction of the chip substrate and is continuous with each of the heat generating parts, The heat dissipation fin is located inside the chip substrate, and has a heat dissipation section above the base side, and the base side is connected to the heat generating section via a current passing section, so that heat from the heat generating section is transferred from the base side through the current passing section to the heat dissipation section, and is then dissipated from the heat dissipation section to the outside. A heater chip characterized by:

7. The chip substrate has two or more heat generating parts, a current passing part that increases the current density, and a heat dissipation fin. The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The upper part of the current passing part is continuous with the power supply part of the chip substrate, and the lower part is separated into two or more parts in the width direction of the chip substrate and is continuous with each of the heat generating parts, The base side of the heat dissipation fin is separated into two or more parts in the width direction, and one heat dissipation section is located above each base side, and each base side is connected to each heat generating section via each current passing section, so that heat from each heat generating section is transferred from each base side to one heat dissipation section through each current passing section, and is then dissipated from that heat dissipation section to the outside of the chip substrate. A heater chip characterized by:

8. The chip substrate has two or more heat generating parts, a current passing part that increases the current density, and two or more heat dissipation fins, The two or more heat generating parts are separated in the width direction of the chip substrate, and generate heat by supplying power to pressurize and heat the conductors and electrodes, and the heat generating temperatures are different; The upper part of the current passing part is continuous with the power supply part of the chip substrate, and the lower part is separated into two or more parts in the width direction of the chip substrate and is continuous with each of the heat generating parts, Each of the two or more heat dissipation fins has a heat dissipation portion above its base side, and the base side of each is continuous with a respective heat generating portion via a respective current passing portion, so that heat from each heat generating portion is transferred from the base side of each heat dissipation fin to the heat dissipation portion of each heat dissipation fin through each current passing portion, and is then dissipated from each heat dissipation portion to the outside of the chip substrate. A heater chip characterized by:

9. The heater chip according to any one of claims 1 to 8, The outer periphery of the heat dissipation part of the heat dissipation fin is separated from the chip substrate. A heater chip characterized by:

10. The heater chip according to any one of claims 1 to 8, The heat dissipation part is covered with a material with good heat dissipation properties, or the surface area is made larger than that of a flat plate to enhance heat dissipation. A heater chip characterized by:

11. The heater chip according to any one of claims 1 to 8, Each heat generating part is provided with a temperature sensor, and the heat generating temperature of each heat generating part can be controlled based on the temperature detected by each temperature sensor. A heater chip characterized by:

12. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heating element of the heater chip, and each heating element applies pressure and heat to the conductor and electrode to heat-bond them together. After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the heater chip. A method for exothermic bonding of a conductor and an electrode using a heater chip.

13. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heat generating portion of the heater chip, and two or more conductors of the same or different diameters arranged on one electrode are simultaneously pressurized and heated by each heat generating portion to heat-bond them together; After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the heater chip. A method for exothermic bonding of a conductor and an electrode using a heater chip.

14. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heat generating portion of the heater chip, and each heat generating portion simultaneously pressurizes and heats the conductors of the same or different wire diameters that are arranged on each of the two or more electrodes, thereby heat-bonding them; After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the heater chip. A method for exothermic bonding of a conductor and an electrode using a heater chip.

15. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heating element of the heater chip, and each heating element applies pressure and heat to the conductor and electrode to heat-bond them together. After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the connecting portion of the heater chip and promote heat dissipation from the heat generating portion. A method for exothermic bonding of a conductor and an electrode using a heater chip.

16. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heat generating portion of the heater chip, and two or more conductors of the same or different diameters arranged on one electrode are simultaneously pressurized and heated by each heat generating portion to heat-bond them together; After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the heater chip and promote heat dissipation from the heat generating portion. A method for exothermic bonding of a conductor and an electrode using a heater chip.

17. A method for exothermic bonding an electrode and a conductor wired thereon by applying pressure and heat with a heater tip, The heater chip is the heater chip according to any one of claims 1 to 8, Power is supplied to the heater chip to heat each heat generating portion of the heater chip, and each heat generating portion simultaneously pressurizes and heats the conductors of the same or different wire diameters that are arranged on each of the two or more electrodes, thereby heat-bonding them; After the heat-generating bonding, the power supply to the heater chip is stopped to stop the heat generation of each heat-generating part, and when the temperature of each heat-generating part has dropped, the heater chip is separated from the heat-generating bonding part. At least after power supply is stopped, heat from the heat generating portion is dissipated from the heat dissipation fins to reduce heat transfer from the heat generating portion to the heater chip and promote heat dissipation from the heat generating portion. A method for exothermic bonding of a conductor and an electrode using a heater chip.

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