TWI768682B - Metal circuit pattern and method of producing metal circuit pettern - Google Patents

Abstract

The subject of this invention is to provide the technique which can manufacture a circuit board efficiently. The metal circuit pattern of the present invention is a metal circuit pattern for the manufacture of a circuit substrate in which a metal plate to form a circuit pattern is bonded to an insulating substrate; it is provided with: a plurality of independent metal sheets for forming the circuit pattern; and A carrier tape that can be pasted with a plurality of metal monoliths while maintaining a circuit pattern; and at least any side of the plurality of metal monoliths has a fracture surface and a shear surface, and further has a shear scar with the shear surface. Different friction marks.

Description

Metal circuit pattern and manufacturing method of metal circuit pattern

The present invention relates to a metal circuit pattern and a method for manufacturing the metal circuit pattern.

As a board|substrate for a power supply module, the circuit board which joined the metal plate to form a circuit pattern to an insulating board|substrate is widely used. For example, Patent Document 1 proposes a ceramic circuit board in which a copper plate is bonded to an alumina plate. Moreover, as an insulating substrate, there is a case where a high heat dissipation resin substrate containing a resin material and a thermal conductive filler is used. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 3-145748

(The problem that the invention intends to solve)

The objective of this invention is to provide the technique which can manufacture a circuit board efficiently. (Technical means to solve problems)

According to one aspect of the present invention, there is provided a metal circuit pattern, which is a metal circuit pattern for manufacturing a circuit substrate in which a metal plate for forming a circuit pattern is bonded to an insulating substrate; A plurality of metal monoliths; and a carrier tape that can be pasted with the plurality of metal monoliths while maintaining the above-mentioned circuit pattern; and at least any side surface of the plurality of metal monoliths has a broken surface and a shearing surface, Furthermore, it has friction marks different from the shearing marks on the above-mentioned shearing surface.

According to another aspect of the present invention, there is provided a method for manufacturing a metal circuit pattern, comprising: a method for manufacturing a metal circuit pattern for manufacturing a circuit substrate in which a metal plate is bonded to a highly heat-dissipating resin substrate comprising a resin material and a thermally conductive filler; There are: a punching step of punching a metal raw material plate to form a plurality of independent metal single sheets; and a sticking step of pasting the carrier tape on the above-mentioned plurality of metal single sheets; in the above-mentioned punching step, by punching The plurality of metal single pieces cut out are pushed back to the punching holes of the metal raw material plate, and friction marks are formed on the side surfaces of the plurality of metal single pieces; The plurality of metal single pieces are disassembled, and the carrier tape is pasted in a state where the circuit patterns of the plurality of metal single pieces are retained. (Compared to the efficacy of the prior art)

According to the present invention, a circuit board can be efficiently manufactured.

[Description of Embodiments of the Present Invention] <Results of research obtained by the inventors> First, the research results obtained by the present inventors will be described.

As a metal plate used for a circuit board, from the viewpoint of heat dissipation and electrical conductivity, for example, a copper plate is widely used. Moreover, as an insulating substrate used for a circuit board, a ceramic substrate or a high heat dissipation resin substrate is used. As a method of bonding a copper plate to a ceramic substrate, for example, a direct bonding method and an active metal method are known. The direct bonding method includes, for example, a method in which a copper plate is placed in contact with a ceramic substrate and heated to generate a eutectic liquid phase such as Cu-O, and then the eutectic liquid phase is cooled and solidified, so that the ceramic substrate and the eutectic liquid phase are cooled and solidified. Copper plates are directly bonded. On the other hand, the active metal method includes, for example, a method in which a ceramic substrate and a copper plate are joined via a solder filler metal layer containing an active metal such as Ti.

Moreover, as a method of forming a circuit pattern of a circuit board, for example, a method of forming a circuit pattern by punching a copper plate by pressing in advance, and a method of forming a circuit pattern by etching after the entire surface of the copper plate are joined are known.

In recent years, the increase in output of semiconductor elements using circuit boards has continued, and higher heat dissipation properties of the circuit boards have been required. Therefore, as a copper plate used for a circuit board, it is preferable to have a thickness of 0.5 mm or more, for example.

When the copper plate has a thickness of 0.5 mm or more, it is difficult to form a circuit pattern by etching. On the other hand, when the circuit pattern is formed by punching in advance, it is difficult to handle the individual metal pieces after punching. Specifically, for example, it is difficult to perform positioning when bonding a metal circuit pattern to an insulating substrate. Moreover, when forming a circuit pattern by a press process in advance, there exists a problem that a burr may generate|occur|produce.

The inventors of the present application have intensively studied the above-mentioned phenomenon. As a result, it was found that by adopting the push back method in the stamping step and sticking the metal single piece to the carrier tape while maintaining the circuit pattern, the handling of the independent metal single piece can be made easier, and Efficiently manufacture circuit boards. In addition, it was found that the occurrence of burrs can be suppressed.

The present invention has been completed based on the above-mentioned research results found by the present inventors. [Details of Embodiments of the Present Invention]

Next, an embodiment of the present invention will be described below with reference to the accompanying drawings. It should be noted that the present invention is not limited to these examples, but is disclosed by the scope of the patent application, and includes all modifications within the meaning and scope equivalent to the scope of the patent application.

<The first embodiment of the present invention> (1) Composition of metal circuit pattern The metal circuit pattern 10 of the present embodiment is used for a part of the constituent elements of the circuit board of the power module. A circuit board can be produced by bonding the metal circuit pattern 10 of the present embodiment to an insulating substrate. As the insulating substrate, for example, a ceramic substrate made of alumina or aluminum nitride, or a highly heat-dissipating resin substrate containing a resin material and a thermally conductive filler can be used. In addition, in this specification, the so-called high heat dissipation resin substrate includes not only rigid (hard) substrates but also flexible substrates, or generally referred to as heat dissipation insulating sheets, heat dissipation lubricants, heat dissipation tapes, and heat dissipation adhesives. Hereinafter, the structure of the metal circuit pattern 10 of this embodiment is demonstrated.

FIG. 1A is a plan view of the metal circuit pattern 10 of the present embodiment. FIG. 1B is a side view of the metal circuit pattern 10 of the present embodiment. FIG. 1C is an enlarged view of the side of the metal monolith 12 . As shown in FIG. 1A and FIG. 1B , the metal circuit pattern 10 of the present embodiment includes a carrier tape 11 and a plurality of metal single pieces 12 .

The carrier tape 11 is configured so that a plurality of metal monoliths 12 can be pasted with the circuit pattern held thereon. As such a carrier tape 11 , for example, a tape obtained by applying a synthetic resin-based adhesive to a plastic film such as PET (polyethylene terephthalate), polyester, and polypropylene can be used.

A plurality of metal single sheets 12 are independently pasted on the carrier tape 11 to form circuit patterns. As the material of the plurality of metal single pieces 12 , for example, copper or copper alloy can be used. The thickness of the plurality of metal single pieces 12 is preferably, for example, 0.5 mm or more and 4.0 mm or less. When the thickness of the plurality of metal single pieces 12 is less than 0.5 mm, there is a possibility that sufficient heat dissipation properties required for the power module substrate cannot be obtained. On the other hand, by setting the thickness of the plurality of metal single pieces 12 to be 0.5 mm or more, sufficient heat dissipation properties required for the power module substrate can be obtained. On the other hand, when the thickness of the plurality of metal single pieces 12 exceeds 4.0 mm, the productivity is deteriorated. On the other hand, by setting the thickness of the plurality of metal single pieces 12 to be 4.0 mm or less, the productivity can be improved. Furthermore, in consideration of the balance between heat dissipation and productivity, the thickness of the plurality of metal single pieces 12 is more preferably 0.7 mm or more and 3.0 mm or less.

In the metal circuit pattern 10 of the present embodiment, since the circuit pattern is held by the carrier tape 11 , the handling of the plurality of metal single pieces 12 can be easily performed. Specifically, for example, positioning when the metal circuit pattern 10 is to be bonded to an insulating substrate can be easily performed. Thereby, a circuit board can be manufactured efficiently.

Moreover, as shown in FIG. 1B , the side surfaces of the plurality of metal single pieces 12 have friction marks 13 . In addition, in this specification, a "rubbing mark" means the trace which a metal rubs against each other, for example. For example, the friction marks 13 extend along the thickness direction of the plurality of metal single sheets 12 and are interrupted at predetermined positions. Furthermore, not all the side surfaces of the plurality of metal sheets 12 necessarily have the friction marks 13 , and there may also be side surfaces without the friction marks 13 . At least one side surface of the plurality of metal single sheets 12 has friction marks 13 , and among the plurality of metal single sheets 12 of the metal circuit pattern 10 , preferably more than 50% of the metal single sheets 12 have friction marks 13 on their sides. More preferably, more than 70% of the metal sheets 12 have friction marks 13 on their sides, and more preferably more than 90% of the metal sheets 12 have friction marks 13 on their sides.

Here, in a general power supply module, the semiconductor element is soldered on the circuit board, and after the metal circuit pattern, the semiconductor element, and the external terminal are connected by bonding wires, in order to ensure the insulation, for example, a resin such as silicone is used. (hereinafter, referred to as sealing resin) to seal. Such a power module is also called a case module. When the metal circuit pattern 10 of the present embodiment is used in the case module as described above, since the side surfaces of the plurality of metal single pieces 12 have friction marks 13, the adhesion between the circuit board and the sealing resin can be improved. . Thereby, when vibration is applied to the case module, for example, the vibration of the circuit board can be suppressed. As a result, breakage of the bonding wire and the like can be suppressed, and the reliability of the semiconductor element can be improved.

In addition, when the metal circuit pattern 10 of the present embodiment is used in the above-mentioned case module, since the side surfaces of the plurality of metal single pieces 12 have friction marks 13, the solder on the side surfaces of the plurality of metal single pieces 12 Wetting will be reduced. Thereby, when the semiconductor element is to be soldered on the circuit board, for example, it is possible to reduce the risk that the excess solder overflows and flows out.

In the metal circuit pattern 10 of the present embodiment, as shown in FIG. 1B , the main surfaces 14 of the plurality of metal single pieces 12 on the side close to the friction marks 13 are attached to the carrier tape 11 . On the other hand, the main surfaces 15 of the plurality of metal single pieces 12 on the far side from the friction marks 13 are exposed. Further, as shown in FIG. 1C , the main surface 15 on the far side from the friction marks 13 is a so-called die roll surface having a smooth R (arc) shape in the peripheral portion. The maximum height Rz ₂ of the peripheral portion of the main surface 15 on the far side from the friction marks 13 is smaller than the maximum height Rz ₁ of the peripheral portion of the main surface 14 on the side of the friction marks 13 . In addition, the maximum height Rz is prescribed|regulated by JIS (Japanese Industrial Standard) B0601-2001. In addition, in this specification, the mold roll means the smooth R shape which arises in the fracture surface when a flat plate is sheared. In addition, the main surface on the side where the die roll occurs is referred to as a die roll surface.

As shown in FIG. 1C , the side surfaces of the plurality of metal single pieces 12 have broken surfaces 16 and sheared surfaces 17 . The broken surface 16 is a sharply uneven surface located on the main surface 14 side, and the shearing surface 17 is a smooth surface located on the main surface 15 side. Furthermore, not all the side surfaces of the plurality of metal sheets 12 necessarily have the fractured surface 16 and the sheared surface 17 , and there may be side surfaces without the fractured surface 16 and the sheared surface 17 . At least one side of the plurality of metal single pieces 12 has a broken surface 16 and a sheared surface 17. Among the plurality of metal single pieces 12 of the metal circuit pattern 10, preferably more than 50% of the metal single pieces 12 are. The side surface has a broken surface 16 and a shear surface 17, more preferably more than 70% of the side surface of the metal single piece 12 has a broken surface 16 and a shear surface 17, and more preferably more than 90% of the side surface of the metal single piece 12 It has a broken surface 16 and a sheared surface 17 .

As shown in FIG. 1C , flaws (hereinafter, referred to as shear flaws 19 ) generated by the shearing process may be formed in the thickness direction of the single metal piece 12 on the shear surface 17 , but this embodiment The friction marks 13 of the metal circuit pattern 10 of the form are different from such shear marks 19 . That is, the side surfaces of the plurality of metal single pieces 12 have friction marks 13 different from the shearing flaws 19 of the shearing surface 17 . Specifically, for example, the friction marks 13 are shorter in length than the shearing marks 19 . Compared with the shear scar 19 having approximately the same length as the thickness of the shear surface 17 , the friction scar 13 is shorter than the thickness of the shear surface 17 . Friction marks 13 are preferably shorter than half the thickness of shear surface 17 . Thereby, when the metal circuit pattern 10 is produced, the occurrence of burrs is easily suppressed.

In the metal circuit pattern 10 of the present embodiment, the friction marks 13 are preferably formed near the boundary 18 between the fracture surface 16 and the shear surface 17 , more preferably on the shear surface 17 side from the boundary 18 . On the side surfaces of the plurality of metal single pieces 12 , since the surface roughness decreases sharply from the fractured surface 16 to the sheared surface 17 , the vicinity of the boundary 18 is a position where the adhesion between the circuit board and the sealing resin tends to decrease. By forming the rubbing marks 13 at such positions, it is possible to suppress the decrease in the surface roughness of the side surfaces of the plurality of metal single pieces 12, and to improve the adhesion between the circuit board and the sealing resin.

When bonding the metal circuit pattern 10 of the present embodiment to an insulating substrate, by bonding the main surface 15 farther from the rubbing mark 13 to the insulating substrate, the bonding can be performed while the circuit pattern is retained. That is, by bonding the main surface 15 not attached to the carrier tape 11 side to the insulating substrate, the carrier tape 11 can hold the circuit pattern for bonding. In this case, since the peripheral edge portion of the main surface 15 on the far side from the friction marks 13 is the die roll surface, the contact surface between the main surface 15 and the insulating substrate becomes flat. That is, since the peripheral portion of the main surface 15 farther from the friction marks 13 does not have protrusions or the like that hinder the contact with the insulating substrate, the contact surface with the insulating substrate can be made flat. Thereby, for example, when the metal circuit pattern 10 is bonded to the ceramic substrate, the bondability between the metal circuit pattern 10 and the ceramic substrate can be improved.

Moreover, when bonding the main surface 15 farther from the friction mark 13 to the ceramic substrate as described above, the semiconductor element is soldered to the main surface 14 on the side close to the friction mark 13 . In this case, since the friction marks 13 are present near the surface where the soldering is performed, the risk of overflowing and flowing out of the remaining solder can be reduced.

In the case of bonding the metal circuit pattern 10 of the present embodiment to the high heat dissipation resin substrate, it is preferable to bond the main surface of at least one of the plurality of metal sheets 12 (preferably not to the side of the carrier tape 11 ). The main surface of , in this embodiment, the main surface 15) is set as a roughened surface. In this case, by bonding the roughened surface to the high heat dissipation resin substrate, the bondability between the metal circuit pattern 10 and the high heat dissipation resin substrate can be improved. In addition, the arithmetic mean roughness Ra (JIS (Japanese Industrial Standard) B0601-2001) of the roughened surface is preferably 0.15 μm or more and 5 μm or less.

(2) Manufacturing method of metal circuit pattern Next, the manufacturing method of the metal circuit pattern 10 of this embodiment is demonstrated.

FIG. 2 is a flowchart showing an example of a method of manufacturing the metal circuit pattern 10 of the present embodiment. The manufacturing method of the metal circuit pattern 10 of this embodiment has, for example, a roughening process step S1, a punching step S2, a sticking step S3, and an inspection and packaging step S4.

(roughening process step S1) In roughening processing step S1, roughening processing is performed on the main surface of at least one of the metal raw material sheets 20. As the metal raw material plate 20 , a metal material having predetermined thermal conductivity and predetermined electrical conductivity corresponding to the characteristics of the semiconductor element to be mounted on the circuit board, such as copper or copper alloy, can be used. In addition, in order to make the metal circuit pattern 10 have predetermined properties such as strength and heat resistance, a predetermined amount of additive elements such as iron, zinc, phosphorus, tin, and nickel may be added to the above-mentioned metal material.

In the roughening treatment step S1, for example, a main surface of at least one of the metal raw material sheets 20 is subjected to a roughening treatment using a sulfuric acid-based etching solution to form a roughened surface. In the roughening treatment step S1, it is preferable to perform the roughening treatment so that the arithmetic mean roughness Ra of the roughened surface becomes 0.15 μm or more and 5 μm or less. Thereby, by bonding the roughened surface to the high heat dissipation resin substrate, the bondability between the metal circuit pattern 10 and the high heat dissipation resin substrate can be improved. Furthermore, the roughening process step S1 may be omitted.

(pressing step S2) In the punching step S2, the metal raw material plate 20 is punched to form a plurality of independent metal sheets 12 to be formed with circuit patterns.

3A, 3B and 3C are schematic cross-sectional views showing a part of the pressing step S2. In the punching step S2, first, the metal raw material plate 20 is fed into the punching machine. As shown in FIG. 3A , the punching machine is provided with, for example, a die 21 , a punch 22 , a knock out 23 , and a stripper 24 .

The die 21 has a forming hole 25 for forming the metal raw material plate 20 into the shape of a predetermined circuit pattern. Then, after the metal raw material plate 20 is sent between the die 21 and the punch 22, as shown in FIG. 3B, the punch 22 is lowered, and the ejector 23 in the forming hole 25 is pressed down, while the metal raw material is removed from the metal raw material. The plate 20 punches a plurality of metal single pieces 12 into the forming holes 25 . At this time, the mold release member 24 functions as a plate pressing member that presses against the metal raw material plate 20 . When the metal single piece 12 is punched out, a broken surface 16 and a sheared surface 17 are formed on the side surface of the metal single piece 12 . The breaking surface 16 is formed on the side of the punch 22 , and the shearing surface 17 is formed on the side of the ejector 23 .

After the plurality of metal sheets 12 are punched out from the metal raw material plate 20, as shown in FIG. 3C, the ejector 23 is raised, and the punch 22 is pushed up to push the punched out plurality of metal sheets The original metal sheet 20 of the sheet 12 is pushed back into the punched hole 26 . Such a shaping method is called a push back method. By adopting the push-back method, the occurrence of burrs can be suppressed. In addition, the next step can be performed in a state in which the circuit pattern is held.

In addition, when the punched metal single pieces 12 are to be pushed back into the punching holes 26 , for example, by appropriately controlling the gap between the punching die 21 and the punching head 22 , the punching holes of the metal raw material plate 20 can be cut. The inner peripheral surface of 26 rubs against the outer peripheral surface of the plurality of metal single pieces 12 punched out. Thereby, the friction marks 13 can be formed on the side surfaces of the plurality of metal single sheets 12 . More specifically, the friction marks 13 may be formed on the side surfaces of the plurality of metal single sheets 12 in the region close to the punch 22 . The friction marks 13 are formed along the punching direction of the punching machine, that is, along the thickness direction of the plurality of metal single sheets 12 .

The friction marks 13 are preferably formed to be shorter than half the thickness of the shear surface 17 . By forming the friction marks 13 in this way, the occurrence of burrs can be suppressed. In addition, the friction marks 13 are preferably formed near the boundary 18 between the broken surfaces 16 and the shearing surfaces 17 of the side surfaces of the plurality of metal sheets 12 , and more preferably formed on the side of the shearing surface 17 from the boundary 18 . Thereby, the adhesiveness of a circuit board and sealing resin can be improved.

Furthermore, when the plurality of metal single pieces 12 punched out are to be pushed back into the punching hole 26 , for example, the plurality of metal single pieces 12 are pushed back so that a part of the thickness of the plurality of metal single pieces 12 is fitted into the punching hole 26 . The friction marks 13 are formed so as to be interrupted at predetermined positions by pushing back so that a part of the thickness of the plurality of metal single sheets 12 is fitted into the punching holes 26 .

The peripheral edge portion of the main surface 14 of the plurality of single metal pieces 12 on the side of the friction mark 13 (the side of the punch 22 ) is an area where burrs are likely to occur. On the other hand, the main surface 15 of the plurality of metal sheets 12 on the far side (the ejector 23 side) from the friction marks 13 is a so-called die roll surface having a smooth R-shape at the peripheral edge. In the punching step S2, plural numbers are formed in such a way that the maximum height Rz ₂ of the peripheral edge portion of the main surface 15 on the far side of the friction mark 13 is smaller than the maximum height Rz ₁ of the peripheral edge portion of the main surface 14 on the side of the friction mark 13. A single metal sheet 12.

Furthermore, it is preferable to stop the descending of the punch 22 at the stage when the front end of the punch 22 does not reach the opening end of the forming hole 25 of the punch 21 when punching out a plurality of single metal pieces 12 from the metal raw material plate 20, and to stop the lowering of the punch 22 at the stage when the front end of the punch 22 does not reach the opening end of the forming hole 25 of the punch 21. Start to push back in the state. Thereby, the occurrence of burrs can be suppressed.

(Paste step S3) In the pasting step S3 , the carrier tape 11 is pasted to the plurality of metal single sheets 12 . First, the plurality of metal single pieces 12 are fed into the sticking apparatus in a state in which they are fitted into the punched holes 26 of the metal raw material plate 20 in a state in which the circuit patterns are retained.

4A and 4B are schematic cross-sectional views showing a part of the sticking step S3. As shown in FIGS. 4A and 4B , for example, the sticking device is provided with a rod 30 , a first head 31 , and a second head 32 .

As shown in FIG. 4A , the rod 30 is provided with a recess 33 for holding the plurality of metal single pieces 12 . The position of the rod 30 is adjusted so that the concave portion 33 is positioned below the plurality of metal single pieces 12 . After that, the first head 31 is lowered to remove the plurality of metal single pieces 12 fitted in the punching holes 26 . The disassembled plurality of metal single pieces 12 can be moved by the concave portion 33 of the rod 30 while maintaining the circuit pattern.

Next, the rod 30 is moved below the second head 32 , and the carrier tape 11 is fed out between the second head 32 and the rod 30 . After that, the second head 32 is lowered, and the carrier tape 11 is punched into a predetermined size, and is attached to the plurality of metal single pieces 12 . That is, the carrier tape 11 is pasted in a state in which the circuit patterns of the plurality of metal single pieces 12 are held. Thereby, the manipulation of the plurality of metal monoliths 12 can be easily performed. As a result, the circuit board can be efficiently manufactured.

In addition, as described above, the peripheral edge portion of the main surface 14 of the plurality of metal single pieces 12 on the side close to the friction marks 13 is an area where burrs are likely to occur. When burrs occur on the periphery of the main surface 14 of the plurality of metal sheets 12 on the side close to the friction marks 13, the burrs can be flattened by adjusting the load of the second head 32 when the carrier tape 11 is to be pasted. make it smaller.

In the sticking step S3 , the carrier tape 11 is sticked to the main surfaces 14 of the plurality of metal sheets 12 on the side close to the friction marks 13 . Thereby, the main surface 15 which is not adhered to the carrier tape 11 side can be joined to the insulating substrate in a state in which the circuit pattern is held. In this case, since the main surface 15 on the far side from the friction marks 13 is the die roll surface, the contact surface between the main surface 15 and the insulating substrate becomes flat. Thereby, for example, when the metal circuit pattern 10 is bonded to the ceramic substrate, the bondability between the metal circuit pattern 10 and the ceramic substrate can be improved.

(Inspecting and packing step S4) In the inspection and packaging step S4, first, the appearance inspection of the metal circuit pattern 10 to which the carrier tape 11 is attached is performed. In the appearance inspection, for example, the metal circuit pattern 10 is inspected for the presence or absence of scratches, deformation, dents, or the like. Next, packaging of the metal circuit pattern 10 is performed. Packaging of the metal circuit pattern 10 is performed by storing the metal circuit pattern 10 judged to be a good product in the appearance inspection, for example, in a container for packaging every predetermined number.

Through the above steps, the finished metal circuit pattern 10 can be manufactured.

In the manufacturing method of the metal circuit pattern 10 of the present embodiment, as described above, the push-back method is used in the punching step S2, and the circuit pattern of the plurality of metal single pieces 12 is maintained in the sticking step S3. By pasting the carrier tape 11 , the handling of the plurality of metal single sheets 12 can be easily performed. As a result, the circuit board can be efficiently manufactured.

Furthermore, in the method of manufacturing the metal circuit pattern 10 of the present embodiment, as described above, by appropriately controlling the gap between the die 21 and the punch 22 in the punching step S2, it is possible to form on the side surfaces of the plurality of metal single pieces 12 Friction marks 13. Thereby, the adhesiveness of a circuit board and a sealing resin can be improved, for example.

(3) Effects of the present embodiment According to this embodiment, one or a plurality of effects shown below can be exhibited.

(a) In the metal circuit pattern 10 of the present embodiment, since the circuit pattern is held by the carrier tape 11 , the handling of the plurality of metal single pieces 12 can be easily performed. Specifically, for example, positioning when the insulating substrate is to be bonded to the metal circuit pattern 10 can be easily performed.

Here, in the conventional circuit board, when the metal circuit pattern is to be bonded to the insulating board, for example, a plate-shaped jig punched into the shape of the circuit pattern must be placed on the insulating board, and one jig must be placed on the insulating board. The metal monoliths are arranged individually, so workability is poor. In addition, there is a possibility that the accuracy of the circuit pattern may be lowered due to vibration when the jig is removed or when it is transported to a heating furnace. Moreover, when forming a metal circuit pattern by press work, there exists a problem that a burr may generate|occur|produce.

On the other hand, when the metal circuit pattern 10 of the present embodiment is to be bonded to an insulating substrate, since the metal circuit pattern 10 can be individually laminated on the insulating substrate for each carrier tape 11 , compared with the conventional method, the Workability can be greatly improved. In addition, the accuracy of the circuit pattern can be improved. In addition, since the push-back method is adopted, the occurrence of burrs can be suppressed. Therefore, the circuit board can be efficiently manufactured.

(b) When the metal circuit pattern 10 of the present embodiment is used in the case module as described above, since the side surfaces of the plurality of metal single pieces 12 have friction marks 13, the circuit board and the sealing resin can be separated from each other. Improved adhesion. Thereby, when vibration is applied to the case module, for example, the vibration of the circuit board can be suppressed. As a result, breakage of the bonding wire and the like can be suppressed, and the reliability of the semiconductor element can be improved.

(c) When the metal circuit pattern 10 of the present embodiment is used in the case module as described above, since the side surfaces of the plurality of metal single pieces 12 have friction marks 13, the side surfaces of the plurality of metal single pieces 12 have friction marks 13. The solder wettability will be reduced. Thereby, for example, when the semiconductor element is to be soldered on the circuit board, it is possible to reduce the risk that the remaining solder overflows and flows out.

(d) In the metal circuit pattern 10 of the present embodiment, the friction marks 13 are shorter in length than the shearing scratches 19 , and preferably shorter than half the thickness of the shearing surface 17 . Thereby, the occurrence of burrs can be suppressed.

(e) In the metal circuit pattern 10 of the present embodiment, the friction marks 13 are preferably formed in the vicinity of the boundary 18 between the broken surface 16 and the shear surface 17 , and more preferably formed on the shear surface from the boundary 18 17 sides. Thereby, the change of the surface roughness of the side surface of the plurality of metal single pieces 12 can be made gentle, and the adhesiveness of a circuit board and a sealing resin can be improved.

(f) When the metal circuit pattern 10 of the present embodiment is to be bonded to an insulating substrate, by bonding the main surface 15 farther from the friction mark 13 to the insulating substrate, the circuit pattern can be maintained in a state Join below. That is, by bonding the main surface 15 not attached to the carrier tape 11 side to the insulating substrate, the carrier tape 11 can hold the circuit pattern for bonding. Also, in this case, since the main surface 15 on the far side from the friction marks 13 is a rounded surface, the contact surface between the main surface 15 and the ceramic substrate becomes flat. Thereby, when, for example, the metal circuit pattern 10 is to be bonded to the ceramic substrate, the bondability between the metal circuit pattern 10 and the ceramic substrate can be improved. Therefore, the metal circuit pattern 10 of the present embodiment can be suitably used for, for example, a ceramic circuit board produced by a direct bonding method in which a copper plate is directly bonded to a ceramic board.

(g) When the metal circuit pattern 10 of the present embodiment is to be bonded to a high heat dissipation resin substrate, it is preferable to bond at least one main surface (preferably not to the carrier tape) of the plurality of metal single sheets 12 The main surface on the 11 side is the main surface 15) in the present embodiment as a roughened surface. In this case, by bonding the roughened surface to the high heat dissipation resin substrate, the bondability between the metal circuit pattern 10 and the high heat dissipation resin substrate can be improved. Therefore, the metal circuit pattern 10 of the present embodiment can also be suitably used for a circuit board in which a metal plate is bonded to a highly heat-dissipating resin board.

(h) In the manufacturing method of the metal circuit pattern 10 of the present embodiment, by adopting the push-back method in the punching step S2, and in the sticking step S3, the circuit patterns of the plurality of metal single pieces 12 are maintained in the state of sticking The carrier tape 11 can easily handle a plurality of metal sheets 12 . As a result, the circuit board can be efficiently manufactured.

(i) In the manufacturing method of the metal circuit pattern 10 of the present embodiment, by appropriately controlling the gap between the die 21 and the punch 22 in the punching step S2 , the friction marks 13 can be formed on the side surfaces of the plurality of metal sheets 12 . Thereby, the adhesiveness of a circuit board and a sealing resin can be improved, for example.

(4) Modification of the first embodiment The above-described embodiment can be changed as necessary, as in the following modifications. Hereinafter, only the elements different from the above-mentioned embodiments will be described, and the elements that are substantially the same as the elements described in the above-mentioned embodiments will be denoted by the same reference numerals, and the description thereof will be omitted.

FIG. 5A is a plan view of the metal circuit pattern 40 of this modification. FIG. 5B is a longitudinal cross-sectional view of the metal circuit pattern 40 of this modification. As shown in FIGS. 5A and 5B , the metal circuit pattern 40 of this modification is different from the metal circuit pattern 10 of the first embodiment in the portion having the metal outer frame 41 .

The metal frame 41 is provided in order to protect the circuit pattern, and is, for example, pasted to the outer peripheral portion of the carrier tape 11 . The metal frame 41 can be detached from the carrier tape 11 at any timing before the metal circuit pattern 40 is bonded to the insulating substrate.

Since the metal circuit pattern 40 of this modification has the metal outer frame 41 , the manipulation of the plurality of metal single pieces 12 can be easily performed. In addition, for example, the circuit pattern can be protected from vibration during packaging or transportation, and the accuracy of the circuit pattern can be improved.

<Second embodiment of the present invention> Next, the second embodiment of the present invention will be described focusing on the differences from the first embodiment.

FIG. 6A is a plan view of the metal circuit pattern 50 of the present embodiment. FIG. 6B is a side view of the metal circuit pattern 50 of the present embodiment. As shown in FIG. 6B , in the metal circuit pattern 50 of the present embodiment, the main surfaces 15 of the plurality of metal single pieces 12 on the far side from the friction marks 13 are pasted to the carrier tape 11 . That is, the surface adhered to the carrier tape 11 is opposite to that of the first embodiment.

The metal circuit pattern 50 of this embodiment can be manufactured by, for example, disposing the carrier tape 11 on the rod 30 in advance when removing the plurality of metal pieces 12 fitted in the punching holes 26 in the pasting step S3 .

When the metal circuit pattern 50 of the present embodiment is to be bonded to an insulating substrate, the bonding can be performed with the circuit pattern retained by bonding the main surface 14 on the side close to the rubbing marks 13 to the insulating substrate. That is, by bonding the main surface 14 that is not attached to the carrier tape 11 side to the insulating substrate, the carrier tape 11 can hold the circuit pattern for bonding. In this case, since the peripheral portion of the main surface 15 farther from the friction marks 13 is a rounded surface, when the semiconductor element is mounted on the main surface 15, the risk of damage to the semiconductor element can be reduced.

In addition, the peripheral edge portion of the main surface 14 on the side of the friction marks 13 is an area where burrs are likely to occur. When the metal circuit pattern 50 of the present embodiment is used in a ceramic circuit substrate produced by, for example, an active metal method in which a copper plate is bonded to a ceramic substrate through a solder filler metal layer, the burrs on the peripheral portion of the main surface 14 may be mixed with Solder filler metal layers are in contact or close to each other. Thereby, the burr becomes a wall, and the seepage of the solder filler metal toward the surface of the circuit pattern can be suppressed. Therefore, the metal circuit pattern 50 of this embodiment can be suitably used for, for example, a ceramic circuit board produced by an active metal method.

Furthermore, when the metal circuit pattern 50 of this embodiment is to be bonded to a high heat dissipation resin substrate, the burrs of the peripheral portion of the main surface 14 are brought into contact with the high heat dissipation resin substrate, thereby exhibiting an anchor effect. Thereby, the bondability between the metal circuit pattern 10 and the high heat dissipation resin substrate can be improved. Therefore, the metal circuit pattern 10 of the present embodiment can also be suitably used for a circuit board in which a metal plate is bonded to a highly heat-dissipating resin board.

<Other Embodiments of the Present Invention> Although the embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

For example, in the above-mentioned embodiment, although in the punching step S2, when the punched out plurality of metal single pieces 12 are to be pushed back into the punching hole 26, the plurality of metal single pieces 12 are separated by The case of pushing back so that a part of the thickness is fitted into the punched hole 26 will be described, but the entire thickness of the plurality of metal pieces 12 may be pushed back so that the entire thickness of the plurality of metal pieces 12 is fitted into the punched hole 26 .

For example, in the above-described embodiment, in the punching step S2, when a plurality of metal pieces 12 are to be punched from the metal raw material sheet 20, the front end of the punch 22 does not reach the forming hole 25 of the punch 21. At the stage of the open end, the lowering of the punch 22 is stopped and the push-back is started in this state. However, the push-back may be started after the plurality of metal single pieces 12 are completely punched out.

<Preferable aspect of the present invention> Hereinafter, preferred aspects of the present invention will be described.

(Record 1) According to an aspect of the present invention, a metal circuit pattern can be provided, which is a metal circuit pattern for manufacturing a circuit substrate in which a metal plate for forming a circuit pattern is bonded to an insulating substrate; A plurality of metal monoliths; and a carrier tape that can be pasted to the above-mentioned plurality of metal monoliths in a state where the above-mentioned circuit pattern is maintained; , and further has friction marks different from the shear marks of the above-mentioned shearing surface.

(Record 2) The metal circuit pattern according to description 1, wherein the friction marks are shorter in length than the shearing marks. Preferably, the friction marks are shorter in length than half the thickness of the shear marks.

(Record 3) The metal circuit pattern according to the description 1 or 2, wherein the friction marks are formed in the vicinity of the boundary between the broken surfaces and the sheared surfaces of the plurality of metal single pieces. It is preferable that the said friction mark is formed in the said shearing surface side from the said boundary.

(Record 4) The metal circuit pattern according to any one of descriptions 1 to 3, wherein the insulating substrate is a highly heat-dissipating resin substrate containing a resin material and a thermally conductive filler.

(Record 5) The metal circuit pattern according to description 4, wherein at least one main surface of the plurality of metal single pieces is a roughened surface. Preferably, the main surface of the plurality of metal single sheets that is not adhered to the carrier tape side is a roughened surface. Preferably, the arithmetic mean roughness Ra of the roughened surface is 0.15 μm or more and 5 μm or less.

(Record 6) The metal circuit pattern according to any one of descriptions 1 to 5, wherein the main surfaces of the plurality of metal single pieces on the side close to the friction marks are adhered to the carrier tape.

(Record 7) The metal circuit pattern according to any one of descriptions 1 to 5, wherein the main surfaces of the plurality of metal single pieces that are farther from the friction marks are adhered to the carrier tape.

(Record 8) The metal circuit pattern according to any one of descriptions 1 to 7, wherein the friction marks extend along the thickness direction of the plurality of metal single pieces.

(Record 9) The metal circuit pattern according to any one of descriptions 1 to 8, wherein the friction marks are interrupted at predetermined positions.

(Record 10) The metal circuit pattern according to any one of descriptions 1 to 9, wherein the plurality of metal single pieces are made of copper or a copper alloy, and have a thickness of 0.5 mm or more and 4.0 mm or less. Preferably, the thickness of the plurality of metal single pieces is 0.7 mm or more and 3.0 mm or less.

(Record 11) The metal circuit pattern according to any one of descriptions 1 to 10, further comprising a metal outer frame attached to the outer peripheral portion of the carrier tape.

(Record 12) According to another aspect of the present invention, there can be provided a method for manufacturing a metal circuit pattern, which is a method for manufacturing a metal circuit pattern for manufacturing a circuit substrate in which a metal plate is bonded to a highly heat-dissipating resin substrate comprising a resin material and a thermal conductive filler; It is provided with: a punching step of punching a metal raw material plate to form a plurality of independent metal single sheets; and a pasting step of pasting the carrier tape on the plurality of metal single sheets; in the above-mentioned punching step, by The plurality of metal single sheets that have been punched out are pushed back into the punching holes of the metal raw material plate, and friction marks are formed on the side surfaces of the plurality of metal single sheets; The above-mentioned plurality of metal single pieces are disassembled by cutting holes, and the above-mentioned carrier tape is pasted in a state where the circuit patterns of the above-mentioned plurality of metal single pieces are maintained.

(Record 13) The method for producing a metal circuit pattern according to description 12, further comprising a roughening treatment step of roughening at least one main surface of the metal raw material sheet.

10: Metal circuit pattern 11 : Carrier tape 12: Metal Monolithic 13: Friction marks 14: Main side 15: Main side 16: Broken Section 17: Shear section 18: Junction 19: Cut Scars 20: Metal raw material board 21: Die 22: Punch 23: ejector 24: Release parts 25: Forming holes 26: Punching holes 30: Rod 31: Head 1 32: Head 2 33: Recess 40: Metal circuit pattern 41: Metal frame 50: Metal circuit pattern S1: Roughening treatment step S2: Stamping step S3: Paste Step S4: Inspection and packaging steps

FIG. 1A is a plan view of the metal circuit pattern 10 according to the first embodiment of the present invention. FIG. 1B is a side view of the metal circuit pattern 10 according to the first embodiment of the present invention. FIG. 1C is an enlarged view of the side surface of the metal single piece 12 according to the first embodiment of the present invention. FIG. 2 is a flowchart showing an example of a method of manufacturing the metal circuit pattern 10 according to the first embodiment of the present invention. 3A is a schematic cross-sectional view showing a part of the pressing step S2 in the first embodiment of the present invention. 3B is a schematic cross-sectional view showing a part of the pressing step S2 in the first embodiment of the present invention. 3C is a schematic cross-sectional view showing a part of the pressing step S2 in the first embodiment of the present invention. 4A is a schematic cross-sectional view showing a part of the sticking step S3 in the first embodiment of the present invention. 4B is a schematic cross-sectional view showing a part of the sticking step S3 in the first embodiment of the present invention. 5A is a plan view of a metal circuit pattern 40 according to a modification of the first embodiment of the present invention. 5B is a vertical cross-sectional view of the metal circuit pattern 40 according to a modification of the first embodiment of the present invention. FIG. 6A is a plan view of the metal circuit pattern 50 according to the second embodiment of the present invention. FIG. 6B is a side view of the metal circuit pattern 50 according to the second embodiment of the present invention.

10: Metal circuit pattern 11 : Carrier tape 12: Metal Monolithic 13: Friction marks 14: Main side 15: Main side 16: Broken Section 17: Shear section 18: Junction 19: Cut Scars

Claims (8)

A metal circuit pattern, which is a metal circuit pattern for the manufacture of a circuit substrate in which a metal plate to form a circuit pattern is bonded to an insulating substrate; it is provided with: a plurality of independent metal sheets for forming the circuit pattern; and A carrier tape that can be used for the above-mentioned plurality of metal single sheets to be pasted under the state of maintaining the above-mentioned circuit pattern; and at least any side surface of the above-mentioned plurality of metal single-pieces has a broken surface and a shearing surface, and further has the above-mentioned shearing surface. For friction marks with different shearing marks, the friction marks are shorter in length than the shearing marks. A metal circuit pattern, which is a metal circuit pattern for the manufacture of a circuit substrate in which a metal plate to form a circuit pattern is bonded to an insulating substrate; it is provided with: a plurality of independent metal sheets for forming the circuit pattern; and A carrier tape that can be used for the above-mentioned plurality of metal single sheets to be pasted under the state of maintaining the above-mentioned circuit pattern; and at least any side surface of the above-mentioned plurality of metal single-pieces has a broken surface and a shearing surface, and further has the above-mentioned shearing surface. As for the friction marks different from the shearing marks, the friction marks are formed in the vicinity of the boundary between the fracture surface and the shearing surface. The metal circuit pattern of claim 1 or 2, wherein the insulating substrate is a highly heat-dissipating resin substrate comprising a resin material and a thermally conductive filler. The metal circuit pattern of claim 3, wherein at least one main surface of the plurality of metal monoliths is a roughened surface. The metal circuit pattern of claim 1 or 2, wherein, The main surfaces of the plurality of metal single sheets on the side close to the friction marks are adhered to the carrier tape. The metal circuit pattern of claim 1 or 2, wherein the main surfaces of the plurality of metal single sheets on the far side from the friction marks are attached to the carrier tape. A method for manufacturing a metal circuit pattern, which is a method for manufacturing a metal circuit pattern for manufacturing a circuit substrate in which a metal plate is bonded to a highly heat-dissipating resin substrate comprising a resin material and a thermal conductive filler; the method includes: punching a metal raw material plate The punching step of cutting to form a plurality of independent metal single sheets; and the sticking step of pasting the carrier tape to the above-mentioned plurality of metal single sheets; in the above-mentioned punching step, by punching out the above-mentioned plurality of metal sheets The sheet is pushed back into the punching holes of the metal raw material plate, and friction marks are formed on the side surfaces of the plurality of metal single sheets; in the above-mentioned sticking step, the plurality of metal single sheets are affixed from the punching holes of the metal raw material plate. It is disassembled, and the above-mentioned carrier tape is pasted in the state that the circuit patterns of the above-mentioned plural metal single sheets are kept. The method for producing a metal circuit pattern according to claim 7, further comprising a roughening treatment step of roughening at least one main surface of the metal raw material plate.

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