JP5669495B2 - Resin-encapsulated metal component, lead frame used therefor, and method of manufacturing metal component - Google Patents

Description

  The present invention relates to a resin-encapsulated metal part such as a lead frame used in a semiconductor package or battery such as a memory, logic, custom LSI, power device, LED, etc., a lead frame used therefor, and a method for manufacturing the metal part.

  As electronic components, for example, semiconductor packages such as memory, logic, transistors, diodes, and LEDs are widely used. In recent electronic components, demand for LEDs for illumination and display and power devices for automobiles is increasing, and semiconductor packages used for these are becoming smaller. As for batteries, demand for lithium ion batteries for automobiles and personal computers is increasing, and in the case of lithium ion batteries, miniaturization and high output are rapidly progressing as in the case of semiconductor packages.

  In semiconductor packages that are becoming increasingly smaller, resin sealing is used to protect the semiconductor devices. However, the area of the interface between the metal terminals (lead frame) that take out the electrodes and mount the semiconductor devices and the resin is reduced by downsizing of the packages. It is getting smaller and smaller.

  For this reason, there is a possibility that the semiconductor device may be corroded or short-circuited due to the ingress of moisture from the interface between the resin and the metal terminal, and it is strongly desired to take preventive measures from the viewpoint of reliability.

  In lithium ion batteries, the lead-out port of the electrode lead terminal (lead frame) is sealed with an adhesive or resin to prevent leakage of electrolyte and intrusion of outside air. There is a risk of leakage of electrolyte or intrusion of outside air due to the narrowing of the size, and it is desired to take preventive measures.

  In light of these recent situations, improvement of the adhesion between resin-encapsulated metal parts such as lead frames and resin for the purpose of ensuring reliability has become a major issue. There are currently two developments in methods for improving the adhesion between metal parts and resins. One is to improve the adhesiveness of the resin, and the second is a method for roughening the metal surface.

  In order to improve the adhesiveness of the resin, attempts have been made to improve the fluidity of thermoplastic PPS resins and LCP resins and to modify the chemical resins.

  On the other hand, a chemical roughening treatment method is known as a metal surface roughening treatment method. As the chemical roughening treatment method, there is a method in which the surface of the metal is melted and roughened, or a method in which the surface of the metal is roughened as described in Patent Document 1 (Japanese Patent Laid-Open No. 2005-353919). is there. In either case, the area of the contact interface between the resin and the metal can be increased, and the adhesion strength (peeling strength) can be increased by the anchor effect (throwing effect).

  In the chemical dissolution method, for example, a special chemical that can form fine irregularities on the surface of aluminum is used. In the plating roughening method, rough plating is deposited on the surface by electroplating. This chemical roughening method has the feature that it can form fine irregularities of several μm depending on the selection of the roughening solution, but it requires a special treatment tank because of the use of chemicals, and it is further roughened by electroplating. Then, in order to use a pretreatment liquid and a plating solution, a plating apparatus is required.

  In addition, such chemical roughening treatment methods need to take measures against environmental pollution in the treatment of exhaust effluent and cleaning, and there is a concern that the working environment may be deteriorated.

  In addition, there is a mechanical method for the roughening treatment. For example, in Patent Document 2 (Japanese Patent Application Laid-Open No. 2001-225346), in a method of manufacturing a resin composite molded article in which a metal part is inserted, a surface of the metal part is previously coated with steel. A blasting method in which a hard fine powder such as glass or glass is blown to roughen is well known. This method is actually used for the purpose of improving the adhesion to paints by treating the surface of large machined parts and structures with a matte finish, but it is not suitable for small products and is partially rough. Cannot be processed. Semiconductor packages and lithium ion batteries are small in size and require roughening treatment only at the portions that come into contact with the resin.

  For example, in a semiconductor package, when the portion other than the interface with the sealing resin in the lead frame is roughened, the solderability of the portion where the lead frame is soldered is hindered. Moreover, in the LED package for illumination, there exists a problem that a reflectance falls besides solderability. In a lithium ion battery, a lead frame for an electrode is drawn out from a battery cap, and the interface between the cap and the metal electrode is sealed with an adhesive or a resin. In this case as well, it is necessary to roughen only the interface with the resin. When other portions of the metal electrode and the resin interface are roughened, there is a problem that the contact electric resistance increases, which is not preferable. Since the above-mentioned chemical roughening treatment method is also an immersion method, the partial roughening treatment is very difficult and has the same problems as the mechanical treatment method.

  As described above, there is an ever-increasing demand for improved reliability of semiconductor packages and lithium-ion batteries, and there is an urgent need to improve the adhesion between metal parts and resin. The reality is that there is no way to get it.

JP-A-2005-353919 JP 2001-225346 A

  The object of the present invention is to enable a new mechanical roughening process to replace a conventional chemical roughening process or a mechanical roughening process, and to perform a partial roughening process in a short time. In the region where the area of the interface adhesion to the resin of the method and the metal part for resin sealing obtained thereby is reduced, sufficient adhesion and adhesion are ensured, and the sealing property and peel strength are excellent, and other parts It is an object of the present invention to provide a resin-encapsulated metal part and a lead frame that do not interfere with solder connection, electrical connection, and other functionality.

In order to achieve the above object, the present invention basically proposes the following metal pressing method, resin-encapsulated metal part, and lead frame.
(1) In a method of manufacturing a metal part by metal pressing,
A step of forming a pressing rough surface by press transfer using a punch and die of a super hard die on a part of the front and back surfaces of a metal plate material to be a workpiece;
Before or after the pressing rough surface forming step, the metal plate material is punched to obtain the metal part, and the metal part is subjected to punching of fine groove rows on the plate thickness side surface intersecting with the pressing rough surface. A method of manufacturing a metal part comprising a step of forming a surface. Alternatively, in addition to the above-described steps, after forming the groove row by the punching process, a metal part manufacturing method for forming a fine rough surface at a satin level by using a side surface punch on the surface (plate thickness side surface) of the groove row .

Preferably, the punch and die used for forming the press-processed rough surface are formed on the first uneven surface having a height or depth for press-processed rough surface transfer, and further on the first uneven surface. A method for producing a metal part, characterized in that a second rough surface made of a rough surface (for example, a rough surface at a satin level) finer than the first rough surface is formed.
(2) In a resin-sealed metal part having a metal part made of a pressed metal molded body and a sealing resin for sealing the metal part,
A rough surface of the press process is formed on the sealed portion where the sealing resin is in close contact with at least a part of the metal part,
This press-processed rough surface is composed of a first concavo-convex surface that repeats fine concavo-convex portions and a second concavo-convex surface that is formed on the first concavo-convex surface and that has finer concavo-convex portions than the first concavo-convex surface. A resin-encapsulated metal part characterized by comprising.
(3) In a lead frame formed by metal pressing,
A rough surface of press work is formed in part,
This press-processed rough surface is composed of a first concavo-convex surface that repeats fine concavo-convex portions and a second concavo-convex surface that is formed on the first concavo-convex surface and that has finer concavo-convex portions than the first concavo-convex surface. A lead frame characterized by being configured.

  According to the present invention, a new mechanical roughening treatment can be performed on a metal material in place of a conventional chemical roughening treatment or mechanical roughening treatment, and a partial roughening treatment can be performed in a short time. An enabling metal press working method can be realized.

  In addition, the roughened surface of the metal part (metal stamped product) obtained by the roughening treatment is a combination of a finely processed first uneven surface and a finer second uneven surface. Because it is composed of a complex rough surface, it increases the effective interfacial adhesion (adhesion) area to the sealing resin in limited sealed parts, and even for metal parts that are narrowed, excellent hermetic sealing It is possible to realize a resin-sealed metal part and a lead frame that can maintain the above.

The longitudinal cross-sectional view which shows an example of the semiconductor package used as the application object of the resin sealing metal component of Example 1 of this invention, and its partial expanded sectional view. 1 is a perspective view of a resin-encapsulated metal part (lead frame) according to Embodiment 1. FIG. The longitudinal cross-sectional view which shows an example of the lithium ion battery used as the application object of the resin sealing metal component of Example 2 of this invention, and its principal part expanded sectional view. FIG. 4 is a partially enlarged sectional view of FIG. 3. Explanatory drawing (Example 3) which shows the press work rough surface formation process in one Example of the metal press processing method (manufacturing method of a metal press conductor) of this invention. Explanatory drawing (Example 3) which shows the punching process in one Example of the metal press processing method (manufacturing method of a metal press conductor) of this invention. When the workpiece W is punched using a punch and die of a punching die having a micro-grooving side surface, the work surface (work plate thickness side surface) of the workpiece W '(die-cut metal stamped product) and adjacent to it The figure which shows the non-processed surface to do. In Example 4, the figure which shows the observation result by the laser microscope of the punch which performed the blast process after the groove | channel process. The figure which shows the laser microscope observation result of the press work brass surface in Example 4. FIG. The front view and side view which show the specification of the test piece which concerns on this invention.

  Embodiments of the present invention will be described with reference to examples shown in the drawings.

  First, referring to FIGS. 1 and 2, a case where an embodiment of a resin-encapsulated metal part (conductor) is applied to a semiconductor package will be described. FIG. 1 is a longitudinal sectional view showing an example of a semiconductor package to which the resin-encapsulated metal part of the present embodiment is applied and a partially enlarged sectional view thereof. FIG. 2 is a perspective view of a resin-encapsulated metal part (lead frame) according to the present embodiment.

  1 includes, for example, a semiconductor chip 1 that constitutes a power transistor, a metal base 2 that supports the semiconductor chip, a lead frame 3 that serves as an input / output lead terminal, and a bonding that connects the semiconductor chip 1 and the lead frame 3. It consists of a wire 4 and a sealing resin 5 for sealing these members.

  The sealing resin 5 is, for example, a transfer mold resin, and part of the lead frame 3 that is a resin-sealed metal part (resin-sealed conductor) is resin-sealed, and the other part is drawn out to the outside. Yes.

  The lead frame 3 is a metal stamped product made of, for example, a copper alloy material. The lead frame 3 shown in FIG. 1 is schematically drawn for convenience of drawing, but is actually a plate-like one as shown in FIG. The lead frame 3 is not limited to a copper alloy, and other appropriate metal conductive materials such as aluminum, an aluminum alloy, and an iron-based alloy such as 42 alloy (42 mass% Ni—Fe alloy) can be used. A rough surface (roughening portion) 7 of press working is formed in which the sealing resin 5 is in close contact with a part (sealed portion) of the lead frame 3.

  As shown in the enlarged view of the main part of FIG. 1, the rough surface 7 subjected to press working includes a first uneven surface 7 a in which fine valleys formed on a part of the front and back surfaces of the lead frame 3 are repeated, and further A finer textured second uneven surface 7b formed on one uneven surface 7a, and a third uneven surface 7c formed on the side surface of the lead frame plate crossing the front and back surface portions having these uneven surfaces. (See FIG. 2). The 2nd uneven surface 7b consists of unevenness finer than the 1st uneven surface 7a. Further, if necessary, finer textured surface irregularities similar to those of the second irregular surface 7b are also formed on the third irregular surface 7c (not shown: this is referred to as 7d).

  The first concavo-convex surface 7a in the present embodiment is configured by arranging a large number of fine triangular protrusions having a concavo-convex height (valley to mountain) of 1 to 100 μm and a width (peak to mountain pitch) of 1 to 200 μm. Has been. The triangular protrusion may be formed by a convex / concave surface in which peak-shaped peaks and valleys repeat. The shape of the concavo-convex shape is an arbitrary pattern such as a conical shape, a pyramid shape, or a continuous groove shape as long as it can be processed.

  The second uneven surfaces 7b and 7d have an arithmetic average roughness (Ra) of 0.1 to 10 μm.

  The first and second uneven surfaces 7a and 7b are both formed by a roughening process by pressing.

  Furthermore, the 3rd uneven surface 7c formed in the plate | board thickness side surface in the lead frame 3 is 1-100 micrometers in uneven | corrugated height (valley-to-mountain), width | variety (peak-to-mountain pitch), and the depth of the range of 1-200 micrometers. It is formed by the press-punching surface of the fine groove row which repeats and has. Further, a roughened surface having an arithmetic average roughness (Ra) of 0.1 to 10 μm similar to the second uneven surface 7b may be formed on the surface of the third uneven surface 7c as necessary. .

  The specifications of these press-worked rough surfaces are set in a range that does not hinder the thickness (strength) of the metal part of the roughening target product. For example, if the thickness is about several tenths of a millimeter to several millimeters, If it is an above-mentioned numerical value, the intensity | strength of a metal plate material is securable.

  A method for forming these rough surfaces 7 (7a, 7b, 7c) will be described later.

  The roughening processing part 7 of the lead frame 3 is formed in a part of the lead frame, and a silver plating part 6 serving as a wire pad is formed in the vicinity of one end on the semiconductor chip side except for the roughening processing part 7. One end of the bonding wire 4 is connected to the portion 6 by an ultrasonic bonding method.

  According to the resin-encapsulated structure of the present embodiment, the roughening processing section 7 of the lead frame 3 can be realized by metal pressing that does not require complicated processing. In addition, the press-processed rough surface, which is a roughening treatment unit, is composed of a complex rough surface that is a combination of a first uneven surface for fine processing and a second uneven surface that is finer than that. Increases the area of interfacial adhesion (adhesion) to the sealing resin in the sealed part, and can maintain excellent hermetic sealing even for metal parts that are narrowed. A sealed lead frame can be realized.

  Next, with reference to FIG. 3 and FIG. 4, a case where another embodiment (embodiment 2) of the resin-encapsulated metal part is applied to a lithium ion battery will be described. FIG. 3 is a longitudinal sectional view showing an example of a lithium ion battery to which the present embodiment is applied, and FIG. 4 is a partially enlarged sectional view thereof.

  The lithium ion battery of FIG. 3 includes a positive electrode plate (positive electrode) 11, a negative electrode plate (negative electrode) 12, and a separator 13 interposed between these electrodes inside a bottomed cylindrical battery case 10 serving as a negative electrode terminal. A large number of electrode assemblies are stacked and mounted. In addition, the electrode assembly may have various shapes such as a structure in which the positive electrode plate 1 and the negative electrode plate 2 are formed by winding a separator 13 that insulates between them. Is also applicable. In addition, the case 10 is filled with a nonaqueous electrolytic solution (electrolyte).

  There are many types of materials for the positive electrode, the negative electrode, and the electrolyte, as long as they can move lithium ions and exchange lithium ions. There are many types of materials, and the characteristics vary depending on the types. Since a known material may be used, description thereof is omitted.

  The upper opening of the case 10 is sealed by an inner metal cap (for example, an aluminum cap) 14 after the electrode assembly is mounted in the case 10. The metal cap 14 is provided with a safety valve 15 for injecting a non-aqueous electrolyte and for releasing the gas in the case 10.

  The metal cap 14 is provided with a through hole 18 through which a lead frame 17 connecting the positive electrode plate 11 and the positive electrode terminal 16 is passed. The lead frame 17 is connected to the positive electrode plate 11 and the positive electrode terminal 16 through the through hole 18. One end of the lead frame 17 is caulked through a hole 20 provided in the positive electrode terminal 16.

  The positive terminal 16 is fixed to an outer exterior resin cap 19.

  An adhesive 21 is filled as a sealing resin between the lead frame 17 and the through hole 18 and between the positive terminal 16 and the metal cap 14. As the adhesive, for example, an epoxy-based adhesive is used, but the adhesive is not limited thereto. An appropriate insulating adhesive may be used, and resin molding using a molding die may be used.

  As shown in FIG. 4, in this embodiment as well, a part of the lead frame 17 (at least a portion to be sealed) has a roughened press-processed surface similar to that of the first embodiment in order to increase the interfacial adhesion area with the adhesive 21 ( (Roughening unit) 22 is provided. Further, metal parts other than the lead frame, that is, a part of the metal cap 14, that is, a part of the surface of the cap 14 to which the adhesive 21 is bonded and a rough surface 23 and 24 are provided on the hole wall of the through hole 18, respectively. .

  The press-work rough surface 22 provided on the lead frame 17 has first and second uneven surfaces provided on a part of both surfaces of the lead frame (the same press as the first and second uneven surfaces 7a and 7b of Example 1). Processed surface) and a third uneven surface (a press-processed surface similar to the third uneven surface 7c of Example 1) provided on the plate thickness side surface orthogonal to these uneven surfaces. If necessary, an uneven surface similar to the second uneven surface 7b may be formed on the third uneven surface 7c.

  The roughened press-worked surface 23 provided around the through hole 18 of the metal cap 14 is the same press-worked surface as the first and second uneven surfaces 7a and 7b of the first embodiment.

  The roughened press-worked surface 24 provided on the inner wall of the through hole 18 is formed of a press-worked surface similar to the third uneven surface 7c of the first embodiment. Further, an uneven surface similar to the second uneven surface 7b described above is formed on this surface as needed.

That is, in this embodiment, the roughened press working surface is provided in a portion passing through the through hole 18 of the metal cap 14 of the lead frame 17, the through hole 18 of the metal cap 14 and the periphery thereof, and the through hole 18 and the periphery thereof. In this embodiment, the sealing adhesive area between the lead frame and its peripheral metal member (such as a metal cap) to be narrowed is also reduced. It can be secured sufficiently, and the roughening process of metal parts that increase the adhesion area is realized by metal pressing, so it avoids the complexity of the manufacturing process like chemical roughening process, and it is limited to the necessary parts Roughening can be performed. Further, the surface of the positive electrode terminal 16 in contact with the adhesive also forms 7a and 7b as necessary.

  Next, a method for producing a metal part for resin sealing (metal pressing method) will be described by taking the above-described lead frame 3 as an example. The metal press working method of the present embodiment is not limited to the lead frame as long as it is a metal part for resin sealing, and can be applied to various types.

  FIG. 5 is an explanatory view showing a process of forming a rough surface by press transfer using a punch of a super hard die on a part of a metal surface of a lead frame (work: metal processing press product).

  When forming a rough surface for press working, as shown on the left side of the drawing, the bottom surface of the punch 50 serving as a die is precision fine for transferring the rough surface for pressing (corresponding to the first uneven surface 7a) by an end mill or a machining center. A processed surface 51 is applied. On the bottom surface of the punch, for example, a fine micro-processed surface 51 of a fine triangular projection row having a concavo-convex height (valley to mountain) of 1 to 100 μm and a width (peak to mountain pitch) of 1 to 300 μm is formed. The shape of the concavo-convex shape is an arbitrary pattern that can be processed, such as a continuous groove, a pyramid shape, or a conical shape, and may have any shape. Blasting is further applied to the surface of the fine irregularities. As a result, the bottom surface of the three-dimensional microstructure processing in which the fine blasting 52 (the second uneven surface 7b transfer press surface) is further performed on the fine uneven surface is obtained on the punch 50. When this punch 50 is pressed against the surface of a copper alloy used for a workpiece W (for example, copper alloy: metal material before lead frame processing) by a progressive press, the copper alloy surface is punched on the right side of the figure. A three-dimensional microstructured surface as shown in the section of the part is obtained.

  In the progressive press, a long strip-shaped metal strip can be pressed while being wound up, so that it is possible to partially and continuously process the fine irregularities continuously at the necessary portions of the copper alloy. Although the example of the punching surface has been described with reference to FIG. 5, the three-dimensional microstructure processing surface is also formed on the back surface of the workpiece (copper alloy) W by performing fine uneven processing and blasting on the die 55 side shown in FIG. (Roughened surface by pressing) is obtained.

  After the press-processed rough surface forming step in FIG. 6, the workpiece W is die-cut as shown in FIG. 6 by progressive press.

  On the left side of FIG. 6, on both sides of the punch 60 for punching (only one side is shown in the figure), the unevenness height (valley to mountain) for pressing rough surface transfer is 1 to 100 μm, and the width (mountain to mountain). An example in which fine grooves (or fine protrusion rows: for transferring the third uneven surface 7c in FIG. 1) 61 in the range of 1 to 300 μm is formed is shown. The fine groove 61 is also formed by precision fine processing using an end mill, a machining center, or the like. Further, fine grooves or protrusions are formed on the side surface of the die 65 for punching as well as the punch. In the case of punching using the punch 60 and the die 65 of the workpiece W (right side in FIG. 6), the fine grooves used for the punch and the die are precisely aligned. Further, if necessary, an uneven surface similar to the second uneven surface 7b is also formed on the uneven surface 7c by a blasting method or the like.

  When the workpiece W using the punch and die is punched, the processed metal part W ′ obtained by the punching process has the shape of a lead frame, and the uneven surface of the fine groove (the third example of the embodiment) An uneven surface 7c) is formed. Further, after the punching process, the second metal is also applied to the side surface of the processed metal part by pressing a punch having only the uneven surface (for transfer) similar to the second uneven surface 7b by blasting or the like from the side surface of the lead frame. An uneven surface is formed. The method of pressing the punch for forming the second uneven surface on the punching side surface is to move the press punch laterally by a cam drive system that converts the vertical movement of the press die into lateral movement. Yes. This method is often used for drilling from the lateral direction in deep drawing.

  In the present embodiment, the first uneven surface 7c (or the rough surface processing similar to the second uneven surface performed as necessary on the uneven surface 7c) by the side surface punching process is a post-process for the front and back surfaces of the lead frame. However, the formation process of the uneven surface 7c (or the second uneven surface applied to the 7c surface) is performed in the previous process, and then the first uneven surface process 7a and the rough surface process 7b are performed. You may perform a 2nd uneven | corrugated process.

  In Example 4, a groove having a depth of 50 μm and a pitch of 250 μm was formed by a machining center on a punch of die steel (SKD11). In Example 4, the grooving surface was further blasted with SiC fine particles. FIG. 8 shows the observation result of the punch subjected to the blasting after the groove processing by the laser microscope. The die side used was a die that was grooved and blasted in the same manner as the punch side.

The arithmetic average roughness Ra of the blasted surface of the punch was in the range of 3.0 to 4.0 μm. This processing punch was used to press the front and back surfaces of the copper alloy material (Zn32mass% -Cu). The press working was performed at a rotation speed of 100 RPM using a crank press machine. FIG. 9A shows the result of laser microscope observation of the pressed copper alloy material surface.
As shown in FIG. 9A, a roughened surface by transfer of a punch subjected to blasting is seen on the processed surface of the workpiece W (copper alloy material). For comparison, it can be seen that the pressed surface of the copper alloy material by the punch without blasting is smooth inside the groove as shown in FIG. The average roughness (Ra) of the roughened surface of the copper alloy material by the blasted punch and die was 3.0 to 4.0 μm, similar to the average roughness (Ra) of the blasted punch. Moreover, the average roughness (Ra) of the copper alloy material surface when not blasting was 0.2 to 0.3 μm.

  Furthermore, the 1st uneven | corrugated process (7c) was performed on the side of a punching process. This processed cross section is shown in FIG. As shown in FIG. 7, it can be seen that a groove having a pitch of 0.1 mm is formed on a cross section of a 0.64 mm copper alloy material (lead frame). The average depth of the groove as measured by a laser microscope was 3 μm.

  Using a test piece made of a copper alloy material on which these 7a, 7b, and 7c were formed, resin molding was performed around the test piece, and a gas leak test was performed. As shown in FIG. 10, the test piece for the gas leak test is formed on four surfaces, a front surface, a back surface, and a press-cut side surface of a copper alloy material having a thickness of 0.64 mm, a width of 4 mm, and a length of 70 mm in a central portion of 10 mm. On the other hand, uneven processing by a crank press is performed. The first (groove processing: equivalent to the first uneven surface 7a) and the second (rough surface processing: equivalent to the second uneven surface 7b) are provided on both the front and back surfaces of the test piece, and the third is provided on both side surfaces. Concavity and convexity processing (groove processing: equivalent to the third concave and convex surface 7c) is performed (this is referred to as an example test piece).

  Although the illustration of the gas leak test method is omitted, a resin hollow hose with an inner diameter of φ8 mm is inserted into one end and an 8 mmφ resin hollow hose is inserted into the other end, and air pressure at a pressure of 0.1 MPa is inserted into one hose. Were tested in a continuous pressure mode. The test time was 2 hours. The amount of leak was measured by collecting air leaking from the hose at the other end submerged in water with a lightweight bottle. The roughened copper alloy material (Zn32mass% -Cu) of this example was used as the copper alloy material having the unevenness forming press-worked portion shown in FIG. The copper alloy material was subjected to two rough surface processing depths (groove depths) of 0.05 mm (50 μm) and 0.1 mm (100 μm) of the first uneven surface 7a and the third uneven surface 7c. For comparison, the first concavo-convex surface 7a and the third concavo-convex surface 7c are provided, but a copper alloy material processed by a punch without blasting (without the second concavo-convex surface 7b) was also tested (compare this). Example called test piece). PPS resin was used as the molding resin. The resin mold temperature was 150 ° C.

  Table 1 summarizes the results of the gas leak test.

  The gas leak test was performed three times for each test piece. According to the result of the gas leak test, as shown in Table 1, the example test piece having any one of the first uneven surface 7a, the second uneven surface 7b, and the third uneven surface 7c has a groove shape. The depth of 50 μm is “0, 0, 0” in the three tests, and the depth of 100 μm is the leak amount in three tests (l / h). Was “0, 0, 0.033”, and it was proved that all of them were excellent in airtightness as compared with the test piece of the comparative example.

  Therefore, the metal to be narrowed by applying the rough surface processing according to the present invention to the parts that require resin sealing such as the lead package and cap of the semiconductor package and lithium ion battery of the above-described embodiment. Even with parts, an excellent hermetic sealing effect can be obtained.

  In addition, metal press processing that enables new simple mechanical roughening treatment to replace conventional complicated chemical roughening treatment and mechanical roughening treatment and enables partial roughening treatment in a short time. A method can be realized.

  In the above-described embodiments, the lead frame of the semiconductor package, the lead frame of the lithium ion battery, and the metal cap have been mainly described as examples of the resin-sealed metal parts. Any metal part can be used regardless of the type.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor chip, 3 ... Resin sealing metal component (lead frame), 5 ... Sealing resin, 7 ... Rough surface of press work, 7a ... 1st uneven surface, 7b ... 2nd uneven surface, 7c ... 3rd 14: Resin-encapsulated metal part (metal cap), 17: Resin-encapsulated metal part (lead frame), 22, 23, 24: Press-worked rough surface.

Claims (15)

In a resin-sealed metal part having a pressed metal part and a sealing resin for sealing the metal part,
A rough surface of the press process is formed on the sealed portion where the sealing resin is in close contact with at least a part of the metal part,
This press-processed rough surface is composed of a first concavo-convex surface that repeats fine concavo-convex portions and a second concavo-convex surface that is formed on the first concavo-convex surface and that has finer concavo-convex portions than the first concavo-convex surface. A resin-encapsulated metal part characterized by comprising. In the resin-sealed metal part according to claim 1,
The metal part is a lead frame;
The pressed rough surface is formed on a portion of the front and back surfaces of the lead frame and at least a portion to be the sealed portion except for a connecting portion with other components,
And the resin-sealed metal part in which the stamping process surface of a fine groove row is formed in the plate | board thickness side surface in the said to-be-sealed part in the said lead frame.   3. The resin-encapsulated metal part according to claim 2, wherein the press-cut surface of the plate thickness side surface is pressed with an uneven surface that is finer than the fine groove row of the press-cut surface. Stop metal parts. In the resin-sealed metal part according to any one of claims 1 to 3,
The first concavo-convex surface is a resin-encapsulated metal part configured with a concavo-convex surface in which peaks and troughs repeat continuously or intermittently.   4. The resin-encapsulated metal part according to claim 1, wherein the first concavo-convex surface is constituted by an assembly of a large number of fine protrusions. In the resin-encapsulated metal part according to any one of claims 1 to 5,
A resin-sealed metal part, wherein the sealing resin is a mold resin or an adhesive. In the resin-sealed metal part according to any one of claims 1 to 6,
The resin-encapsulated metal component is a lead frame used in a semiconductor package for encapsulating a semiconductor electronic component with a mold resin, and one end of the lead frame is connected to the semiconductor electronic component via wire bonding, and the other end is molded. A resin-encapsulated metal part in which the mold resin is in close contact with the roughened press-work surface provided on a part of the lead frame and drawn out to the outside of the resin. In the resin-sealed metal part according to any one of claims 1 to 6,
The resin-encapsulated metal part includes a lead frame that connects the positive electrode and the positive electrode terminal of a battery on which a positive electrode, a negative electrode, an electrolyte, and a separator are mounted, and a cap that closes a case that houses a battery electrode assembly, and the lead A frame is connected to the positive terminal through a through hole provided in the cap;
The rough surface for pressing is provided in a portion of the lead frame that passes through the through hole of the cap, the through hole of the cap, and the periphery thereof, and a sealing adhesive that fills the through hole and the periphery thereof is provided in the press. Resin-encapsulated metal parts that are in close contact with the roughened surface. In the resin-sealed metal part according to any one of claims 1 to 8,
The first uneven surface has an uneven height difference of 1 to 100 μm, an uneven width of 1 to 200 μm,
A resin-encapsulated metal part in which the second uneven surface has an arithmetic average roughness (Ra) of 0.1 to 10 μm. In the resin-sealed metal part according to any one of claims 2 to 8,
The stamped surface of the fine groove array on the side surface of the plate thickness is a resin-encapsulated metal part having an uneven height difference of 1 to 100 μm and an uneven width of 1 to 200 μm. The resin-encapsulated metal part according to any one of claims 3 to 8,
The resin-encapsulated metal part having an arithmetic mean roughness (Ra) of 0.1 to 10 [mu] m on the uneven surface finer than the fine groove row on the plate thickness side surface. In a lead frame formed by metal press processing,
A rough surface of press work is formed in part,
This press-processed rough surface is composed of a first concavo-convex surface that repeats fine concavo-convex portions and a second concavo-convex surface that is formed on the first concavo-convex surface and that has finer concavo-convex portions than the first concavo-convex surface. A lead frame characterized by being configured. The lead frame according to claim 12,
The pressing rough surface is formed on a part of both the front and back surfaces of the lead frame,
The lead frame is formed with a punched surface of a fine groove array on a plate thickness side surface that intersects the roughened surface of the press frame. In the manufacturing method of metal parts by metal pressing,
A step of forming a press-worked rough surface by press transfer using a punch and die of a super-hard mold on one side or part of both sides of a metal plate material to be a workpiece;
After the pressing rough surface step, the metal plate material is punched to obtain the metal part, and a fine groove row press punching surface is formed on the thickness side of the metal part that intersects the pressing rough surface. And a process of
In addition, the punch and die used for forming the press-process rough surface include a first uneven surface having a height or depth for press-process rough surface transfer, and the first uneven surface formed on the first uneven surface. A method for producing a metal part, comprising: a second rough surface for transferring a roughened surface by pressing, which is made of unevenness finer than the one uneven surface. In the manufacturing method of the metal component of Claim 14,
The first uneven surface for transfer formed on the punch and die is formed by an end mill or a machining center, and the second uneven surface for transfer is subjected to a blasting process on the first uneven surface. A method for manufacturing formed metal parts.

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