JP5562819B2 - Manufacturing method of semiconductor device - Google Patents

Description

  The present invention relates to a manufacturing technology of a resin-encapsulated semiconductor device using a lead frame, and is particularly intended for a side of a package such as SON (Small Outline Non-Leaded Package) and QFN (Quad Flat Non-Leaded Package). In particular, the present invention relates to a technique effectively applied to the manufacture of a semiconductor device (non-lead type semiconductor device) in which an external electrode terminal is exposed on the mounting surface side without protruding.

  A resin-encapsulated semiconductor device uses a lead frame in its manufacture. The lead frame is manufactured by forming a metal plate into a desired pattern by punching or etching with a precision press. The lead frame has a support portion called a tab for fixing the semiconductor chip, and a plurality of leads that have their tips (inner ends) faced around the support portion. The tab is supported by a tab suspension lead extending from the frame portion of the lead frame.

  When manufacturing a resin-encapsulated semiconductor device using such a lead frame, the semiconductor chip is fixed to the tab of the lead frame, and the electrode of the semiconductor chip and the tip of the lead are connected by a conductive wire. Then, the inner end side of the lead including the wire and the semiconductor chip is sealed with an insulating resin (resin) to form a sealed body (package), and then the unnecessary lead frame portion is cut and removed and protrudes from the package. Cut the leads and tab suspension leads to be removed from the frame.

  On the other hand, as one of the resin-encapsulated semiconductor devices manufactured using a lead frame, a single-sided mold is performed on one side of the lead frame to form a package, and the leads as external electrode terminals are exposed on the mounting surface of the package. A semiconductor device structure in which leads are not intentionally projected from the peripheral surface of the package is known. This semiconductor device is known to be a SON in which leads are exposed on both side edges of the package mounting surface, and a QFN in which leads are exposed on the four sides of the mounting surface of the rectangular package.

  SON is described in Patent Document 1 (Japanese Patent Laid-Open No. 10-34699) and Patent Document 2 (Japanese Patent Laid-Open No. 10-70217). The former discloses a technique in which resin sealing is performed by covering a mold surface with a release film having flexibility and heat resistance so that resin flash does not occur during resin sealing in the manufacture of semiconductor devices. ing.

  In the latter, a technique is disclosed in which a groove having a substantially arc-shaped cross section is provided on the surface of the mold resin between the leads to ensure a long insulation distance between the leads and to prevent a resin burr generated on the lead exposed surface. .

  Further, in Patent Document 3 (Japanese Patent Laid-Open No. 10-270603), a semiconductor chip is fixed on the surface of a substrate (a resin substrate made of glass epoxy resin or the like) like a ball grid array semiconductor device, and a lattice is formed on the back surface of the substrate. A semiconductor device (area package type semiconductor device) in which external electrodes are provided in a shape and the surface of the substrate is covered with a resin package covering the semiconductor chip and the like, and a manufacturing method thereof are disclosed. A plurality of the semiconductor devices are provided in a line on the substrate.

  In addition, when the substrates are stacked, protrusions higher than the height of the resin package are provided on at least two corners of the package so that the electrodes are not damaged, and the electrode surface contacts the resin package. I try not to.

  Unless two protrusions are formed in a direction intersecting the longitudinal direction of the substrate, the electrode cannot be protected when the substrates are stacked.

JP-A-10-34699 Japanese Patent Laid-Open No. 10-70217 JP-A-10-270603

  Non-lead type semiconductor devices such as SON and QFN by single-sided molding are used from the viewpoint of miniaturization of semiconductor devices and prevention of lead bending of leads serving as external electrode terminals.

  Compared with semiconductor devices such as SOP (Small Outline Package) and QFP (Quad Flat Package), the lead surface exposed on the package mounting surface is the mounting surface because the lead surface exposed on the package mounting surface is the mounting surface. And the mounting area is small. For this reason, if foreign matter adheres to the surface of the lead (external electrode terminal) or is damaged, the mounting reliability is lowered.

  34 to 36 are partial schematic diagrams showing a state in which the non-lead type semiconductor device 1 is mounted on a wiring substrate 50 such as a mother board. Leads exposed on the mounting surface 3 of the package 2 of the non-lead type semiconductor device 1 are shown. The (external electrode terminal) 4 shows a state in which it is bonded to a land 52 (not shown) of the wiring board 50 via a bonding material (solder) 51. A plating film 54 is provided on the surface of the lead 4, that is, the mounting surface, in order to improve the solder wettability. In the figure, the plating film 54 is indicated by a thick black line. The plating film 54 is formed of a solder film made of lead and tin, or a palladium plating film for not using lead as a solder.

  This is called pre-plating, and the palladium plating film is already plated in the state of the lead frame. In addition, the solder film is referred to as post-plating and is plated after molding. In the case of a solder film, solder is used as the solder. In the case of a palladium plated film, a lead-free solder, for example, Sn—Zn or Sn—Ag is used.

  FIG. 34 shows a normal mounting form in which no mounting abnormality has occurred. For example, the solder as the solder 51 gets wet over the entire mounting surface side of the lead 4, and the fillet 55 is formed high on the outer end surface of the lead 4, so that it is understood that the solder solderability is also good from the outside.

  As shown in FIG. 35, if the foreign matter 56 adheres to the surface (exposed surface) of the lead 4, electrical connection is not made at the attached portion, and conduction failure tends to occur.

  As shown in FIG. 36, a portion where the surface (exposed surface) of the lead 4 is scratched and the plating film 54 is removed is not attached with the solder 51, and is likely to have poor conduction due to a reduction in connection area. In FIG. 36, since the part where the plating film 54 is peeled off and peeled off is on the outer end side of the lead 4, a fillet is not formed, and connection failure can be visually observed, but when the scratch is inside, It is not visible from the outside, and it is impossible to check for poor continuity. This causes a reduction in implementation reliability.

  As described above, in the non-lead type semiconductor device, it is necessary to avoid that foreign matters adhere to the lead mounting surface or that the plating surface is peeled off due to scratches on the lead mounting surface. The same applies to the manufacture of non-lead type semiconductor devices.

  In the present applicant, a non-lead type semiconductor device such as QFN or SON is manufactured using a metal matrix type lead frame. In the matrix type lead frame, one unit pattern of the lead frame (hereinafter referred to as a unit lead frame pattern) is arranged in a plurality of rows and columns along the vertical and horizontal directions. Then, one non-lead type semiconductor device is manufactured for each unit lead frame pattern of the matrix type lead frame. That is, after fixing the semiconductor chip to the center portion of each unit lead frame pattern, the electrode of this semiconductor chip and the inner end of the lead are connected by a conductive wire, and then the semiconductor chip and the wire are molded on one side to form a package. To do.

  By the way, in the manufacture of a non-lead type semiconductor device using a matrix type lead frame, the applicant of the present application forms a package in each unit lead frame pattern part, and then stores the matrix type lead frame in a storage or cutting device. During loading, the matrix type lead frames are sequentially stacked and handled.

  In this case, the lead frame is overlaid on the package formed of an insulating resin. In some cases, the lead frame surface serving as the mounting surface may be overlaid on the package. At this time, the lead frame surface serving as the mounting surface may become dirty or scratched.

  Therefore, the present inventor considered forming a contact prevention body having a height higher than that of the package so that the lead frame surface serving as the mounting surface does not come into contact with the package formed on the lower lead frame. It was. Then, it was considered to form this contact prevention body in a flow cavity portion continuous with a cavity of a mold mold for forming a package.

  That is, the flow cavity is provided to prevent air in the cavity from remaining in the cavity. Therefore, the height (depth) of the flow cavity is made higher than the height (depth) of the cavity, and the contact prevention body is formed from a resin cured in the flow cavity.

  On the other hand, as described above, the technique described in Patent Document 3 is known as a technique for preventing the external electrodes in the ball grid array semiconductor device from being damaged.

  However, it has been found that this technology cannot be applied to the manufacture of a non-lead type semiconductor device using a matrix type lead frame as it is.

  That is, the ball grid array semiconductor device manufacturing method described in Patent Document 3 is a technique for forming a semiconductor device by forming a square resin package in a line along the longitudinal direction of an elongated substrate. As an embodiment, resin is injected from one corner of a rectangular cavity to form a resin package, and protrusions are formed at the remaining two to three corners. A reservoir is provided in the air vent of the mold of the transfer mold, and a protrusion that is higher than the height of the resin package is formed by the resin cured in the reservoir.

  The matrix type lead frame forms n rows and m columns of packages along the length and width of the lead frame. Therefore, if the conventional manufacturing technology of the ball grid array semiconductor device is applied as it is, the resin flows into the m × n cavities and the 2 to 3 × m × n reservoirs at the time of molding, so that the package and the projecting portion respectively. Therefore, the amount of resin sent to the runner connected to the cavity is greatly increased.

  As a result, it takes more time for the cavity to be farther from the pot to fill the resin, the resin viscosity increases, the wire flows by the flow of the resin, tilts, and contacts with the adjacent leads and electrodes, causing a short circuit. The frequency of making it high.

  Since the technology described in Patent Document 3 has a structure in which electrodes of a semiconductor chip are connected to a resin substrate such as a glass epoxy resin by face-down bonding, there is no need to consider the problem of short-circuit failure due to wire flow. is there.

  Further, in the conventional manufacturing method, the capacity of the transfer mold apparatus must be increased due to the increase in the amount of injected resin and the increase in injection pressure, which increases the cost of the transfer mold apparatus and increases the manufacturing cost of the semiconductor device.

  Further, in the conventional manufacturing method, since two to three protrusions are formed for one package, the amount of resin used is increased and the manufacturing cost of the semiconductor device is increased.

  In addition, when the conventional configuration in which two to three reservoirs of the cavity are arranged is applied to a matrix type lead frame, the lead frame becomes large for forming the reservoir. The technique described in Patent Document 3 needs to provide protrusions on at least two corners of the package, and when applied to a matrix type lead frame, the unit lead frame pattern becomes large and the frame use efficiency is low. This increases the manufacturing cost of the semiconductor device.

  The technique described in Patent Document 3 requires protrusions on at least two corners of the package, and when applied to a matrix type lead frame, the amount of resin used increases and the manufacturing cost of the semiconductor device increases. Becomes higher.

  An object of the present invention is to provide a method for manufacturing a non-leaded semiconductor device having good mounting performance.

  Another object of the present invention is to provide a method of manufacturing a non-lead type semiconductor device that does not cause scratches or foreign matter adhesion on the mounting surface of the external electrode terminal.

  Another object of the present invention is to provide a method of manufacturing a non-leaded semiconductor device that can achieve a reduction in manufacturing cost.

  Another object of the present invention is to provide an electronic device manufacturing method with excellent quality and high reliability.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  The following is a brief description of an outline of typical inventions disclosed in the present application.

  (1) A semiconductor device having a sealing body (package) made of an insulating resin, a lead exposed on a mounting surface of the sealing body, and a tab suspension lead, and the semiconductor device is located at an edge of the sealing body There is no burr due to cutting at the edge on the outer end mounting surface side of the lead and tab suspension lead. A semiconductor chip is located in the sealing body, and a tab connected to the tab suspension lead is embedded in the sealing body. The semiconductor chip is fixed on a fixing surface of the tab continuous to the tab suspension lead, and the tab is a semiconductor. It is smaller than the chip and thinner than the lead, and the electrode of the semiconductor chip and the lead are connected by a conductive wire. A plating film is formed on the lead surface and the tab suspension lead surface exposed on the mounting surface of the sealing body.

  Such a semiconductor device is manufactured by the following manufacturing method. That is, a frame, a tab positioned inward of the frame, a plurality of tab suspension leads extending from the frame toward the tab and supporting the tab at a tip portion, and the frame A step of preparing a matrix type lead frame in which a plurality of unit lead frame patterns including a plurality of leads extending toward the tab are arranged vertically and horizontally; a step of fixing a semiconductor chip on one surface of the tab; and the semiconductor The step of connecting the electrode of the chip and the inner end of the lead with a conductive wire, and covering the semiconductor chip, the wire, and the inner end portion of the lead with a sealing body made of an insulating resin by single-sided molding, A step of exposing the leads and the tab suspension leads to the mounting surface of the sealing body during molding, and a cutting step of cutting the leads and the tab suspension leads. That a method of manufacturing a semiconductor device, when the single-sided mold, as well as one form thick contact prevention body than the package outside of the package, is cut off the contact prevention member in the cutting step.

  After the single-sided molding, plating is performed to form a plating film for mounting at a predetermined location of the matrix type lead frame.

  In the cutting step, a punch is protruded from the mounting surface side of the sealing body, and the lead and the tab suspension lead are cut with a die and a punch.

  According to the means of (1), (a) when forming a package, a contact prevention body thicker than the thickness of the package is formed on the outside of the package. In this lead frame, since the contact preventer is interposed, the portion that becomes the external electrode terminal of the upper lead frame does not come into contact with the lower package, and contamination and scratching of the portion that becomes the external electrode terminal can be suppressed. As a result, a non-leaded semiconductor device with high mounting reliability can be provided.

  (B) Since only one contact preventer is formed per package, the amount of resin used is not large even in the case of a matrix type lead frame. As a result, the injection resin pressure at the time of transfer molding does not need to be so high, and the controllability of the transfer mold does not become difficult. Moreover, the transfer mold apparatus conventionally used can be used as it is.

  (C) Due to the fact that the amount of the injected resin at the time of transfer molding is not large due to the above (b), in the final cavity that is finally fed from the runner, there is no longer a short-circuit failure that occurs due to the wire falling down due to the flow of the resin. And improved reliability.

  (D) According to the above (b), since only one contact preventer is formed per package, the pattern size of the unit lead frame pattern can be reduced, and the use efficiency of the lead frame can be increased.

  (E) When cutting the leads and tab suspension leads, the punch protrudes from the mounting surface side of the sealing body, and the leads and tab suspension leads are cut by the die and the punch. A cutting burr will occur, and no cutting burr will occur on the mounting surface side. As a result, not only the appearance of the manufactured non-leaded semiconductor device is improved, but also mounting defects due to cutting burrs do not occur.

  (F) With the above (a) to (e), the manufacturing cost of the semiconductor device can be reduced.

  The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.

  (1) When manufacturing a semiconductor device Since scratches and foreign matter are unlikely to adhere to the mounting surface of the external electrode terminal, a non-lead type semiconductor device with good mounting performance can be manufactured.

  (2) Since no cutting burr is generated at the cutting edge of the lead on the mounting surface side of the external electrode terminal and the tab suspension lead, there is no mounting defect due to the cutting burr, and the mounting reliability can be improved.

  (3) Since the mounting surface of the external electrode terminal of the non-lead type semiconductor device is less likely to adhere to the mounting surface of the non-lead type semiconductor device at the time of manufacturing the electronic device, the non-lead type semiconductor device has good mounting performance and excellent quality and reliability. High electronic devices can be manufactured.

In the manufacturing method of the semiconductor device which is one embodiment (embodiment 1) of the present invention, it is a partial typical sectional view showing the state where the single sided lead frame was piled up. Embodiment 1 is a schematic perspective view of a semiconductor device from which a part is removed. It is sectional drawing of the said semiconductor device. It is a bottom view of the semiconductor device. It is sectional drawing which shows the mounting state of the said semiconductor device. 3 is a flowchart showing a method for manufacturing the semiconductor device of the first embodiment. 6 is a plan view of a lead frame used in the method for manufacturing a semiconductor device of Embodiment 1. FIG. FIG. 3 is a plan view showing a unit lead frame pattern portion of the lead frame. FIG. 6 is a plan view showing a state in which a semiconductor chip is fixed to a lead frame in the semiconductor device manufacturing method of Embodiment 1; It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. In the manufacturing method of the semiconductor device of this Embodiment 1, it is a top view showing the state where the electrode of a semiconductor chip and the lead inner end part were connected with the wire. It is sectional drawing which follows the CC line of FIG. It is a schematic diagram which shows the mold metal mold | die, lead frame, etc. at the time of the single-sided molding in the manufacturing method of the semiconductor device of this Embodiment 1. It is sectional drawing which shows the package, contact prevention body, etc. which were formed by the said single-sided mold. It is sectional drawing which shows the package etc. which were formed by the said single-sided mold. It is a top view which shows the correlation with the cavity and resin flow path, and lead frame which are formed with the mold metal mold | die in the said single-sided mold. It is an expanded sectional view which shows the relationship between the resin sheet used in the said single-sided mold, a package, etc. It is a top view of the lead frame in which the package was formed by the said single-sided mold. It is a top view which shows the unit lead frame pattern part in which the package was formed by the said single-sided mold. It is sectional drawing which shows the package etc. of the said unit lead frame pattern part. It is a perspective view which shows a part of cutting device used with the manufacturing method of the semiconductor device of this Embodiment 1. FIG. It is a schematic diagram which shows the composite cutting die integrated in the said cutting device. FIG. 6 is a partial schematic diagram illustrating stacked single-sided lead frames in the method of manufacturing a semiconductor device according to the first embodiment. FIG. 4 is a plan view of a part of the lead frame showing the gate-curing resin portion and the flow-cavity-curing resin portion to be cut in the method for manufacturing a semiconductor device of the first embodiment. It is typical sectional drawing which shows an example of a cutting die. FIG. 6 is a plan view of a lead frame showing a lead portion extending along the X direction to be cut in the method for manufacturing a semiconductor device according to the first embodiment. FIG. 6 is a plan view of a lead frame showing a lead portion extending along a Y direction to be cut in the method for manufacturing a semiconductor device of Embodiment 1. In the manufacturing method of the semiconductor device of this Embodiment 1, it is a top view of a lead frame portion showing a cutting part by pinch cut. FIG. 3 is a plan view showing a semiconductor device cut and separated from the lead frame. In this Embodiment 1, it is sectional drawing which shows the other semiconductor device manufactured using the flat lead frame in which a lead, a tab, and a tab suspension lead are located on the same plane. It is a bottom view of the other semiconductor device. In Embodiment 1, it is sectional drawing which shows the other semiconductor device manufactured using the lead frame which raised the tab suspension lead one step in the middle and floated the tab. It is a partial cross-sectional view showing a non-leaded semiconductor device in a good mounting state. FIG. 5 is a partial cross-sectional view showing a non-leaded semiconductor device with mounting failure due to foreign matter adhesion. FIG. 6 is a partial cross-sectional view showing a non-leaded semiconductor device with poor mounting due to peeling of a plating film. It is the perspective view which removed a part of semiconductor device manufactured with the manufacturing method of the semiconductor device which is other embodiment (Embodiment 2) of this invention. It is sectional drawing of the semiconductor device manufactured by the manufacturing method of this Embodiment 2. It is a bottom view of the semiconductor device manufactured with the manufacturing method of this Embodiment 2. 10 is a flowchart showing a method for manufacturing the semiconductor device of the second embodiment. FIG. 10 is a plan view of a lead frame used in the method for manufacturing a semiconductor device according to the second embodiment. FIG. 6 is a bottom view showing a back surface of a unit lead frame pattern portion of the lead frame. In the manufacturing method of the semiconductor device of this Embodiment 2, while fixing a semiconductor chip, it is a partial top view showing the state where the electrode and lead of a semiconductor chip were connected with the wire. It is typical sectional drawing which shows the single-sided mold state in the manufacturing method of the semiconductor device of this Embodiment 2. It is a top view of the lead frame in which the package was formed by the said single-sided mold. It is a top view which shows the unit lead frame pattern part in which the package was formed by the said single-sided mold. It is sectional drawing of the unit lead frame pattern part by which the said single-sided molding was carried out. FIG. 10 is a partial schematic diagram illustrating stacked one-side molded lead frames in the method of manufacturing a semiconductor device according to the second embodiment. FIG. 10 is a partial cross-sectional view showing stacked one-side molded lead frames in the method of manufacturing a semiconductor device according to the second embodiment. In the manufacturing method of the semiconductor device of this Embodiment 2, it is a typical top view of the unit lead frame pattern part which formed the notch in the tab suspension lead. In the manufacturing method of the semiconductor device of this Embodiment 2, it is a mimetic diagram showing the relation between the tab suspension lead on the gate side and the flow cavity side, the punch, the die, and the like. It is typical sectional drawing which shows the cutting state of the said gate hardening resin part and a flow cavity hardening resin part. It is a schematic diagram which shows the state which peels a resin sheet from the semiconductor device manufactured by this Embodiment 2. FIG. It is the top view and bottom view of the semiconductor device with which the edge of the package was missing.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment of the invention, and the repetitive description thereof is omitted.

(Embodiment 1)
1 to 33 are diagrams relating to a method of manufacturing a semiconductor device according to an embodiment (Embodiment 1) of the present invention.

  First, the manufacture of a QFN type semiconductor device, which is an example of a non-lead type semiconductor device manufactured by the semiconductor device manufacturing method of the first embodiment, will be described. 2 is a perspective view in which a part of a QFN type semiconductor device is removed, FIG. 3 is a sectional view, and FIG. 4 is a bottom view.

  In the QFN type semiconductor device 1, as shown in FIGS. 2 to 4, the sealing body (package) 2 made of an insulating resin is made of a flat rectangular body (rectangular body), and the corners (corners) are A chamfering process is performed to form a slope 5. One inclined surface 5 is a portion connected to a gate into which resin (resin) is injected at the time of forming the package 2, and the other three inclined surfaces 5 are air vent portions from which air escapes when the package 2 is molded. It is the place that was connected.

  Moreover, as shown in FIG.2 and FIG.3, the side surface of the package 2 is an inclined surface. This inclined surface is a result of making the side surface of the cavity into an inclined surface for facilitating extraction when the package is extracted from the cavity of the mold. Therefore, as shown in FIG. 3, the upper surface 6 is smaller than the size of the mounting surface 3 serving as the lower surface.

  External electrode terminals (leads) 4 are exposed on the back surface of the package 2, that is, on the periphery of the mounting surface 3. On each side, the leads 4 are arranged at a predetermined pitch along each side of the package 2. Further, tab suspension leads 7 are exposed at the four corners of the package 2, that is, at the periphery of the mounting surface 3 corresponding to the respective centers of the inclined surfaces 5 (see FIGS. 2 and 4).

  As shown in FIG. 2, the lead 4 and the tab suspension lead 7 slightly protrude outward from the rising edge 2 a of the package 2 on the surface of the lead 4 and the tab suspension lead 7 covered with the package 2. This is a portion that becomes a receiving portion of the die when the lead 4 and the tab suspension lead 7 are cut, and is, for example, 0.1 mm or less. There is a resin burr 10 between each lead 4 and between the tab suspension lead 7 and the lead 4. Since this resin burr 10 is also cut by a die and a punch, the edge of the resin burr 10 and the lead are formed at the periphery of the package 2. 4 and the tip edge of the tab suspension lead 7 are straight without being uneven.

  Since the semiconductor device 1 performs transfer molding after mold clamping with a sheet interposed in its manufacture, the mounting surface 3 is located on the inner side of the exposed surface of the lead 4 and the tab suspension lead 7, that is, the mounting surface 16. It becomes a hollow shape. In the first embodiment, after one-side molding by transfer molding, a plating film is formed on the surface of the lead 4 and the tab suspension lead 7. The structure is such that the mounting surface 16 of the suspension lead 7 is retracted inside. Thus, in the structure in which the mounting surface 3 of the package 2 is offset from the mounting surface 16 of the lead 4 or the tab suspension lead 7, when the semiconductor device 1 is surface-mounted on a wiring board such as a mounting board, the solder wet region is Since it is specified, there is a feature that solder mounting is good.

  As shown in FIG. 3, the semiconductor device 1 has a tab 11 in the package 2. A semiconductor chip 13 is fixed to the upper surface of the tab 11 via a bonding material 12. The tab 11 is a small tab smaller than the semiconductor chip 13. The tab 11 is structured to be supported by the four tab suspension leads 7 (see FIG. 2). The tab 11 and the tab suspension lead 7 are integrated.

  Further, the electrode 14 (see FIG. 2) formed on the surface of the semiconductor chip 13 and the inner end portion of the lead 4 are electrically connected by a conductive wire 15. The tab 11, the semiconductor chip 13 and the wire 15 are located in the package 2. The connection means for electrically connecting the electrode of the semiconductor chip 13 and the lead 4 may have other configurations.

  When the tab suspension lead 7 is used as an external electrode terminal, the ground electrode of the semiconductor chip 13 and the tab suspension lead 7 may be connected by a wire 15.

  FIG. 5 is a cross-sectional view of the semiconductor device 1 mounted on the wiring board 20. An electrode (land) 21 is provided on one surface of the wiring board 20 so as to correspond to the lead 4 and the tab suspension lead 7 which are external electrode terminals of the semiconductor device 1. The leads 4 and the tab suspension leads 7 that are external electrode terminals of the semiconductor device 1 are overlaid on the lands 21 and are electrically connected via a bonding material 22 such as solder.

  Next, specific manufacturing of the semiconductor device will be described. FIG. 6 is a flowchart showing a method of manufacturing a QFN type semiconductor device according to the first embodiment. The semiconductor device 1 is manufactured through steps 101 to 108.

  That is, after the work starts, chip bonding (S101), wire bonding (S102), mold (S103), plating (S104), gate / flow cavity curing resin cutting (S105), primary lead tip cutting (S106), first Manufactured through the respective steps of secondary lead tip cutting (S107) and residual tab suspension lead cutting (S108), the operation is completed. The gate / flow cavity curing resin cutting (S105), the primary lead tip cutting (S106), the secondary lead tip cutting (S107), and the remaining tab suspension lead cutting (S108) are performed by cutting using a composite cutting die. is there.

  In the manufacture of the semiconductor device 1 of Embodiment 1, a lead frame 25 having a matrix configuration as shown in FIG. 7 is prepared. In this lead frame 25, unit lead frame patterns 26 are arranged in 20 rows along the X direction and 5 columns along the Y direction, and 100 semiconductor devices 1 can be manufactured from one lead frame 25. On both sides of the lead frame 25, guide holes 27a to 27c used for conveying and positioning the lead frame 25 are provided.

  In addition, a runner is located on the left side of each row during transfer molding. Therefore, in order to peel off the runner curing resin from the lead frame 25 by ejecting the ejector pin, an ejector pin hole 28 through which the ejector pin can pass is provided. In addition, an ejector pin hole 29 through which the ejector pin can pass is provided in order to peel off the gate-cured resin, which is branched from the runner and hardened at the gate portion flowing into the cavity, from the lead frame 25 by the ejection of the ejector pin.

  FIG. 8 is a plan view showing the unit lead frame pattern 26. The unit lead frame pattern 26 includes a rectangular frame-shaped frame portion 30, a plurality of leads 4 extending inward from the inside of each side of the frame portion 30, and the frame inward from the four corners of the frame portion 30. Each of the patterns has a tab suspension lead 7 that supports the central tab 11 and is a rectangular area. The frame portion 30 is provided with slits 31 intermittently in the direction of each side so that the frame portion supporting the lead 4 can be changed elastically.

  As shown in FIG. 8, a rectangular area including the inner end portion of each lead 4 and the tab 11 is a cavity 32 formed by a mold. A gate (G) for injecting resin into the cavity 32 is connected to the upper left corner of the cavity 32 facing the ejector pin hole 29. Although not shown, a flow cavity (FC) communicates with the lower right corner of the cavity 32 facing the gate, and an air vent (E) communicates with the flow cavity. In addition, air vents communicate with the remaining two corners (upper right corner and lower left corner) of the cavity 32, although not shown.

  In the first embodiment, the contact preventer having a height higher than that of the package is formed by the resin cured in the flow cavity. Further, in order to increase the adhesive force between the lead frame and the contact prevention body so that the contact prevention body does not peel from the lead frame, an opening 33 is provided in the frame portion 30 in which the flow cavity (FC) is formed. . In the first embodiment, one symmetric shape is provided on each side of the extension line of the tab suspension lead 7.

  Holes 34 are provided in the frame portions 30 at the upper right and lower left corners, respectively. This hole 34 overlaps with the air vent, and the air vent cured resin bites into the frame portion 30 and functions to prevent the air vent cured resin from falling off.

  Further, as shown in FIGS. 10 and 11, the back surface of the tab 11 and the tab suspension lead 7 portion on the tab 11 side are thinned by a predetermined thickness etching (half etching). For example, when the thickness of the lead frame is 0.2 mm, the half etching depth is about 0.11 mm, and the thickness of the tab 11 is 0.09 mm.

  By doing so, the tab 11 is not exposed on the mounting surface of the package formed by single-sided molding. In addition, such a half-etched structure can reduce the thickness of the package by the height of the tab suspension lead as compared with a structure in which the tab 11 is raised in the middle and the tab 11 is embedded in the package. As a matter of course, the surface of the tab 11 and the tab suspension lead 7 that are not etched and the surface of the lead 4 corresponding to this are positioned on the same plane.

  The inner end of the lead 4 is inclined by the etching process. This is to prevent the lead 4 from coming out of the package.

  The semiconductor device 1 is manufactured using such a lead frame 25. That is, as shown in FIGS. 9 to 11, after fixing the semiconductor chip 13 on the tab 11 via the bonding material 12 (chip bonding: S101), as shown in FIGS. The electrode 14 and the inner end of the lead 4 are electrically connected by a conductive wire 15 (wire bonding: S102).

  Next, the package 2 is formed by performing single-sided molding on the lead frame 25 that has been assembled (mold: S103). This single-sided molding is performed by a transfer mold apparatus.

  FIG. 14 is a schematic view showing a mold, a lead frame and the like at the time of single-sided molding. A mold die attached to the transfer mold apparatus includes a lower die 35 and an upper die 36 disposed on the lower die 35, and assembly is performed between the mating surfaces (parting surfaces) 35a and 35b. The finished lead frame 25 is sandwiched. In FIG. 14, the lead frame 25 is displayed in a floating state, but actually, it is placed on the parting surface 35 a of the lower mold 35.

  In the first embodiment, single-sided molding is performed by a sheet molding method in which molding is performed with a sheet 37 interposed between the lead frame 25 and the upper mold 36. In the sheet mold method, when a lead frame is sandwiched between an upper mold and a lower mold, a flexible resin sheet is interposed between the upper mold and the lead frame to lead by the clamping force of the mold mold. This is a technique in which the back surface (mounting surface) of the package is offset with respect to the electrode mounting surface by resin sealing in a state where the electrode portion of the frame is bitten into the sheet.

  The parting surface 36a of the upper mold 36 is actually provided with a groove or the like partially so as not to cause wrinkles on the sheet, but is a flat surface in the drawing. And the groove | channel and hollow which the resin which melted | dissolved in the parting surface 35a of the lower metal mold | die 35 flow are formed. In FIG. 14, the runner 38, the gate 39, the cavity 32, the through 40, and the flow cavity 41 are arranged from left to right. Although not shown, an air vent is disposed on the side of the flow cavity 41 in a communicating state. Air vents are also arranged in front of and behind the cavity 32, respectively. For example, the cavity 32 has a depth of 0.8 to 0.9 mm, the flow cavity 41 has a depth of 1.1 to 1.2 mm, the through 40 has a depth of 0.3 to 0.4 mm, and air. The depth of the vent is 20-30 nm.

  FIG. 17 is a schematic plan view showing the correlation between the lead frame and the cavity or resin flow path formed by the mold. Since the lead frame 25 is arranged in 20 rows and 5 columns, the cavity 32 of the lower mold 35 is also arranged in 20 rows and 5 columns correspondingly. There are five pots (calves) 42 for storing the material for the mold, and four runners 38 extend from each curl 42, and five gates 39 extend from each runner 38 one after another. Resin (resin) is guided to the cavities 32 arranged in the row direction.

  At the time of single-sided molding, the lead frame 25 is positioned and placed on the parting surface 35a of the lower mold 35, and then the upper mold 36 is overlapped with the lower mold 35 to perform mold clamping.

  Next, the resin is put into the pot (cal) 42, and the heated resin is pressurized with a plunger and pushed out to the runner 38. The extruded resin flows through the runner 38 and is sent to each cavity 32 one after another. The resin flowing into each cavity 32 fills the cavity 32 with the resin while pushing out air in the cavity, and a part of the resin flows into the flow cavity 41 through the through 40. Since the air vent is provided in the cavity 32 and the flow cavity 41 in communication, a part of the resin enters the air vent while extruding air. As a result, bubbles (voids) are not included in the cavity 32.

  In the first embodiment, the resin is injected from one corner of the rectangular cavity, and a symmetrical resin flow is generated in which air is discharged from the air vents at the corners in the diagonal direction and the corners on both sides of the diagonal line. Since the single-sided molding is performed, air in the cavity is smoothly discharged, and bubbles (voids) are not included in the formed package 2.

  After the resin is injected, a curing process is performed to cure the resin. In particular, here, the material cured by the runner 38 is referred to as a runner curing resin 38a, the material cured at the gate 39 portion is referred to as a gate curing resin 39a, and the material cured at the cavity 32 is referred to as a package 2, The material cured at 40 is referred to as a through-curing resin 40a, the material cured at the flow cavity 41 is referred to as a contact prevention body 43, and the material cured at the air vent is referred to as an air vent-curing resin 44. 4 and between the lead 4 and the tab suspension lead 7 is called a resin burr 10. These parts are clearly shown in FIG. 15, FIG. 16, FIG. 18 to FIG.

  The height (thickness) of the contact prevention body 43 is several mm higher than the height (thickness) of the package 2. Therefore, as shown in FIG. 1, when the assembled lead frames 25 are overlapped, the contact frame 43 is interposed between the upper and lower lead frames 25 in the lead frame portion constituting the lead 4 of the semiconductor device 1. Therefore, there is no contact. That is, it is possible to prevent contamination and scratches on the lead 4 portion of the semiconductor device 1 due to contact. In FIG. 1, a region A is a region where the semiconductor device 1 is formed. Therefore, it is important to prevent the mounting surface 16 of the lead 4 in the region A from being contaminated or scratched.

  FIG. 15 is a cross-sectional view showing a package formed by single-sided molding, a contact preventer, etc., FIG. 16 is a cross-sectional view of another cross-section showing a package etc. formed by single-sided molding, and FIG. 18 is a resin sheet used in single-sided molding. FIG. 19 is a plan view of a lead frame on which the package is formed, FIG. 20 is a plan view showing a unit lead frame pattern portion on which the package is formed, and FIG. 21 is a unit lead frame. It is sectional drawing which shows the package etc. of a pattern part.

  Further, since the pressure when the resin is injected into the cavity does not satisfy the load due to mold clamping, the mounting surface 3 of the package 2 is exposed to the mounting surface 3 side of the package 2 as shown in FIG. 4 and the so-called offset structure that is retracted from the mounting surface 16 of the tab suspension lead 7 portion.

  Next, a plating process is performed (S104). This plating process is used when the semiconductor device 1 is mounted. The surface of the lead 4 and the tab suspension lead 7 exposed on the mounting surface 3 of the package 2 is not shown but has a thickness of about 20 to 30 μm, for example. Formed. In this plating process, for example, a solder film made of lead and tin, a solder film made of tin and zinc, and a solder film made of tin and silver are formed. This plating film is not particularly illustrated.

  The lead frame 25 after single-sided molding is stored in a state as shown in FIG. In this case, since the lead frame 25 is of a matrix type, the contact prevention body 43 that is taller than the package 2 is located near one corner of the package 2, so that the upper lead frame 25 is in contact with these contacts. It will be supported by the prevention body 43. As a result, as shown in FIG. 1, the mounting surface 16 of the lead 4 in the region A forming the semiconductor device does not directly contact the lower lead frame 25, and the mounting surface 16 of the lead 4 is contaminated or scratched. Prevention can be achieved.

  Next, as shown in FIG. 22, the gate / flow cavity curing resin is cut by a press machine (tab hanging lead cutting of the same part: S105), the primary lead tip cutting (X-direction extending lead cutting: S106), the first Secondary lead tip cutting [Y direction extending lead cutting: S107] and residual tab hanging lead cutting [air vent cutting: S108] are performed. Each of these cuttings is performed by a composite cutting die attached to a press machine.

  In this cutting step, the lead frame 25 is stored and supplied in a state as shown in FIG.

  FIG. 22 is a perspective view showing a cutting device 60 of the cutting device. The cutting device 60 includes a lower mold base 61 and an upper mold base 62, and columns 63 are provided on the upper surfaces of the four corners of the lower mold base 61, and the columns 63 are disposed on the lower surfaces of the four corners of the upper mold base 62. A fitting portion 64 that is slidably fitted to is fixed. A mounting portion 65 is provided at the center of the upper surface of the lower mold base 61, and a die of a composite cutting mold (not shown) is mounted. A mounting portion 66 is provided in the center of the lower surface of the upper mold base 62, and a punch of a composite cutting mold (not shown) is mounted.

  A guide 67 for guiding the lead frame 25 is provided on the attachment portion 65. The lead frame 25 is supplied upside down to the guide 67 and is pitch-fed from left to right by the guide 67 and a transfer mechanism (not shown). This is because, by punching from the mounting surface 16 side of the lead 4 or the tab suspension lead 7, a cutting burr generated at the time of cutting is generated on the package 2 side, and no cutting burr is generated at the cutting edge on the mounting surface 16 side. This is to prevent troubles during mounting.

  Although not shown, a lifting ram is fixed at the center of the upper surface of the upper mold base 62, and the mounting portion 66 moves up and down by the vertical movement of the lifting ram. Accordingly, a predetermined portion of the lead frame 25 is cut by the die and the punch as the elevating ram is lowered.

  The cutting device 60 incorporates a composite cutting die. This composite cutting die has a plurality of punched portions. As shown in FIG. 23, the punching portion includes a first punching die 70, a second punching die 71, a third punching die 72, and a second punching die along the lead frame transfer direction (from left to right) indicated by arrows. A four punching die 73 is provided.

  The first punching die 70 is a coining portion 70a that allows easy cutting by coining the cut portions of the tab suspension leads 7 protruding from the four corners of the package 2, and a foreign matter guide hole portion 70b for dropping the attached foreign matter. , And a first punching portion 70c that cuts the gate-curing resin and the flow-cavity-curing resin together with the tab suspension leads of the same portion. In the first punched portion 70c, the hatched portion in FIG. 25 is cut. FIG. 26 is a schematic diagram showing a die 75 and a punch 76 for cutting the lead 4 and the tab suspension lead 7. The second punching die 71, in which the punched cut piece falls as it is, cuts the leading end of the primary lead, for example, the lead 4 extending along the X direction. In this cutting, the hatched portion in FIG. 27 is cut.

  The third punching die 72 includes a lead cutting part 72a for cutting the secondary lead tip and a foreign material guide hole 72b for dropping the attached foreign material. In the lead cutting part 72a, the secondary lead tip is cut, for example, the lead 4 extending along the Y direction is cut. In this cutting, the hatched portion in FIG. 28 is cut.

  The fourth punching die 73 cuts the remaining tab suspension lead 7. Accordingly, the air vent extending along the tab suspension lead 7 is also cut. As a result, the package 2 part is separated from the lead frame 25, and the non-lead type semiconductor device 1, that is, the QFN type semiconductor device 1 as shown in FIG. 30 is manufactured. The lead 4 and the tab suspension lead 7 are cut at the base of the package 2. For example, the protruding length of the lead 4 and the tab suspension lead 7 is 0.1 mm or less.

  Further, when the lead 4 and the tab suspension lead 7 are cut, the punch is protruded from the mounting surface side of the package 2 and the lead 4 and the tab suspension lead 7 are cut by the die and the punch. Although a burr (cutting burr) protruding at the cut edge on the side is generated, no cutting burr is generated on the mounting surface side of the package. As a result, not only the appearance of the manufactured non-leaded semiconductor device 1 is improved, but mounting defects due to cutting burrs are not generated.

  In addition, resin burrs are generated between leads at the base of the package or between leads and tab suspension leads. The resin burrs are also cut simultaneously with the cutting of the leads 4 and the tab suspension leads 7. Therefore, the cut surface becomes straight due to the lead, the tab suspension lead and the resin burr.

  FIG. 31 is a cross-sectional view showing another semiconductor device 1 manufactured using a flat lead frame in which a part of the lead 4, the tab 11 and the tab suspension lead are located on the same plane, and FIG. 32 is a cross-sectional view of the other semiconductor device. It is a bottom view of an apparatus. In such a structure, a part of the tab 11 and the tab suspension lead 7 is exposed on the mounting surface 3 of the package 2, so that when the tab 11 and the tab suspension lead 7 are fixed to a mounting substrate such as a wiring substrate, the exposed tab 11 and the tab suspension lead 7. The surface becomes a heat dissipating surface, and there is an actual advantage that the heat of the semiconductor chip 13 can be quickly dissipated out of the package 2. As a result, the semiconductor device 1 can be stably operated. Note that the tab 11 side of the tab suspension lead 7 is formed thin by half etching. Accordingly, the thinned portion is not exposed on the mounting surface 3 of the package 2.

  FIG. 33 shows a QFN type semiconductor device 1 manufactured by using a lead frame in which the tab suspension lead 7 is bent in one step in the middle so that the tab 11 is lifted. In this figure, the right and left sides of the center line are shown in different states so that the structure content can be easily understood.

  The first embodiment has the following effects.

  (1) When the package 2 is formed, the contact prevention body 43 that is thicker than the thickness of the package 2 is formed on the outside of the package 2, so that when the lead frames 25 are overlapped after single-sided molding, the upper and lower lead frames 25 are Since the contact preventer 43 is interposed, the portion that becomes the external electrode terminal of the upper lead frame 25 does not come into contact with the lower package 2, and contamination and scratching of the portion that becomes the external electrode terminal can be suppressed. As a result, a non-leaded semiconductor device with high mounting reliability can be provided. That is, since the plating film on the surface of the external electrode terminal is not contaminated and is not scratched, the mounting reliability of the semiconductor device 1 is increased.

  (2) Since only one contact prevention body 43 is formed per package, even in the case of the matrix type lead frame 25, the amount of resin used is not large. As a result, the injection resin pressure at the time of transfer molding does not need to be so high, and the controllability of the transfer mold does not become difficult. Moreover, the transfer mold apparatus conventionally used can be used as it is.

  (3) According to the above (2), since the amount of the injection resin at the time of transfer molding is not large, there is no occurrence of a short-circuit defect that occurs when the wire 15 falls due to the flow of the resin in the final cavity that is finally fed from the runner. And improved reliability.

  (4) According to the above (2), since only one contact prevention body 43 is formed per package, the pattern size of the unit lead frame pattern 26 can be reduced, and the use efficiency of the lead frame 25 can be increased.

  (5) When the lead 4 and the tab suspension lead 7 are cut, the punch protrudes from the mounting surface 3 of the package 2 and the lead 4 and the tab suspension lead 7 are cut by the die and the punch. Cutting burr does not occur on the mounting surface side. As a result, not only the appearance of the manufactured non-leaded semiconductor device 1 is improved, but also mounting defects due to burrs do not occur.

  (6) Since the tab 11 and the tab suspension lead 7 portion on the tab 11 side have a half-etched structure, the fixing surface of the tab 11 that fixes the semiconductor chip 13 and the connection surface that connects the wire 15 of the lead 4 are the same. Compared to a structure in which the tab suspension lead 7 is raised one step higher and the tab 11 is lifted, the height of the semiconductor device 1 can be reduced.

  (7) With the above (1) to (6), the manufacturing cost of the semiconductor device can be reduced.

(Embodiment 2)
37 to 53 are views relating to a method for manufacturing a semiconductor device according to another embodiment (Embodiment 2). The non-leaded semiconductor device 1 manufactured by the semiconductor device manufacturing method of Embodiment 2 has a structure as shown in FIGS. 37 is a perspective view of the semiconductor device with a part removed, FIG. 38 is a cross-sectional view of the semiconductor device, and FIG. 39 is a bottom view of the semiconductor device.

  The QFN type semiconductor device 1 according to the second embodiment has a structure in which the mounting surface 3 side of the sealing body 2 is covered with a sheet 37a used during transfer molding in the non-lead type semiconductor device 1 according to the first embodiment. The other features are the same as in the first embodiment. The sheet 37 a not only spreads over the entire mounting surface 3 of the sealing body 2, but its outer peripheral edge coincides with the outer peripheral edge by cutting the lead 4, and the resin burr 10 between the lead 4 and the lead 4 or the lead 4 and the tab. It coincides with the outer peripheral edge by cutting the resin burr 10 between the suspension leads 7.

  As a result, the surface of the lead 4 and the tab suspension lead 7 exposed on the mounting surface 3 is covered and protected by the sheet 37a, and the surface of the lead 4 and the tab suspension lead 7 is scratched or foreign matter adheres. There is nothing.

  In the semiconductor device 1 according to the second embodiment, a plating film 80 is formed on the surfaces of the leads 4 and the tab suspension leads 7 as shown in FIG. The plating film 80 is not particularly limited. For example, the plating film 80 is composed of a solder film made of lead and tin, a solder film made of tin and zinc, a solder film made of tin and silver, or a palladium film not using lead.

  Therefore, until the sheet 37a is peeled off, the plating film 80 is not scratched or contaminated by foreign matter. When the sheet 37a is peeled off and mounted on the wiring board, the result is as shown in FIG. If the sheet 37a is separated and immediately mounted on the wiring board constituting the electronic device, the lead 4 and the tab suspension lead 7 are securely connected to the wiring board and the connection reliability is high. As a result, an electronic device with excellent quality and high reliability can be manufactured.

  Next, the manufacture of the semiconductor device according to the second embodiment will be described. 40 to 53 are views relating to the method of manufacturing the semiconductor device of the second embodiment.

  FIG. 40 is a flowchart showing a method of manufacturing a QFN type semiconductor device according to the second embodiment. The semiconductor device 1 is manufactured through steps 201 to 209.

  That is, after starting the work, selective plating on the lead frame (S201), chip bonding (S202), wire bonding (S203), mold (S204), notch processing (S205), gate / flow cavity curing resin cutting (S206) ), Primary lead tip cutting (S207), secondary lead tip cutting (S208), and remaining tab suspension lead cutting (S209), and the operation is completed. The notch processing (S205), gate / flow cavity hardening resin cutting (S206), primary lead tip cutting (S207), secondary lead tip cutting (S208), residual tab suspension lead cutting (S209) are combined cutting. Cutting with a mold.

  In the second embodiment, the cutting process using the composite cutting die has a notch process (S205). In this notch processing, in order to improve the cutting property of the tab suspension lead 7 protruding from the peripheral edge of the sealing body 2, a V-groove is formed in the cut portion, and when the tab suspension lead 7 is subsequently cut, This is because stress concentration is generated at the bottom of the V groove to facilitate cutting. Although not shown, a notch portion is provided in the first station of the composite cutting die. The notched portion includes a die having a V-groove on the surface supporting the tab suspension lead 7 and a punch having a tip corresponding to the V-groove of the die, and the tab suspension lead 7 is crossed by the punch and the die. Thus, a V-groove notch is formed over the entire width. Note that the notch is not necessarily limited to the V-groove, and a notch having another structure may be used as long as the cutting performance is improved.

  In the second embodiment, unlike the first embodiment, (1) a plated film is selectively formed on the lead frame before chip bonding, and (2) a notch is first formed in a cutting process by a composite cutting die performed after molding. (3) In addition, in the transfer mold (mold) using a sheet, the sheet uses an adhesive sheet, and after the leads and tab suspension leads are cut, the mounting surface side of the sealed body And (4) mounting the semiconductor device by removing the sheet before mounting. Therefore, in the following description, the description of the same part as in the first embodiment will be omitted.

  In the manufacture of the semiconductor device 1 of the second embodiment, as shown in FIG. 41, a lead frame 25 having the same matrix configuration as that of the first embodiment is prepared.

  Next, as shown in FIG. 42, a plating process is performed on the lead 4 and the tab suspension lead 7 serving as the mounting surface to form a plating film 80 (plating: S201). In FIG. 42, the portion where the plating film 80 is formed is shown by hatching. The plating film 80 is not particularly limited. For example, the plating film 80 is composed of a solder film made of lead and tin, a solder film made of tin and zinc, a solder film made of tin and silver, or a palladium film not using lead. FIG. 42 shows the back surface of the lead frame 25. Further, the tab 11 and the portion near the tab 11 of the tab suspension lead 7 that supports the tab 11 are thinned by half-etching the back side. This portion is a portion covered with a sealing body, and no plating film is formed.

  Next, the semiconductor chip 13 is fixed on the tab 11 (chip bonding: S202), and the electrode 14 of the semiconductor chip 13 and the inner end portion of the lead 4 are electrically connected by the conductive wire 15 (wire bonding: wire bonding: S203) (see FIG. 43).

  Next, as shown in FIG. 44, single-sided molding is performed on the assembled lead frame 25 to form a sealed body (package) 2 (mold: S204). In this single-sided molding, single-sided molding is performed by a sheet molding method in which a sheet is interposed between the lead frame 25 and the upper mold 36 as in the first embodiment.

  However, in this sheet mold, a sheet 37a having adhesiveness is used as the sheet. Therefore, the sheet 37a remains attached to the mounting surface side of the sealing body 2 even after molding. In the second embodiment, although not shown, the sheet 37a is cut with substantially the same dimensions as the lead frame 25. Also in this transfer mold, the contact prevention body 43 higher (thick) than the height (thickness) of the sealing body 2 is formed as in the case of the first embodiment.

  45 is a plan view of a lead frame in which a package, a contact prevention body, etc. are formed by single-sided molding, FIG. 46 is a plan view showing a unit lead frame pattern portion in which the package is formed, and FIG. 47 is a package in the unit lead frame pattern portion FIG.

  The lead frame 25 after single-sided molding is stored in a state as shown in FIG. In this case, since the lead frame 25 is of a matrix type, the contact prevention body 43 that is taller than the package 2 is located near one corner of the package 2, and the upper lead frame 25 is placed by the contact prevention body 43. It will be supported. As a result, the external force due to the contact does not act on the surfaces of the lead 4 and the tab suspension lead 7 in the region where the semiconductor device is formed. In the case of the second embodiment, since the lead 4 and the tab suspension lead 7 are protected by the sheet 37a, the surface of the lead 4 and the tab suspension lead 7 is further damaged or contaminated by foreign matter adhesion. Is prevented. FIG. 49 is a cross-sectional view showing the two-stage lead frame 25 in a stacked state showing the internal state.

  Next, using the press machine used in the first embodiment and a composite cutting die in which notching is incorporated in the first station, notching (V groove: S205), gate / flow cavity curing resin cutting [same as above] Partial tab hanging lead cutting: S206], primary lead tip cutting [X direction extending lead cutting: S207], secondary lead tip cutting [Y direction extending lead cutting: S208], residual tab hanging lead cutting [ Air vent cutting: S209]. In this cutting step, the lead frame 25 is stored and supplied in the state shown in FIG.

  The lead frame 25 is turned upside down and sandwiched between the lower mold and the upper mold of the composite cutting mold, and the cutting molding process is performed. FIG. 50 is a schematic diagram showing a state in which a notch (V groove) 85 is formed in the tab suspension lead 7 by notching (S205) (see FIG. 52).

  In FIG. 51, the dotted portions are cut by the punch 76 (S206). This cut portion is a portion where the notch (V groove) 85 is provided in the tab suspension lead 7, and the bottom of the V groove is a cutting line. FIG. 52 shows a cut state by the die 75 and the punch 76. The punch 76 is guided by a guide 86. Even in this cutting, the sheet 37a is stuck to one surface of the lead frame 25. Cutting is performed by the punch 76 in the direction in which the sealing body 2 exists from the surface of the sheet 37a. As a result, the edge (outer peripheral edge) on the mounting surface 16 side of the sealing body 2 becomes a rounded edge and does not become an edge with protruding burrs, and the mounting state is impaired by the burrs during mounting. There is no.

  Next, although not shown, primary lead tip cutting (S207), secondary lead tip cutting (S208), and residual tab suspension lead cutting (S209) are performed as in the first embodiment. As a result, the package 2 part is detached from the lead frame 25, and the non-lead type semiconductor device 1, that is, the QFN type semiconductor device 1 as shown in FIGS. 37 to 39 is manufactured. The lead 4 and the tab suspension lead 7 are cut at the base of the package 2. For example, the protruding length of the lead 4 and the tab suspension lead 7 is 0.1 mm or less.

  Further, when the lead 4 and the tab suspension lead 7 are cut, the punch is protruded from the mounting surface side of the package 2 and the lead 4 and the tab suspension lead 7 are cut by the die and the punch. Although a burr (cutting burr) protruding at the cut edge on the side is generated, no cutting burr is generated on the mounting surface side of the package. As a result, not only the appearance of the manufactured non-leaded semiconductor device 1 is improved, but mounting defects due to cutting burrs are not generated.

  In addition, resin burrs are generated between leads at the base of the package or between leads and tab suspension leads. The resin burrs are also cut simultaneously with the cutting of the leads 4 and the tab suspension leads 7. Therefore, the cut surface becomes straight due to the lead, the tab suspension lead and the resin burr.

  In the semiconductor device 1 according to the second embodiment, since the sheet 37 a is attached to the mounting surface side of the sealing body 2, the surface of the lead 4 and the tab suspension lead 7 that exposes the surface on the mounting surface of the sealing body 2. Is protected by the sheet 37a and is prevented from being damaged or contaminated by foreign matter.

  Therefore, the sheet 37a is shipped with the sheet 37a attached, or the sheet 37a is peeled off before shipment and stored in a tray or the like. In addition, it is desirable to attach the sheet 37a immediately before mounting in order to improve mounting reliability.

  54 (a) and 54 (b) show that the resin burrs 10 or the portion extending from the resin burrs 10 to the sealing body 2 is chipped in the gate / flow cavity hardening resin cutting [cutting the tab hanging lead of the same part] in the cutting and forming process. 90) It is the figure which showed the example. However, if the gate / flow cavity curing resin cutting is performed with the sheet 37a attached as in the second embodiment, the sheet 37a acts as a strength member, so that the resin burr 10 portion or the resin burr 10 extends from the resin burr 10 to the sealing body 2. No chipping occurs in the part.

  Further, the damaged fine resin generated at the time of cutting remains stuck to the sheet 37a, and the damaged fine resin does not fall off during conveyance or the like, and the surroundings and the machine are not soiled. Further, since the damaged fine resin is removed while being attached to the sheet 37a when the sheet 37a is peeled off, the semiconductor device 1 and the surrounding work environment are not contaminated.

  53A and 53B show an example in which the sheet 37a is peeled (separated) from the semiconductor device 1. FIG. For example, as shown in FIG. 53 (a), the semiconductor device 1 is housed in the housing dent 92 of the work station 91 with the inside upside down. The housing recess 92 has a vacuum suction recess 93 for increasing the vacuum suction force at the bottom, and a suction hole 94 connected to the vacuum suction mechanism at the bottom of the vacuum suction recess 93.

  Therefore, the semiconductor device 1 housed in the housing recess 92 is vacuum-sucked and held in the housing recess 92 by operating the vacuum suction mechanism. Further, the sheet 37a of the semiconductor device 1 is vacuum-sucked and held by the nozzle 95 that can vacuum-suck, and in this state, the nozzle 95 is moved up and away from the semiconductor device 1 as shown in FIG. Thereby, the sheet 37 a can be peeled off from the sealing body 2 and separated from the semiconductor device 1.

  Next, after the sheet 37a held by the nozzle 95 is carried to a predetermined location and discarded, the nozzle 95 is again returned to the accommodation recess 92 and lowered, and the semiconductor device 1 is again vacuum-sucked and held by the nozzle 95 to the predetermined location. Carry it, turn it over again, carry it, mount it on a predetermined wiring board, or store it in a shipping tray or the like.

  The means for peeling the sheet 37a from the sealing body 2 of the semiconductor device 1 may be another method.

  The second embodiment also has some of the effects of the first embodiment. In the second embodiment, since the sheet 37a is attached to one surface of the lead frame 25 in the semiconductor device manufacturing method, even if the lead frame 25 is stacked in a plurality of stages, the sheet 37a is interposed in the overlapping portion. The portion that becomes the external electrode terminal of the upper lead frame 25 is not in direct contact with the lower package 2, and contamination and scratching of the portion that becomes the external electrode terminal can be suppressed. Further, even if the lead frames 25 are stacked, the contact prevention body 43 is present, so that the portion serving as the external electrode terminal is not damaged without application of external force due to contact with the lower sealing body.

  As a result, since the reliability of mounting the non-lead type semiconductor device is increased in the manufacture of the electronic device, an electronic device having excellent quality and high reliability can be manufactured.

  Although the invention made by the present inventor has been specifically described based on the embodiment, the present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the invention. Nor.

  In the embodiment, the plating process is performed after the single-sided molding, but the plating process (pre-plating) may be performed after the lead frame is formed. In this case, for example, a palladium plating film may be formed as a plating film not using lead. Even in this case, after the single-sided molding, it is possible to prevent the surface of the portion to be the external electrode terminal from being contaminated and scratched.

  In the above-described embodiment, the example in which the present invention is applied to the manufacture of the QFN type semiconductor device has been described. However, the present invention can be applied to the manufacture of the SON type semiconductor device in the same manner, and the same effect is obtained. Can have. The present invention can be applied to at least a non-lead type semiconductor device.

1. Semiconductor device (non-lead type semiconductor device)
2 ... Sealed body (package)
2a ... Rising edge 3 ... Mounting surface 4 ... External electrode terminal (lead)
5 ... Slope 6 ... Upper surface 7 ... Tab suspension lead 10 ... Resin burr 11 ... Tab 12 ... Bonding material 13 ... Semiconductor chip 14 ... Electrode 15 ... Wire 16 ... Mounting surface 20 ... Wiring board 21 ... Electrode (land)
22 ... Bonding material 25 ... Lead frame 26 ... Unit lead frame patterns 27a-27c ... Guide holes 28, 29 ... Ejector pin holes 30 ... Frame part 31 ... Slit 32 ... Cavity 33 ... Opening 34 ... Hole 35 ... Lower mold 35a , 35b ... mating surface (parting surface)
36 ... Upper mold 37, 37a ... Sheet 38 ... Runner 39 ... Gate 40 ... Through 41 ... Flow cavity 42 ... Pot (Cull)
43 ... Contact preventer 44 ... Air vent curing resin 50 ... Wiring board 51 ... Bonding material (solder)
55 ... Fillet 56 ... Foreign object 60 ... Cutting device 61 ... Lower mold base 62 ... Upper mold base 63 ... Column 64 ... Fitting portion 65, 66 ... Mounting portion 67 ... Guide 70 ... First punching die 71 ... Second punching Punching die 72 ... Third punching die 73 ... Fourth punching die 75 ... Die 76 ... Punch 80 ... Plating film 85 ... Notch (V groove)
86 ... Guide 90 ... Chipped portion 91 ... Station 92 ... Housing recess 93 ... Vacuum suction recess 94 ... Suction hole 95 ... Nozzle

Claims (14)

A frame, a tab positioned inward of the frame, a plurality of tab suspension leads extending from the frame toward the tab and supporting the tab at a tip portion, and the tab from the frame A step of preparing a matrix type lead frame in which a plurality of unit lead frame patterns including a plurality of leads extending in the vertical and horizontal directions are arranged;
Fixing a semiconductor chip on one side of the tab;
Connecting the electrode of the semiconductor chip and the inner end of the lead with a conductive wire;
The semiconductor chip, the wire, and the inner end portion of the lead are covered with a sealing body made of an insulating resin by single-sided molding, and the leads and the tab suspension leads are exposed on the mounting surface of the sealing body during the single-sided molding. Process,
A cutting step of cutting the lead or the tab suspension lead;
A method of manufacturing a semiconductor device having
A method of manufacturing a semiconductor device comprising: forming one contact prevention body thicker than the sealing body outside the sealing body during the one-side molding, and cutting and removing the contact prevention body in the cutting step. .   At the time of forming the sealing body, the contact prevention body is formed on the side opposite to the resin injection side for forming the sealing body, and air escape when forming the sealing body is the formation of the contact prevention body. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the method is performed from a side of the sealing body forming portion intersecting a portion and a line connecting the resin injection side and the contact prevention body forming portion.   At the time of the single-sided molding, a sheet that is more flexible than the lead is disposed between the upper and lower molds of the mold, and the lead frame is stacked on the sheet, and the sealing body is placed on the lead frame surface side where the sheet is not stacked. The method of manufacturing a semiconductor device according to claim 1, wherein:   2. The method of manufacturing a semiconductor device according to claim 1, wherein after the one-side molding, plating is performed to form a plating film for mounting at a predetermined portion of the matrix type lead frame.   2. The method of manufacturing a semiconductor device according to claim 1, wherein in the cutting step, a punch is protruded from a mounting surface side of the sealing body, and the lead and the tab suspension lead are cut by a die and the punch.   2. The method of manufacturing a semiconductor device according to claim 1, wherein plating is performed in a state before the semiconductor chip is fixed, and a plating film for mounting is formed at a predetermined position of the matrix type lead frame.   The method of manufacturing a semiconductor device according to claim 6, wherein a palladium plating film is formed by the plating.   After forming the sealing body and the contact prevention body on each unit lead frame pattern portion of the matrix type lead frame, the upper matrix type lead frame overlaps with each contact prevention body of the lower matrix type lead frame. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the matrix type lead frame is stored and supplied in a state where a plurality of the matrix type lead frames are stacked. A frame, a tab positioned inward of the frame, a plurality of tab suspension leads extending from the frame toward the tab and supporting the tab at a tip portion, and the tab from the frame A step of preparing a matrix type lead frame in which a plurality of unit lead frame patterns including a plurality of leads extending in the vertical and horizontal directions are arranged;
Fixing a semiconductor chip on one side of the tab;
Connecting the electrode of the semiconductor chip and the inner end of the lead with a conductive wire;
The semiconductor chip, the wire, and the inner end portion of the lead are covered with a sealing body made of an insulating resin by single-sided molding, and the leads and the tab suspension leads are exposed on the mounting surface of the sealing body during the single-sided molding. A process of
A cutting step of cutting the lead or the tab suspension lead;
A method of manufacturing a semiconductor device having
During the one-side molding, a sheet that is more flexible than the leads is disposed between the upper and lower molds of the mold, and one surface of the lead frame is overlaid on the sheet, and the other side of the lead frame that does not overlap the sheet Forming a sealing body, further forming one contact prevention body thicker than the sealing body outside the sealing body,
In the cutting step, the lead and the tab suspension lead are cut with the sheet attached , and the contact preventer is cut and removed .   10. The method of manufacturing a semiconductor device according to claim 9, wherein plating is performed before the one-sided molding, and a plating film for mounting is formed at a predetermined position of the matrix type lead frame.   After the sealing body is formed on each unit lead frame pattern portion of the matrix type lead frame, a plurality of the matrix type lead frames are stacked with the sheet attached, and the matrix type lead frame is stored in this stacked state. The method for manufacturing a semiconductor device according to claim 9, wherein supply is performed.   The method for manufacturing a semiconductor device according to claim 9, wherein the semiconductor device is manufactured by cutting the lead or the tab suspension lead and then peeling the sheet bonded to the sealing body or the lead. .   The sheet is vacuum-sucked and held with a nozzle that can be vacuum-sucked while the sealing body is held by vacuum suction, and then the nozzle is moved away from the sealing body to separate the sheet from the sealing body. A method for manufacturing a semiconductor device according to claim 9. A frame, a tab positioned inward of the frame, a plurality of tab suspension leads extending from the frame toward the tab and supporting the tab at a tip portion, and the tab from the frame A step of preparing a matrix type lead frame in which a plurality of unit lead frame patterns including a plurality of leads extending in the vertical and horizontal directions are arranged;
Fixing a semiconductor chip on one side of the tab;
Connecting the electrode of the semiconductor chip and the inner end of the lead with a conductive wire;
The semiconductor chip, the wire, and the inner end portion of the lead are covered with a sealing body made of an insulating resin by single-sided molding, and the leads and the tab suspension leads are exposed on the mounting surface of the sealing body during the single-sided molding. Process,
A method of manufacturing an electronic device by surface-mounting the semiconductor device on a predetermined wiring board after manufacturing the semiconductor device by a cutting step of cutting the lead or the tab suspension lead,
During the single-sided molding, a sheet that is more flexible than the lead is disposed between the upper and lower molds of the mold, and the lead frame is overlaid on the sheet, and the sealing body is placed on the lead frame surface side where the sheet is not overlaid forming a further the sealing body outside the thick contact prevention member than the sealing member and one formed of, in the cutting step, the cut leads and said tab suspending lead in leaving the said sheet, further by cutting and removing the contact prevention member, to manufacture the semiconductor device,
Then, after separating the sheet from the sealing body, the semiconductor sheet is surface-mounted on the wiring board.

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