JP2005209999A - Semiconductor device and lead frame, and method for manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low cost semiconductor device and a lead frame capable of enhancing a solder adhesive property of the tip of a lead, and to provide a method for manufacturing the semiconductor device. <P>SOLUTION: A plurality of leads 3 are provided at the side surface of a sealing resin 1. The tip 3a of the lead 3 is bent upward by a half blanking construction method, and a step 3c is formed on the lower surface 3b of the lead 3. A sag surface 3e, a shearing surface 3f, a fracturing surface 3g, and a cutting burr 3h are formed on the tip surface of the lead 3 from the lower surface 3b side to the upper surface 3d side in this order. A plating coat is formed on the lower surface 3b including the step 3c, the upper surface 3d, the side surface, and the sag surface 3e of the lead 3. The solder connection of the lead 3 and an electrode of a packaging substrate forms a solder fillet on the lower surface 3b including the step 3c and the side surface of the lead. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sealing resin for sealing a semiconductor chip, a semiconductor device having a plurality of leads on the outer edge of the sealing resin, a lead frame used in the semiconductor device, and a semiconductor device using the lead frame It relates to a manufacturing method.

  As a semiconductor device provided with a sealing resin for sealing a semiconductor chip and a plurality of leads at the outer edge of the sealing resin, for example, a leadless type (SON; JEITA ED-7311 having a short lead portion protruding from the sealing resin) IC package called -13A, FQN; JEITA ED-7111-22, etc., or a gull wing type IC package in which the lead protruding horizontally from the sealing resin is bent downward and further bent horizontally. is there.

  In such a method of manufacturing a semiconductor device, after mounting a semiconductor chip on a lead frame and performing a resin sealing process on the semiconductor chip, an exterior process such as removal of a sealing resin burr and solder plating is performed. A portion of the lead frame corresponding to the lead tip is cut to separate the semiconductor device from the lead frame. In the gull wing type semiconductor device, a forming process for bending the lead into a predetermined shape is further performed.

  As described above, since the solder plating process is performed on the leads before the semiconductor device is separated from the lead frame, no plating film is formed on the leading end surface of the lead after the semiconductor device is separated from the lead frame. When mounted on a substrate or the like, there was a problem that the solder wettability of the lead tip was poor. Such a problem is particularly a problem in a leadless type semiconductor device.

Various conventional techniques have been disclosed in order to form a plating film on the leading end portion of the lead for such a problem.
For example, in Patent Document 1, as shown in FIG. 24, a concave portion 53 having a bottom portion having a depth of about 2/3 of the lead thickness and a width of about 1 mm at a tip portion of the outer lead 51 at the time of lead formation. A lead frame for a semiconductor device is disclosed in which the outer lead 51 is cut at the cutting position 55 so that plating is attached to the cut surface that is the lead tip. FIG. 24 is a side view of the outer lead before cutting. Etching or coining is mentioned as a method of forming a recess in a portion that becomes the tip of the outer lead.

  Further, Patent Document 2 discloses a first step of forming a groove in a lead frame material before lead processing at a portion to be a terminal of a lead and on the board mounting surface side, and a lead frame formed with this groove. A second step of forming solder plating on the front, back, and side surfaces of the material, and a third step of cutting the lead-plated lead frame groove into a lead shape are provided. A method for manufacturing a resin-encapsulated semiconductor device is disclosed. Half etching is mentioned as a method of forming the groove.

However, as shown in Patent Documents 1 and 2, in order to form a recess or groove in a lead by etching (including half-etching), a resist for defining a region for selectively removing the lead in the thickness direction There is a problem that man-hours such as coating processing, exposure processing, and development processing are required, resulting in an increase in manufacturing cost.
In addition, when concave portions are formed in the leads by coining, there is a problem that the lead width of the concave portion forming portion is increased and short-circuiting between the leads is easily caused.

Further, in Patent Document 3, as shown in FIG. 25, a semiconductor chip is mounted on a stage of a lead frame in which leading ends of leads 57 are connected to each other with a connecting member (not shown), and sealed with resin. Then, the semiconductor device manufacturing method includes a step of bending and forming the lead 57 by cutting and removing the connecting member. When the connecting member is cut and removed, the leading end portion 57a of the lead 57 is thinly cut ((A )), And bending the lead 57, the tip 57a of the lead 57 is pressed and thinned (see (B) and (C)). FIG. 25 shows a lead tip, (A) is a plan view before press processing, (B) is a plan view after press processing, and (C) is a side view after press processing.
However, when the tip of the lead is thinly processed by pressing, there is a problem that the tip position of the lead cannot be accurately determined.

Further, in Patent Document 4, a lead frame in which a groove is previously formed in a portion corresponding to the tip of the external lead is used, or a groove is formed in a portion corresponding to the tip of the external lead from above before solder plating. Thus, a solder-plated portion is formed on the upper surface of the tip of the external lead of the semiconductor device. As a method for forming the groove, a method using half-etching and a die added with a punch for V-notch processing is cited.
However, as described above, when the step of forming the groove by half etching is included, there is a problem in that the manufacturing cost increases.
In addition, when a mold having a punch for V-notch processing is used, there is a problem that the formation position of the V-shaped groove cannot be accurately determined.

Further, in Patent Document 5, as shown in FIG. 26, a notch 61 is provided on one side surface 59a of the lead 59 in the thickness direction of the lead 59, and the notch 61 is cut after plating (refer to a one-dot chain line). A method of manufacturing a semiconductor device having a front end portion is disclosed. FIG. 26 is a plan view of the lead before cutting. As a method for forming the cut portion 61, etching or pressing is cited.
However, when etching is used as a method for forming the cut portion, there is a problem in that the manufacturing cost increases as described above.
In addition, when the cut portion is formed by pressing, there is a problem that the lead is deformed or cut to cause a short between leads or a short between leads.

Further, in Patent Document 6, a V-shaped notch is formed at a position corresponding to the tip of the lead, and after the exterior treatment is performed on the lead frame after the resin sealing is finished, an area outside the prescribed cutting line is disclosed. Then, the outer lead is separated from the lead frame, and then, before or after the outer lead is formed into a predetermined shape, a notch portion is formed on the leaded surface on the cutting line. Thereafter, a lead processing method for a semiconductor device is disclosed in which an outer lead is cut along a cutting line to leave a plating film due to a notch mark on a lead tip surface.
According to this lead processing method, the formation position of the lead tip surface can be formed precisely and inexpensively, but the portion corresponding to the V-shaped notch in the mold for forming the V-shaped notch has an acute angle. Therefore, there is a problem that the life of the mold is short, and as a result, the manufacturing cost increases.

Further, in Patent Document 7, as shown in FIG. 27, the tip of the outer connection outer lead 63 cut by a dedicated die and bent into a gull wing shape is placed on the placement portion placed on the pad. A semiconductor device is disclosed in which an inclined surface 65 for reducing the lead thickness of the cut surface is formed. FIG. 27 is a side view of the distal end portion of the outer lead. In Patent Document 7, half etching is cited as a method of forming the inclined surface 65.
However, as described above, when the step of forming the groove by half etching is included, there is a problem in that the manufacturing cost increases.
Japanese Patent No. 2936769 JP-A-6-334090 Japanese Patent Laid-Open No. 5-144988 Japanese Patent Laid-Open No. 7-30042 Japanese Patent Laid-Open No. 7-30043 JP-A-8-172153 Japanese Patent Laid-Open No. 9-232499

  An object of the present invention is to provide a semiconductor device, a lead frame, and a method for manufacturing a semiconductor device that are inexpensive and can improve solder adhesion at the tip of a lead.

A first aspect of the semiconductor device of the present invention is a semiconductor device comprising a sealing resin for sealing a semiconductor chip and a plurality of leads on the outer edge of the sealing resin, wherein the leading end of the lead is half-punched It is bent upward by the construction method.
According to a second aspect of the semiconductor device of the present invention, the leading end of the lead is bent downward by a half punching method.
In the claims of the present application and in the present specification, the half punching method refers to a method of making a convex shape with the hole being stopped halfway. In the half punching method, the area viewed from the upper surface of the convex portion forming region is substantially the same before and after the processing.

In the tip surface of the lead of the semiconductor device of the present invention, a sagging surface may be formed on the upper surface side, or a sagging surface may be formed on the lower surface side.
An example of a semiconductor device to which the semiconductor device of the present invention is applied is a leadless type. However, the semiconductor device to which the present invention is applied is not limited to the leadless type, and can also be applied to other semiconductor devices such as a gull-wing type semiconductor device.

  The lead frame of the present invention is used in a semiconductor device having a sealing resin for sealing a semiconductor chip and a plurality of leads on the outer edge of the sealing resin, and corresponds to the leading end of the lead after cutting. The part to be formed is formed in a convex shape upward or downward by a half punching method.

  A manufacturing method of a semiconductor device of the present invention is a manufacturing method for manufacturing a semiconductor device having a sealing resin for sealing a semiconductor chip and a plurality of leads on an outer edge portion of the sealing resin, after cutting After using a lead frame in which a portion corresponding to the tip of the lead is formed in a convex shape upward or downward by a half-punch method, a semiconductor chip is mounted on the lead frame and subjected to resin sealing treatment and plating treatment And cutting the protruding portion of the lead frame to separate the semiconductor device from the lead frame.

  In the method of manufacturing a semiconductor device of the present invention, when cutting the convex portion, the first cutting blade having a blade thickness on the sealing resin side with respect to the cutting position and the sealing resin with respect to the cutting position An example in which a second cutting blade having a blade thickness on the opposite side is used and the first cutting blade is pressed against the lead frame from the back surface side and the second cutting blade is pressed from the top surface side to cut the convex portion. Can be mentioned.

In the first aspect of the semiconductor device of the present invention, the leading end of the lead is bent upward by a half punching method, and in the second aspect, the leading end of the lead is bent downward by a half punching method. Therefore, the plating film formation area at the lead tip can be increased, and the solder adhesion at the lead tip can be improved. Furthermore, since the tip of the lead is bent by a half-punch method, the area seen from the top surface of the lead tip is almost the same as before being bent, and the lead tip area is the same as when it is thinned by pressing. It does not become large, and there is no problem of short circuit between adjacent leads. Further, the mold used in the half-cutting method does not have to have a thin blade (acute angle portion) like a mold for forming a V-shaped notch, so that consumption is low and productivity is high.
Furthermore, in the second aspect, since the leading end of the lead is bent downward, when the second aspect is applied to a leadless type semiconductor device, the leading end of the lead is disposed below the bottom of the package. It is possible to prevent the soldering from being affected even if a small dust or the like enters the package when the semiconductor device is mounted.

  If a sag surface is formed on the upper surface side of the leading end surface of the lead of the semiconductor device of the present invention, when the semiconductor device is separated from the lead frame, a blade thickness is provided on the sealing resin side with respect to the cutting position. Lead using a first cutting blade pressed from the back side of the lead and a second cutting blade having a blade thickness on the side opposite to the sealing resin with respect to the cutting position and pressed from the upper surface side of the lead Can be formed. As a result, it is not necessary to use a thin cutting blade as a cutting blade that presses from the upper surface side of the lead when cutting a leadless type semiconductor device from the lead frame. The life of the blade can be extended, and the manufacturing cost can be reduced.

  Further, if a sag surface is formed on the lower surface side of the lead end surface of the lead of the semiconductor device of the present invention, the solder wettability of the lead end portion can be improved by plating remaining on the surface of the sag surface.

  Further, even when the semiconductor device of the present invention is applied to a leadless type semiconductor device, it is inexpensive and can improve solder adhesion at the tip of the lead.

  In the lead frame of the present invention, the portion corresponding to the leading end of the lead after cutting is formed in a convex shape upward or downward by a half punching method, so that it can be used for the semiconductor device of the present invention and is inexpensive. In addition, a semiconductor device with improved solder adhesion at the tip of the lead can be realized.

  In the method for manufacturing a semiconductor device of the present invention, the lead frame of the present invention is used, a semiconductor chip is mounted on the lead frame, subjected to resin sealing treatment and plating treatment, and then the convex portion of the lead frame is cut to obtain a semiconductor. Since the step of separating the device from the lead frame is included, the semiconductor device of the present invention with improved solder adhesion at the lead tip can be manufactured at low cost.

  Furthermore, in the manufacturing method of the semiconductor device of the present invention, when cutting the convex portion, the first cutting blade having a blade thickness on the sealing resin side with respect to the cutting position and the sealing resin with respect to the cutting position A second cutting blade having a blade thickness on the opposite side is used, the first cutting blade is pressed against the lead frame from the back surface side, and the second cutting blade is pressed from the top surface side to cut the convex portion. In particular, when cutting a leadless type semiconductor device from the lead frame, it is not necessary to use a thin cutting blade that presses against the upper surface of the lead frame. The lifetime of the cutting blade can be extended, and the manufacturing cost can be reduced.

  1A and 1B are diagrams showing an embodiment of a semiconductor device, where FIG. 1A is a plan view, FIG. 1B is a side view seen from the A direction, FIG. 1C is a side view seen from the B direction, and FIG. FIG. 5E is an enlarged view of a portion surrounded by a broken-line circle in FIG. In this embodiment, the first embodiment of the semiconductor device of the present invention is applied to a leadless type SON.

  A plurality of leads 3 are provided on the side surface of the sealing resin 1 for sealing the semiconductor chip. A part of the lead 3 is exposed on the bottom surface of the sealing resin 1. For example, the thickness of the lead 3 is 0.13 mm (millimeter), the width dimension is 0.2 mm, the protruding length from the sealing resin 1 is 0.2 mm, and the distance between the adjacent leads 3 is 3 mm. It is. The tip 3 a of the lead 3 is bent upward by, for example, half the thickness of the lead 3 by a half-cutting method, and a step 3 c is formed on the lower surface 3 b of the lead 3. The thickness and the width dimension of the distal end portion 3a are substantially the same as the base end portion of the lead 3, that is, substantially the same as before the lead 3 is bent by the half punching method.

  A sag surface 3e, a shear surface 3f, a fracture surface 3g, and a cutting burr 3h are formed on the tip surface of the lead 3 in order from the lower surface 3b side to the upper surface 3d side. In the lead 3, a plating film (not shown) is formed on the lower surface 3b, the upper surface 3d, the side surface, and the sag surface 3e including the step portion 3c. The shearing surface 3f may or may not be formed with a plating film. Further, the cutting burr 3h may or may not be formed.

FIG. 2 is a cross-sectional view showing a lead portion in a state where this embodiment is mounted on a mounting substrate. FIG. 2A shows a lead tip surface when a plating film is not formed on the shearing surface of the lead tip surface. The case where a plating film is formed on the shearing surface is shown.
When the SON is mounted on the mounting substrate 5 and the lead 3 and the electrode (not shown) of the mounting substrate 5 are soldered, solder fillets 7 are formed on the lower surface 3b and the side surface including the stepped portion 3c of the lead 3 (( A) and (B)). Further, as shown in (B), when a plating film is formed on the shearing surface 3f of the tip surface of the lead 3, the solder fillet 7 is also formed on the shearing surface 3f.

As described above, the tip 3a of the lead 3 is bent upward and the step 3c is formed on the lower surface 3b of the lead 3, thereby increasing the plating film formation area at the lead tip. Solder adhesion can be improved.
Further, in this embodiment, since the sag surface 3e is formed on the lower surface 3b side at the leading end surface of the lead 3, the plating film forming area at the leading end of the lead can be further increased.
Furthermore, since the cutting burr 3h is formed on the upper surface 3d side at the tip surface of the lead 3, variation in the mounting height can be suppressed.

  3A and 3B are diagrams showing an embodiment of the lead frame, in which FIG. 3A is a plan view and FIG. 3B is a cross-sectional view taken along the line AA in FIG. FIG. 4 is a schematic process cross-sectional view for explaining an embodiment of the manufacturing method, and shows a process of manufacturing the semiconductor device shown in FIG. 1 using the lead frame shown in FIG. First, an embodiment of the lead frame will be described with reference to FIG.

The lead frame 9 is formed with a plurality of sets each including a die pad 11 for mounting a semiconductor chip and a plurality of leads 3 provided close to the die pad 11. In the lead 3, a portion corresponding to the leading end of the lead after cutting is formed in a convex shape upward by a half punching method, and a concave portion 13 is formed in the back surface 3b. In (A), illustration of the convex part corresponding to the recessed part 13 is abbreviate | omitted.
In the formation region of the recess 13, the area viewed from the upper surface is substantially the same before and after processing, and the volume of the recess and the protrusion is approximately the same. In this embodiment, for example, the concave portion 13 is formed by bending upward by a half dimension of the thickness of the lead 3.

An embodiment of the manufacturing method will be described with reference to FIG.
The semiconductor chip 15 is mounted on the die pad 11 of the lead frame 9 described with reference to FIG. 3, and the electrode pad (not shown) of the semiconductor chip 15 and the lead 3 are electrically connected by the bonding wire 17 ((a )reference).
After the semiconductor chip 15 and the bonding wire 17 are resin-sealed with the sealing resin 1, exterior processing such as removal of the sealing resin burr and solder plating is performed (see (b)). At this time, a plating film is also formed on the inner wall of the recess 13 of the lead frame 9.

A male cutting blade 19 having a blade thickness on the sealing resin 1 side with respect to the cutting position corresponding to the recess 13 of the lead 3 and a female having a blade thickness on the opposite side of the sealing resin 1 with respect to the cutting position. Using the mold cutting blade 21, the male cutting blade 19 is pressed against the lead frame 9 from the upper surface side and the female cutting blade 21 is pressed from the back surface side to cut the recess 13 to separate the SON from the lead frame 9 (( c)). FIG. 5 is an enlarged sectional view showing the vicinity of the lead 3 and the cutting blade.
As a result, the tip portion 3 a of the lead 3 described above with reference to FIG. 1 is bent upward to form a stepped portion 3 c on the lower surface 3 b of the lead 3, and the sag surface 3 e is the lower surface of the tip surface of the lead 3. The SON formed on the 3b side can be manufactured.

  6A and 6B are diagrams showing another embodiment of the semiconductor device, wherein FIG. 6A is a plan view, FIG. 6B is a side view seen from the A direction, FIG. 6C is a side view seen from the B direction, and FIG. A bottom view, (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). In this embodiment, the first embodiment of the semiconductor device of the present invention is applied to a leadless type SON. The same parts as those in FIG.

  In the SON of this embodiment, a plurality of leads 23 are provided on the side surface of the sealing resin 1. A part of the lead 23 is exposed on the bottom surface of the sealing resin 1. The dimensions and arrangement of the leads 23 are the same as in the embodiment described with reference to FIG. The leading end portion 23 a of the lead 23 is bent upward by, for example, half the thickness of the lead 23 by a half punching method, and a stepped portion 23 c is formed on the lower surface 23 b of the lead 23. The thickness and width dimension of the distal end portion 23a are substantially the same as the base end portion of the lead 23, that is, substantially the same as before the lead 23 is bent by the half-punch method.

  A sag surface 23e, a shear surface 23f, a fracture surface 23g, and a cutting burr 23h are formed on the leading end surface of the lead 23 in this order from the upper surface 23d side to the lower surface 23b side. In the lead 23, a plating film (not shown) is formed on the lower surface 23b, the upper surface 23d, the side surface, and the sag surface 23e including the step portion 23c. The shearing surface 23f may or may not be provided with a plating film. Further, the cutting burr 23h may or may not be formed.

7 is a cross-sectional view showing a lead portion in a state where the embodiment shown in FIG. 6 is mounted on a mounting substrate. FIG. 7A shows a case where a solder fillet is formed in a step portion on the lower surface of the lead, and FIG. The case where the solder fillet is formed from the step part on the lower surface of the lead to the tip part is shown.
When the SON is mounted on the mounting substrate 5 and the lead 23 and the electrode (not shown) of the mounting substrate 5 are soldered, the lower surface 23b including the stepped portion 23c of the lead 23 and the tip portion on the side surface are shown in FIG. In some cases, the solder fillet 7 is formed except for 23a, and in other cases, the solder fillet 7 is formed on the lower surface 23b and the side surface including the stepped portion 23c of the lead 23 including the tip 23a as shown in FIG. .

  As described above, the tip 23a of the lead 23 is bent upward and the step 23c is formed on the lower surface 23b of the lead 23, whereby the plating film forming area at the lead tip can be increased, and the solder at the lead tip can be increased. Adhesion can be improved.

  FIG. 8 is a schematic process sectional view for explaining another embodiment of the manufacturing method, and shows a process of manufacturing the semiconductor device shown in FIG. 7 using the lead frame shown in FIG. In FIG. 8, reference numeral 23 is attached instead of reference numeral 3 of the lead frame shown in FIG. An embodiment of the manufacturing method will be described with reference to FIG.

  In the embodiment of the manufacturing method described with reference to FIG. 4, the semiconductor chip 15 is mounted on the die pad 11 of the lead frame 9 in the same manner as the process described with reference to FIGS. 4 (a) and 4 (b). After the bonding wire 17 and the sealing resin 1 are formed, exterior processing such as removal of the sealing resin burr and solder plating is performed (see (a) and (b)).

  A male-type cutting blade 25 (first cutting blade) having a blade thickness on the sealing resin 1 side with respect to the cutting position corresponding to the recess 13 of the lead 23, and the side opposite to the sealing resin 1 with respect to the cutting position A female cutting blade 27 (second cutting blade) having a blade thickness is used, the male cutting blade 25 is pressed against the lead frame 9 from the back surface side, and the female cutting blade 27 is pressed from the top surface side to form the recess 13. Cut the SON from the lead frame 9 (see (c)). FIG. 9 is an enlarged sectional view showing the vicinity of the lead 23 and the cutting blade.

Thereby, the SON in which the tip 23a of the lead 23 is bent upward and the step 23c is formed on the lower surface 23b of the lead 23 described with reference to FIG. 6 can be manufactured.
Further, as a cutting blade for separating the SON from the lead frame 9, a male cutting blade 25 having a blade thickness on the sealing resin 1 side and a blade thickness on the opposite side of the sealing resin 1 with respect to the cutting position. Since the female cutting blade 27 is used, the blade thicknesses of the male cutting blade 25 and the female cutting blade 27 compared to the male cutting blade 19 used in the embodiment of the manufacturing method described with reference to FIG. Can be thickened. For example, when manufacturing a SON having a lead protrusion length of 0.2 mm, it is necessary to use a male cutting blade 19 having a blade thickness thinner than 0.2 mm as shown in FIG. However, according to this embodiment, since the thickness of the male cutting blade 25 and the female cutting blade 27 can be increased, the life of the cutting blade is extended. Therefore, the manufacturing cost can be reduced.

  10A and 10B are views showing still another embodiment of the semiconductor device, wherein FIG. 10A is a plan view, FIG. 10B is a side view seen from the A direction, FIG. 10C is a side view seen from the B direction, and FIG. Is a bottom view, and (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). In this embodiment, the second embodiment of the semiconductor device of the present invention is applied to a leadless type SON. The same parts as those in FIG.

  In the SON of this embodiment, a plurality of leads 31 are provided on the side surface of the sealing resin 1. A part of the lead 31 is exposed on the bottom surface of the sealing resin 1. The dimensions and arrangement of the lead 31 are the same as those of the embodiment described with reference to FIGS. 1 and 6, for example. The tip 31a of the lead 31 is bent downward by, for example, half the thickness of the lead 31 by a half punching method, and a step portion 31c is formed on the lower surface 31b of the lead 31. The thickness and width dimension of the distal end portion 31a are substantially the same as the proximal end portion of the lead 31, that is, substantially the same as before the lead 31 is bent by the half-punch method.

  A sag surface 31e, a shear surface 31f, a fracture surface 31g, and a cutting burr 31h are formed on the tip surface of the lead 31 in order from the lower surface 31b side to the upper surface 31d side. In the lead 31, a plating film (not shown) is formed on the lower surface 31b, the upper surface 31d, the side surface, and the sag surface 31e including the step portion 31c. The shearing surface 31f may or may not be formed with a plating film. Further, the cutting burr 31h may or may not be formed.

11 is a cross-sectional view showing a lead portion in a state where the embodiment shown in FIG. 10 is mounted on a mounting substrate. FIG. 11A shows a case where a plating film is not formed on the shearing surface of the lead tip surface. Indicates a case where a plating film is formed on the shearing surface of the lead tip surface.
When the SON is mounted on the mounting substrate 5 and the lead 31 and the electrode (not shown) of the mounting substrate 5 are solder-connected, the solder fillet 7 is formed on the lower surface 31b and the side surface including the step portion 31c of the lead 31 (( A) and (B)). Further, as shown in (B), when a plating film is formed on the shearing surface 31f of the tip surface of the lead 31, the solder fillet 7 is also formed on the shearing surface 31f.
Furthermore, since the tip portion 31a of the lead 31 is bent downward, for example, 10 to 100 μm (micrometer) between the lower surface of the sealing resin 1 and the surface of the mounting substrate 5 with the SON mounted on the mounting substrate 5. Meter) spacing is formed.

As described above, the tip 31a of the lead 31 is bent downward and the step portion 31c is formed on the lower surface 31b of the lead 31, thereby increasing the plating film formation area at the lead tip. Solder adhesion can be improved.
Furthermore, in this embodiment, since the sag surface 31e is formed on the lower surface 31b side at the front end surface of the lead 31, the plating film formation area at the front end of the lead can be further increased.
Furthermore, since a space can be formed between the lower surface of the sealing resin 1 and the surface of the mounting substrate 5 in a state where the SON is mounted on the mounting substrate 5, small dust 33 or the like enters under the sealing resin 1. However, it is possible to prevent the soldering from being affected.

  12A and 12B are views showing another embodiment of the lead frame, in which FIG. 12A is a plan view and FIG. 12B is a cross-sectional view taken along the line BB in FIG. FIG. 13 is a schematic process cross-sectional view for explaining still another embodiment of the manufacturing method, and shows a process of manufacturing the semiconductor device shown in FIG. 10 using the lead frame shown in FIG. First, an embodiment of the lead frame will be described with reference to FIG.

The lead frame 35 is formed with a plurality of sets each including a die pad 11 for mounting a semiconductor chip and a plurality of leads 31 provided close to the die pad 11. In the lead 31, a portion corresponding to the leading end of the lead after cutting is formed in a convex shape downward by a half punching method, and a convex portion 37 is formed on the back surface 31b. In (A), illustration of the recessed part corresponding to the convex part 37 is abbreviate | omitted.
In the formation region of the convex portion 37, the area viewed from the upper surface is substantially the same before and after processing, and the volume of the concave portion and the convex portion is substantially the same. In this embodiment, for example, the convex portion 37 is formed by being bent downward by a half dimension of the thickness of the lead 31.

An embodiment of the manufacturing method will be described with reference to FIG.
In the embodiment of the manufacturing method described with reference to FIG. 4, the semiconductor chip 15 is mounted on the die pad 11 of the lead frame 35 in the same manner as the process described with reference to FIGS. 4 (a) and 4 (b). After the bonding wire 17 and the sealing resin 1 are formed, exterior processing such as removal of the sealing resin burr and solder plating is performed (see (a) and (b)).

A male cutting blade 19 having a blade thickness on the sealing resin 1 side with respect to the cutting position corresponding to the convex portion 37 of the lead 31 and a blade thickness on the opposite side of the sealing resin 1 with respect to the cutting position. Using the female cutting blade 21, the male cutting blade 19 is pressed against the lead frame 9 from the upper surface side, and the female cutting blade 21 is pressed from the rear surface side to cut the convex portion 37 to separate the SON from the lead frame 9. (See (c)). FIG. 14 is an enlarged sectional view showing the vicinity of the lead 31 and the cutting blade.
As a result, the tip 31 a of the lead 31 described with reference to FIG. 10 is bent downward to form a stepped portion 31 c on the lower surface 31 b of the lead 31, and the sag surface 31 e is the lower surface on the tip of the lead 31. The SON formed on the 31b side can be manufactured.

  15A and 15B are views showing still another embodiment of the semiconductor device, wherein FIG. 15A is a plan view, FIG. 15B is a side view seen from the A direction, FIG. 15C is a side view seen from the B direction, and FIG. Is a bottom view, and (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). In this embodiment, the second embodiment of the semiconductor device of the present invention is applied to a leadless type SON. The same parts as those in FIG.

  In the SON of this embodiment, a plurality of leads 39 are provided on the side surface of the sealing resin 1. A part of the lead 39 is exposed on the bottom surface of the sealing resin 1. The dimensions and arrangement of the leads 39 are the same as those of the embodiment described with reference to FIG. The leading end 39a of the lead 39 is bent upward by, for example, half the thickness of the lead 39 by a half punching method, and a stepped portion 39c is formed on the lower surface 39b of the lead 39. The thickness and the width dimension of the distal end portion 39a are substantially the same as the base end portion of the lead 39, that is, substantially the same as before the lead 39 is bent by the half punching method.

  A sag surface 39e, a shear surface 39f, a fracture surface 39g, and a cutting burr 39h are formed on the leading end surface of the lead 39 in this order from the upper surface 39d side to the lower surface 39b side. In the lead 39, a plating film (not shown) is formed on the lower surface 39b, the upper surface 39d, the side surface, and the sag surface 39e including the step portion 39c. The shearing surface 39f may or may not be provided with a plating film. Further, the cutting burr 39h may or may not be formed.

16 is a cross-sectional view showing a lead portion in a state where the embodiment shown in FIG. 15 is mounted on a mounting board.
When the SON is mounted on the mounting substrate 5 and the lead 39 and the electrode (not shown) of the mounting substrate 5 are soldered, the solder fillet 7 is formed on the lower surface 39b and the side surface including the stepped portion 39c of the lead 39.
Furthermore, since the tip 39a of the lead 39 is bent downward, a distance of, for example, 10 to 100 μm is provided between the lower surface of the sealing resin 1 and the surface of the mounting substrate 5 in a state where the SON is mounted on the mounting substrate 5. Is formed.

As described above, the tip 39a of the lead 39 is bent downward and the step 39c is formed on the lower surface 39b of the lead 39, so that the plating film formation area at the tip of the lead can be increased. Solder adhesion can be improved.
Furthermore, since a space can be formed between the lower surface of the sealing resin 1 and the surface of the mounting substrate 5 in a state where the SON is mounted on the mounting substrate 5, small dust 33 or the like enters under the sealing resin 1. However, it is possible to prevent the soldering from being affected.

  FIG. 17 is a schematic process cross-sectional view for explaining still another embodiment of the manufacturing method, and shows a process of manufacturing the semiconductor device shown in FIG. 15 using the lead frame shown in FIG. In FIG. 17, a reference numeral 39 is attached instead of the reference numeral 31 of the lead frame shown in FIG. An embodiment of the manufacturing method will be described with reference to FIG.

  In the embodiment of the manufacturing method described with reference to FIG. 4, the semiconductor chip 15 is mounted on the die pad 11 of the lead frame 35 in the same manner as the process described with reference to FIGS. 4 (a) and 4 (b). After the bonding wire 17 and the sealing resin 1 are formed, exterior processing such as removal of the sealing resin burr and solder plating is performed (see (a) and (b)).

  The male cutting blade 25 (first cutting blade) having a blade thickness on the sealing resin 1 side with respect to the cutting position corresponding to the convex portion 37 of the lead 39 and the sealing resin 1 opposite to the cutting position. Using a female cutting blade 27 (second cutting blade) having a blade thickness on the side, the male cutting blade 25 is pressed against the lead frame 35 from the back surface, and the female cutting blade 27 is pressed from the top surface to project 37 is cut to disconnect the SON from the lead frame 35 (see (c)). FIG. 18 is an enlarged sectional view showing the vicinity of the lead 39 and the cutting blade.

Accordingly, the SON described with reference to FIG. 15 in which the tip 39a of the lead 39 is bent downward and the step 39c is formed on the lower surface 39b of the lead 39 can be manufactured.
Further, similarly to the embodiment of the manufacturing method described with reference to FIG. 6, as a cutting blade for separating SON from the lead frame 35, a male cutting blade 25 having a blade thickness on the sealing resin 1 side, Since the female cutting blade 27 having a blade thickness on the side opposite to the sealing resin 1 with respect to the cutting position is used, the cutting blades having the male cutting blade 25 and the female cutting blade 27 are made thicker. The lifetime of the battery can be extended, and the manufacturing cost can be reduced.

  In the above-described embodiments, the present invention is applied to the SON. However, the present invention is not limited to this. For example, the present invention is applied to a leadless type semiconductor device other than the SON, such as QFN, and a gull wing type semiconductor device. be able to. Embodiments in which the present invention is applied to a gull wing type semiconductor device will be described below.

  19A and 19B are diagrams showing still another embodiment of the semiconductor device, wherein FIG. 19A is a plan view, FIG. 19B is a side view, and FIG. 19C is an enlarged view of a portion surrounded by a broken-line circle in FIG. . In this embodiment, the first embodiment of the semiconductor device of the present invention is applied to a gull-wing type semiconductor device.

  A plurality of leads 41 are provided on the side surface of the sealing resin 1 for sealing the semiconductor chip. The lead 41 is provided so as to protrude in the horizontal direction from the side surface of the sealing resin 1, and the tip is bent downward and further bent in the horizontal direction. The tip portion 41a of the lead 41 has the same configuration as the tip portion 3a of the lead 3 of the embodiment described with reference to FIG. 1, and is moved upward by, for example, half the thickness of the lead 41 by a half punching method. The step 41c is provided on the lower surface 41b of the lead 41 by bending, and the tip surface of the lead 41 is provided with a sag surface 41e, a shear surface 41f, a fracture surface 41g, and a cutting burr 41h in order from the lower surface 41b side to the upper surface 41d side. The thickness and width dimension of the distal end portion 41a are substantially the same as the base end portion of the lead 41, that is, substantially the same as before the lead 41 is bent by the half-punch method.

20 is a cross-sectional view showing a lead portion in a state where the embodiment shown in FIG. 19 is mounted on a mounting substrate. FIG. 20A shows a case where a plating film is not formed on the shear surface of the lead tip surface. Indicates a case where a plating film is formed on the shearing surface of the lead tip surface.
When the semiconductor device is mounted on the mounting substrate 5 and the lead 41 and the electrode (not shown) of the mounting substrate 5 are solder-connected, the solder fillet 7 is formed on the lower surface 41 b and the side surface including the stepped portion 41 c of the lead 41 ( (See (A) and (B)). Further, as shown in (B), when a plating film is formed on the shearing surface 41f of the tip surface of the lead 41, the solder fillet 7 is also formed on the shearing surface 41f.

Thus, in the gull wing type semiconductor device, similarly to the SON embodiment, the tip 41a of the lead 41 is bent upward and the step 41c is formed on the lower surface 41b of the lead 41. The plating film formation area at the lead tip can be increased, and the solder adhesion at the lead tip can be improved.
Further, in this embodiment, since the sag surface 41e is formed on the lower surface 41b side at the tip surface of the lead 41, the plating film formation area at the lead tip can be further increased.
Furthermore, since the cutting burr 41h is formed on the upper surface 41d side at the tip surface of the lead 41, variations in the mounting height can be suppressed.

  21A and 21B are views showing still another embodiment of the lead frame, in which FIG. 21A is a plan view and FIG. 21B is a cross-sectional view taken along the line CC in FIG. FIG. 22 is a schematic process cross-sectional view for explaining an embodiment of the manufacturing method, and shows a process of manufacturing the semiconductor device shown in FIG. 19 using the lead frame shown in FIG. First, an example of a lead frame will be described with reference to FIG.

The lead frame 43 includes a die pad 11 for mounting a semiconductor chip, a plurality of leads 41 provided close to the die pad 11, and a tie bar 45 for supporting an end portion of the lead 41 near the die pad 11. A plurality of sets are formed. In the lead 41, a portion corresponding to the tip of the lead after cutting is formed in a convex shape upward by a half punching method, and a concave portion 47 is formed in the back surface 41b. In (A), illustration of the convex part corresponding to the concave part 47 is omitted.
In the region where the recess 47 is formed, the area viewed from above is substantially the same before and after processing, and the volume of the recess and the protrusion is approximately the same. In this embodiment, for example, the concave portion 47 is formed by bending upward by a half dimension of the thickness of the lead 41.

An embodiment of the manufacturing method will be described with reference to FIG.
In the embodiment of the manufacturing method described with reference to FIG. 4, the semiconductor chip 15 is mounted on the die pad 11 of the lead frame 43 in the same manner as the process described with reference to FIGS. 4 (a) and 4 (b). After the bonding wire 17 and the sealing resin 1 are formed, exterior processing such as removal of the sealing resin burr and solder plating is performed (see (a) and (b)).

  A male cutting blade 49 having a blade thickness on the sealing resin 1 side with respect to the cutting position corresponding to the recess 47 of the lead 41, and a female having a blade thickness on the opposite side of the sealing resin 1 with respect to the cutting position. Using the die cutting blade 50, the male cutting blade 49 is pressed against the lead frame 43 from the upper surface side, and the female cutting blade 50 is pressed from the back surface side to cut the recess 47 to separate the semiconductor device from the lead frame 43 ( (See (c)). FIG. 23 is an enlarged sectional view showing the vicinity of the lead 41 and the cutting blade. Although not shown, the cutting blades 49 and 50 are also provided with a blade for cutting the tie bar 45 shown in FIG. 21, and the tie bar 45 is cut simultaneously with the cutting of the lead 41. Here, in the case of a gull-wing type semiconductor device, unlike the case of SON, the cutting position is provided with a sufficient distance from the sealing resin 1, so that the male cutting blade 49 will be described with reference to FIG. What has a blade thickness thicker than the male cutting blade 19 used in the embodiment of the manufacturing method described above can be used.

  Thereafter, by processing the lead 41 into a predetermined gull wing shape, the tip 41a of the lead 41 described with reference to FIG. 19 is bent upward to form a step 41c on the lower surface 41b of the lead 41, and A gull wing type semiconductor device in which the sag surface 41e is formed on the lower surface 41b side at the tip surface of the lead 41 can be manufactured.

  The above-described embodiment described with reference to FIGS. 19 to 23 is a gull-wing type semiconductor device, and the tip 41a of the lead 41 has the tip of the lead 3 of the embodiment described with reference to FIGS. Although the semiconductor device manufacturing method and the lead frame used therefor having the same configuration as the portion 3a are described, the present invention is not limited to this. In the gull-wing type semiconductor device, the configuration of the leading end portion of the lead will be described with reference to the same configuration as the leading end portion 23a of the lead 23 of the embodiment described with reference to FIGS. The same configuration as the tip portion 31a of the lead 31 of the embodiment described above, and the same configuration as the tip portion 39a of the lead 39 of the embodiment described with reference to FIGS. 15 to 18 can also be applied. The same effect can be obtained. The same applies to the semiconductor device manufacturing method and the lead frame.

  As mentioned above, although the Example of this invention was described, a dimension, a shape, arrangement | positioning, etc. are examples, this invention is not limited to this, Various within the range of this invention described in the claim Can be changed.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Example of a semiconductor device, (A) Top view, (B) The side view seen from the A direction, (C) The side view seen from the B direction, (D) is a bottom view, E) is an enlarged view of a portion surrounded by a broken-line circle in (B). It is sectional drawing which shows the lead part of the state mounted in the mounting board | substrate in the Example, (A) is the case where the plating film is not formed in the shearing surface of a lead front end surface, (B) is the shearing surface of a lead front end surface Shows the case where a plating film is formed. It is a figure which shows one Example of a lead frame, (A) Top view, (B) is sectional drawing in the AA position of (A). It is general | schematic process sectional drawing for demonstrating one Example of a manufacturing method. It is sectional drawing which expands and shows the lead vicinity and cutting blade at the time of the lead cutting | disconnection in the Example. It is a figure which shows the other Example of a semiconductor device, (A) Top view, (B) The side view seen from the A direction, (C) The side view seen from the B direction, (D) is a bottom view, (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). It is sectional drawing which shows the lead part of the state mounted in the mounting board | substrate in the same Example, (A) is a front-end | tip from the level | step-difference part of a lead lower surface, when (A) has a solder fillet formed in the level | step-difference part of a lower surface of a lead The case where the solder fillet is formed over the part is shown. It is an outline process sectional view for explaining other examples of a manufacturing method. It is sectional drawing which expands and shows the lead vicinity and cutting blade at the time of the lead cutting | disconnection in the Example. It is a figure which shows the further another Example of a semiconductor device, (A) Top view, (B) The side view seen from the A direction, (C) The side view seen from the B direction, (D) is a bottom view (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). It is sectional drawing which shows the lead part of the state mounted in the mounting board | substrate in the Example, (A) is the case where the plating film is not formed in the shearing surface of a lead front end surface, (B) is the shearing surface of a lead front end surface Shows the case where a plating film is formed. It is a figure which shows the other Example of a lead frame, (A) Top view, (B) is sectional drawing in the BB position of (A). It is a schematic process sectional drawing for demonstrating the further another Example of a manufacturing method. It is sectional drawing which expands and shows the lead vicinity and cutting blade at the time of the lead cutting | disconnection in the Example. It is a figure which shows the further another Example of a semiconductor device, (A) Top view, (B) The side view seen from the A direction, (C) The side view seen from the B direction, (D) is a bottom view (E) is an enlarged view of a portion surrounded by a broken-line circle in (B). It is sectional drawing which shows the lead part of the state mounted in the mounting board | substrate in the Example. It is a schematic process sectional drawing for demonstrating the further another Example of a manufacturing method. It is sectional drawing which expands and shows the lead vicinity and cutting blade at the time of the lead cutting | disconnection in the Example. It is a figure which shows other Example of a semiconductor device, (A) Top view, (B) is a side view, (C) is an enlarged view of the part enclosed with the broken-line circle of (B). It is sectional drawing which shows the lead part of the state mounted in the mounting board | substrate in the Example, (A) is the case where the plating film is not formed in the shearing surface of a lead front end surface, (B) is the shearing surface of a lead front end surface Shows the case where a plating film is formed. It is a figure which shows other Example of a lead frame, (A) Top view, (B) is sectional drawing in CC position of (A). It is an outline process sectional view for explaining other examples of a manufacturing method. It is sectional drawing which expands and shows the lead vicinity and cutting blade at the time of the lead cutting | disconnection in the Example. It is a side view of the outer lead before the cutting | disconnection in a prior art. It is a figure which shows the lead front-end | tip part in another prior art, (A) is a top view before press processing, (B) is a top view after press processing, (C) is a side view after press processing. It is a top view of the lead before cutting in still another prior art. It is a side view of the lead tip part in still another prior art.

Explanation of symbols

1 Sealing resin 3, 23, 31, 39, 41 Lead 3a, 23a, 31a, 39a, 41a Lead tip 3b, 23b, 31b, 39b, 41b Lead lower surface 3c, 23c, 31c, 39c, 41c Lead lower surface Steps 3d, 23d, 31d, 39d, 41d of the upper surface 3d of the lead
3e, 23e, 31e, 39e, 41e Sag surface 3f, 23f, 31f, 39f, 41f Shear surface 3g, 23g, 31g, 39g, 41g Broken surface 3h, 23h, 31h, 39h, 41h Cutting burr 5 Mounting substrate 7 Solder fillet 9 Lead frame 11 Die pad 13 Recess 15 Semiconductor chip 17 Bonding wire 19 Male cutting blade 21 Female cutting blade 25 Male cutting blade 27 Female cutting blade 33 Garbage 35 Lead frame 37 Convex 43 Lead frame 45 Tie bar 47 Concave 49 Male Die cutting blade 50 Female cutting blade

Claims (8)

In a semiconductor device provided with a plurality of leads on the outer edge of a sealing resin and a sealing resin for sealing a semiconductor chip,
2. A semiconductor device according to claim 1, wherein a tip end portion of the lead is bent upward by a half punching method. In a semiconductor device provided with a plurality of leads on the outer edge of a sealing resin and a sealing resin for sealing a semiconductor chip,
2. A semiconductor device according to claim 1, wherein a tip end portion of the lead is bent downward by a half punching method.   3. The semiconductor device according to claim 1, wherein a sag surface is formed on an upper surface side of a tip surface of the lead.   3. The semiconductor device according to claim 1, wherein a sag surface is formed on a lower surface side of the leading end surface of the lead.   The semiconductor device according to claim 1, wherein the semiconductor device is a leadless type. In a lead frame used in a semiconductor device provided with a plurality of leads on the outer edge of a sealing resin and a sealing resin for sealing a semiconductor chip,
A lead frame, wherein a portion corresponding to the tip of the lead after cutting is formed in a convex shape upward or downward by a half punching method. In a manufacturing method of a semiconductor device provided with a plurality of leads on an outer edge portion of a sealing resin and a sealing resin for sealing a semiconductor chip,
Using a lead frame in which a portion corresponding to the tip of the lead after cutting is formed in a convex shape upward or downward by a half-punch method, a semiconductor chip is mounted on the lead frame and subjected to resin sealing treatment and plating treatment. And a step of cutting the protruding portion of the lead frame to separate the semiconductor device from the lead frame.   When cutting the convex portion, a first cutting blade having a blade thickness on the sealing resin side with respect to the cutting position and a second cutting having a blade thickness on the side opposite to the sealing resin with respect to the cutting position 8. The method of manufacturing a semiconductor device according to claim 7, wherein a blade is used to cut the convex portion by pressing the first cutting blade against the lead frame from the back surface side and the second cutting blade from the top surface side. .

Images