JPS6258537B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device chip mounted with an electronic component such as a semiconductor element in a hole or notch formed in a carrier film body, which is held by a wiring lead, and a bridge constructed from the carrier film body. The present invention relates to a carrier film punching and forming device that punches out a wiring lead and a bridge part that supports it from a carrier film that supports a wiring lead extending over a hole or notch, and bends and forms the wiring lead. The purpose of this invention is to shorten the length of the bridge portion that holds the wire leads, thereby improving the mounting density of the wire leads, and to facilitate bonding of the wire leads to the board.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a carrier film. 1 is a carrier film main body (hereinafter abbreviated as film) in which holes 2, 3, and 4 are formed. 4 is a sprocket hole for driving or positioning the film. Reference numeral 5 denotes a wiring lead (hereinafter abbreviated as a lead) disposed on the film 1, the tip of which projects into the hole 2, and a device chip (hereinafter abbreviated as a chip) 6 is bonded to it. This chip 6 is punched out from the film 1 together with the required leads as shown in FIG.
The leads 7 are bonded and mounted to the leads 9 of.

A top view of FIG. 2B is shown in FIG. Bridge 1
If the width T of 1 is large, the packaging density cannot be increased. Recently, in order to improve the packaging density, the pitch of the leads 7 has become finer, for example, 100 to 200 μm, and the bridge 11 is constructed to hold the finer leads. Therefore, in order to improve the packaging density, the bridge width T
It is necessary to reduce the size and simultaneously perform punching and bending.

FIG. 4 is an external perspective view of an embodiment of the device of the present invention;
FIG. 5 is a sectional view taken along line GH in FIG. 4. In these figures, 20 is a die holder;
Four guide posts 21 and 22 are planted on this, and a die 23 is fixed with bolts 24. 2
5 is a positioning pin fixed to the die 23;
The film 1 is positioned by fitting into the sprocket hole 4 of the film 1 shown in the figure. 26 is an upper punch holder, which is guided by the guide post 21 in the vertical direction, that is, the arrow J.
The upper punch 27 is guided in the direction of the bolt 2.
8. A film presser 29 is built into the upper punch 27 so as to be slidable in the vertical direction, and is always urged downward by a spring 30, with a lower end surface 31 protruding from the lower end surface 32 of the upper punch 27. Reference numeral 33 denotes a shaft supported by a bush 34 press-fitted into the upper punch holder 26 so as to be slidable in the vertical direction, and is always urged downward by a spring 35 and is in the state shown in FIG. 5. A plate 36 receives the spring 35, and is separated from the member 36-1 and fixed to the upper punch holder 26 with screws 37. A stripper 38 is fixed to the shaft 33 by a bolt 39-1, supports the film 1 in a groove 39 so as to be slidable in the longitudinal direction thereof, and also serves as a guide member for the film 1. 40 is a lower punch holder supported by the guide post 22 so as to be slidable in the vertical direction, that is, in the direction of arrow K, and the lower punch 41 is movable in the direction of arrow L on an upper table 43 fixed with bolts 42 by means of a slide bearing 44. Supporting lower table 4
9 is fixed. 41-1 is a hole passing through the lower punch 41, and 46 is a nipple connecting one end of the tube 47. The other end of the tube 47 is connected to a negative pressure source (not shown), and the upper surface 48 of the lower punch 41
of air is sucked in.

Upper punch holder 26 and lower punch holder 40
is driven in the vertical direction by a known means such as an air cylinder or a hydraulic cylinder (not shown), and the upper table 43 on which the lower punch 41 is placed is similarly driven in the direction of arrow L. 49-1 is upper table 4
3 to position the upper table 43 at a position where the lower punch 41 can be inserted into the hole 50 of the die 23. Also, 51 is the lower punch holder 4
When the lower punch holder 40 is urged upward by a means (not shown), the pin set at 0 comes into contact with the lower surface 20-1 of the die holder 20, and the lower punch 4
The top surface 48 of the die 23 is aligned with the top surface 52 of the die 23, and the die 23 is placed on standby in the state shown in FIG. The film 1 is driven longitudinally at a required pitch by a known sprocket wheel (not shown) or the like.

Next, the operation of the above-mentioned device will be explained. Figure 6 is an enlarged view of the main parts in standby state, Figure 7 is M of Figure 6.
-N line sectional view, and FIG. 8 is a bottom perspective view of the upper punch 27 and film presser 29 in FIG. 6. When the upper punch holder 26 is urged downward by means not shown, the stripper 38 is first pressed as shown in FIG.
presses the film 1 against the upper surface 52 of the die 23.
At this time, the positioning pin 25 fits into the hole 4 of the film 1 to accurately position the film 1.

Next, the lower surface 31 of the film presser 29 holds the film 1.
The bridge 11 shown in FIG. 1 is pressed against the upper surface 48 of the lower punch 41. If the downward biasing force of the film presser 29 by the spring 30 is F ₁ and the upward biasing force of the lower punch 41 by means not shown is F ₂ , then if F ₁ <F ₂ , then the film presser 29 is
9, the upper punch 27 descends while stopping, and the 10th
As shown in the figure, the cutting edge 53 of the upper punch 27 acts with the cutting edge 54 of the die 23 to punch out the film 1, and as the upper punch descends, the bending edge 55 of the upper punch acts with the stepped portion 56 of the lower punch 41. Then, the lead 7 is bent and formed. Therefore, lead 7 is film 1
Since the lead 7 is bent after being separated from the lead 7, almost no tension is applied to the lead 7 during bending, and even if the lead is deeply bent or formed, it will not be cut even if the lead is thin. Furthermore, since the bridge 11 is strongly held between the film presser 29 and the lower punch 41, even if some tension is applied to the lead 7 during punching and bending the film 1, the bonding portion 12 between the chip 6 and the lead 5 is Since no force is applied to the bonding part, the bonding part will not come off.

FIG. 11 shows a cross section taken along the line P-Q in FIG. 10. The upper punch 27 has a recess 6 as shown in FIG.
0 is configured, and a cutting edge 6 is placed inside the recess.
1 is configured. Therefore, when the upper punch 27 descends from the state shown in FIG.
The bridge 11 is cut by the cutting edge 62 formed on the stepped portion of the lower punch 41, resulting in the state shown in FIG. At this time, the gap R between the upper punch 27 and the die 23 is made sufficiently larger than the thickness of the bridge 11 to prevent the bridge from being cut in this gap. The reason for this is that if the bridge is also cut between the upper punch 27 and the die 23, the cut bridge must also be recovered. Thus, as shown in FIG. 13, a leaded chip 66 is punched out from the film 1 and completed by bending the lead.

In addition, as shown in _FIG .
By making it smaller than F ₃ and pushing down the lower punch 41 with the upper punch 27 via the film piece 67, the impact when the film piece 67 is sandwiched between the upper punch 27 and the lower punch 41 can be alleviated. When the leads 5 of the film piece 67 are crushed and widened, and the pitch of the leads 5 is fine, it is possible to prevent adjacent leads from being short-circuited. At this time, it is more effective to attach the lower punch 41 to the upper table 43 via an elastic body such as a spring or rubber.

Furthermore, even if the upper punch 27 and lower punch 41 descend to the state shown in FIG. 12, the bridge 11 shown in FIG. There will be no disconnection.

Next, from the state shown in FIG. 12, the leaded chip 66 is adsorbed to the upper surface 48 of the lower punch 41 by passing negative pressure through the hole 41-1, and the lower punch 41 is lowered by means not shown, and further, as shown in FIG. Then, the upper table 43 is moved to the left of arrow L by means not shown to a position S shown by a two-dot chain line. At this position, suction is automatically stopped by a means not shown, so that the tip 66 with the lead can be recovered by climbing onto the upper surface 48 of the lower punch. At this time, lower punch 4
1 is located outside the side surface 68 of the die holder 20, so recovery is very easy.

Next, other embodiments of the present invention will be shown. When punching and molding a carrier film 1 having leads 7 arranged in four directions from a chip 6 as shown in FIG. 14, each part may be configured as shown in FIG. 15. In FIG. 15, a is the film presser 29, b
is a bottom perspective view of the upper punch 27, c is the die 23, d
2 is a top perspective view of the lower punch 41. FIG. In addition, the first
In FIG. 4 and FIG. 15, the same parts as in the previous embodiment are given the same reference numerals. Furthermore, the concave portion 63 in FIG.
This is an escape to avoid cutting 1. In this way, similarly to the film 1 of FIG. 1, the leaded tip 6 is transferred from the film 1 of FIG. 14 as shown in FIG.
6 can be punched and bent.

In the above embodiments, the lead 7 is very thin and is easily deformed by external force, and the corresponding device configuration is described. However, if the lead 7 is relatively thick and rigid, each film piece 67 There is no need to punch out, just punch out at the lead 7 part.

As described above, the present invention provides an apparatus for punching out leads and bridges from a carrier film having a bridge portion that supports the leads extending into a hole or notch, in which wiring leads are punched out using an upper punch and a die, and the upper punch and the die are used to punch out wiring leads. The lower punch punches out the bridge part and bends the lead. Since the bridge part can be punched out very close to the chip or lead, the protrusion of the bridge from the leaded chip can be minimized. As a result, the packaging density of leaded chips can be improved.
Furthermore, punching and bending can be performed at the same time, which makes the leads more susceptible to deformation due to tension or contact with the machine during transfer from the punching process to the bending process, compared to when these processes are performed in separate processes. There is no risk of it happening.

In addition, in the case of a film with four-way leads as shown in FIG. 16, if there is a protruding bridge 75 as shown in FIG. 17, it will be difficult to It is accompanied by difficulties as described in . That is, FIG. 18 is a bottom perspective view of a bonding tool used when four leads 7 are simultaneously subjected to constant heating type solder reflow bonding. In the figure, 80 is a lead presser made of a thin plate, 81 is a lead presser formed by bending the lower part of the lead presser, and 82 is a notch to avoid interference with the protruding portion 75 of the bridge mentioned above. Reference numeral 83 denotes a bonding tool which is constantly heated by a heater (not shown) and is supported to be movable up and down relative to the lead presser 80. Reference numeral 84 is a notch for avoiding the protruding portion 75 of the bridge. When performing bonding,
First, the lead 7 is held down by the lead pressing part 81, and then the bonding tool 83 is lowered and the lower surface 85 of the tool is pressed down.
is pressed onto the lead pressing section 81, and heat from the tool 83 is applied to the lead 7 via the lead pressing section 81. When bonding is completed, the lead pressing part 8
At step 1, only the tool 83 is raised while holding down the lead 7 to cool the lead 7, and after the solder has solidified, the lead presser 80 is raised to complete the work.

However, if the bonding tool 83 has notches 82 and 84 as shown in FIG. 18, the temperature near the notches is less likely to rise compared to the center, so that the lead 86 at the end of the lead 7 is not bonded. This results in a significant decrease in bonding reliability. Furthermore, since the lead presser 80 is made of a thin plate, if there is a notch, the rigidity will be significantly reduced and it will be easily deformed.Also, the lead presser 80 and the bonding tool 83 must both be provided with a notch, which makes processing difficult. It has the disadvantage of being complicated.

In the present invention, by eliminating the protruding portion 75 of the bridge, the above-mentioned notches 82 and 84 can be eliminated, thereby increasing the reliability of bonding and making it possible to bond four locations at the same time using an easy-to-process tool. Effects can be obtained.

Further, when bonding the leads 7 one by one, a pulse energization method is generally used. FIG. 19 shows a bottom perspective view of the pulse energization type bonding tool. In FIG. 19, the lower surface 91 of the tool 90 is the contact surface against the lead 7.
A pulsed current is passed through this tool to generate Joule heat on the lower side 92 to perform bonding. However, in general, the temperature distribution on the lower side 92 is higher at the center 93 and lower at the ends 94. Therefore, since the effective length of the lower surface 91 is considerably shorter than the overall length X, X must be made considerably longer than the width Y of the lead 7 shown in FIG. However, since the overall length X is limited by the protruding portion 75 of the bridge, the lead 86 at the end of the lead 7 is difficult to be heated, as described above, and the reliability of bonding is significantly reduced. Also, the 17th
As shown in the figure, the lead widths Y and Z are different,
Furthermore, if the dimensions differ depending on the product type, a large number of tools corresponding to those dimensions must be prepared and the tools must be replaced each time the work is carried out, which significantly impairs economic efficiency and work efficiency.

In the present invention, since there is no protruding portion 75 of the bridge, a tool with a large width X can be used.
Furthermore, by making the width X long enough to accommodate all types of products, only one tool is required, making it possible to bond with high reliability and excellent efficiency in terms of economy and workability.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an example of a carrier film, FIG. 2 is an explanatory diagram of the process of punching and bending wiring leads and bridge parts from the carrier film, FIG. 3 is a top view of FIG. 2B, and FIG. 12 show one embodiment of the present invention, FIG. 4 is a schematic external perspective view, FIG. 5 is a sectional view taken along line GH in FIG. 4, and FIG. 6 is a main part of FIG. 5. An enlarged view, FIG. 7 is a sectional view taken along line M-N in FIG. 6, FIG. 8 is a perspective view of main parts, FIGS. 9 and 10.
12 is an explanatory diagram of the operation, FIG. 11 is a sectional view taken along the line P-Q in FIG. 10, FIG. 13 is a perspective view of a punched film and a leaded chip, and FIG. A perspective view of a carrier film of another embodiment,
FIG. 15 is a diagram showing the shape of each part of the device of the present invention for processing the film shown in FIG. 14, and FIG. 16 is a diagram showing a film and a lead attached to it that have been punched and formed by the device constructed in the shape shown in FIG. 15. FIG. 17 is a top view of a leaded chip punched with a conventional device, and FIGS. 18 and 19 are perspective views of a conventional bonding tool. 1...carrier film, 2, 3, 4...hole,
5, 7...Wiring lead, 6...Device chip,
11... Bridge, 23... Die, 27... Upper punch, 29... Film presser, 41... Lower punch, 56... Step portion, 61, 62... Cutting edge, 66
...Tip with a lead.

Claims (1)

[Scope of Claims] 1. A device chip held by a wiring lead in a hole or notch provided in a carrier film body, and a bridge that supports the wiring lead built from the carrier film body and extending into the hole or notch. An apparatus for punching out wiring leads and bridge parts from a carrier film having an upper punch and bending the wiring leads in the holes or notches, the apparatus comprising: an upper punch;
a die that acts with the upper punch to punch out the wiring leads of the carrier film; and a die that acts with the upper punch to punch out the bridge portion of the carrier film and punch out the wiring leads extending into the holes or notches of the film; 1. A carrier film punching and forming device comprising a lower punch having a stepped portion for bending and forming the carrier film by acting with the upper punch. 2. In order to prevent the bridge part punched by the stepped portions of the upper punch and the lower punch from being pressed between the lower surface of the upper punch and the lower surface of the stepped portion of the lower punch, the lower surface of the upper punch or the lower surface of the stepped portion of the lower punch is A carrier film punching and forming device according to claim 1, characterized in that a recess is provided in the carrier film. 3. The carrier film punching and forming apparatus according to claim 1, wherein the clearance between the die and the upper punch that abuts the bridge portion is set to a value that does not cause the bridge portion to be cut.