JPH04148750A - Intermittent transfer device for rectangular lead frame for manufacturing semiconductor parts - Google Patents

Abstract

PURPOSE:To transfer two frames simultaneously and intermittently by making a feed head provided in an intermittent transfer mechanism capable of moving UP and down, employing two feed pins for fitting into feed hales in a lead frame to make the feed head capable of reciprocating, and making the pin distance greater than the overall length of the lead frame. CONSTITUTION:In front of a feed mechanism for transferring a lead frame A in the longitudinal direction of a guide rail 1 is provided an intermittent transfer mechanism 10 provided with a feed head 16 capable of moving up and down. Two lead pins 27, 28 for engaging with feed holes in the lead frame A are provided on the feed head 10 at positions apart from each other by a distance greater than the overall length of the lead frame A. The lead frame A is intermittently transferred by inserting the feed pin 27 into the feed hole in the lead frame to advance the frame by the distance of one pitch of a chip attachment portion, and repeating up and down movement. A succeeding lead frame A is similarly transferred. Because the feed pin 28 is inserted in the first lead frame A, intermittent transfer is made at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for intermittently transporting a strip-shaped lead frame used in the manufacture of semiconductor components such as transistors.

[Conventional technology]

Generally, when manufacturing semiconductor components such as transistors using a rectangular lead frame, the rectangular lead frame is intermittently transferred at a pitch in which a semiconductor chip is attached to the lead frame. It is well known that various processing steps are performed, such as die bonding of a semiconductor chip to a lead frame or wire bonding between a semiconductor chip and lead terminals.

In this case, for intermittent transportation of the strip-shaped lead frame, a feed pin is inserted into and engaged with a feed hole bored at a pitch of the semiconductor chip mounting section along the longitudinal direction of the lead frame, By repeating the process of moving the lead frame forward by one pitch using this feed pin, then retracting the feed pin to its original position with the feed pin removed from the feed hole, and then inserting and engaging it into the next feed hole. For attaching semiconductor chips to the lead frame, a method is adopted in which the lead frame is intermittently transferred one pitch at a time.

In this case, conventionally, when performing at least two of the various processing steps at the same time, a plurality of the intermittent transfer mechanisms are arranged along the transfer line of the lead frame. The lead frame in the first processing step and the lead frame in the second processing step of the at least two processing steps are configured to be intermittently transferred by separate intermittent transfer mechanisms. There is.

[Problem to be solved by the invention]

In other words, when performing multiple processing steps at the same time, multiple intermittent transfer mechanisms are used along the lead frame transfer line.
The lead frame is transferred to the first one of the plurality of intermittent transfer mechanisms.
Since a feed mechanism is required for feeding the intermittent transfer mechanism, there is a problem in that the overall size of the transfer device becomes significantly large.

Furthermore, either or both of the overall length of the strip-shaped lead frame and the pitch of the semiconductor chip mounting portion of the lead frame vary depending on the semiconductor component to be manufactured. When handling lead frames with different dimensions or pitch dimensions, the distance between the first intermittent transfer mechanism and the second intermittent transfer mechanism, and the first
Since the distance between the intermittent transfer mechanism and the feeding mechanism must be adjusted accordingly each time one or both of the overall length and pitch dimensions differ, the overall transfer device There was a problem in that the structure became extremely complicated and the adjustment required a great deal of effort.

The technical object of the present invention is to provide a transfer device that solves these problems.

[Means to solve the problem]

In order to achieve this technical problem, the present invention provides a transfer guide rail configured to guide a strip-shaped lead frame along its longitudinal direction, and a lead frame supplied to the upper surface of the transfer guide rail. It consists of a feeding mechanism that moves forward along the longitudinal direction, and an intermittent feeding mechanism that is disposed in front of the feeding mechanism, and the intermittent feeding mechanism includes a feeding head that is moved up and down by a vertical movement means. and at least two feed pins are provided on the feed head, the feed pins being removably fitted into and engaged with feed holes in the lead frame. The intermittent transfer mechanism is provided with reciprocating means for reciprocating the feed head along the longitudinal direction of the transfer guide rail.

[Action/effect of the invention]

In this configuration, when the lead frame is supplied to the upper surface of the transfer guide rail, the lead frame is transferred in the direction of the intermittent transfer mechanism by the feeding mechanism. Then,
By moving the feed head in the intermittent transfer mechanism upwardly, using its reciprocating means to return to the direction of the feeding mechanism, and then moving downwardly using the vertically moving means, at least two feed pins in the feed head are moved. Of these, the first feed pin on the near side in the transfer direction fits into and engages with the feed hole in the lead frame, so in this state, the feed head is moved forward to the original position by its reciprocating means. By doing so, the lead frame can be supplied to the location of the first feed pin.

Next, the feed head in the intermittent transfer mechanism is moved forward in the transfer direction by one pitch of the semiconductor chip mounting section on the lead frame, then moved upward, and then moved backward to the original position and then moved downward, and this is repeated. , while the lead frame is intermittently transferred at one pitch in the semiconductor chip mounting section, the next lead frame is supplied to the upper surface of the transfer guide rail, and then this next lead frame is transferred to the feeding mechanism. and transfer it in the direction of the intermittent transfer mechanism.

Then, the terminal end of the first lead frame is connected to the first lead frame.
When the feed head of the intermittent transfer mechanism is moved up to the feed mechanism, the feed head returns to the feed mechanism and moves backward, and then is moved down by the vertical movement means, thereby moving the first feed pin. is fitted into and engaged with the feed hole in the next lead frame, and at the same time, the second feed pin (of the two feed pins on the front side with respect to the transfer direction) in the feed head is inserted into the first feed pin. Then, by repeating the above operation, the semiconductor chips are mounted on the lead frame intermittently at one pitch of the part. After being transferred, various processing steps are performed at the first feed pin location and the second feed pin location.

As described above, the present invention is for simultaneously transferring at least two lead frames intermittently by -pitch using at least two feed pins provided on the feed head in the intermittent transfer mechanism of the -stand. As there is no need to provide multiple intermittent transfer mechanisms along the transfer guide rail, the device can be significantly downsized.
Moreover, if the lead frame to be handled is changed, the stroke of the reciprocating motion in the intermittent transfer mechanism will be changed.
The mounting of the semiconductor chip on the lead frame only needs to be increased or decreased according to one pitch of the part or the entire length of the lead frame, which simplifies the overall structure of the device and greatly reduces the effort required for adjustment. .

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Below, drawings will be described in which an embodiment of the present invention is applied to a die-bonding process in which a semiconductor chip is bonded to a lead frame using a conductive paste.

In the figure, the symbol A indicates a lead frame formed into a rectangular shape with an appropriate length L from a thin metal plate made of a magnetic material such as an iron plate.
are formed at a constant pitch P along the longitudinal direction of the lead frame A, and one side edge in the longitudinal direction is formed with feed holes or the semiconductor mounting holes are formed at intervals of the same pitch P as part a. It is set up.

Reference numeral 1 indicates a transfer guide rail for guiding the strip-shaped glue frame A along its longitudinal direction, and the transfer guide rail 1 is made of a non-magnetic material such as stainless steel or aluminum. A guide wall surface 1a extending along the longitudinal direction of the transfer guide rail 1 is formed on one side edge in the direction, and permanent magnets 2 are embedded at appropriate intervals along the longitudinal direction. The lead frame A placed on the upper surface of the transfer guide rail 1 is magnetically attached to the guide wall surface 1a, and in this state, the lead frame A is transferred in its longitudinal direction.

The structure is such that the strip-shaped lead frames A stored in the magazine rack 3 are fed one by one onto the upper surface of one end of the transfer guide rail 1.

Reference numeral 4 indicates a feeding mechanism disposed at one end of the transfer guide rail 1, and the feeding mechanism 4 includes a guide member 5 extending along the longitudinal direction of the transfer guide rail 1.
A feed table 6 is supported in a reciprocating manner and a feed pawl 7 is attached to the feed table 6 so that its upper end protrudes above the upper surface of the transfer guide rail 1.

A screw shaft 8 supported parallel to the kite member 5 is screwed onto the feed base 6, and the screw shaft 8 is rotated in forward and reverse directions by a feeding step motor 9.
The lead is supplied to the upper surface of the transfer guide rail 1 by moving forward by an appropriate feed stroke S along the longitudinal direction of the transfer guide rail 1, and then reciprocatingly moving back and returning to the original position. The frame A is configured to be fed by a distance of the appropriate stroke S toward the intermittent transfer mechanism 10, which will be described later.

This intermittent transfer mechanism 10 includes a machine frame 11 and a carriage 13 provided on the upper surface of the machine frame 11 so as to be able to reciprocate along the longitudinal direction of the transfer guide rail 1 via a guide member 12. A screw shaft I4, which is rotatably supported on the machine frame 11, is screwed onto this reciprocating table 13.
4 is rotated forward and backward by an intermittent feed step motor 15, the reciprocating carriage 13 is configured to reciprocate along the longitudinal direction of the transfer guide rail l.

A feed head 16 is attached to the front surface of the reciprocating table 13 in the intermittent transfer mechanism 10 so as to be movable up and down, and the feed head 16 is urged downward by a spring 17. While the roller 18 is provided in the
An auxiliary head 20 is attached to a vertical guide member 19 erected from the upper surface of the machine frame 11 so as to be movable up and down, and this auxiliary head 20 is urged downward by a spring 21. The rollers 22 provided on the rear surface of the upper end of the auxiliary head 20 are brought into contact with the upper surface of the end cam 24 attached to the output shaft of the vertical movement step motor 23, and the support member 25 is horizontally attached to the auxiliary head 20. By attaching the rollers 18 of the feed head 16 to the upper surface of the support member 25 so as to extend, the feed head 16 can be moved up and down by the forward and reverse rotation of the step motor 23 for vertical movement. Configure.

Then, the feed head 16 in the intermittent transfer mechanism 10
In this case, a bracket 26 extending in the longitudinal direction of the transfer guide rail l is fixed, and a feed guide rail in the lead frame A is attached to the front end of the bracket 26 in the transfer direction of the lead frame A. A first feed pin 27 that is removably fitted into and engaged with the feed hole in the lead frame A is also attached to the front end of the lead frame A in the forward direction with respect to the transport direction. In providing the second feeding pins 28 for each, this first
The distance W between the feed pin 27 and the second feed pin 28 is set to be longer than the overall length of the lead frame A by an appropriate amount.

Note that the transfer guide rail l includes the intermittent transfer mechanism l.
A belt conveyor 29 for the lead frame A is provided at a location in front of O.

In this configuration, when the first lead frame A is supplied to the upper surface of one end of the transfer guide rail l as shown in FIG.
By moving the feeding table 6 forward by a feed stroke S in the direction of the intermittent transfer mechanism IO, the lead frame A is moved in the direction of the intermittent transfer mechanism IO as shown in FIG. While feeding to a position where the first feed hole at the tip of A corresponds to the feeding position (B), the feed table 6 with the feed pawl 7 in the feed mechanism 4 retreats to its original position.

Next, the feed head 16 in the intermittent transfer mechanism 10
However, as shown in FIG. 8, the feed head 16 returns from the first processing position (C) at the first feed pin 27 to the feed position (B) by a distance X and then moves downward. By doing so, the feed head 16
The first feed pin 27 is fitted into and engaged with the first feed hole in the lead frame A, as shown in FIG.

Then, the feed head 16 moves forward by the return distance X in the lowered state, thereby moving the lead frame A so that the first feed hole in the lead frame At this first processing position (C), each semiconductor chip is attached to the lead frame A, and the first semiconductor chip is attached to the part a. While applying conductive paste to a, the transfer guide rail 1
A second lead frame A is supplied to the upper surface of one end of the lead frame A.

In this first semiconductor chip mounting, when the application of the conductive paste to part a is completed, the above-mentioned feeding head 1
6 moves forward by one pitch P in the lowered state, rises, then moves backward by one pitch P and descends. By repeating this, the lead frame A is moved to -pitch as shown in Fig. 1θ. In order to attach each semiconductor chip, conductive paste is sequentially applied to each part a at the first processing position (C).

In this way, the first lead frame A is intermittently transferred at intervals of section a, and while the first lead frame A passes through the first processing position (C), the semiconductor chips are attached to the second lead frame A. The second lead frame A is fed by the feeding mechanism 4 so that the first feed hole in the second lead frame A is at the feeding position (B).

Next, the feed head 16 in the intermittent transfer mechanism 10
, moves upward, moves backward by the return distance X from the first processing position (C) toward the feed position (B), and then moves downward, so that the feed The first feed pin 27 in the head 16 is
At the same time as the second lead frame A is fitted into and engaged with the first feed hole, the second feed pin 28 of the feed head 16 is fitted into and engaged with the first feed hole in the first lead frame A. After that, the feed head 16 moves forward by the return distance X, thereby moving the second lead frame A through the first feed hole in the lead frame A to the first processing position (C). At this first processing position (C), each semiconductor chip in the second lead frame A is attached to part a, and the first semiconductor chip is attached to part a. While applying a conductive paste to the lead frame A, the first lead frame A is transferred so that the first perforation hole in the lead frame A is at a first position, and the first lead frame A is transferred to the second processing position. At the position (D), each semiconductor chip is attached to the first lead frame A by die bonding the semiconductor chip to the part a.

Then, by repeating the above operation, each semiconductor chip is mounted on the strip-shaped lead frame A by sequentially applying conductive paste to the portion a at the first processing position (C). The second processing position (D
), the semiconductor chips are sequentially die-bonded, and the lead frame A on which the semiconductor chips have been die-bonded is sent out by a belt conveyor 29.

In the above configuration, the return distance X of the feed head 16 in the intermittent transfer mechanism 10, that is, the feed position CB
) to the first machining position (C), the feed stroke in the feed mechanism 4 is S, and the distance
from the retracted position of the feed claw 7 to the first processing position (C
) is the distance to point Y, while lead frame A
Let Ll be the length from the rear end to the first feed hole a in When the semiconductor chip mounting is replaced with lead frame A' in which the pitch of part a' is P', the feeding stroke in the feeding mechanism 4 is
As shown in FIG. 13, from the above S, S' = Y-(
By adjusting the increase or decrease to change it to X+L'),
With the return distance X of the feed head 16 being the same,
In other words, the lead frame A at the feeding position (B) without changing the return distance
The first feed pin 27 of the intermittent transfer mechanism can be fitted into and engaged with the feed hole b' at '.

Furthermore, the feed stroke in the feed mechanism 4 is
When S is configured to a constant value, in other words, when the feed stroke in the feed mechanism 4 is configured to be unchangeable, the lead frame to be handled has a total length of L and a -pitch as shown in FIG. From the lead frame A of P, as shown in FIG.
Then, when the lead frame A' is replaced with a lead frame A' having a - pitch or P', the feeding position by the feeding mechanism 4 will shift from (B) to (B'), but in this case, the above-mentioned intermittent Feed head 16 in transfer mechanism IO
By increasing or decreasing the return distance X' of the lead frame A', the intermittent transfer mechanism IO
The first sending pin 27 can be fitted and engaged.

In addition, the lead frames to be handled are, as mentioned above, from lead frame A with a -pitch of P to one pitch of P.
', the intermittent feed dimension in the intermittent transfer mechanism IO is changed to the -pitch P.
Of course, it is possible to increase or decrease the pitch by changing it from P' to one pitch P'.

In this case, the feed table 6 with the feed pawl 7 in the feed mechanism 4 is operated by the feed step motor 9, and the feed head 16 in the intermittent transfer mechanism IO is operated by the feed step motor 9.
is configured to reciprocate by the intermittent feed step motor 15, so that the reciprocating stroke of the feed table 6 with the feed pawl 7 in the feed mechanism 4 and the reciprocating movement of the feed head 16 in the intermittent transfer mechanism IO are controlled. Since the stroke can be changed arbitrarily by controlling the pulse signals input to each of the step motors 9 and 15, the feed stroke in the feed mechanism 4 can be changed from S to S' as described above. or increase/decrease adjustment by changing the return distance in the intermittent transfer mechanism 10 from X to X', and increase/decrease adjustment by changing the intermittent feed dimension in the intermittent transfer mechanism IO from P to P'. , can be done extremely easily and with high precision.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall longitudinal sectional front view, FIG. 2 is an overall plan view, FIG. 3 is an enlarged cross-sectional view taken along the line II of FIG. 2, and FIG. 2 is an enlarged sectional view taken along the line ■-■, FIG. 5 is an enlarged sectional view taken along v-v of FIG. 2, FIGS. 6 and 7,
Figures 8, 9, 10 and 11 are enlarged plan views showing the operating state, Figures 12 and 13 are enlarged plane views when the lead frame to be handled is changed, and Figures 14 and 15. The figure is an enlarged plan view showing another embodiment. A, A'...Lead frame, a, a'...
- Semiconductor chip mounting on the lead frame is shown in section b. b'...Feed hole in lead frame, 1...
・Transfer guide rail, 3... Lead frame magazine rack, 4... Feeding mechanism, 6... Feeding stand, 7... Feeding claw, 8... Screw shaft, 9... ...Step motor for feeding, 10...Intermittent transfer mechanism,
11... Machine frame, 13... Carriage carriage, 14
... Screw shaft, 15 ... Step motor for intermittent feed, 16 ... Feeding head)', 18 ... Roller, 2
0... Auxiliary head, 22... Roll, 23...
・Vertical movement step motor, 24... End cam, 2
5... Support member, 26... Feeding head, 27.
28...Feeding pin. Patent applicant ROHM Co., Ltd.

Claims (1)

[Claims] (1) A transfer guide rail configured to guide a strip-shaped lead frame along its longitudinal direction, and a lead frame supplied to the top surface of the transfer guide rail to be moved forward along the longitudinal direction of the transfer guide rail. It consists of a feeding mechanism for transferring, and an intermittent feeding mechanism disposed at a position in front of the feeding mechanism, and the intermittent feeding mechanism is provided with a feeding head that is moved up and down by a vertical movement means, and the feeding head is provided with a feeding head that is moved up and down by a vertical movement means. At least two feed pins that are removably fitted into and engaged with the feed holes in the lead frame,
The transfer guide rails are provided at intervals longer than the entire length of the lead frame along the longitudinal direction of the transfer guide rail, and the intermittent transfer mechanism is configured to reciprocate the feed head along the longitudinal direction of the transfer guide rail. An intermittent transfer device for a strip-shaped lead frame for semiconductor component manufacturing, characterized in that it is provided with a reciprocating means.