JP2800950B2 - Intermittent transfer device for strip-shaped lead frames for manufacturing semiconductor components - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for intermittently transferring a strip-shaped lead frame used for manufacturing a semiconductor component such as a transistor.

[Conventional technology]

Generally, when manufacturing a semiconductor component such as a transistor using a strip-shaped lead frame, the semiconductor chip is intermittently transferred at the pitch of the semiconductor chip mounting portion in the lead frame. It is well known that various processing steps such as die bonding of a chip to a lead frame or wire bonding between a semiconductor chip and a lead terminal are performed.

In this case, for the intermittent transfer of the strip-shaped lead frame, a feed hole formed at the pitch of the semiconductor chip mounting portion along the longitudinal direction of the lead frame,
The feed pin is inserted and engaged, the lead pin is used to move the lead frame forward by one pitch, and then the feed pin is pulled out of the feed hole and retracted to the original position. A method of intermittently transferring the lead frame by one pitch of the semiconductor chip mounting portion by repeating the joining is adopted.

In this case, conventionally, when performing at least two of the various processing steps simultaneously, by arranging a plurality of the intermittent transfer mechanisms along the transfer row 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. I have.

[Problems to be solved by the invention]

That is, when performing a plurality of processing steps simultaneously, the plurality of intermittent transfer mechanisms along the transfer row of the lead frame and the first intermittent transfer mechanism among the plurality of intermittent transfer mechanisms are used. Since a feeding mechanism for feeding is required, there is a problem that the entire transfer device is significantly increased in size.

However, one or both of the overall length of the strip-shaped lead frame and the pitch dimension of the semiconductor chip mounting portion in the lead frame are different depending on the semiconductor component to be manufactured. And when handling a lead frame having one or both of different pitch dimensions, the distance between the first intermittent transfer mechanism and the second intermittent transfer mechanism, and the first intermittent transfer mechanism and the feeding Since the distance to the mechanism must be adjusted accordingly each time one or both of the full length dimension and the pitch dimension are different, the overall structure of the transfer device is significantly reduced. There is a problem that the method is complicated and that the adjustment requires a great deal of trouble.

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

[Means for solving the problem]

In order to achieve this technical object, the present invention relates to a transfer guide rail configured to guide a strip-shaped lead frame A having a length in which feed holes b are formed at intervals of an appropriate pitch P along the longitudinal direction thereof. 1 and the lead frame A supplied to the upper surface of the transfer guide rail 1 is transferred to a position where the first feed hole at the tip of each of the feed holes b coincides with a predetermined feed position B along the transfer guide rail. And the intermittent transfer mechanism 10 disposed at a position forward of the feed mechanism 4 in the transfer direction. The intermittent transfer mechanism 10 is provided with a feed head 16 vertically moved by vertical movement means. Is provided on the feed head 16,
At least two feed pins 27, 2 which are detachably fitted and engaged with the feed holes b in the lead frame A.
8 are provided along the longitudinal direction of the transfer guide rail 1 at intervals longer than the total length L of the lead frame A, and of the two feed pins, the first feed pin 27 on the near side in the transfer direction is
The second feed pin 28 on the front side in the transfer direction is moved further forward than the first intermittent feed stop position to a first intermittent feed stop position C which is set ahead of the feed position B by an appropriate distance X along the transfer direction. , While the feed head 16 of the intermittent transfer mechanism 10 is moved back and forth between the feed position B and the first intermittent feed stop position C, Reciprocating means for reciprocating forward from the first intermittent feed stop position C by the same distance as the pitch P of the feed holes b in the lead frame A along the longitudinal direction of the transfer guide rail; In addition to the configuration in which the distance of the forward reciprocation of the head 16 is adjustable, the configuration is such that the feeding stroke S of the lead frame A in the feeding mechanism 4 is adjustable, or Serial characterized by being adjustably configure distance X of the return reciprocation of the feed head 16. It is a thing.

[Functions and effects of the invention]

In this configuration, when the lead frame A is supplied to the upper surface of the transfer guide rail 1, the lead frame A is
The feed mechanism 4 transfers the lead frame A in the direction of the intermittent transfer mechanism to a position where the feed hole b at the tip of the lead frame A is located at the feed position B. Next, the intermittent transfer mechanism
The feed head 16 in 10 moves backward by the distance X in the direction of the feed mechanism 4 by the reciprocating means in the state of ascending movement, and then descends by the vertical movement means. Since the feed pin 27 fits into and engages with the feed hole b at the tip of the lead frame A, in this state, the feed head 16 is moved forward by the distance X in the opposite direction by the reciprocating means. By doing
The transfer of the lead frame A is performed by using a feed hole b at its tip.
Can be stopped at a position corresponding to the first intermittent feed stop position C.

Next, the feed head 16 in the intermittent transfer mechanism 10
By moving forward in the transfer direction by one pitch P of each feed hole b in the lead frame A, moving upward, retreating to the original position, and then descending.
The lead frame A can be intermittently transported in a state where each feed hole b stops at a position corresponding to the first intermittent feed stop position C. On the other hand, after the next lead frame A is supplied to the upper surface of the transfer guide rail 1, the next lead frame A is supplied to the feeding mechanism 4.
At the lead frame A in the direction of the intermittent transfer mechanism.
Is transferred to a position where the feed hole b at the tip of the feed position is located at the feed position B.

When the end of the first lead frame A is intermittently transferred to the position of the first feed pin 27, the feed head 16 in the intermittent transfer mechanism 10 is moved upward in the direction of the feed mechanism in a state of moving upward. By retreating by X and then descending by the vertical moving means, the first feed pin 27 fits into and engages with the feed hole b at the tip of the next lead frame A, and at the same time, the second feed pin 27 The feed pin 28 fits into and engages with the feed hole b at the end of the first lead frame A intermittently transferred by the first feed pin 27. Thereafter, the above-described operation is repeated, so that the lead frame is moved. The lead frame is moved at the first intermittent feed stop position C and the second intermittent feed stop Under the conditions that stop at the location of both the position D, it is possible to intermittently moved.

That is, according to the present invention, strip-shaped lead frames can be sequentially and reliably fed one by one to one intermittent transfer mechanism, and at least the feed head provided in the one intermittent transfer mechanism is provided. With two feed pins, at least two lead frames are simultaneously
Since the transfer is carried out intermittently one pitch at a time, it is not necessary to provide a plurality of intermittent transfer mechanisms along the transfer guide rail as in the prior art, so that the apparatus can be significantly reduced in size.

Moreover, in the present invention, in addition to the configuration in which the distance of the forward reciprocation of the feed head 16 is adjustable, the feed stroke S of the lead frame A in the feed mechanism 4 is adjustable, or Feed head
In the case where the lead frame to be handled is changed by adjusting the distance X of the return reciprocating motion at 16, the distance of the forward reciprocating motion at the feed head 16 and the feeding of the lead frame A at the feeding mechanism 4 are changed. The stroke S or the distance X of the return reciprocation in the feed head 16 may be simply increased or decreased according to one pitch of the semiconductor chip mounting portion a in the lead frame or the total length L of the lead frame. When configured to handle, there is an effect that the structure of the entire apparatus can be simplified and the number of operations required for adjustment can be greatly reduced.

〔Example〕

Hereinafter, a description will be given of a drawing in which an embodiment of the present invention is applied to a die bonding step of bonding a semiconductor chip to a lead frame with a conductive paste.

In the figure, reference symbol A denotes a lead frame formed of a thin metal plate made of a magnetic material such as an iron plate and formed into a strip shape having an appropriate length L. The lead frame A has a large number of semiconductor mounting portions a. The lead frame A is formed at intervals of a constant pitch P along the longitudinal direction, and a feed hole b is formed on one side edge of the lead frame A at the same pitch P as the semiconductor mounting portion a.
Drilled at intervals.

Reference numeral 1 denotes a transfer guide rail for guiding the strip-shaped lead frame A along its longitudinal direction,
The transfer guide rail 1 is made of a non-magnetic material such as stainless steel or aluminum, and has a guide wall 1a extending along the longitudinal direction of the transfer guide rail 1 on one side edge in the longitudinal direction. 2 are buried at appropriate intervals along the longitudinal direction, and the lead frame A mounted on the upper surface of the transfer guide rail 1 is magnetically attached to the guide wall surface 1a by the permanent magnet 2 in this state. It is configured to transfer the lead frame A in the longitudinal direction.

Then, on the upper surface of one end of the transfer guide rail 1, the strip-shaped lead frames A stored in the magazine rack 3 are supplied one by one.

Reference numeral 4 denotes a feed mechanism disposed at one end of the transfer guide rail 1, and the feed mechanism 4 is supported by a guide member 5 extending along the longitudinal direction of the transfer guide rail 1 so as to be able to reciprocate. It has a feed base 6 and a feed claw 7 attached to the feed base 6 such that the upper end protrudes from the upper surface of the transfer guide rail 1.

A screw shaft 8 pivotally supported in parallel with the guide member 5 is screwed into the feed table 6, and the screw shaft 8 is rotated forward and reverse by a step motor 9 for feeding, so that the feed table 6 is moved. After being moved forward by an appropriate feed stroke S along the longitudinal direction of the transfer guide rail 1, the transfer guide rail 1 is reciprocated to return to the original position, and is supplied to the upper surface of the transfer guide rail 1. The lead frame A is configured to be fed toward the later-described intermittent transfer mechanism 10 by the appropriate stroke S.

The intermittent transfer mechanism 10 includes a machine frame 11 and a carriage 13 provided on the upper surface of the machine frame 11 via a guide member 12 so as to be able to reciprocate along the longitudinal direction of the transfer guide rail 1.
A screw shaft 14 supported by the machine frame 11 is screwed to the carriage 13 and the screw shaft 14 is rotated forward and reverse by a stepping motor 15 for intermittent feeding, whereby the reciprocation is performed. The platform 13 is configured to reciprocate along the longitudinal direction of the transfer guide rail 1.

A feed head 16 is vertically movably mounted on the front surface of a carriage 13 in the intermittent transfer mechanism 10, and the feed head 16 is urged downward by a spring 17;
A roller 18 is provided on the front surface of the upper end of the frame 16, and an auxiliary head 20 is vertically movably mounted on a vertical guide member 19 erected from the upper surface of the machine frame 11.
Is biased downward by a spring 21, and a roller 22 provided on the rear surface of the upper end of the auxiliary head 20 is brought into contact with the upper surface of an end cam 24 attached to the output shaft of a stepping motor 23 for vertical movement. Further, a support member 25 is attached to the auxiliary head 20 so as to extend in the horizontal direction, and the roller 18 of the feed head 16 is brought into contact with the upper surface of the support member 25, whereby the vertical movement step motor 23 is The feed head 16 is configured to move up and down by the forward and reverse rotations of.

A bracket 26 extending in the longitudinal direction of the transfer guide rail 1 is fixed to the feed head 16 in the intermittent transfer mechanism 10, and both ends of the bracket 26 are closer to the front in the transfer direction of the lead frame A. A first feed pin 27 detachably fitted and engaged with the feed hole b of the lead frame A is provided at an end of the lead frame A. The second engages detachably with the feed hole b
In providing each feed pin 28, the first feed pin
The interval W between the second feed pin 27 and the second feed pin 28 is set to a dimension which is appropriately longer than the overall length L of the lead frame A.

The transfer guide rail 1 includes the intermittent transfer mechanism.
A belt conveyor 29 for the lead frame A is provided at a position forward of the position 10.

In this configuration, when the first lead frame A is supplied to the upper surface of one end of the transfer guide rail 1 as shown in FIG. By moving the lead frame A forward in the direction of the transfer mechanism 10 by the feed stroke S, the lead frame A is moved toward the intermittent transfer mechanism 10 in the first feed direction at the tip of the lead frame A, as shown in FIG. While the hole b is fed to a position corresponding to the feed position B, the feed base 6 with the feed claws 7 in the feed mechanism 4
Moves back to the original position.

Next, the feed head 16 in the intermittent transfer mechanism 10
However, as shown in FIG. 8, the return reciprocation from the first processing position (first intermittent feed stop position) C at the position of the first feed pin 27 in the feed head 16 to the feed position (B) is performed. By retreating after moving backward by the distance X, the first feed pin 27 of the feed head 16 is moved to the first position in the lead frame A as shown in FIG.
It fits and engages with the feed hole b.

Then, when the feed head 16 moves forward by the distance X in a lowered state, the lead frame A
As shown in FIG. 9, the first feed hole b in the lead frame A is transferred to the first processing position (first intermittent feed stop position) C, and the first processing position (First intermittent feed stop position) At the position C, the first of the semiconductor chip mounting portions a in the lead frame A
While the conductive paste is applied to the second semiconductor chip mounting portion a, the second lead frame A is supplied to the upper surface of one end of the transfer guide rail 1.

When the application of the conductive paste to the first semiconductor chip mounting portion a is completed, the feed head
The lead frame A is repeatedly moved forward by one pitch P in the lowered state, then moved up by one pitch P, then moved backward by one pitch P and then lowered, so that the lead frame A is moved by one pitch P as shown in FIG. The semiconductor paste is transferred intermittently by P, and a conductive paste is sequentially applied to each of the semiconductor chip mounting portions a at a first processing position (first intermittent feed stop position) C.

As described above, the first lead frame A is intermittently transferred at the intervals of the respective semiconductor chip mounting portions a,
While passing through the first processing position (first intermittent feed stop position) C, the second lead frame A
The feed mechanism 4 feeds the second lead frame A such that the first feed hole b in the second lead frame A comes to the feed position B.

Next, the feed head 16 in the intermittent transfer mechanism 10
Is moved upward from the first machining position (first intermittent feed stop position) C toward the feeding position B by the distance X of the return reciprocating motion, and then descends. As shown in the figure, the first feed pin 27 of the feed head 16 fits into and engages with the first feed hole b of the second lead frame A, and at the same time, the feed head
After the second feed pin 28 in 16 is fitted and engaged in the first feed hole b in the first lead frame A,
When the feed head 16 moves forward by the distance X for the return reciprocation, the second lead frame A
Is transported such that the first feed hole b in the lead frame A comes to the first processing position (first intermittent feed stop position) C, and at the position of the first processing position C, the second A conductive paste is applied to the first semiconductor chip mounting portion a of the semiconductor chip mounting portions a in the second lead frame A, while the first lead frame A is The first feed hole b is in the second processing position (second intermittent feed stop position)
D, and at this second machining position (second intermittent feed stop position) D, the first semiconductor chip mounting portion a of each semiconductor chip mounting portion a in the first lead frame A is mounted. The semiconductor chip is die-bonded to the part a.

Thereafter, by repeating the above operation, each semiconductor chip mounting portion a in the strip-shaped lead frame A
, The first processing position (first intermittent feed stop position)
After the conductive paste is sequentially applied at the location C, the semiconductor chips are successively die-bonded at the second processing position (second intermittent feed stop position) D. The finished lead frame A is sent out by the belt conveyor 29.

In the above-described configuration, the distance X of the return reciprocation of the feed head 16 in the intermittent transfer mechanism 10, that is, the distance X from the feed position B to the first processing position (first intermittent feed stop position) C is the feed mechanism 4 The feed stroke is S, the distance from the retracted position of the feed claw 7 in the feed mechanism 4 to the first processing position (first intermittent feed stop position) C is Y, and the distance from the rear end of the lead frame A to the first position is Y. When the length of up to 1 feed holes b and L _1, X
= Y- (S + L ₁ ), the lead frame to be handled is, as shown in FIG. 12, the total length dimension L ', the pitch of the semiconductor chip mounting portion a' P ', and the length from the rear end. when instead of the 'lead frame a is a' first feed holes b to the length dimension L ₁ is a stroke in the feed mechanism 4, as shown in FIG. 13, S from the the S '= Y − (X + L ₁ ′), the distance X of the return reciprocation in the feed head 16 is made the same, in other words, without changing the distance X. At the position B, the first feed pitch 27 of the intermittent transfer mechanism can be securely fitted and engaged with the feed hole b 'of the lead frame A'.

When the feed stroke in the feed mechanism 4 is configured to have a constant value of S, in other words, when the feed stroke S in the feed mechanism 4 is configured not to be changed, the lead frame handled is
As shown in FIG. 14, from the lead frame A having the total length L and one pitch P, as shown in FIG. 15, the total length L 'and one pitch P' and the first feed from the rear end. the length of the up hole b when instead of the 'lead frame a is' L ₁ is fed position by the feed mechanism 4,
'While will deviate in this case, the distance of the return reciprocation of the feed head 16 in the intermittent transfer mechanism 10 X' from B B to change the, X '= Y- (S' to + L ₁ ') In this way, the feed hole b 'in the lead frame A' can be adjusted to the first position in the intermittent transfer mechanism 10.
The feed pin 27 can be fitted and engaged.

In addition, when the lead frame to be handled is changed from the lead frame A having one pitch to the lead frame A 'having one pitch P' as described above, the intermittent feeding dimension in the intermittent transfer mechanism 10 is changed. That is, it goes without saying that the distance of the forward reciprocation of the feed head 16 is increased or decreased so as to change the pitch P from the pitch P to the pitch P '.

In this case, the feed base with the feed claw 7 in the feed mechanism 4 is moved by the feed step motor 9 and the feed head 16 in the intermittent transfer mechanism 10 is moved.
Are reciprocated by the intermittent feed step motor 15, so that the reciprocating stroke of the feed base 6 with the feed claw 7 in the feed mechanism 4 and the reciprocating motion of the feed head 16 in the intermittent transfer mechanism 10 are controlled. Since the stroke can be arbitrarily changed by controlling the pulse signal to the input to each of the step motors 9 and 15, the feed stroke in the feed mechanism 4 is changed from S to S 'as described above. Or changing the return distance in the intermittent transfer mechanism 10 from X to X ′, and adjusting the change in the intermittent transfer mechanism 10 from P to P ′. It can be done very easily with high accuracy.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of the present invention, FIG. 1 is an overall longitudinal front view, FIG. 2 is an overall plan view, and FIG. 3 is III-III in FIG.
FIG. 4 is an enlarged sectional view taken along line IV-IV of FIG.
FIG. 5 is an enlarged sectional view taken along the line VV of FIG. 2, FIG.
FIG. 8, FIG. 9, FIG. 9, FIG. 10 and FIG. 11 are enlarged plan views showing the operation state, FIG. 12 and FIG. 13 are enlarged plan views when the lead frame to be handled is changed, FIG. No.
FIG. 15 is an enlarged plan view showing another embodiment. A, A ': lead frame, a, a': semiconductor chip mounting portion in lead frame, b, b ': feed hole in lead frame, 1 ... transfer guide rail, 3 ... magazine rack of lead frame , 4 ... feeding mechanism, 6
… Feed table, 7… Feed claw, 8… Screw shaft, 9… Step motor for feeding, 10… Intermittent transfer mechanism, 11… Machine frame, 13… Reciprocating table, 14… Screw shaft , 15… step motor for intermittent feed, 16… feed head, 18… roller, 20… auxiliary head, 22… roller, 23… step motor for vertical movement, 24… end face cam, 25… support Members, 26 ...
... feed head, 27,28 ... feed pin, B ... feed position, C ... first processing position (first intermittent feed stop position), D
... Second processing position (second intermittent feed stop position).

Continuation of front page (56) References JP-A-58-66341 (JP, A) JP-A-2-121340 (JP, A) JP-A-60-58626 (JP, A) JP-A-49-104568 (JP) , A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B65G 25/00-25/12 H01L 21/50 B23Q 7/06

Claims (1)

(57) [Claims] 1. A transfer guide rail 1 configured to guide a strip-shaped lead frame A having a feed hole b at an interval of an appropriate pitch P along the longitudinal direction thereof, and the transfer guide rail 1 A feed mechanism 4 configured to transfer the lead frame A supplied to the upper surface of the lead frame A to a position where the first feed hole at the tip of each of the feed holes b coincides with a predetermined feed position B along the transfer guide rail; An intermittent transfer mechanism 10 disposed at a position forward of the feed mechanism 4 in the transfer direction. The intermittent transfer mechanism 10 is provided with a feed head 16 which is moved up and down by means of up and down movement. At least two feed pins 27, 28 which are detachably fitted into and engaged with the feed holes b of the lead frame A, are connected to the lead frame A along the longitudinal direction of the transfer guide rail 1. A first feed pin 27 is provided at an interval longer than the total length L of A, and the first feed pin 27 on the front side in the transport direction of the two feed pins is set forward by an appropriate distance X from the feed position B along the transport direction. Intermittent feed stop position C
In the meantime, the second feed pin 28 on the front side in the transfer direction coincides with the second intermittent feed stop position D set further forward than the first intermittent feed stop position, while the intermittent transfer mechanism 10
The feed head 16 returns and reciprocates between the feed position B and the first intermittent feed stop position C, and moves from the first intermittent feed stop position C to the lead frame A along the longitudinal direction of the transfer guide rail. Reciprocating means for reciprocating forward by the same distance as the pitch P of the feed hole b is provided, and furthermore, in addition to a configuration in which the distance of forward reciprocation in the feed head 16 is adjustable, the feeding mechanism 4 Wherein the feed stroke S of the lead frame A is adjustable or the distance X of the return reciprocation of the feed head 16 is adjustable. Transfer device.