JP4459681B2 - Flexible plate-like member supply device, supply method, and bonding device - Google Patents

Description

  The present invention relates to a flexible plate-shaped member supply device and a supply method for feeding a flexible plate-shaped member stored in a supply magazine by a pusher, and a bonding apparatus using the supply device.

  The bonding apparatus includes a die bonding apparatus for die-bonding a semiconductor chip (hereinafter simply referred to as a chip) as an electronic component to a lead frame, for example, as a flexible plate-like member, and a chip die-bonded to the lead frame. There is a wire bonding apparatus or the like for wire bonding.

  Such a bonding apparatus has a bonding head. A bonding tool is provided in the bonding head, and a bonding stage is disposed at a position facing the bonding tool.

  The lead frame is sent out from the supply device to conveying means including a conveying rail. The lead frame sent out to the transport means is transported to a portion facing the bonding stage by the transport means. Thereby, a chip is die-bonded to the lead frame by the bonding head, or wire bonding is performed between the chip and the lead frame.

  The supply device has a supply magazine in which the lead frames are stacked and stored at predetermined intervals. This supply magazine has a box shape in which one end face and the other end face along the direction in which the lead frame is sent out are opened, and one end of the lead frame stored in the supply magazine is pushed by a pusher arranged opposite to the one end face. Press. As a result, the lead frame is sent out from the other end opening of the supply magazine to the transport means and transported.

  The supply magazine is driven up and down by an elevator. When one lead frame is sent out, for example, it is driven by a predetermined dimension downward in the height direction, and the height of the next lead frame is set at a position facing the pusher. Is matched. Thereby, a plurality of lead frames stacked and stored in the supply magazine can be sent out sequentially.

  If the height and parallelism of the supply magazine and the transport means are not exactly the same, or if the lead frame previously sent to the transport means stays in the transport means due to a detection failure or an operator error, the supply magazine The lead frame sent out by the pusher cannot be smoothly transferred to the transport means. In that case, the lead frame may be greatly bent and damaged. In particular, in the case of a lead frame in which chips are die-bonded in advance, the loss caused by the damage may increase.

Therefore, in the conventional supply device that sends out the lead frame from the supply magazine, the pusher is elastically held by a spring, and when the pusher pushes the lead frame, the reaction force received by the pusher is larger than the pushing force. If so, the spring is deformed by the differential pressure to relatively displace the pusher in the backward direction. A mechanical detection method is used in which it is detected that a delivery failure has occurred in the lead frame based on the displacement of the pusher. Patent document 1 is known as such a prior art.
JP-A-4-294549

  However, according to the conventional method for mechanically detecting the differential pressure applied to the pusher, it is difficult to accurately elastically deform according to the differential pressure. Even if the spring has the ability to elastically deform precisely according to the differential pressure, the pusher cannot be accurately slid in the backward direction according to the differential pressure due to fluctuations in the slide resistance of the pusher. is there. That is, it is difficult to set the spring force so that the pusher is displaced by a predetermined distance according to the differential pressure. For this reason, it has been impossible to reliably detect a delivery failure before the lead frame is deformed beyond a predetermined level.

  Moreover, recently, a very thin film of about 0.07 to 0.08 mm may be used as a lead frame. In the case of such a thin and soft lead frame, even if the lead frame is deformed due to defective feeding when it is fed from the supply magazine, the differential pressure between the pressing force and the reaction force at that time is considerably reduced. With mechanical detection methods, it may be difficult to accurately detect deformation of the lead frame.

  The present invention optically detects the feeding failure of the flexible plate-like member from the supply magazine, so that even if the flexible plate-like member is a thin film, the feeding failure is accurately detected. Another object of the present invention is to provide a flexible plate-shaped member supply device, a supply method, and a mounting device using the supply device.

The present invention provides a supply magazine in which both end surfaces are opened and a plurality of flexible plate-like members are housed and held so as to be slidable at predetermined intervals in the vertical direction;
A pusher that pushes one end of the flexible plate-like member stored in the supply magazine in a predetermined direction from one opening side of the supply magazine and feeds it from the other opening;
A sensor that optically detects deformation of the flexible plate-like member pushed by the pusher;
The sensor includes a light projector and a light receiver. The light projector and the light receiver are separated from each other along the longitudinal direction of the flexible plate member, and one end side in the width direction of the flexible plate member and the other. It is arranged separately on the end side,
The light projector outputs a light beam having a predetermined width dimension, the light receiver has a light receiving surface equivalent to at least the width dimension of the light beam, and the flexibility depends on the amount of light incident on the light receiving surface. The flexible plate-shaped member supply apparatus is characterized in that the degree of deformation of the plate-shaped member is determined .

The present invention includes a step of pushing out a flexible plate-like member stored and held in a supply magazine by a pusher, and sending out the supply magazine;
The light projector and the light receiver are separated along the longitudinal direction of the flexible plate member, and are arranged separately on one end side and the other end side in the width direction of the flexible plate member. The light receiver has a light receiving surface equivalent to at least the width of the light beam, and the light beam from the projector is pushed by the pusher by the amount of light incident on the light receiving surface. A step of determining the degree of deformation of the flexible plate-shaped member, and a step of stopping pressing the flexible plate-shaped member by the pusher when it is detected that the flexible plate-shaped member is deformed. The flexible plate-like member supply method is characterized in that.

  According to the present invention, when the flexible plate-shaped member sent out from the supply magazine is deformed and becomes defective in feeding, this can be detected optically by the sensor composed of the projector and the light receiver. It becomes possible to carry out with accuracy.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 4 show a first embodiment of the present invention. FIG. 1 shows a die bonding apparatus as a bonding apparatus for bonding a chip 2 as an electronic component to a lead frame 1 as a flexible plate member, and this die bonding apparatus has a feeder 3 as a conveying means. The feeder 3 includes a pair of transport rails 4 and a feed roller 5 that feeds the lead frame 1 supplied to the transport rail 4 as described later along the transport rail 4 in the direction indicated by the arrow X.

  A supply device 8 having a supply magazine 7 for supplying the lead frame 1 is provided at one end side of the feeder 3, and the other end is fed by the feeder 3, and the chip 2 is bonded on the way as will be described later. A collection magazine 11 for collecting the lead frame 1 is provided. Each magazine 7 and 11 can be driven in the vertical direction by an elevator 12.

  A dispenser 13 and a bonding head 14 having a bonding tool 14 a are sequentially disposed in the middle of the feeder 3 along the feed direction of the lead frame 1. The dispenser 13 supplies an adhesive to the portion of the lead frame 1 where the chip 2 is bonded.

  The bonding head 14 is capable of horizontal reciprocation between the feeder 3 and the chip supply device 15 disposed on the side of the feeder 3 and a bonding stage provided facing the feeder 3. It is also driven in the vertical direction above 16 and above the chip supply device 15.

  The chip supply device 15 has a wafer stage 17 on which a semiconductor wafer 2A divided into a large number of chips 2 is provided. On the side of the wafer stage 17, a wafer magazine 18 in which the wafers 2A are stored in multiple stages is provided. The wafer 2 </ b> A stored in the wafer magazine 18 is supplied to the wafer stage 17 by the supply arm 19.

  The supply magazine 7 of the supply device 8 is formed in a box shape having one end surface and the other end surface opened as shown in FIGS. 2 and 3, and the elevator 12 has one end surface facing the transport rail 4. It is mounted on.

  A plurality of holding grooves 21 are formed on the inner surfaces of both sides of the supply magazine 7 over the entire length in the width direction. The lead frame 1 is held in the holding grooves 21 of opposite heights on both side surfaces by engaging both end portions in the width direction so as to be slidable.

  A pusher 22 is disposed at a predetermined height on the other end face side of the supply magazine 7 that is open. That is, the pusher 22 includes an air cylinder 22a and a push shaft 22b driven in the axial direction by the air cylinder 22a, and is arranged at a predetermined height with the axis line horizontal. When the air cylinder 22a is actuated and the push shaft 22b is driven in the protruding direction as indicated by a chain line in FIG. 2, the push shaft 22b holds the holding magazine 21 at the same height as the push shaft 22b of the supply magazine 7. The rear end of the lead frame 1 is pressed. As a result, the lead frame 1 slides on the holding groove 21 as shown by a chain line in the figure and is delivered to the transport rail 4 of the feeder 3.

  The lead frame 1 delivered to the transport rail 4 is transported to a position facing the dispenser 13 by the roller 5, and after the paste is applied at that position, the lead frame 1 is transported to a position facing the bonding stage 16. The chip 2 is die-bonded at a location where the paste of the lead frame 1 is applied by the bonding tool 14a of the bonding head 14.

  The lead frame 1 pushed out by the pusher 22 from the supply magazine 7 is detected by a sensor 24 shown in FIG. The sensor 24 includes a projector 25 and a light receiver 26.

  The light projector 25 is arranged in the vicinity of the end surface of the supply magazine 7 on the side where the lead frame 1 is sent out, and is disposed on one end side in the width direction of the lead frame 1 with the light projecting surface 25a facing the sending direction. The light receiver 26 is disposed downstream of the light projector 25 in the lead frame 1 feeding direction and on the other end side in the width direction of the lead frame 1 with the light receiving surface 26a facing the light projecting surface 25a. Yes. That is, the light projector 25 and the light receiver 26 are spaced apart from each other at a predetermined interval along the conveyance direction of the lead frame 1 and are disposed across the width direction of the lead frame 1.

The light projector 25 and the light receiver 26 are set so that the center in the height direction of the light projecting surface 25 a and the light receiving surface 26 a is substantially the same as the lead frame 1 sent out from the supply magazine 7. Further, a light beam L having a predetermined width is emitted from the projector 25 as shown in FIGS. The light receiving surface 26a of the light receiver 26 is set to be equal to or larger than the width dimension of the light beam L.
The light beam L emitted from the projector 25 can be received by the light receiver 26 without being blocked by the transport rail 4.

When the rear end is pressed by the push shaft 22 b of the pusher 22, the lead frame 1 delivered from the supply magazine 7 passes between the light projector 25 and the light receiver 26. If the lead frame 1 sent out from the supply magazine 7 is smoothly delivered to the transport rail 4, that is, delivered without deformation, the light beam L emitted from the projector 25 is as shown in FIG. amount corresponding to the thickness of the lead frame 1 by the light-receiving surface 26a of the light receiver 26 is cut off, the portion in the figure indicated by a ₁ and a ₂ is received by the.

  On the other hand, when the parallelism and height of the supply magazine 7 and the transport rail 4 are not precisely matched, and the lead frame 1 sent out from the supply magazine 7 is not smoothly delivered to the transport rail 4, the pusher 2 The lead frame 1 pressed by the push shaft 22b is curved and deformed in the vertical direction along the longitudinal direction.

When the lead frame 1 is curved and deformed in the vertical direction along the longitudinal direction, the light beam L emitted from the projector 25 is blocked at a portion corresponding to the curved width w of the lead frame 1 as shown in FIG. In the same figure, the portions indicated by b ₁ and b ₂ are received by the light receiving surface 26 a of the light receiver 26.

As shown in FIG. 2, a light amount detector 28 is connected to the light receiver 26, and a determination device 29 is connected to the light amount detector 28. The light quantity detector 28 electrically detects the light quantity T received by the light receiver 26. The amount of light T, that is, (b ₁ + b ₂ ) varies depending on the bending width w of the lead frame 1.

The determination unit 29 is set with a set value S corresponding to a predetermined light amount. The determiner 29 compares the light amount T detected by the light amount detector 28 with the set value S, and is pushed out from the supply magazine 7 when the light amount T detected by the light receiver 26 decreases to the set value S. When the lead frame 1 is bent to a predetermined degree, it is determined that a delivery failure has occurred in the lead frame 1, and the delivery of the lead frame 1 by the pusher 2 is stopped based on the determination.

  According to the die bonding apparatus having such a configuration, if there is an error in the parallelism between the supply magazine 7 and the transport rail 4 or the height between the lead frame 1 and the transport rail 4 sent out from the supply magazine 7, When the lead frame 1 is transferred from the supply magazine 7 to the transport rail 4, the lead frame 1 pressed by the pusher 2 does not slide smoothly but curves in the vertical direction.

  When the lead frame 1 sent out from the supply magazine 7 by the pusher 2 is bent by a predetermined amount or more in the vertical direction, this is detected by a change in the amount of light received by the light receiver 26 that receives the light L emitted from the light projector 25 of the sensor 24. Is done.

  That is, when the lead frame 1 is bent in the vertical direction, a part of the light beam L emitted from the light projector 25 is blocked according to the degree of bending, and the amount of light received by the light receiving surface 26a of the light receiver 26 is reduced. The curvature of the lead frame 1 is detected.

  The decrease in the amount of light received by the light receiver 26 changes according to the degree of curvature of the lead frame 1. The degree of curvature, that is, the degree of decrease in the amount of light received by the light receiver 26 is detected by the light amount detector 28, and when the amount of received light falls below the set value S set in the determiner 29, it is determined by the determiner 29. Based on the determination, the pressing operation of the lead frame 1 by the pusher 22 is stopped.

  Therefore, when the lead frame 1 is sent out from the supply magazine 7, even if the lead frame 1 cannot be smoothly sent out due to various causes, that is, even if a feeding failure occurs, the lead frame 1 is bent too much before being damaged. In addition, the feeding operation by the pusher 22 can be stopped.

  The feeding failure of the lead frame 1 is optically detected by a sensor 24 including a projector 25 and a light receiver 26. For this reason, it is possible to accurately detect the curvature generated in the lead frame 1 due to poor feeding, so that the detection accuracy can be increased as compared with the conventional mechanical detection. Moreover, since the detection accuracy can be set by the set value S set in the determiner 29, even a slight curve generated in the lead frame 1 can be detected reliably, and this also detects the detection accuracy. Can be increased.

  Further, since the light projector 25 and the light receiver 26 are arranged at a predetermined interval along the transport direction of the lead frame 1, it is possible to detect the curvature of the lead frame 1 in a wide range in the length direction.

  FIG. 5 is a second embodiment showing a modification of the supply device 8 in the first embodiment. In the second embodiment, it is possible to detect that the lead frame 1 pressed by the pusher 22 is bent due to a feed failure in the supply magazine 7.

  That is, the light projector 25 of the sensor 24 is disposed to face one end surface of the supply magazine 7 of the supply device 8 on the pusher 22 side, and the light receiver 26 is disposed to face the other end surface. The supply magazine 7 is open at one end surface and the other end surface. Therefore, the light beam L emitted from the projector 25 is received by the light receiver 26 through the supply magazine 7.

  The light projector 25 is disposed on one end side in the width direction of the lead frame 1, and the light receiver 26 is disposed on the other end side. Further, the light projector 25 and the light receiver 26 are arranged at the same height as the lead frame 1 pressed by the pusher 22.

  According to such a configuration, the lead frame 1 in the supply magazine 7 is caught in the holding groove 21 when the rear end is pushed by the pusher 22 and pushed out from the supply magazine 7, or the lead frame 1 protruding from the supply magazine 7. When a feeding failure occurs due to the leading end portion of the lead frame being caught on the transport rail 4, at least a portion of the lead frame 1 remaining in the supply magazine 7 is curved.

  When the lead frame 1 is curved in the supply magazine 7, this is detected by the projector 25 and the light receiver 26 arranged on one end side and the other end side of the supply magazine 7 as in the first embodiment. The That is, even if the lead frame 1 is curved in the supply magazine 7, it can be reliably detected. Therefore, even in such a case, the feeding can be stopped before the lead frame 1 is damaged.

  6 to 8 show a third embodiment of the present invention. This embodiment is a modification of the sensor 24. The sensor 24 of this embodiment is the same as the first embodiment in that it includes a projector 25 and a light receiver 26, but the first embodiment is different from the projector 25 and the light receiver 26. The arrangement position of is different.

  That is, as shown in FIGS. 6 and 7, a projector 25 is disposed at the entrance portion of the transport rail 4 so as to face the upper surface side of the lead frame 1 sent out from the supply magazine 7, and on the lower surface side of the lead frame 1. A light receiver 26 is disposed at a position facing the light projector 25. The light projector 25 emits a light beam L having an elongated cross-sectional shape along the feed direction of the lead frame 1, and the light receiver 26 includes a long light receiving surface 26 a corresponding to the cross-sectional shape of the light beam L.

  The lead frame 1 sent out from the supply magazine 7 enters between the light projector 25 and the light receiver 26 as shown by a chain line in FIG. 7 and blocks the light receiver 26 from receiving the light beam L. The lead frame 1 sent out from the supply magazine 7 is transferred to the transport rail 4 and is transported by rollers 5 (shown in FIG. 1) provided on the transport rail 4.

  The progress after the feeding operation is started when the lead frame 1 is delivered from the supply magazine 7 and smoothly delivered to the transport rail 4 and when the delivery failure occurs and delivery is not performed smoothly. The amount of received light received by the light receiver 26 varies with time.

  FIG. 8A shows the normal time when the lead frame 1 is smoothly transferred to the transport rail 4 and the change in the amount of received light, and FIG. 8B shows the time when the feed failure occurs. The change in the amount of received light is shown.

As shown in FIG. 8 (a), if the delivery has been carried out smoothly, the feed when the operation is t ₁ hour from the start has elapsed, between the lead frame 1 projector 25 and the photodetector 26 Get in. Thereby, the amount of light received by the light receiver 26 starts to decrease. When t ₂ hours elapse and the lead frame 1 blocks all the light rays from the projector 25, the amount of received light becomes zero.

In contrast, as shown in FIG. 8 (b), if the delivery is not performed smoothly, when t ₁ hour from feeding operation is started has elapsed, the lead frame 1 and the projector 25 and the light receiver 26 Get in between. Thereby, the amount of light received by the light receiver 26 starts to decrease. However, if the conveyance of the lead frame 1 is hindered by, for example, the conveyance rail 4 at time t ₁ ′ and a feeding failure occurs, the amount of received light decreases until time t ₁ ′, but does not decrease thereafter, and time t ₂ Even after the passage, the light beam L from the light projector 25 cannot be completely blocked by the tip of the lead frame 1. In other words, even after a lapse of t ₂ hours, receiver 26 will continue to light.

  Therefore, it is possible to detect whether or not a feed failure has occurred in the lead frame 1 based on the relationship between the passage of time since the pusher 22 starts sending the lead frame 1 and the amount of light received by the light receiver 26. That is, by measuring the amount of light received by the light receiver 26 after the start of delivery, it is possible to determine whether or not delivery failure has occurred.

The lead frame 1 having the leading end transferred to the transport rail 4 is transported along the transport rail 4 by the rollers 5. Therefore, if it is smoothly conveyed lead frame 1 along the transfer rail 4, as shown in FIG. 8 (a), after reaching the light receiving amount of the light receiver 26 is 0 at time t _2, the lead frame 1 is until time t ₃ when the light beam L from the projector 25 is blocked becomes the light receiving amount is 0.

When the light beam L from the projector 25 by the light receiver 26 over time t ₃ is started to be received, the received light amount is increased gradually. Then, the lead frame 1 at time t ₄ when exiting from between the light receiver 26 and emitter 25, the amount of received light becomes constant.

However, when the lead frame 1 passed to the transport rail 4 is generated bad feed in this transfer rail 4, from the state in which light receiving is blocked in the light receiver 26 by a lead frame 1 is continued, the time t ₃ has elapsed also, may not increase the amount of light received by the light receiver 26, was slightly increased, the amount of light received before the time t ₄ or no longer increases.

If the lead frame 1 has a feeding failure before the entrance of the transport rail 4, light reception by the light receiver 26 is not blocked by the lead frame 1, and the light reception amount continues to be constant. That is, the amount of light received by the light receiver 26 does not decrease even after the time t ₁ has elapsed, or after a slight decrease, the amount of received light does not decrease before t ₂ .

  Therefore, according to this embodiment, whether the lead frame 1 has been sent out from the supply magazine 7, whether the lead frame 1 sent out from the supply magazine 7 has been delivered to the transport rail 4, and whether it has been received by the transport rail 4. Whether the delivered lead frame 1 is smoothly transported along the transport rail 4 or not can be detected.

  In the second and third embodiments, as in the first embodiment, a light amount detector 28 and a determiner 29 are sequentially connected to the light receiver 26 that receives the light beam L from the projector 25. The lead frame 1 feeding operation is stopped based on the determination by the determination unit 29.

  In the third embodiment, the determination unit 29 uses the set value S as the set value S, and when the delivery is performed smoothly, the passage of time from the start of delivery of the lead frame 1 by the pusher 22 and the light receiver 26. The relationship with the amount of light received by is set.

  In the first embodiment, a die bonding apparatus is taken as an example of the bonding apparatus. However, a chip is previously die-bonded to a lead frame, and the electrodes of the chip and terminals formed on the lead frame are connected by wires. The present invention can also be applied to a wire bonding apparatus.

  In the embodiments, the lead frame has been described as an example of the flexible plate-like member. However, the present invention can also be applied to an apparatus for supplying a short thin tape or thin film, such as a flip chip bonder. .

  In the second embodiment, the light projector 25 of the sensor 24 is disposed to face one end surface of the supply magazine 7 of the supply device 8 on the pusher 22 side, and the light receiver 26 is disposed to face the other end surface. The bending of the lead frame 1 located in the supply magazine 7 is detected and the feeding failure is detected. However, by arranging the light receiver 26 further downstream from the entrance of the transport rail 4, the pair of light projectors 25 and light receivers 26 are used. The bending of the lead frame 1 in the supply magazine 7, the bending when the lead frame 1 is transferred to the transport rail 4, and the lead frame 1 transferred to the transport rail 4 smoothly along the transport rail 4. Whether or not it is being transported can be detected.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram of the die-bonding apparatus which shows 1st Embodiment of this invention. The top view of a supply apparatus. The enlarged view which sectioned a part of supply magazine of a supply apparatus. (A) is explanatory drawing of the light reception state of a light receiver when a lead frame is not curved, (b) is explanatory drawing of the light reception state of a light receiver when a lead frame is curved. The top view which shows the supply apparatus of 2nd Embodiment of this invention. The top view of the supply apparatus which shows the 3rd Embodiment of this invention. The side view which shows the light projector and light receiver which are provided in the supply apparatus of FIG. (A) is explanatory drawing which shows the relationship between the time when a feeding failure does not occur in the lead frame and the amount of light received by the light receiver, and (b) the time when the feeding failure occurs when the lead frame is transferred to the transport rail. Explanatory drawing which shows the relationship between the light-receiving amount by a light receiver.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Lead frame, 2 ... Chip | tip, 3 ... Feeder, 7 ... Supply magazine, 8 ... Supply apparatus, 22 ... Pusher, 24 ... Sensor, 25 ... Light projector, 26 ... Light receiver, 28 ... Light quantity detector, 29 ... Determinator .

Claims (3)

A supply magazine in which both end faces are open and a plurality of flexible plate-like members are slidably stored in a vertical direction at predetermined intervals;
A pusher that pushes one end of the flexible plate-like member stored in the supply magazine in a predetermined direction from one opening side of the supply magazine and feeds it from the other opening;
A sensor that optically detects deformation of the flexible plate-like member pushed by the pusher;
The sensor includes a light projector and a light receiver. The light projector and the light receiver are separated from each other along the longitudinal direction of the flexible plate member, and one end side in the width direction of the flexible plate member and the other. It is arranged separately on the end side,
The light projector outputs a light beam having a predetermined width dimension, the light receiver has a light receiving surface equivalent to at least the width dimension of the light beam, and the flexibility depends on the amount of light incident on the light receiving surface. An apparatus for supplying a flexible plate-like member, wherein the degree of deformation of the plate-like member is determined . A step of pushing out the flexible plate-like member stored and held in the supply magazine by a pusher and sending it out of the supply magazine;
The light projector and the light receiver are separated along the longitudinal direction of the flexible plate member, and are arranged separately on one end side and the other end side in the width direction of the flexible plate member. The light receiver has a light receiving surface equivalent to at least the width of the light beam, and the light beam from the projector is pushed by the pusher by the amount of light incident on the light receiving surface. A step of determining the degree of deformation of the flexible plate-shaped member, and a step of stopping pressing the flexible plate-shaped member by the pusher when it is detected that the flexible plate-shaped member is deformed. A method for supplying a flexible plate-like member. The flexible plate-like member is a lead frame, and in the bonding apparatus for bonding electronic components to the lead frame sent out from the supply device,
Bonder the supply device, characterized in that a configuration in which the mounting 1 Symbol claims.

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