JPH07105404B2 - Die bonding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a die bonding apparatus which uses a wafer ring and sequentially takes out semiconductor pellets attached on an adhesive tape to perform a die bonding operation.

(Prior art) When mounting using an adhesive tape and a wafer ring, it is common to cut the uncut pellets to a full cut amount of 0 to 40μ, break from the back side, and then push up to separate the pellets. It is a target, and in this push up,
In order to discriminate the position of pellets and prevent chipping of the pellets, it is generally performed to slightly stretch the tape so that the interval between the pellets is about 60 to 100 μ. This is generally the same wafer ring, even when using the same adhesive tape, the amount of extension of the adhesive tape depending on the outer diameter size and pellet size of the wafer, and thus the interval between pellets changes, for example, the smaller the wafer size, Also, the smaller the pellet size, the smaller the inter-pellet spacing tends to be. On the other hand, in order to pick up the separated pellets from the adhesive tape, interference between the pellets at the time of pickup and interference between the suction jig and the pellets are required. In order to prevent chipping, the larger the interval between pellets is, the better.However, if it is too large, a uniform stretch of the adhesive tape cannot be obtained, and meandering occurs between the pellets.
Or, it is necessary to mechanically correct the position, and when the interval between pellets is set small, it is possible to pick up at a constant feed pitch that is close to the dicing pitch, and work efficiency improves, but the above pellet size and wafer size Also, the amount of elongation changes depending on the type of the adhesive tape, and if the amount of expansion changes to a smaller one, there is a risk of pellet breakage.

For this reason, conventionally, as shown in FIGS. 5 and 6, an adhesive tape 2 is stretched inside a wafer ring 1 and a plurality of semiconductor pellets 3, 3 ... After attaching and braking, the tape is placed on the upper surface of the tape receiving stand 4, and brought into contact with the stoppers 5 and 5 for positioning, and then the wafer ring 1 is pushed down by a predetermined stroke S and rocked. By swinging and locking the free chuck claws 6,6, the peripheral edge of the adhesive tape 2 is extended to secure the interval δ between the semiconductor pellets 3,3, and in this state, the semiconductor pellets 3,3 are sequentially It was generally practiced to take out ... and perform die bonding work.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional example, in order to maintain an appropriate pellet interval δ according to the pellet size, the wafer size, the type of the adhesive tape, etc. It is necessary to prepare and replace the jig, or to prepare an adjustable jig whose stroke S can be adjusted, and adjust the stroke S each time. Therefore, not only does the operating rate of the device decrease, but also after bonding. There was also a quality defect that the inspection of was essential.

In view of the above-mentioned drawbacks, the present invention, in accordance with the conditions of the process, the stretching error of the interval between pellets caused by the difference in the individual devices, the difference in the conditions of the semiconductor process, the difference in the quality of the adhesive tape, etc., can be quickly and automatically adjusted to an arbitrary amount. The purpose of the present invention is to provide an automated die bonding apparatus with high versatility that can be modified dynamically.

[Structure of Invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention drives a stretching motor to stretch the periphery of the adhesive tape, thereby providing an interval between the semiconductor pellets attached to the upper surface of the adhesive tape, In a die bonding apparatus for sequentially taking out the pellets and performing a die bonding operation, an input unit for inputting a stretch amount of the adhesive tape and an interval between pellets, and a memory for storing the stretch amount and the interval between pellets input to the input unit. Section and the amount of stretching stored in this storage unit, the stretching motor is driven by an amount commensurate with the stretching amount, and at least one of the intervals between pellets after stretching is driven by the driving of the stretching motor is measured by a detector. Then, this measured value is compared with the interval between pellets stored in the storage unit, and stretched so that the difference between them is within the allowable range. And an enlargement control unit for correcting the drive of the motor.

(Operation) According to the present invention configured as described above, an appropriate inter-pellet interval corresponding to a pellet size, a wafer size, or the like that is input and stored in advance, and an actual pellet after stretching of the adhesive tape The stretching amount of the adhesive tape can be automatically corrected so that the difference from the interval is within the allowable range.

(Embodiment) FIGS. 1 to 4 show an embodiment of the present invention, in which 10 is a hollow substantially cylindrical tape holding ring, and the periphery of the adhesive tape 2 is provided on the upper surface of the ring 10. The wafer ring 1 is placed in contact with each other, and a push-up holder 11 and a push-up pin 12 for sequentially pushing up the semiconductor pellets 3 and separating them from the adhesive tape 2 are arranged inside. A wafer ring holder 14 is provided on the outer peripheral surface with an intermediate ring 13 interposed therebetween. The holding ring 10 is rotatably supported on the support base 15 on the lower surface of the flange portion 10a, and the rotation preventing rods 16a and 16b are respectively inserted between the holding ring 10 and the intermediate ring 13 and the ring holder 14. The coil spring is constructed so that the three members rotate together as a unit, and a coil spring is urged outward between the retaining ring 10 and the intermediate ring 13.
17 are installed.

A guide groove 14a for positioning the wafer ring 1 is formed on the upper surface of the ring holder 14 and is closed by a hollow disc-shaped lid 18 and the intermediate ring 13 is formed.
A ring-shaped elastic body 19 is fixed to the upper surface of the.

Then, normally, the ring holder 14 is raised by the elastic force of the coil spring 17, and in this state, the wafer ring 1 is inserted under the lid 18 using the guide groove 14a as a guide, and then the ring holder 14 is attached. By lowering, the wafer ring 1 is pressed downward by the lid 18 and pushed down, and the peripheral edge of the adhesive tape 2 is stretched. The length of the adhesive tape portion 2a from the outer peripheral end of the semiconductor pellet 3 to the end of the wafer ring 1 becomes shorter as the size of the wafer increases.

On the side surface of the flange portion 10a of the retaining ring 10, the gear 20
Is fixed, the gear 20 meshes with a pinion 22 fixed to the rotation shaft of the θ motor 21, and the holding ring 10 and the ring holder 14 are integrally rotated with the rotation of the θ motor 21. There is.

Further, a roller groove 14b is provided on the side surface of the ring holder 14, and the roller groove 14b is rotatably and pivotally attached to the bracket 23 standing on the support base 15 via a rotary shaft 24. Further, a pair of rollers 26, 26 rotatably supported are fitted to the tip of the branching stretching arm 25. Further, the rear end of the stretching arm 25 is provided with a roller 30 in a groove 29a of a feed nut 29 which is screwed into a feed screw 28 connected to a stretching motor 27.
The extension arm 25 is swung by the rotation of the stretching motor 27, and the ring holder 14 and the intermediate ring 13 are integrally moved up and down in accordance with this swing.

Then, by controlling the number of rotations of the stretching motor 27, the stretching amount of the adhesive tape 2, that is, the ring holder 14
The stroke S is adjustable.

Reference numeral 31 is a detector for detecting the position of the semiconductor pellets 3, 3, ..., Determining pass / fail, and measuring the interval δ between pellets. The detector 31 is provided above the push-up holder 11 and is provided in a controller 32 for controlling the amount of expansion. It is connected. On the other hand, the control unit 32 is connected to a storage unit 34 for storing the inter-pellet interval previously input to the input unit 33, and the output of the control unit 32 is the θ motor.
21 and the expansion motor 27.

Then, the inter-pellet interval δ detected by the detector 31 and the inter-pellet interval previously input to the input unit 33 and stored in the storage unit 34 are compared by the control unit 32, and the difference between the two is within the allowable range. Thus, the expansion motor 27 is controlled and adjusted.

That is, once the stretching motor 27 is operated based on the data once set in the storage unit 34 and the ring holder 14 is lowered by the stroke S to stretch the peripheral edge of the adhesive tape 2, and then the corners of the semiconductor pellets 3, 3 ,. By detecting the position of the pellet by the detector 31 at two points separated from the parts 36, 36, it is detected whether or not the wafer ring 1 is inserted in an inclined state, and the θ motor 21 is operated and held. The rotation position is corrected by rotating the ring 10 and the ring holder 14 to rotate the wafer ring 1, and the semiconductor pellets 3, 3 ...
The horizontal spacing δ ₁ and the vertical spacing δ ₂ of the corner portion 36 of the detector 31 are detected by the detector 31, and are input to the input unit 33 in advance, and are compared by the stored pellet-to-pellet spacing and the control unit 32, respectively. The stroke motor S is corrected by controlling the expansion motor 27 so that the difference is within the allowable range.

Reference numeral 37 is a pass / fail mark provided in the central portion 38 of the semiconductor pellet 3, and the presence / absence of this mark is detected by the detector 31 to determine pass / fail.

The support base 15 is fixed to the upper surface of a Y table 40 which can be moved back and forth by a motor 39, and the Y table 40 is placed on an X table 42 which can be moved left and right by a motor 41.

In addition, a storage magazine 43 for storing the wafer ring 1
Is provided, and a guide rail 44 is installed between the storage magazine 43 and the Y table 40 to store the storage magazine 43.
The wafer ring 1 therein is configured to be supplied onto the ring holder 14 along the guide rails 44, the semiconductor substrate 45 is disposed on the opposite side, and the semiconductor substrate 45 is provided on the die bonding head 46. After applying the resin supply arm 47 for applying the semiconductor resin to the mounting position C and the semiconductor resin, one semiconductor pellet 3 is taken out by vacuum suction at the pickup position B, and the semiconductor pellet 3 is transferred to the semiconductor at the mounting position C. A bonding arm 48 that is movable back and forth in synchronization with the resin supply arm 47 that is die-bonded to the substrate 45 is provided.

Next, the operation of the present invention will be described with reference to FIG.

First, the X table 42 and the Y table 40 are moved to the wafer ring exchange position, and in this state, a drive system (not shown) is operated to pass the guide rail 44 and guide groove 14a to guide the wafer ring 1 to the ring holder 14. A wafer ring supply operation for guiding and bringing the stopper 5 into contact with the stopper 5 is performed. Next, based on the data set in the storage unit 34, the control unit 32 operates the stretching motor 27 while controlling it, so that the ring holder 14 is lowered via the roller 26 at the tip of the stretching arm 25 and the lid 18 By pressing the wafer ring 1 downward with a predetermined stroke S, the adhesive tape stretching operation of stretching the peripheral edge of the adhesive tape 2 is performed, and at the same time, the Y table 40 and the X table are moved.
The table 42 is moved to the pickup position B.

Next, the Y table 40 and the X table 42 are moved to detect the pellet position at the corner 36 by the detector 31 at two points apart from each other, and the semiconductor pellet 3 is inserted and attached to the ring holder 14 in an inclined state. If it is rotating, activate the θ motor 21 to activate the ring holder.
Perform the correction operation to rotate 14. After this correction, the detector 31
The horizontal interval δ ₁ and the vertical interval δ ₂ of the corner portion 36 of the semiconductor pellets 3, 3 ... Are detected with, and these values stored in the storage unit 34 are compared with the control unit 32. The stroke motor 27 is controlled to correct the stroke S so that
A correction operation for correcting the amount of expansion of the adhesive tape 2 is performed.

Next, after performing the wafer ring centering operation for detecting the center of the wafer ring 1 with the detector 31, the semiconductor pellet
The pitch of 3, 3, ..., That is, the center interval in the vertical and horizontal directions is corrected.

After the above-mentioned preparation is completed, while the Y table 40 and the X table 42 are moved, as shown in FIG. 3, the normal die bonding work is performed while the positioning by the corner portion 36 and the quality judgment by the central portion 38 are sequentially performed. is there.

In the above embodiment, the stretching of the adhesive tape 2 is shown by so-called screw driving, but it goes without saying that it may be performed by other driving such as a cylinder, and the adhesive tape stretching correction operation is performed by rotating the wafer ring. It may be performed together with the stretching operation of the adhesive tape before the correction operation.

〔The invention's effect〕

Since the present invention has the above-mentioned configuration, the expansion error of the semiconductor pellet caused by the individual difference as the apparatus, the difference in the condition of the semiconductor process, the difference in the quality, etc. can be automatically corrected to an arbitrary expansion amount according to the process condition. In addition to being able to cope with the same optical magnification regardless of the size of the semiconductor pellet, it is not necessary to change the size of the pellet quality determination mark according to this size. Therefore, there is an effect that the operating rate can be increased, the quality can be improved, and the versatility can be enhanced.

In addition, since it is equipped with a detector that can detect the surface state of the semiconductor pellets and the interval between the semiconductor pellets, it is possible to detect whether or not the wafer ring is mounted in an inclined state, such as by detecting the pellet interval. A detector used for detecting the position of pellets necessary for measurement and for detecting the presence or absence of the quality mark provided in the center of the semiconductor pellet can also be used for detecting the interval between semiconductor pellets. As a result, the detector can be used for multiple purposes,
The device can be made compact.

In addition, since the pellet interval between the semiconductor pellets adjacent to each other at a predetermined position among the formed pellet intervals is measured by the detector, the pellet interval is relatively large as the adjacent semiconductor pellets at the predetermined position. It is possible to empirically know the adjacent semiconductor pellets in the region that tends to become narrow, and to measure the interval between the adjacent semiconductor pellets. Therefore, empirically knowing the adjacent semiconductor pellets in the region where the pellet spacing tends to be relatively narrow,
By measuring the distance between the adjacent semiconductor pellets, the working efficiency of dicing can be improved.

Further, since the distance between the adjacent semiconductor pellets is measured, the measurement target can be easily put in the visual field of the detector, and it is not necessary to forcibly expand the visual field.

Further, the measured value and the interval between pellets stored in the storage unit are compared, and the distance between the two is stretched so that the difference is within an allowable range so that the motor drive is corrected. Can be controlled with high precision.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 is a schematic vertical sectional front view showing a main portion, FIG. 2 is a plan view showing an outline of the whole, and FIG. 3 is an inside view of a wafer ring. An enlarged plan view showing a part, FIG. 4 is an explanatory view showing operation timing, FIGS. 5 and 6 show a conventional example, and FIG. 5 is a plan view showing a state in which a wafer ring is mounted on a dedicated stretching jig. 6 and 6 are sectional views taken along line VI-VI in FIG. 1 ... Wafer ring, 2 ... Adhesive tape, 3 ... Semiconductor pellet, 10 ... Tape holding ring, 18 ... Lid, 20
...... Gear, 21 …… θ motor, 22 …… pinion, 25 …… Expansion arm, 27 …… Expansion motor, 28 …… Feed screw, 29
...... Feed nut, 31 …… Detector, 32 …… Control section, 33 ……
Input part, 34 ... Storage part, 45 ... Semiconductor substrate, 46 ... Die bonding head, .delta., .Delta.1, .delta.2 ... Space between pellets, S ... Stroke.

Claims (1)

[Claims] 1. A die bonding apparatus for driving a stretching motor to stretch a peripheral edge of an adhesive tape to leave an interval between semiconductor pellets attached to an upper surface of the adhesive tape, and sequentially taking out the semiconductor pellets to perform a die bonding operation. In, an input unit for inputting the stretch amount of the adhesive tape and the interval between pellets, a storage unit for storing the stretch amount and the interval between pellets input to the input unit, and the surface state of the semiconductor pellet can be detected. With a detector that measures the inter-pellet interval between adjacent semiconductor pellets at a predetermined position, and compare the measured value of the inter-pellet interval detected by the detector and the inter-pellet interval stored in the storage unit. And a stretching control unit that corrects the motor drive so that the difference between the two is within the allowable range. Die bonding apparatus according to claim.