JP4766258B2 - Pickup device for plate-like article - Google Patents

Description

  The present invention relates to a plate-shaped article pickup device, and more particularly to a plate-shaped article pickup device suitable for picking up a semiconductor chip from an adhesive sheet, for example.

Conventionally, a pickup device for picking up a plate-like article such as a semiconductor chip bonded to an adhesive sheet from the adhesive sheet is known, and as such a pickup device, the adhesive sheet is irradiated with ultraviolet rays. Have been proposed (for example, Patent Document 1 and Patent Document 2).
That is, in the apparatus of Patent Document 1, only the UV adhesive layer corresponding to the chip picked up from below the adhesive sheet is selectively irradiated with ultraviolet rays. Further, it has been proposed to arrange a light diffusing plate below the adhesive sheet and irradiate the adhesive sheet with ultraviolet rays through the light diffusing plate.
In the apparatus of Patent Document 2, ultraviolet rays are irradiated to an adhesive tape on which a thin semiconductor wafer is adhered and supported while swinging an ultraviolet lamp.
JP 2005-302203 A Japanese Patent Laid-Open No. 2001-290000

By the way, the above-described conventional apparatus has the following drawbacks.
That is, in the apparatus of Patent Document 1, a shielding member is disposed between a light source for irradiating ultraviolet rays and an upper chip, and an adhesive corresponding to one semiconductor chip of an adhesive sheet is used by using the shielding member. The location is irradiated with ultraviolet rays. For this reason, in order to support all types of chips with different shapes and sizes, a mechanism that can change the size of the irradiation window of the shielding member is provided, or the shielding member is replaced according to the shape and size of the chip. I had to do it.
Further, Patent Document 2 does not irradiate each semiconductor chip with ultraviolet rays, but irradiates the whole thin semiconductor wafer with ultraviolet rays. And in the apparatus of this patent document 2, since the ultraviolet lamp was used as a light source, since it was difficult to condense an ultraviolet-ray to a specific part, the irradiation time of the ultraviolet-ray was long.
Furthermore, since one semiconductor chip is not irradiated with ultraviolet rays, semiconductor chips other than the specific semiconductor chip to be picked up from the adhesive sheet are also peeled off from the adhesive sheet. For this reason, when a specific semiconductor chip to be picked up is picked up by holding and picking up by the holding means, the specific semiconductor chip and the semiconductor chip at the adjacent position contact each other, and the semiconductor chips are damaged. The shortcoming was pointed out.

In view of the above-described circumstances, the present invention described in claim 1 adheres and supports a plurality of plate-shaped articles on the surface, and adheres the plate-shaped articles to the surface when ultraviolet rays are irradiated from the back side. Pressure-sensitive adhesive sheet, supporting means for supporting the periphery of the pressure-sensitive adhesive sheet, ultraviolet irradiation means for irradiating the pressure-sensitive adhesive sheet with ultraviolet light from its back surface, and suction holding means for sucking and holding the plate-like article The ultraviolet light irradiation means reduces the adhesive force by irradiating the adhesive range where the specific plate-shaped article to be picked up in the pressure-sensitive adhesive sheet is bonded to the adhesive sheet, and the adsorption-holding means reduces the specific plate-shaped article. In a pick-up device for a plate-like article that is picked up from an adhesive sheet,
The ultraviolet irradiation means includes a laser oscillator that oscillates laser light having a wavelength in the ultraviolet region, and a condensing means that condenses the laser light oscillated from the laser oscillator to an irradiation spot that is smaller than the adhesion range of the plate-shaped article; e Bei and scanning means for moving the irradiation spot of the laser beam in the adhesive range of plate-like article in the pressure-sensitive adhesive sheet, further provided with a light-scattering plate for scattering a laser beam between the adhesive sheet and the condensing means The laser beam having a lower energy intensity at the central portion of the cross-section transmitted through the light scattering plate is irradiated onto the adhesion range of the plate-like article in the pressure-sensitive adhesive sheet .

According to the above-described configuration, even if the type of the plate-shaped article that is bonded and supplied to the pressure-sensitive adhesive sheet is changed due to a change in production type or the like, the laser beam can be reliably applied only to the adhesion range of the specific plate-shaped article on the pressure-sensitive adhesive sheet. Can be irradiated. Therefore, the laser beam is not irradiated to the adhesion range of the plate-shaped article adjacent to the specific plate-shaped article, and a plurality of adjacent plate-shaped articles are picked up when the plate-shaped article is picked up from the adhesive sheet. It is possible to prevent contact and damage.
Moreover, even when a plurality of types of plate-like articles are bonded to one adhesive sheet, it can be easily handled.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1 and FIG. 2, reference numeral 1 denotes a pickup device. To be supplied to the next process. In the following description, the horizontal direction that is the left-right direction in FIG. 1 is the X-axis direction, the direction orthogonal to the X-axis direction in the horizontal plane is the Y-axis direction, and the vertical direction is the Z-axis direction.

  The pickup device 1 includes a support member 4 that supports a large number of semiconductor chips 2 cut out from a thin semiconductor wafer, a support unit 5 that moves the support member 4 in the XY axis direction, and a support member. Imaging means 6 for photographing the semiconductor chip 2 on the upper side 4 from above, and ultraviolet irradiation means 7 for irradiating the laser beam L in the ultraviolet region toward the support member 4 installed on the lower side which is the back surface of the semiconductor chip 2; The pick-up device 1 is controlled by a control device 9. The pick-up device 1 is provided with suction holding means 8 for sucking and holding the semiconductor chip 2 from the upper side which is the surface thereof.

As shown in FIG. 3, the semiconductor wafer 2 </ b> A supported by the support member 4 is cut into square semiconductor chips 2 by being cut along a grid-like cutting line by a cutting device (not shown). The thickness of the semiconductor wafer 2A is 20 to 700 μm, and the shape of each semiconductor chip 2 can be freely changed according to the specifications.
Note that the cutting apparatus uses a dicing method such as water jet processing, laser processing, or hybrid laser processing that guides a laser beam into a water jet and cuts the semiconductor wafer 2A supported by the support member 4. The thin plate-like semiconductor wafer 2A is cut into the rectangular semiconductor chips 2 as described above.
When the semiconductor wafer 2A attached to each support member 4 is cut into a large number of semiconductor chips 2 as described above, the cutting device supplies the semiconductor chip 2 to the pickup device 1 in a state of being bonded and held by the support member 4. The pickup apparatus 1 supplies each semiconductor chip 2 held by the support member 4 to the next process apparatus (not shown) one by one by the suction holding means 8.

As shown in FIGS. 1 to 3, the support member 4 includes a ring-shaped wafer ring 11 and the pressure-sensitive adhesive sheet 3 made of an ultraviolet curable UV tape stretched over the wafer ring 11. The semiconductor wafer 2A is bonded and held on the surface (upper surface) of the pressure-sensitive adhesive sheet 3, and the semiconductor wafer 2A is cut into a large number of semiconductor chips 2A by the cutting device as described above while being bonded to the pressure-sensitive adhesive sheet 3. . Thus, each semiconductor chip 2 is adhered and held on the surface by the adhesive force of the adhesive sheet 3.
The pressure-sensitive adhesive sheet 3 has almost no adhesive force when irradiated with ultraviolet rays from the ultraviolet irradiation means 7.
As will be described in detail later, in this embodiment, after the adhesive force of the adhesive sheet 3 in the adhesion range B to which the specific semiconductor chip 2 to be picked up is adhered is reduced, the semiconductor chip 2 is held by the suction holding means 8. Since pick-up is performed by suction holding, the semiconductor chip 2 around the specific semiconductor chip 2 to be picked up is stably held by the pressure-sensitive adhesive sheet 3 when picking up the specific semiconductor chip 2A from the pressure-sensitive adhesive sheet 3. The state is to be maintained.

The support means 5 includes a Y-axis table 14 that moves on a first rail 13 provided in the Y-axis direction, and an X that moves on a second rail 15 provided on the Y-axis table 14 in the X-axis direction. An axis table 16 and a ring support member 17 provided on the X axis table 16 and supporting the wafer ring 11 horizontally are provided. Further, on the inner side of the ring support member 17, a light scattering plate 18 having a size including the bonding range of all the semiconductor chips 2 </ b> A is provided on the support means 5 so as to be superposed on the back surface of the pressure-sensitive adhesive sheet 3.
The back surface (lower surface) of the light scattering plate 18 is a scattering surface on which minute irregularities are formed by blasting or the like. Therefore, by passing the laser light L through the light scattering plate 18, the energy concentrated on the central portion in the cross-sectional direction of the laser light L is dispersed and applied to the adhesive tape 3. By doing so, when the semiconductor chip 2 is picked up from the adhesive tape 3, the adhesive of the adhesive tape 3 is prevented from adhering to the back surface as a residue.
The support means 5 can move the support member 4 in the X-Y axis direction so that the specific semiconductor chip 2 to be sucked and held by the sucking and holding means 8 is positioned at the pickup position A. It has become.
Next, the photographing means 6 is a conventionally known CCD camera, and is arranged above the pickup position A with the vertical downward direction. The photographing means 6 photographs the semiconductor chip 2 on the support member 4 and transmits the image to the control device 9.
The control device 9 recognizes the outline (see FIG. 3) of the semiconductor wafer 2A by image processing based on the image photographed by the photographing means 6, and recognizes the shape and position of the specific semiconductor chip 2. At the same time, the range in which the semiconductor chip 2 is bonded to the pressure-sensitive adhesive sheet 3 is recognized as the bonding range B based on the recognized shape and size of the semiconductor chip 2.

As shown in FIG. 2, the ultraviolet irradiation means 7 collects the laser light L, a laser oscillator 21 that oscillates the laser light L having a wavelength in the ultraviolet region, a scanning means 22 that moves the irradiation spot S of the laser light L, and the laser light L. An fθ lens 23 as a light condensing unit and a light guiding unit 24 for guiding the laser light L to the back surface side of the specific semiconductor chip 2 are provided.
When the laser light L in the ultraviolet region oscillated from the laser oscillator 21 passes through the light scattering plate 18 and is irradiated onto the adhesive sheet 3, the low molecular adhesive of the adhesive sheet 3 is irradiated at the irradiation spot S of the laser light L. As the crosslinking proceeds, the adhesive force is almost completely lost. Then, by moving the irradiation spot S of the laser light L within the bonding range B of one semiconductor chip 2 by the scanning means 22, the adhesive force of the pressure-sensitive adhesive sheet 3 in the bonding range B of one semiconductor chip 2 is reduced. I have to.

The scanning means 22 includes a first galvanometer mirror 25 that moves the irradiation spot S of the laser light L in the adhesion range B of the semiconductor chip 2 in the X-axis direction, and a second galvanometer mirror 26 that moves the irradiation spot S in the Y-axis direction. The first and second galvanometer mirrors 25 and 26 are controlled by the control device 9.
The fθ lens 23 is provided so as to be positioned between the scanning unit 22 and the adhesive sheet 3, and the laser light L oscillated from the laser oscillator 21 is transmitted through the scanning unit 22 and the light guide unit 24 to the back surface of the semiconductor chip 2. When irradiated to the side, the irradiation spot S of the laser beam L is condensed so as to be in a range that is sufficiently narrower than the adhesion range B (see FIGS. 4 and 5).
At this time, in order to prevent the energy intensity of the laser light L at the irradiation spot S from becoming too high, the light scattering plate 18 is disposed on the back surface of the pressure-sensitive adhesive sheet 3. The laser beam L is transmitted through the light scattering plate 18 so that the energy is scattered, the energy intensity at the center of the cross section of the laser beam L is lowered, and the adhesive sheet 3 is irradiated in this state.
As described above, in this embodiment, the energy of the laser light L is dispersed using the light scattering plate 18. However, the energy is obtained by providing a beam homogenizer between the laser oscillator 21 and the first galvanometer mirror 25. May be dispersed.

Next, the light guide unit 24 guides the laser beam L oscillated from the laser oscillator 21 and passed through the scanning unit 22 to the back surface side of the semiconductor chip 2 at the pickup position A, and the two bend mirrors 27 and 28. It has.
The fθ lens 23 is installed between the bend mirrors 27 and 28, and the focal point of the laser light L is near the lower surface of the light scattering plate 18 provided on the back surface of the adhesive sheet 3, as shown in FIG. It is installed to be located.
4 and 5, the control device 9 controls the operation of the first galvanometer mirror 25 and the second galvanometer mirror 26 of the scanning means 22 to irradiate the bonding range B with the laser beam L. The irradiation spot S at that time is moved. That is, FIG. 5 shows a bottom view with the light scattering plate 18 omitted. First, the irradiation spot S is 1 / of the diameter of the laser beam L in the X-axis direction from the upper left corner in the adhesion range B. Laser light L is irradiated in pulses so as to be displaced by two. Then, when reaching the upper right corner, the laser beam L is displaced to the lower side of the drawing in the Y-axis direction by 2/3 of the light diameter of the laser beam L and then to the left side in the X-axis direction. Displace by half the light diameter.
As described above, the adhesive force of the adhesive sheet 3 in the adhesion range B is substantially equal by scanning the laser beam L so that the entire adhesion range B is irradiated with the laser beam L so as to be a substantially zigzag movement trajectory. I try to eliminate it completely.

Further, as a method of scanning the laser beam L with respect to the bonding range B, first, the position of the irradiation spot S of the laser beam L irradiated first is set at the center of the bonding range B as shown in FIG. From there, the irradiation spot S may be moved so as to draw a rectangular spiral movement locus spreading outward. Alternatively, the movement trajectory of the irradiation spot S may be set to be a circular spiral movement trajectory that spreads outward from the center. In addition, although the laser beam L is irradiated in a pulse shape as described above, it may be irradiated continuously.
The movement locus of the irradiation spot S of the laser beam L described above is such that when the photographing means 6 recognizes the shape of the semiconductor chip 2 and recognizes the adhesion range B, the control device 9 recognizes the adhesion range B of the semiconductor chip 2. The optimum movement trajectory of the irradiation spot S is set automatically.

Next, in FIGS. 1 and 2, the suction holding means 8 includes an actuator 32 that is attached to a frame (not shown) and moves the movable arm 31 in the XY axis direction, and an elevating mechanism 33 at the tip of the movable arm 31. And a suction collet 34 that is attached so as to be movable up and down and sucks and holds the surface side of the semiconductor chip 2. The suction collet 34 is connected to negative pressure generating means (not shown). The operations of the actuator 32, the lifting mechanism 33 and the negative pressure generating means are controlled by the control device 9.
The control device 9 operates the actuator 32 to move the suction collet 34 to the position immediately above the pickup position A via the movable arm 31 and operates the lifting mechanism 33 to lower the suction collet 34 by a required amount. ing. At that time, since the controller 9 introduces a negative pressure to the suction collet 34 by the negative pressure generating means, the upper surface of the semiconductor chip 2 at the pickup position A is sucked and held by the lower end portion of the suction collet 34. It has become.

  By this time, the adhesive range B of the adhesive sheet 3 at the location of the semiconductor chip 2 at the pick-up position A has been irradiated with the laser light L and almost no adhesive force. Therefore, after that, when the control device 9 raises the suction collet 34 holding the semiconductor chip 2 via the lifting mechanism 33, the semiconductor chip 2 is picked up from the adhesive sheet 3 very easily. After that, the control device 9 moves the suction collet 34 horizontally by the required amount via the movable arm 31 to transfer the sucked and held semiconductor chip 2 to the release position in the subsequent process, and then the control device 9 Since the introduction of the negative pressure from the negative pressure generating means to the suction collet 34 is stopped, the holding state of the semiconductor chip 2 by the suction collet 34 is released.

The operation of the pickup apparatus 1 of the present embodiment having the above configuration will be described.
First, a large number of semiconductor chips 2A that have been diced from the semiconductor wafer 2A in the cutting device located in the previous process of the pickup device 1 are supplied to the pickup device 1 while being bonded and held to the adhesive sheet 3 of the support member 4. Then, the support member 4 is held by the support means 5.
The support means 5 moves the Y-axis table 14 and the X-axis table 16 to move the specific semiconductor chip 2 to be picked up to the pickup position A directly below the photographing means 6.

At this time, the suction collet 34 in the suction holding means 8 is positioned above by the elevating mechanism 33, and the suction collet 34 is retracted to a position off the pickup position A via the movable arm 31.
In this state, the photographing means 6 photographs the range including the semiconductor chip 2 located at the pickup position A, and the control device 9 recognizes the outer shape of the specific semiconductor chip 2 from the photographed image, and determines the shape of the semiconductor chip 2. Recognize the size.
Further, the control device 9 recognizes the recognized shape and size of the semiconductor chip 2 as the adhesion range B of the semiconductor chip 2, and the irradiation spot S of the laser light L by the ultraviolet irradiation means 7 within the adhesion range B. The movement trajectory for scanning is set.

Next, the control device 9 irradiates the irradiation spot S of the laser light L oscillated from the laser oscillator 21 near one of the four corners of the bonding range B of the semiconductor chip 2. The two galvanometer mirrors 25 and 26 are moved to activate the ultraviolet irradiation means 7 to oscillate laser light L having a wavelength in the ultraviolet region from the laser oscillator 21.
Subsequently, the control device 9 controls the scanning unit 22 to move the irradiation spot S so as to draw a zigzag movement locus within the adhesion range B as shown in FIG. Thereby, the crosslinking of the pressure-sensitive adhesive of the pressure-sensitive adhesive sheet 3 proceeds along the movement locus of the irradiation spot S, and the pressure-sensitive adhesive force of the pressure-sensitive adhesive sheet 3 in the entire adhesion range B is reduced and the pressure-sensitive adhesive force is almost lost.

In parallel with the irradiation of the laser beam L, the control device 9 operates the actuator 32 and the lifting mechanism 33 of the suction holding means 8 so that the suction collet 34 is located at the pickup position A via the movable arm 31. And the suction collet 34 is lowered, a negative pressure is introduced into the suction collet 34 via the negative pressure generating means, and the semiconductor chip 2 at the pickup position A is sucked and held by the suction collet 34.
Thereafter, when the laser beam L is irradiated to the entire bonding range B, the control device 9 raises the suction collet 34 via the lifting mechanism 33, and the semiconductor chip 2 sucked and held on the suction collet 34 is adhered to the adhesive sheet 3. Is picked up very easily. Thereafter, the control device 9 moves the suction collet 34 to the release position of the next process via the movable arm 31 and further stops the introduction of the negative pressure from the negative pressure generating means to the suction collet 34, so that the semiconductor chip 2 is supplied to a release device for the next process (not shown).

Then, when the new semiconductor chip 2 to be picked up next by the support means 5 is positioned at the pickup position A, the control device 9 uses the ultraviolet irradiation means 7 to position the semiconductor chip 2A positioned at the pickup position A as described above. The laser beam L is irradiated to the adhesion range B on the back surface of the adhesive sheet 3 and the irradiation spot S is moved. Thereby, the pressure-sensitive adhesive sheet 3 in the adhesion range B of the semiconductor chip 2 at the pickup position A is lowered until the pressure-sensitive adhesive force is almost lost.
Further, the control device 9 moves the suction collet 34 to above the semiconductor chip 2 at the pickup position A via the movable arm 31, and lowers the suction collet 34 by the lifting mechanism 33, so that the negative pressure is applied to the suction collet 34. To introduce. As a result, the semiconductor chip 2 is sucked and held by the suction collet 34.
Thereafter, when the suction collet 34 is raised by the control device 9 via the lifting mechanism 33, the semiconductor chip 2 held by the suction collet 34 is picked up from the adhesive sheet very easily. After that, the suction collet 34 and the semiconductor chip 2 held by the suction collet 34 are transferred to the release position of the next process through the movable arm 31, and then the held state is released.
In this way, the semiconductor chip 2A to be picked up is moved to the pickup position A, the back surface of the adhesive tape 3 in the bonding range B of the semiconductor chip 2 is irradiated with the laser light L, and the semiconductor chip 2 is adsorbed by the adsorbing collet 34. The operations of holding and further picking up the semiconductor chip 2A from the adhesive sheet 3 and then transferring to the next process are repeated, so that the semiconductor chips 2 positioned at the pickup position A are sequentially picked up from the adhesive tape 3. ing.

Next, FIG. 7 shows a second embodiment of the present invention. That is, in the first embodiment, the light scattering plate 18 is superposed on the back surface including the entire area where the semiconductor chip 2 of the adhesive sheet 3 attached to the wafer ring 11 of the support member 4 is bonded and held. However, in this second embodiment, the light scattering plate 42 is sized to cover only the adhesion range of the semiconductor chip 2 at the pickup position A and its periphery, and the upper part of the casing 7A in the ultraviolet irradiation means 7 A cylindrical support bracket 41 is fixed to the upper opening 41A of the support bracket 41, and the light scattering plate 42 is connected horizontally. Other configurations are the same as those of the first embodiment, and the corresponding members are denoted by the same member numbers.
Even in the second embodiment, it is possible to obtain the same effects as those of the first embodiment described above.

In each of the above-described embodiments, first, when the adhesive force of the adhesive tape 3 in the adhesive range B is reduced by first irradiating the adhesive range B of the adhesive tape 3 with the laser light L, Although the semiconductor chip 2 is sucked and held by the suction collet 34, the semiconductor chip 2 </ b> A may be sucked and held by the suction collet 34 before the adhesive sheet 3 is irradiated with the laser light L, or a specific semiconductor chip 2 </ b> A is bonded. After irradiating the entire region B with the laser beam L, the suction collet 34 may be lowered to hold the semiconductor chip 2A by suction.
In the above-described embodiment, the two galvanometer mirrors 25 and 26 in the scanning unit 22 are operated to move the irradiation spot S of the laser light L within the bonding range B. It is also possible to move S. For example, the ultraviolet irradiation means 7 is guided so that the laser oscillator 21 and a beam homogenizer that makes the intensity distribution in the cross section of the oscillated laser beam L uniform, or the laser beam L is irradiated to the bonding range B. The light guide means 24 composed of a plurality of bend mirrors that emit light, and the XY table as the scanning means 22 that translates the laser oscillator 21 and the light guide means 24 integrally may be used. .

The front view which shows one Example of a present Example. Sectional drawing of the principal part in alignment with II-II of FIG. The top view of the principal part shown in FIG. The enlarged view of the principal part of FIG. The bottom view of the state which abbreviate | omitted the light-scattering board 18 in FIG. The bottom view which shows the other Example at the time of irradiating the adhesive sheet 3 with the laser beam L by the ultraviolet irradiation means 7 shown in FIG. The front view which shows 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pick-up apparatus 2 ... Semiconductor chip (plate-shaped article)
DESCRIPTION OF SYMBOLS 3 ... Adhesive sheet 7 ... Ultraviolet irradiation means 8 ... Adsorption holding means 21 ... Laser oscillator 22 ... Scanning means 23 ... f (theta) lens (Condensing means)
A ... Pickup position B ... Adhesion range L ... Laser beam S ... Irradiation spot

Claims (2)

Adhering and supporting a plurality of plate-like articles on the surface, and supporting the surroundings of the pressure-sensitive adhesive sheet in which the adhesive strength of the surface to which the plate-like article is adhered decreases when irradiated with ultraviolet rays from the back side Means, ultraviolet irradiation means for irradiating the adhesive sheet with ultraviolet rays from its back surface, and suction holding means for sucking and holding the plate-like article,
The adhesive area is reduced by irradiating UV to the adhesion range where the specific plate-shaped article to be picked up in the pressure-sensitive adhesive sheet is adhered by the ultraviolet irradiation means, and the specific plate-shaped article is adhered to the pressure-sensitive adhesive sheet by the adsorption holding means. In the pick-up device for the plate-like article that is picked up from
The ultraviolet irradiation means includes a laser oscillator that oscillates laser light having a wavelength in the ultraviolet region, and a condensing means that condenses the laser light oscillated from the laser oscillator to an irradiation spot that is smaller than the adhesion range of the plate-shaped article; e Bei and scanning means for moving the irradiation spot of the laser beam in the adhesive range of plate-like article in the pressure-sensitive adhesive sheet, further provided with a light-scattering plate for scattering a laser beam between the adhesive sheet and the condensing means An apparatus for picking up a plate-like article characterized by irradiating the adhesive range of the plate-like article on the pressure-sensitive adhesive sheet with a laser beam transmitted through the light scattering plate and having a reduced energy intensity at the center of the cross section . 2. The plate-shaped article pickup device according to claim 1, wherein the ultraviolet irradiation means includes a beam homogenizer that makes the intensity distribution in the cross-sectional direction of the laser light uniform.

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