JP2013022472A - Light irradiation device and light irradiation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the size of the device getting larger and to fully irradiate the areas corresponding to the convexes and the concaves even if there are convexes and concaves on surfaces to be irradiated.SOLUTION: The light irradiation device 10 irradiates a surface to be irradiated S1 formed of the adhesive layer of an adhesive sheet AS with light. The surface to be irradiated S1 has a first irradiation surface SA and a second irradiation surface SB constituted of a convex set up on the first irradiation surface SA. The light irradiation device 10 is provided with a support means 11 for supporting the adhesive sheet AS, a light emission means 12 facing the surface to be irradiated S1 and having a light emission diode 27 emitting light with a specific wavelength, and a moving means 13 for relatively moving the adhesive sheet AS and the light emission means 12. The light emission means 12 is installed in a way that a light axis AX passing through a center CT of the light emission diode 27 and a focus FC on the surface to be irradiated S1 is diagonal to the first irradiation surface SA. This increases the light irradiation on the second irradiation surface SB.

Description

  The present invention relates to a light irradiation apparatus and a light irradiation method, and more particularly to a light irradiation apparatus and a light irradiation method capable of causing a predetermined photoreaction by irradiating light to a photoreactive object.

  In a processing apparatus for a semiconductor wafer (hereinafter sometimes simply referred to as “wafer”), a protective adhesive sheet is applied to the circuit surface of the wafer to perform back surface grinding, or a dicing tape is applied to a plurality of wafers. A process of dividing into chips is performed. The adhesive sheet used for such treatment employs an ultraviolet curable (photoreactive) adhesive as the adhesive, and after the treatment as described above, ultraviolet rays (light irradiation device) are used to treat ultraviolet rays ( The light is irradiated and the adhesive is cured (photoreaction is caused), so that the adhesive force is weakened and the wafer is easily peeled from the wafer.

  For example, Patent Document 1 discloses the ultraviolet irradiation device. As shown in FIG. 5, the ultraviolet irradiation device 50 in this document includes an ultraviolet light emitting diode 51 and a lens 52 that collects ultraviolet light emitted from the light emitting diode 51. Here, as shown in the figure, when the irradiated object is an adhesive sheet AS, and this adhesive sheet AS is attached to the circuit surface WF1 (lower surface in the figure) of the wafer WF, the center of the light emitting diode 51 is obtained. An optical axis AX (indicated by a one-dot chain line in the figure) passing through the CT and the focal point FC of the condensed ultraviolet ray is set to be orthogonal to the circuit surface WF1.

JP 2007-329300 A

  In the ultraviolet irradiation device 50 of FIG. 5, since the optical axis AX is set to be orthogonal to the circuit surface WF1, the circuit surface WF1 of the wafer WF is secured in order to secure the focal length of the condensing lens 52. The distance HG from the wafer WF to the light-emitting diode 51 in the direction orthogonal to the direction increases, and the vertical width of the ultraviolet irradiation device 50 increases, which in turn increases the size of the device.

  Further, in the ultraviolet irradiation device 50 of FIG. 5, when the wafer WF has the bump BM protruding from the circuit surface WF1, the bonding is performed in the bonding region of the adhesive sheet AS corresponding to the rising surfaces Ba and Bb of the bump BM. The adhesive layer of the sheet AS becomes thicker in the optical axis direction (vertical direction in the figure). For this reason, the ultraviolet ray irradiation amount to the adhesive layer corresponding to the rising surfaces Ba and Bb of the adhesive sheet AS is insufficient as compared with other regions, and the adhesive layer bonded to the rising surfaces Ba and Bb becomes poorly cured. . As described above, when a part of the adhesive layer is hardened, in the subsequent peeling process of the adhesive sheet AS, the wafer WF is damaged or the bump BM is peeled off. There is an inconvenience.

Here, as shown in FIG. 6A, when the adhesive sheet AS is pressed and stuck to the wafer WF while rolling the pressing means RR made of a roller on the adhesive sheet AS, the rising surface Ba of the bump BM In addition to the force Fa pressed in the direction orthogonal to the circuit surface WF1 by the pressing means RR, a force Fb in the direction in which the pressing means RR travels (left direction in the figure) is also applied. That is, when affixing the adhesive sheet AS, the resultant force Fc of the force Fa and the force Fb is added to the rising surface Ba of the bump BM, and the rising surface Ba tends to have a stronger adhesive force of the adhesive sheet AS than other regions. There is. For this reason, the force applied to the wafer WF due to the peeling of the adhesive sheet AS is partially increased on the rising surface Ba, and this also causes a peeling failure such that the wafer WF is damaged.
As shown in FIG. 6B, even if the adherend W0 has the recess MA, when the adhesive sheet AS is pressed and pasted by the rolling of the pressing means RR, the rising surface Ma of the recess MA A force similar to the resultant force Fc generated by the force Fa and the force Fb acts to cause a peeling failure of the adhesive sheet AS.

[Object of invention]
The object of the present invention is to suppress an increase in the size of the apparatus, and even if there are concave portions or convex portions on the irradiated surface, light that can sufficiently irradiate the irradiated surface corresponding to the concave portions or convex portions. An object is to provide an irradiation apparatus and a light irradiation method.

In order to achieve the above object, the present invention is a light irradiation device for irradiating light on a surface to be irradiated in an irradiated body,
The irradiated surface includes a first irradiated surface made of a smooth surface,
A support means for supporting the irradiated body; a light emitting means having a light source capable of emitting light of a predetermined wavelength facing the irradiated surface; and a moving means for relatively moving the irradiated body and the light emitting means. With
The light emitting means is configured to be provided so that an optical axis passing through the center of the light emitting source and the focal point of the light emitting source can be set in an oblique direction with respect to the first irradiation surface.

  In the present invention, the irradiated surface may include a second irradiated surface including at least one concave portion or convex portion provided on the first irradiated surface.

  Moreover, it is preferable to employ a configuration in which a changing unit capable of changing the angle of the optical axis is provided.

Further, the irradiated body is an adhesive sheet affixed to the adherend by pressing means,
The pressing means is provided so as to be able to proceed with pasting by moving in the surface direction of the adherend surface while applying a pressing force in a direction orthogonal to the adherend surface of the adherend,
A configuration in which the light emitting unit is provided so that the direction of the optical axis can be set in the direction of the resultant force of the pressing force by the pressing unit and the force in the moving direction is also preferably employed.

Furthermore, the light irradiation method of the present invention is a light irradiation method for irradiating light on a surface to be irradiated in an irradiated body,
The irradiated surface includes a first irradiation surface and a second irradiation surface including at least one concave portion or convex portion provided on the first irradiation surface,
Supporting the irradiated body;
While the optical axis passing through the center of the light emitting source and the focal point on the irradiated surface is set obliquely with respect to the first irradiated surface, the irradiated body and the light emitting source are moved relative to each other, And a step of irradiating the opposite irradiated surface with light having a predetermined wavelength.

  According to the present invention, the optical axis can be set in an oblique direction with respect to the irradiated surface that is a flat surface, so that the optical axis is set to be orthogonal to the irradiated surface as compared with the light irradiation device set. The distance from the irradiated surface to the light emitting source can be reduced to prevent the apparatus from becoming large.

  In addition, since the direction of the optical axis toward the second irradiation surface composed of a concave portion or a convex portion can be brought close to the orthogonal direction or the direction, it is possible to prevent the light irradiation amount on the second irradiation surface from being insufficient. For example, when the irradiated body is a photoreactive adhesive sheet, the adhesive layer on the second irradiated surface can be cured better. Furthermore, even when the adhesive force of the adhesive sheet is stronger on the second irradiated surface than on the first irradiated surface, the adhesive force on the second irradiated surface can be sufficiently weakened. It is possible to prevent the inconvenience of damaging the kimono.

Moreover, when it has a change means, according to the shape of a 2nd irradiation surface, the angle of an optical axis can be changed easily and for a short time, and this prevents that the light irradiation amount in a 2nd irradiation surface is insufficient. be able to.
Furthermore, when it is possible to irradiate light from the acting direction of the resultant force by the pressing means, it becomes possible to weaken the adhesive force on the second irradiation surface of the adhesive sheet even more efficiently.

The schematic front view of the light irradiation apparatus which concerns on embodiment. The schematic plan view of the said light irradiation apparatus. Explanatory drawing which shows the point which irradiates light to a to-be-irradiated surface. Explanatory drawing similar to FIG. 3 of the light irradiation apparatus which concerns on a modification. Explanatory drawing which shows the point which irradiates the light of the light irradiation apparatus which concerns on a prior art example. (A) And (B) is explanatory drawing which shows the sticking point of the adhesive sheet by a press means.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the present specification and claims, “light” is used as a concept including visible light as well as invisible light including ultraviolet rays.
In this specification, “upper”, “lower”, “left”, and “right” are used with reference to FIG. 1 unless otherwise specified.

  1 to 3, the light irradiation apparatus 10 includes a support unit 11 capable of supporting a wafer WF as an adherend to which an ultraviolet curable adhesive sheet AS (irradiated body) is attached, and the support unit 11. The light-emitting means 12 incorporated therein and a moving means 13 for moving the light-emitting means 12 in the left-right direction are provided.

  The adhesive sheet AS includes a base sheet and an ultraviolet curable adhesive layer that is provided on one surface of the base sheet and adheres to the wafer WF, and the adhesive layer serves as the irradiated surface S1. . Strictly speaking, the adhesive layer is not a surface because it has a thickness, but since the thickness is extremely thin, it is expressed as a surface. The adhesive sheet AS is affixed to the circuit surface WF1 of the wafer WF, and a plurality of bumps BM (see FIG. 3) are formed on the circuit surface WF1 as projecting convex portions. Accordingly, the irradiated surface S1 is composed of a first irradiation surface SA that is a smooth surface attached to the circuit surface WF1, and a second irradiation surface SB attached to the bump BM. The wafer WF is disposed inside the opening of the ring frame RF, and is integrated with the ring frame RF from the opposite surface (upper surface) side of the circuit surface WF1 via the mounting tape MT.

  The support means 11 includes a case body 18 including a bottom wall 15, a peripheral wall 16 and a top wall 17, and four mounting portions 20 on which the ring frame RF is mounted while being installed on the top surface of the top wall 17. And a glass plate 21 provided in the opening of the top wall 17. The support means 11 positions the ring frame RF in the surface direction when the ring frame RF is placed on each mounting portion 20, and supports the adhesive sheet AS via the ring frame RF, the mounting tape MT, and the wafer WF. To come. The opening of the top wall 17 is provided in a shape in which the wafer WF is accommodated when viewed in plan.

  The light emitting means 12 includes a bracket 24 attached to the moving means 13, a light source box 25 rotatably supported on the bracket 24, and light emitting diodes as a plurality of light sources attached in the light source box 25. 27, a light collecting plate 26 for condensing the light of the light emitting diode 27, and a rotation motor 28 as a driving device which is attached to the bracket 24 and serves as a changing means provided to be able to rotate the light source box 25. Yes.

  The light emitting diodes 27 are juxtaposed in the light source box 25 at predetermined intervals in the vertical direction in FIG. A plurality of light emitting diodes 27 may also be provided in the light source box 25 in the left-right direction in FIG. Each light emitting diode 27 is provided so as to be able to irradiate light of a predetermined wavelength, in this embodiment, ultraviolet light, and as shown in FIG. 3, provided by the light collector 26 so that the focal point FC is positioned on the irradiated surface S1. It has been. Here, a straight line passing through the center CT of the light emitting diode 27 and the focal point FC is defined as an optical axis AX. The length of the optical axis AX is a certain length depending on the shape of the light collector 26. The rotation motor 28 is provided so that the inclination angle of the optical axis AX with respect to the first irradiation surface SA can be changed.

  The moving means 13 comprises a linear motion motor 31 as a driving device installed on the bottom wall 15, and a bracket 24 is mounted on the slider 31A. The moving means 13 is provided so that the light emitting means 12 can reciprocate in the radial direction of the wafer WF in a plan view, and the irradiated surface S <b> 1 can be irradiated through the glass plate 21 with the ultraviolet rays emitted from the light emitting diodes 27. .

  Next, a method for irradiating the adhesive sheet AS with ultraviolet rays by the light irradiation device 10 will be described.

  First, the ring frame RF is placed on each placement unit 20 by a conveying device (not shown) so that the adhesive sheet AS is on the lower side. Thereby, the adhesive sheet AS is supported by the support means 11 via the ring frame RF or the like. At this time, as shown in FIG. 1, the light emitting means 12 is in a standby state via the linear motor 31 so as to be positioned on the right side of the right end of the adhesive sheet AS. The issuing means 12 previously rotates the light source box 25 by the operation of the rotation motor 28 to determine the inclination angle θ of the optical axis AX of the light emitting diode 27. As shown in FIG. 3, the inclination angle θ of the optical axis AX is an inclination angle with respect to the first irradiation surface SA, and the optical axis with respect to the second irradiation surface SB bonded to the rising surface Ba on the right side of the bump BM. The AX is set to an orthogonal direction or an angle close thereto.

  Here, the rotation motor 28 is controlled by a control unit (not shown), and the rotation motor 28 is rotated so as to have an inclination angle θ input in advance by an operator via an input unit such as an operation panel (not shown). The distance to the irradiated surface S1 can be detected by a detection means such as a sensor (not shown), and the rotation motor 28 can be rotated based on the detection result. For example, as shown in FIG. 6A, when the adhesive sheet AS is attached to the wafer WF by the pressing means R, the inclination angle θ sets the direction of the optical axis AX in the direction in which the resultant force Fc acts. You can also Here, since the length of the optical axis AX is constant, when the optical axis AX is tilted, the distance HG2 from the wafer WF to the linear motion motor 31 is irradiated as shown in FIG. The distance is shorter than the distance HG1 when ultraviolet rays are irradiated in a direction orthogonal to the surface S1 (indicated by a two-dot chain line on the left side of the figure). Thereby, the width | variety of the up-down direction of the surrounding wall 16 in the case body 18 can be made small, and the enlargement of the light irradiation apparatus 10 can be suppressed by extension.

  Next, in a state where each light emitting diode 27 is caused to emit light, the light emitting means 12 is moved to the left by the operation of the linear motor 31 so as to pass under the adhesive sheet AS. Thereby, it is possible to prevent the irradiated surface S1 from being irradiated with ultraviolet rays, and in particular, the ultraviolet irradiation amount on the second irradiation surface SB adhered to the rising surface Ba can be prevented from being insufficient compared to other regions. Then, after the light emitting means 12 is moved from the left end of the adhesive sheet AS to the left side by the linear motion motor 31, the light source box 25 is rotated by the operation of the rotation motor 28. By this rotation, the direction of the optical axis AX of the light emitting diode 27 is perpendicular to the second irradiation surface SB bonded to the left rising surface Bb, as shown by the two-dot chain line on the right side of FIG. It is changed to an angle close to this. Thereby, it is possible to prevent the UV irradiation amount on the second irradiation surface SB bonded to the rising surface Bb from being insufficient, and in the bonding region of the rising surfaces Ba and Bb on the second irradiation surface SB, The curing reaction can be sufficiently performed. After the ultraviolet irradiation, the ring frame RF is transferred through a transfer means (not shown), and the adhesive sheet AS is peeled from the wafer WF in the peeling step. Thereafter, the same operation as described above is repeated.

  Therefore, according to such an embodiment, it is possible to suppress an increase in the size of the light irradiation device 10 by reducing the width in the vertical direction of the peripheral wall 16 in the case body 18, and adhesion on the second irradiation surface SB. It is possible to sufficiently weaken the adhesive force of the agent, and it is possible to suppress the occurrence of a peeling failure such that the bumps BM are peeled off when the adhesive sheet AS is peeled from the wafer WF. In particular, when the adhesive sheet AS is pressed and pasted by the pressing means RR, the shortage of the ultraviolet irradiation amount on the second irradiation surface SB where the adhesive strength is relatively strong can be eliminated, and the peeling failure of the adhesive sheet AS is further reduced. It becomes possible to prevent well.

As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this.
In other words, the present invention has been illustrated and described mainly with respect to specific embodiments, but without departing from the scope of the technical idea and object of the present invention, the shape, position, or With respect to the arrangement and the like, those skilled in the art can make various changes as necessary.
Therefore, the description limited to the shape disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded one part or all part is included in this invention.

  For example, the light emitting means 12 can be variously modified and can be replaced with the configuration shown in FIG. In the figure, the light emitting means 12 includes a bracket 24 attached to the moving means 13, a substrate 35 rotatably supported by the bracket 24, and on the substrate 35. A light emitting diode 34 as a light source arranged in parallel in the orthogonal direction at predetermined intervals, and a rotation motor 28 as a driving device that is attached to the bracket 24 and serves as a changing means provided to be able to rotate the substrate 35. It has.

  In addition, the moving means 13 moves the adhesive sheet AS or the like to be irradiated without moving the light emitting means 12 by a driving device or adheres to the light emitting means 12 as long as irradiation can be performed as in the embodiment. It is also possible to make both the sheet AS and the like movable and to make them relatively movable.

  Furthermore, in the said embodiment, although the light emission means 12 was reciprocated in the radial direction of adhesive sheet AS, as long as light irradiation amount is enough, it is good also as operation | movement only in any one direction of reciprocation.

  Further, the inclination angle θ may be changed by the operation of the rotation motor 28 while the light emitting means 12 is moved by the moving means 13.

  Furthermore, as another configuration of the pressing means RR, a plate member that presses the adhesive sheet AS while proceeding in the surface direction of the adhesive sheet AS can be exemplified.

  The light source may be another light source such as a high-pressure mercury lamp, a low-pressure mercury lamp, a halogen lamp, a metal halide lamp, or a fluorescent lamp. The light can be adopted.

  Furthermore, the adherend is not limited to the wafer WF, and other objects such as a glass plate, a steel plate, or a resin plate can be used. The semiconductor wafer is a silicon semiconductor wafer or a compound semiconductor wafer. May be. The wafer WF may be other than that integrated with the ring frame RF.

Further, the irradiated surface S1 may be smooth without a concave portion or a convex portion, or may have a plurality of concave portions MA as shown in FIG. In addition to the adhesive sheet AS, the object to be irradiated may be a paint that is cured by irradiating light or ink of a printed material, or a resin that is softened by irradiating light.
Furthermore, the protrusions formed on the wafer WF may be unevenness of the circuit itself in addition to the bumps.

  The drive device in the embodiment includes an electric device such as a rotation motor, a linear motion motor, a linear motor, a single-axis robot, and an articulated robot, an actuator such as an air cylinder, a hydraulic cylinder, a rodless cylinder, and a rotary cylinder. In addition to these, a combination of them directly or indirectly may be employed (some of them overlap with those exemplified in the embodiment).

DESCRIPTION OF SYMBOLS 10 Light irradiation apparatus 11 Support means 12 Light emission means 13 Movement means 27 Light emitting diode (light emission source)
28 Rotating motor (changing means)
AS adhesive sheet (irradiated body)
AX Optical axis CT center FC focus RR pressing means S1 irradiated surface SA first irradiated surface SB second irradiated surface WF semiconductor wafer (adhered body)
WF1 Circuit surface (attachment surface)

Claims (5)

A light irradiation device for irradiating light on an irradiated surface of an irradiated body,
The irradiated surface includes a first irradiated surface made of a smooth surface,
A support means for supporting the irradiated body; a light emitting means having a light source capable of emitting light of a predetermined wavelength facing the irradiated surface; and a moving means for relatively moving the irradiated body and the light emitting means. With
The light emitting device is characterized in that an optical axis passing through the center of the light emitting source and the focal point of the light emitting source can be set in an oblique direction with respect to the first irradiation surface.   The light irradiation apparatus according to claim 1, wherein the irradiated surface includes a second irradiation surface including at least one concave portion or convex portion provided on the first irradiation surface.   The light irradiation apparatus according to claim 1, further comprising changing means capable of changing an angle of the optical axis. The irradiated body is an adhesive sheet affixed to the adherend by pressing means,
The pressing means is provided so as to be able to proceed with pasting by moving in the surface direction of the adherend surface while applying a pressing force in a direction orthogonal to the adherend surface of the adherend,
The said light emission means is provided so that the direction of the said optical axis can be set to the action direction of the resultant force of the pressing force by the said pressing means, and the force of the said moving direction, The said light axis means is characterized by the above-mentioned. Light irradiation device. A light irradiation method for irradiating light on a surface to be irradiated in an irradiated body,
The irradiated surface includes a first irradiated surface made of a smooth surface,
Supporting the irradiated body;
While the optical axis passing through the center of the light source and the focal point of the light source is set obliquely with respect to the first irradiation surface, the irradiated body and the light source are moved relative to each other to face the light source. And a step of irradiating the surface to be irradiated with light of a predetermined wavelength.

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