JP7567156B2 - Workpiece dividing device - Google Patents

Description

The present invention relates to a workpiece dividing device, and in particular to a workpiece dividing device that expands a dicing tape after dicing the workpiece to divide the workpiece into individual chips.

Conventionally, in the manufacture of semiconductor chips, a workpiece dividing device is known that divides a semiconductor wafer into individual chips by, for example, attaching the semiconductor wafer, inside which a dividing line has been formed in advance by laser irradiation or the like, to a dicing tape and expanding the dicing tape (see, for example, Patent Document 1).

The portion of the dicing tape that is expanded by the workpiece dividing device remains in an expanded and loose state even after the workpiece is divided. If the workpiece is transported in this state, the individual chips on the dicing tape may come into contact with each other or may be subjected to excessive bending stress.

Therefore, in order to solve the above problem, the workpiece dividing device of Patent Document 1 is equipped with a selective heating means that selectively heats the dicing tape that has become loose due to expansion and re-tensions it. In addition, the above-mentioned workpiece dividing device employs a halogen lamp heater as an example of the selective heating means.

JP 2017-123476 A

However, the workpiece dividing device in Patent Document 1 has the following problems:

In other words, when a halogen lamp heater is used as the selective heating means and a dicing tape with high infrared light transmittance is used, the heat from the halogen lamp heater may not be sufficiently transferred to the loosened portion, and the loosened portion may not be heated efficiently. In this way, the workpiece dividing device of Patent Document 1 may not be able to heat the loosened portion efficiently, and therefore may not be able to reliably tension the loosened portion.

The present invention was made in consideration of these circumstances, and aims to provide a workpiece dividing device that can efficiently heat loosened parts of the dicing tape and reliably tension them.

In order to achieve the object of the present invention, the workpiece dividing device of the present invention expands a dicing tape and divides a workpiece attached to the dicing tape into individual chips. The workpiece dividing device includes an expanding means for expanding the dicing tape and a heating means for heating the slackened portion of the dicing tape due to the expansion. The heating means includes a light irradiating means for irradiating infrared light toward the slackened portion, and a light reflecting means arranged opposite the light irradiating means across the slackened portion, and for reflecting the infrared light that has passed through the slackened portion toward the slackened portion.

According to one embodiment of the present invention, the light irradiating means has a light source that emits infrared light and an optical member that irradiates the slackened portion with the infrared light emitted from the light source, and the light reflecting means preferably includes a concave mirror.

According to one embodiment of the present invention, the light irradiating means has a light source that emits infrared light and an optical member that irradiates the slackened portion with the infrared light emitted from the light source, the light reflecting means is configured in a semicircular tube shape formed to correspond to the annular shape along the outer periphery of the work, and the light irradiating means has a reflector member, and the reflector member preferably includes a reflective surface that reflects the infrared light reflected by the light reflecting means toward the light source.

According to one embodiment of the present invention, the reflector member is configured in a hollow truncated cone shape having an opening for taking in the infrared light reflected by the light reflecting means and an inner mirror surface as a reflective surface for reflecting the infrared light taken in from the opening toward the light source, and it is preferable that the opening width in the direction corresponding to the annular shape is longer than the opening width in other directions.

According to the present invention, loosened parts of the dicing tape can be efficiently heated and reliably tensioned.

FIG. 1 is a cross-sectional view showing a main part of a first embodiment of a workpiece dividing device according to the present invention; FIG. 2 is an enlarged view of the main part including the light irradiation member shown in FIG. 1 and its vicinity; FIG. 2 is an explanatory diagram showing a schematic configuration of the light irradiation member shown in FIG. A flowchart showing the operation of the work division device shown in FIG. FIG. 2 is a cross-sectional view showing a state in which the work division device shown in FIG. 1 is performing an expanding operation. Cross-sectional view showing the wafer cover lowered Cross-sectional view showing the state where the dicing tape is lowered A cross-sectional view showing the state in which the loosened portion is being heated by a heating device. FIG. 13 is a perspective view of a main part of a workpiece dividing device according to a second embodiment; 10 is a cross-sectional view taken along the longitudinal axis of the light reflecting member shown in FIG. 10 is a cross-sectional view taken along the short axis of the light reflecting member shown in FIG. FIG. 10 is a perspective view showing a configuration of a reflector member shown in FIG.

Below, an embodiment of the workpiece dividing device according to the present invention will be described with reference to the attached drawings. Note that in this specification, the same components are given the same reference numerals, and duplicated descriptions will be omitted as appropriate.

<Workpiece dividing device of the first embodiment>
FIG. 1 is a cross-sectional view of a main part of a workpiece dividing device 1 according to a first embodiment.

As shown in FIG. 1, the workpiece dividing device 1 of the first embodiment includes a freezing chuck table 10, a push-up ring 12, a ring lifting mechanism 14, a frame fixing mechanism 16, a wafer cover 18, a cover lifting mechanism 20, a light irradiation member 22, a heater lifting mechanism 24, and a light reflecting member 26.

As shown in FIG. 1, a workpiece 2 on which a semiconductor wafer W to be divided is mounted is placed on the upper surface of the frozen chuck table 10.

The workpiece 2 is constructed by mounting the semiconductor wafer W on the frame F via the dicing tape S. The semiconductor wafer W has a grid-like dividing line formed in advance inside it by laser irradiation or the like, and the underside of the semiconductor wafer W is attached to the dicing tape S via a DAF (Die Attach Film) D (hereinafter referred to as DAF (D)). Here, the thickness of the semiconductor wafer W is, for example, about 50 μm, and the thicknesses of the DAF (D) and the dicing tape S are each about several μm to 100 μm. In addition, the substrate of the semiconductor wafer W can be made of silicone, and the dicing tape S and the DAF (D) can be made of PO (Poly Olefine) or PVC (Polyvinyl Chloride). In addition, the dicing tape S in this example has a high infrared light transmittance.

The frozen chuck table 10 vacuum-adsorbs the lower surface of the wafer W through the dicing tape S and the DAF (D). The frozen chuck table 10 also cools the DAF (D) by heat transfer through the dicing tape S. The cooling temperature is preferably 0°C or lower, for example, about -5°C to -10°C. As a result, the DAF (D), which has high viscosity at room temperature, becomes brittle at low temperatures. By making the DAF (D) brittle in this way, the divisibility of the DAF (D) is improved, so that when the dicing tape S is expanded, the semiconductor wafer W is divided and the DAF (D) is simultaneously divided (see FIG. 5). The method of freezing the frozen chuck table 10 may be a method of supplying a refrigerant to the inside of the frozen chuck table 10 to cool the entire frozen chuck table 10, or a method of cooling only the upper surface of the frozen chuck table 10 by utilizing the Peltier effect.

The push-up ring 12 is arranged to surround the freezing chuck table 10, and is raised and lowered by a ring lifting mechanism 14. A plurality of rollers 28 are provided at a predetermined interval on the upper portion of the push-up ring 12 to reduce the frictional force between the push-up ring 12 and the dicing tape S. This push-up ring 12 functions as an expanding means. In FIG. 1, the push-up ring 12 is positioned in a lowered position (standby position), and is raised by the ring lifting mechanism 14 when expanding the dicing tape S (see FIG. 5).

The frame fixing mechanism 16 has the function of fixing the outer periphery of the frame F of the workpiece 2. When the frame F is fixed to the frame fixing mechanism 16, the workpiece W is positioned so that the lower surface of the dicing tape S contacts the upper surface of the frozen chuck table 10.

The wafer cover 18 has a low cylindrical shape with a bottom, and is made up of a bottom plate 18a and a side plate 18b, with the bottom plate 18a having a diameter larger than that of the semiconductor wafer W. The wafer cover 18 is raised and lowered by a cover lifting mechanism 20, and is configured to cover the semiconductor wafer W in the lowered position (see FIG. 6). The lower end surface 18c of the side plate 18b is butted against the upper end surface 12a of the raised push-up ring 12 via the DAF (D), dicing tape S, and roller 28 (see FIG. 6).

Next, we will explain the light irradiation member 22.

1, the light irradiation members 22 are arranged at symmetrical positions in the diametric direction of the work 2 outside the wafer cover 18, and are raised and lowered by the heater lifting mechanism 24. As will be described in detail later, the light irradiation members 22 are configured to selectively heat the peripheral portion of the dicing tape S, i.e., the portion E that has loosened due to expansion, when in the lowered position (see FIG. 7). This light irradiation member 22 functions as a light irradiation means constituting a heating means. In FIG. 1, two light irradiation members 22 are arranged at symmetrical positions in the diametric direction of the work 2, but the number of light irradiation members 22 is not limited to two. For example, four light irradiation members 22 may be arranged at 90 degree intervals around the work 2, or eight light irradiation members 22 may be arranged at 45 degree intervals, or more. The light irradiation members 22 may also have a ring-shaped shape along the peripheral portion of the dicing tape S.

Figure 2 is an enlarged view of the main parts including the light irradiation member 22 and its vicinity, and Figure 3 is an explanatory diagram showing the schematic configuration of the light irradiation member 22 and the light reflection member 26 described later.

In FIG. 2, the dicing tape S including the expanded loose portion E is shown, with the light irradiation member 22 disposed above the loose portion E. Also, the light reflection member 26 is disposed below the loose portion E, with the light irradiation member 22 and the light reflection member 26 disposed opposite each other with the loose portion E in between. Note that the loose portion E refers to the ring-shaped peripheral portion of the dicing tape S located between the outer periphery of the semiconductor wafer W and the inner periphery of the frame F.

3, the light irradiation member 22 has a light source 30 that emits infrared light and an optical member 32 that focuses the infrared light emitted from the light source 30 at a focusing point P. The optical member 32 has the light source 30 attached at its focal position f1 and an ellipsoidal mirror 34 that focuses the infrared light from the light source 30 at the focusing point P. The position of the focusing point P in this example is set at a position about 2 to 3 mm above the upper surface (the surface on the semiconductor wafer W side) of the dicing tape S before expansion where no loosened portion E occurs, as shown by the two-dot chain line in FIG. 2. In addition, the optical member 32 may be a parabolic mirror attached to the light source 30 at its focal position f1 and a focusing lens that focuses the infrared light collimated by the parabolic mirror at the focusing point P.

As described above, in the workpiece dividing device 1 of the first embodiment, a spot-type light irradiation member 22 that focuses infrared light at a focal point P is used as a heating means for heating the loosened portion E. By using such a spot-type light irradiation member 22, it is possible to selectively (locally) heat only the portion of the loosened portion E that is to be heated, and it is possible to minimize the thermal stress on the other portions.

Here, if the loosened portion E is heated using only the light irradiation member 22, the following problems arise:

That is, when a dicing tape S with high infrared light transmittance is used as in this example, the heat from the infrared light from the light irradiation member 22 cannot be sufficiently transmitted to the loosened portion E, and therefore the loosened portion E may not be heated efficiently. Also, in the above case, as the loosened portion E moves away from the focal point P of the light irradiation member 22, it becomes more difficult for the heat from the light irradiation member 22 to be transmitted to the loosened portion E, and therefore it may become difficult to heat the loosened portion E. In this way, when only the light irradiation member 22 is used, the loosened portion E may not be heated efficiently, and therefore the loosened portion may not be reliably tensioned.

In order to solve the above problem, the workpiece dividing device 1 of the first embodiment shown in FIG. 1 is provided with a light reflecting member 26 as a heating means in addition to the light irradiating member 22. This light reflecting member 26 functions as a light reflecting means constituting the heating means.

As shown in FIG. 2, the light irradiation member 22 and the light reflection member 26 are arranged vertically facing each other with the loosened portion E in between, and the light irradiation member 22 emits infrared light toward the loosened portion E as described above. The light reflection member 26 has the following functions to reflect the infrared light that has passed through the loosened portion E toward the loosened portion E.

That is, as shown in FIG. 3, the light reflecting member 26 includes a concave mirror 38 having the above-mentioned function, and the concave mirror 38 reflects the above-mentioned infrared light toward the slackened portion E. As shown in FIG. 2 and FIG. 3, in a preferred embodiment, the focal position f2 of the concave mirror 38 is set to the light-converging point P. Note that the light reflecting member 26 employed in the first embodiment will be described as being entirely composed of the concave mirror 38.

In the workpiece dividing device 1 configured as described above, the loosened portion E can be heated from above by the infrared light from the light irradiation member 22. The infrared light that passes through the loosened portion E is reflected by the light reflecting member 26 toward the loosened portion E, so that the reflected infrared light (hereinafter referred to as "return infrared light") can reheat the loosened portion E from below.

In particular, in the above-mentioned workpiece dividing device 1, the light reflecting member 26 is composed of a concave mirror 38 having a focal position f2 at the focusing point P of the light irradiating member 22, so that the returning infrared light reflected by the concave mirror 38 is returned to the light source 30 via the ellipsoidal mirror 34 shown in FIG. 3, and then emitted again toward the loosened portion E via the ellipsoidal mirror 34 together with the infrared light irradiated from the light source 30. This makes it possible for the infrared light emitted from the light source 30 to travel back and forth between the concave mirror 38 and the light source 30, sandwiching the loosened portion E between them. Therefore, it becomes possible to efficiently heat the loosened portion E without diffusing the returning infrared light.

The flowchart shown in Figure 4 will be explained below with reference to the operation diagrams of the work division device 1 shown in Figures 5 to 8.

First, in step S100 of FIG. 4, the frame F of the workpiece 2 is fixed to the frame fixing mechanism 16 (see FIG. 1). Then, the workpiece 2 is placed so that the area in which the semiconductor wafer W is present is located on the upper surface of the frozen chuck table 10. Note that the semiconductor wafer W has been previously formed with a grid-like pattern of dividing lines formed therein by laser irradiation or the like.

Next, in step S110 of FIG. 4, the dicing tape S is vacuum-adsorbed by the frozen chuck table 10, so that it is securely in contact with the top surface of the frozen chuck table 10. At this time, the frozen chuck table 10 is in a low-temperature state, so this contact cools the workpiece 2 through heat transfer. For example, the DAF (D) is cooled to about -5°C to -10°C, which makes the DAF (D) brittle and makes it easy to break when an external force is applied. The frozen chuck table 10 performs vacuum adsorption for a predetermined time, cooling the workpiece 2 until the DAF (D) reaches the above-mentioned predetermined temperature. The frozen chuck table 10 then releases the vacuum adsorption.

Next, in step S120 of FIG. 4, the push-up ring 12 is raised by the ring lifting mechanism 14 to expand the dicing tape S, as shown in FIG. 5.

As a result, the dicing tape S expands radially from the center of the workpiece 2, and the semiconductor wafer W is divided into each chip T along the intended cutting line together with the DAF (D).

Next, in step S130 of FIG. 4, as shown in FIG. 6, the wafer cover 18 and the light irradiation member 22 are lowered by the cover lifting mechanism 20 and the heater lifting mechanism 24, respectively, and the semiconductor wafer W of the workpiece 2 is covered with the wafer cover 18. At this time, as shown in FIG. 6, the lower end surface 18c of the side plate 18b of the wafer cover 18 and the upper end surface 12a of the push-up ring 12 are butted against each other via the dicing tape S, so that the dicing tape S is gripped between the wafer cover 18 and the push-up ring 12.

Next, in step S140 of FIG. 4, as shown in FIG. 7, while the dicing tape S is being held between the wafer cover 18 and the push-up ring 12, the wafer cover 18 and the push-up ring 12 are lowered to a position where the bottom surface of the dicing tape S contacts the top surface of the frozen chuck table 10. This causes the ring-shaped peripheral portion of the dicing tape S located between the outer periphery of the semiconductor wafer W and the inner periphery of the frame F to relax, creating a slackened portion E in the peripheral portion.

If the workpiece 2 is transported while the loosened portion E remains loose, the individual chips T on the dicing tape S may come into contact with each other or may be subjected to excessive bending stress. For this reason, a process of heating and tensioning the loosened portion E is required, as described below.

As shown in FIG. 7, the loosened portion E is loosened downward in a convex shape, that is, it is loosened in a direction moving downward away from the focal point P of the light irradiation member 22. As described above, the dicing tape S used has a high transmittance for infrared light. In other words, the state of the loosened portion E shown in FIG. 7 is one of the states that is difficult to efficiently heat using only the light irradiation member 22.

Therefore, in the workpiece dividing device 1 of the first embodiment, in step S150 of FIG. 4, infrared light is emitted from the light irradiation member 22 to the loosened portion E, as shown in FIG. 8.

In this way, the loosened portion E is first heated from above by the infrared light from the light irradiation member 22. The loosened portion E is then heated again from below by the returning infrared light that passes through the loosened portion E and is reflected by the light reflecting member 26 (see FIG. 3). In other words, the loosened portion E is heated not only by the infrared light from the light irradiation member 22, but also by the returning infrared light from the light reflecting member 26. As a result, even if the loosened portion E is difficult to heat in the above manner, it is efficiently heated. The loosened portion E gradually becomes taut as it is heated as described above. This completes the process of tautening the loosened portion E.

Next, in step S160 of FIG. 4, the wafer cover 18 and the light irradiation member 22 are raised by the cover lifting mechanism 20 and the heater lifting mechanism 24, respectively, and the push-up ring 12 is lowered by the ring lifting mechanism 14 to release the grip of the dicing tape S. This completes the operation of the workpiece dividing device 1 of the first embodiment.

According to the first embodiment of the workpiece dividing device 1, the light irradiating member 22 that irradiates infrared light toward the loosened portion E and the light reflecting member 26 that reflects the infrared light that has passed through the loosened portion E toward the loosened portion E are arranged opposite each other with the loosened portion E in between, so that the loosened portion E of the dicing tape S can be efficiently heated and reliably tensioned.

In particular, in the workpiece dividing device 1 of the first embodiment, the light reflecting member 26 is configured with a concave mirror 38, so that the returning infrared light can be reflected to the loosened portion E without being diffused. This allows the loosened portion E to be heated efficiently in a short time.

Furthermore, since the focal position f2 of the concave mirror 38 is set at the focal point P of the light irradiation member 22, the returning infrared light reflected by the concave mirror 38 is returned to the light source 30 via the ellipsoidal mirror 34 shown in FIG. 3, and then is emitted again toward the loosened portion E via the ellipsoidal mirror 34 together with the infrared light emitted from the light source 30. This allows the infrared light emitted from the light source 30 to travel back and forth between the concave mirror 38 and the light source 30, sandwiching the loosened portion E between them, making it possible to heat the loosened portion E more efficiently without diffusing the returning infrared light. By adopting such a configuration, even a low-output light source 30 can be used.

Furthermore, when the loosened portion E is heated by the light irradiation member 22 and the light reflection member 26, it is preferable to rotate the light irradiation member 22 and the light reflection member 26 at a constant speed along the periphery of the wafer cover 18 after the light irradiation member 22 is activated and the heated state stabilizes. This makes it possible to uniformly tension the entire area of the loosened portion E. In this case, it is preferable to provide the workpiece dividing device 1 with an irradiation drive mechanism that rotates the light irradiation member 22 along the periphery of the wafer cover 18 and a reflection drive mechanism that rotates the light reflection member 26 along the periphery of the wafer cover 18, and a speed control unit that controls the moving speed of the light irradiation member 22 and the light reflection member 26 by the irradiation drive mechanism and the reflection drive mechanism.

In the first embodiment of the workpiece dividing device 1, the light reflecting means is exemplified as the light reflecting member 26 formed by the concave mirror 38, but this is not limited thereto, and for example, a light reflecting member formed by a plane mirror may be used. In other words, any light reflecting member that can reflect the infrared light that has passed through the loosened portion E toward the loosened portion E can be used as the light reflecting means. However, from the viewpoint of preventing the diffusion of the returning infrared light and enabling the returning infrared light to be reused, it is preferable to use the light reflecting member 26 formed by the concave mirror 38 as the light reflecting means.

In the first embodiment of the workpiece dividing device 1, as shown in FIG. 2, the focal point P is set at a position about 2 to 3 mm above the top surface of the dicing tape S before expansion, but the position of the focal point P is not limited to the above position and may be near the loosened portion E. It is preferable to determine the extent to which the dicing tape S loosens due to expansion through experimentation, for example, and specify the range of the focal point P in which efficient heating is possible based on the relationship between the degree of elimination (degree of tension) of the loosened portion E of the dicing tape S and the position of the focal point P, and set the focal point P within this range.

<Workpiece dividing device according to the second embodiment>
9 is a perspective view of a main part of a work division device 50 of the second embodiment. In describing the work division device 50, the same or similar members as those of the work division device 1 of the first embodiment shown in FIGS. 1 to 8 are denoted by the same reference numerals.

The difference between the configuration of the work division device 50 of the second embodiment and the work division device 1 of the first embodiment is that the light reflecting member 52 of the work division device 50 is configured in a semicircular tube shape, and that the light irradiation member 22 of the work division device 50 is provided with a reflector member 54. The rest of the configuration is the same, so the description will be omitted here as appropriate.

First, the light reflecting member 52 is described. The light reflecting member 52 is configured in a semicircular tube shape formed in correspondence with the annular shape along the outer periphery of the semiconductor wafer W. That is, the light reflecting member 52 is formed along the axis J of the annular shape shown by the dashed line in the figure (hereinafter also referred to as the "annular axis"). Here, in FIG. 9, the direction connecting the center Q of the annular axis J and the intersection R of the annular axis J and the optical axis L of the light irradiation member 22 is called the width direction K of the light reflecting member 52. In this case, the cross-sectional shape of the light reflecting member 52 along the width direction K is formed in an arc shape having a center of curvature C (see FIG. 12) at the light focusing point P of the light irradiation member 22. Note that FIG. 9 shows an example of an arrangement in which multiple light reflecting members 52 are arranged at intervals along the annular axis J. Also, in FIG. 9, only one light irradiation member 22 is shown, but multiple light irradiation members 22 are arranged in correspondence with each light reflecting member 52.

Here, FIG. 10 is a cross-sectional view of the light reflecting member 52 along the circular axis J in FIG. 9, and is a cross-sectional view along imaginary plane A shown by the dashed line in FIG. 9. Also, FIG. 11 is a cross-sectional view of the light reflecting member 52 along the width direction K, and is a cross-sectional view along imaginary plane B shown by the dashed line in FIG. 9. Note that imaginary planes A and B are planes that each include the optical axis L of the light irradiation member 22. Also, in FIG. 10 and FIG. 11, the configuration of the light irradiation member 22 is shown typically.

As shown in FIG. 10, among the infrared light irradiated from the light irradiation member 22, the infrared light component of the component in the direction along the circular axis J (hereinafter referred to as "first infrared light") is condensed from the light irradiation member 22 to the condensing point P. Then, the first infrared light incident on the light reflection member 52 is reflected by the light reflection member 52. At that time, the first infrared light is diffused in various directions as return infrared light depending on the incident angle at which it is incident on the light reflection member 52. On the other hand, as shown in FIG. 11, among the infrared light irradiated from the light irradiation member 22, the infrared light component of the component in the direction along the width direction K (hereinafter referred to as "second infrared light") is condensed from the light irradiation member 22 to the condensing point P. Then, the second infrared light incident on the light reflection member 52 is reflected by the light reflection member 52. At that time, the second infrared light is condensed at the condensing point P as return infrared light depending on the incident angle at which it is incident on the light reflection member 52.

As described above, the returning infrared light of the second infrared light shown in FIG. 11 is focused at the focusing point P and can be reused. In contrast, most of the returning infrared light of the first infrared light shown in FIG. 10 is returning infrared light (hereinafter referred to as "diverged returning infrared light D") that deviates from the returning infrared light G (returning infrared light reflected from the light reflecting member 52 located on the optical axis L) that is directed toward the focusing point P, and therefore cannot be reused.

Therefore, in the workpiece dividing device 50 of the second embodiment, a reflector member 54 is provided on the light irradiating member 22 in order to reuse the above-mentioned "lost and returned infrared light D." An example of the reflector member 54 is described below.

Figure 12 is a perspective view showing the overall configuration of the reflector member 54.

This reflector member 54 has the function of reflecting the "returned infrared light D" caused by the first infrared light toward the light source 30 shown in FIG. 10.

Specifically, as shown in FIG. 12, the reflector member 54 is configured in a hollow truncated cone shape having an outer peripheral surface 60, an inner peripheral surface 62, an elliptical opening 64 formed at one end, and a circular opening 66 formed at the other end.

In addition, in the workpiece dividing device 50 of the second embodiment, the reflector member 54 is positioned as follows, making it possible to effectively capture the "returned infrared light D."

That is, the long axis 64A of the elliptical opening 64 shown in FIG. 12 is arranged along the circular axis J shown in FIG. 9, and the short axis 64B of the opening 64 is arranged along the width direction K.

The reflector member 54 is fixed to the light irradiation member 22 by attaching the end on the opening 66 side to the light irradiation member 22, and the elliptical opening 64 is disposed opposite the light reflection member 52 as shown in FIG. 9. This opening 64 functions as an opening that takes in the return infrared light reflected by the light reflection member 52 into the reflector member 54. The inner peripheral surface 62 of the reflector member 54 is formed as an inner peripheral mirror surface by applying a reflective coating to make the inner peripheral surface 62 function as a reflective surface. As shown in FIG. 10, the inner peripheral surface 62 includes a reflective surface that reflects the above-mentioned "return infrared light D" of the return infrared light taken in from the opening 64 toward the light source 30. As a result, the "return infrared light D" is returned to the light source 30 and then emitted again via the elliptical mirror 34 together with the infrared light irradiated from the light source 30. The above-mentioned reflective surface refers to a reflective surface that directly reflects the "returned infrared light D" toward the light source 30, or a reflective surface that reflects the "returned infrared light D" toward the light source 30 via the ellipsoidal mirror 34.

Therefore, according to the workpiece dividing device 50 of the second embodiment, the above-mentioned reflector member 54 is provided on the light irradiating member 22, so that the "lost and returned infrared light D" can be reused. Therefore, even if the workpiece dividing device 50 employs the semicircular tubular light reflecting member 52 that generates the "lost and returned infrared light D" as the light reflecting means, it is possible to efficiently heat the loosened portion E, as with the workpiece dividing device 1 of the first embodiment.

In particular, according to the second embodiment of the workpiece dividing device 50, the long axis 64A of the opening 64 of the reflector member 54 is arranged along the annular axis J, so that the "lost return infrared light D" shown in FIG. 10 can be taken in over a wide area through the opening 64. This makes it possible to effectively take in the above-mentioned "lost return infrared light D," so that the loosened portion E can be heated even more efficiently.

On the other hand, in the workpiece dividing device 50 of the second embodiment, as shown in FIG. 9, a light reflecting member 52 is disposed in close proximity to the roller 28.

Specifically, of the pair of edges of the light reflecting member 52 parallel to the circular axis J, the edge 52C located on the roller 28 side is brought close to the horizontal side of the roller 28. The position of the roller 28 at this time is the position shown in Figure 8 where the loosened portion E is heated.

In the position shown in FIG. 8, for example, if the light reflecting member 52 is positioned away from the roller 28, or if the light reflecting member 52 is not present, the slack portion E that has loosened downward may wrap around the roller 28, in which case the slack portion E will slacken further downward. As a result, the slack portion E will be further away from the focal point P downward, which may affect the heating of the slack portion E.

Therefore, in the second embodiment of the workpiece dividing device 50, the edge 52C of the light reflecting member 52 is disposed close to the roller 28 on the horizontal side of the roller 28, so that the loose portion E comes into contact with the edge 52C before wrapping around the roller 28. This makes it possible to prevent the loose portion E from wrapping around the roller 28. Also, for example, as shown in FIG. 7, even if the loose portion E wraps around the roller 28 while the push-up ring 12 is being lowered, the loose portion E that has wrapped around the roller 28 is peeled off from the roller 28 by the edge 52C at the position shown in FIG. 8 where the push-up ring 12 has been lowered. In this case as well, it is possible to prevent the loose portion E from wrapping around the roller 28.

Therefore, according to the second embodiment of the workpiece dividing device 50, a configuration is adopted in which the edge 52C of the light reflecting member 52 is disposed close to the roller 28 on the horizontal side of the roller 28, so that the slackened portion E can be prevented from slackening downward, and the slackened portion E can be heated efficiently. Here, with regard to the position of the edge 52C, for example, the extent to which the dicing tape S slackens due to expansion is experimentally determined, and the range of the edge 52C is determined to be capable of effectively preventing the slackened portion E from slackening downward from the relationship between the position of the slackened portion E of the dicing tape S and the edge 52C of the light reflecting member 52, and the edge 52C is set within this range.

In the second embodiment of the workpiece dividing device 50, the reflector member 54 is exemplified as being configured in a truncated cone shape, but the reflector member 54 is not limited to this, and any reflector member including a reflective surface capable of reflecting the above-mentioned "returned infrared light D" toward the light source 30 can be used. In addition, in the above-mentioned reflector member 54, an elliptical shape is exemplified as the shape of the opening 64, but this is not limited. This opening 64 may be an opening whose opening width along the circular axis J is longer than the opening width along other directions (e.g., the width direction K), and may be, for example, an ellipse or a rectangle.

In addition, in the second embodiment of the workpiece dividing device 50, an example of the arrangement of the light reflecting members 52 is shown in which multiple light reflecting members 52 are arranged at intervals along the outer periphery of the semiconductor wafer W, but the arrangement is not limited to this. For example, the light reflecting member 52 as described above may be configured in a ring shape along the entire outer periphery of the semiconductor wafer W.

In addition, the workpiece dividing device 1, 50 described in the first and second embodiments utilizes the infrared light irradiated from the light irradiating member 22 and transmitted through the loosened portion E to reheat the loosened portion E by the light reflecting member 26, 52, making it possible to suppress the temperature rise of the workpiece dividing device 1, 50 caused by the infrared light transmitted through the loosened portion E.

When a halogen lamp is used as the light source 30, the halogen lamp emits light in a wide band from ultraviolet to infrared, including visible light. In this case, the light that contributes to heating the slack portion E is not limited to infrared light alone, and light in other bands also contributes to heating together with the infrared light.

Although an embodiment of the present invention has been described above, the present invention is not limited to the embodiment, and various modifications are possible without departing from the spirit of the invention.

1...workpiece dividing device, 2...workpiece, 10...freezing chuck table, 12...push-up ring, 14...ring lifting mechanism, 16...frame fixing mechanism, 18...wafer cover, 20...cover lifting mechanism, 22...light irradiating member, 24...heater lifting mechanism, 26...light reflecting member, 28...roller, 30...light source, 32...optical member, 34...ellipsoidal mirror, 38...concave mirror, 50...workpiece dividing device, 52...light reflecting member, 54...reflector member, 60...outer peripheral surface, 62...inner peripheral surface, 64...opening, 66...opening

Claims (5)

A workpiece dividing device that expands a dicing tape and divides a workpiece attached to the dicing tape into individual chips,
an expanding means for expanding the dicing tape;
a heating means for heating the portion of the dicing tape that has been loosened by the expanding,
The heating means is
a light irradiation means for irradiating infrared light only onto the loosened portion;
a light reflecting means disposed opposite the light irradiating means with the dicing tape interposed therebetween, the light reflecting means reflecting at least a portion of the infrared light transmitted through the loosened portion only to the loosened portion;
A workpiece dividing device having the above structure. The light irradiation means is
A light source that emits the infrared light;
an optical member that selectively irradiates the infrared light emitted from the light source only onto the loosened portion,
The light reflecting means includes a concave mirror.
The workpiece dividing device according to claim 1 . The light irradiation means focuses the infrared light at a focusing point spaced apart from the dicing tape,
the light reflecting means reflects at least a portion of the infrared light that has passed through the loosened portion so that the infrared light is focused at the focusing point;
The workpiece dividing device according to claim 1 or 2. The light irradiation means is
A light source that emits the infrared light;
an optical member that selectively irradiates the infrared light emitted from the light source only onto the loosened portion,
The light reflecting means is configured in a semicircular tube shape formed in correspondence with a circular ring shape along an outer periphery of the workpiece,
The light irradiation means has a reflector member,
the reflector member includes a reflecting surface that reflects a portion of the infrared light that has been reflected by the light reflecting means and transmitted through the loosened portion toward the light source.
The workpiece dividing device according to claim 1 . the reflector member is configured in a hollow truncated cone shape having an opening for taking in a portion of the infrared light reflected by the light reflecting means, and an inner peripheral mirror surface as the reflecting surface for reflecting a portion of the infrared light taken in from the opening toward the light source,
The opening has a width in a direction corresponding to the annular shape that is longer than a width in other directions.
The workpiece dividing device according to claim 4 .

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