JP7844133B2 - Expanding device and expanding method - Google Patents

Description

This invention relates to an expandable apparatus and method for dividing a workpiece by expanding a sheet to which a workpiece, to which a dividing point has been formed, is attached.

An expanding device is used that divides a workpiece by attaching an expandable sheet to the back surface of the workpiece, where the dividing points are formed along a predetermined dividing line, and then expanding the expandable sheet (see, for example, Patent Document 1).

The expanding apparatus described in Patent Document 1 cools the workpiece during expansion to improve its divisibility when the workpiece contains ductile materials such as DAF (die attach film) or metal films.

Japanese Patent Publication No. 2019-186437

On the other hand, the expanded sheet attached to the workpiece also possesses ductility, and this ductility is suppressed by cooling. If only the expanded sheet in the area where the workpiece is attached is cooled, and the expanded sheet in the area outside the workpiece remains uncooled, then the area of the expanded sheet on the outer periphery of the workpiece will expand, while the expanded sheet in the area where the workpiece is attached will not expand sufficiently, resulting in areas where the workpiece remains undivided.

The object of the present invention is to provide an expanding apparatus and method that can reduce the risk of undivided areas occurring in a workpiece.

To solve the above-mentioned problems and achieve the objective, the present invention provides an expandable device for dividing a workpiece by expanding a sheet to which a workpiece is attached, with a dividing starting point formed and the outer edge of the sheet being supported by the sheet attached to the inside of the annular frame, the device comprising: a frame holding unit having a frame holding member on which the annular frame is placed on its upper surface; an expansion mechanism for expanding the sheet; and a cooling unit for cooling the area of the sheet to which the workpiece is not attached to the sheet to a lower temperature than the area of the sheet to which the workpiece is attached, the cooling unit The device is characterized by comprising : a first cooling air ejection hole which is positioned above the workpiece , which is held by the annular frame by the frame holding unit and has an outer diameter equal to the inner diameter of the frame holding member, and is positioned opposite the workpiece at a distance from the workpiece, facing the workpiece which is attached to the sheet, and injecting cooling air at a first temperature lower than room temperature toward the workpiece; and a second cooling air ejection hole which faces the area of the sheet to which the workpiece is not attached, and injects cooling air at a second temperature lower than the first temperature toward the area of the sheet to which the workpiece is not attached.

The present invention provides an expanding device for dividing a workpiece by expanding a sheet to which a workpiece is attached and to which a dividing starting point has been formed, and comprises an expansion mechanism for expanding the sheet, and a cooling unit for cooling the area of the sheet to which the workpiece is not attached to the sheet to a lower temperature than the area of the sheet to which the workpiece is attached, wherein the expansion mechanism comprises a sheet clamping unit having a first clamping part and a second clamping part that are opposite to each other and clamp the sheet in a first direction, and a third clamping part and a fourth clamping part that are opposite to each other and clamp the sheet in a second direction perpendicular to the first direction, a first moving unit for moving the first clamping part and the second clamping part in a direction away from each other in the first direction, and a third clamping part and the fourth clamping part in a direction away from each other in the second direction The cooling unit comprises a second moving unit, the cooling unit having a contact surface that contacts the sheet held by the sheet clamping unit and a cooling table for cooling the sheet, the contact surface comprising a first region corresponding to the region to which the workpiece is attached and a second region surrounding the first region and corresponding to the region between the workpiece and the first, second, third, and fourth clamping portions, the cooling table comprising a first Peltier element layer overlapping the first region and a second Peltier element layer overlapping the second region and supplied with power independently of the first Peltier element layer, the first Peltier element layer being supplied with power of a first voltage so that the first region is set to a first temperature, and the second Peltier element layer being supplied with power of a second voltage higher than the first voltage so that the second region is set to a second temperature lower than the first temperature.

The present invention provides an expanding method for dividing a workpiece by expanding a sheet to which a workpiece is attached, with a dividing starting point formed and the outer edge of the sheet being supported by a sheet attached to the annular frame inside the annular frame, the method comprising: a sheet cooling step of cooling the area of the sheet to which the workpiece is not attached to the sheet to a lower temperature than the area of the sheet to which the workpiece is attached; and a dividing step of expanding the sheet to divide the workpiece after performing the sheet cooling step, wherein in the sheet cooling step, the outer diameter is such that the annular frame is placed on the upper surface The cooling unit is positioned above the workpiece, which is held by the annular frame by a disc-shaped member with an inner diameter equivalent to that of the frame holding member, and is spaced apart from the workpiece. The cooling unit is attached to the sheet of the cooling unit and has a first cooling air outlet facing the workpiece from a first cooling air outlet facing the workpiece, while simultaneously spraying a second cooling air outlet facing the area of the sheet where the workpiece is not attached, towards the area of the sheet where the workpiece is not attached.

The present invention provides an expanding method for dividing a workpiece by expanding a sheet to which a workpiece is attached and to which a dividing starting point has been formed, comprising: a sheet cooling step of cooling the area of the sheet to which the workpiece is not attached to the area of the sheet to a lower temperature than the area to which the workpiece is attached; and a dividing step of expanding the sheet after performing the sheet cooling step to divide the workpiece, wherein the sheet cooling step is performed by bringing a cooling table into contact with the sheet, the cooling table having a contact surface consisting of a first region corresponding to the area to which the workpiece is attached, and a second region surrounding the first region and corresponding to the area between the workpiece and the first, second, third, and fourth clamping portions , and the cooling table having a first Peltier element overlapping the first region The device comprises a layer and a second Peltier element layer that overlaps the second region and is supplied with power independently of the first Peltier element layer, wherein the first Peltier element layer is supplied with power of a first voltage so that the first region is set to a first temperature, and the second Peltier element layer is supplied with power of a second voltage higher than the first voltage so that the second region is set to a second temperature lower than the first temperature, and the splitting step is characterized in that the sheet is expanded by moving the first and second clamping parts, which are facing each other and sandwiching the workpiece in a first direction and holding the sheet, in a direction away from each other in the first direction, and by moving the third and fourth clamping parts, which are facing each other and sandwiching the workpiece in a second direction perpendicular to the first direction and holding the sheet, in a direction away from each other in the second direction.

This invention has the effect of reducing the risk of undivided areas occurring in the workpiece.

Figure 1 is a perspective view showing an example of the configuration of an expander according to Embodiment 1. Figure 2 is a perspective view showing an example of a workpiece being divided by the expansion device shown in Figure 1. Figure 3 is a perspective view showing another example of a workpiece being divided by the expanding device shown in Figure 1. Figure 4 is a flowchart showing the flow of the expansion method according to Embodiment 1. Figure 5 is a schematic cross-sectional view showing the sheet cooling step of the expansion method shown in Figure 4. Figure 6 is a schematic cross-sectional view showing the division steps of the expansion method shown in Figure 4. Figure 7 is a perspective view showing an example of the configuration of an expander according to Embodiment 2. Figure 8 is a plan view showing the sheet clamping unit and cooling table of the expander shown in Figure 7. Figure 9 is a cross-sectional view showing the configuration of the cooling table of the expander shown in Figure 7. Figure 10 is a schematic cross-sectional view showing the cooling step of the expansion method according to Embodiment 2. Figure 11 is a schematic cross-sectional view showing the state of the expanded sheet before expansion in the dividing step of the expanding method according to Embodiment 2. Figure 12 is a schematic cross-sectional view showing the expanded sheet in the expanded state during the dividing step of the expanding method according to Embodiment 2. Figure 13 is a schematic cross-sectional view showing the cooling table after the division step of the expansion method according to Embodiment 2. Figure 14 is a cross-sectional view showing the configuration of the cooling table of an expander according to a modified example of Embodiment 2.

The embodiments for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below. Furthermore, the components described below include those that are easily conceivable to those skilled in the art, and those that are substantially the same. Moreover, the components described below can be combined as appropriate. In addition, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the present invention.

[Embodiment 1]
An expanding apparatus and an expanding method according to Embodiment 1 of the present invention will be described with reference to the drawings. Figure 1 is a perspective view showing an example of the configuration of the expanding apparatus according to Embodiment 1. Figure 2 is a perspective view showing an example of a workpiece to be divided by the expanding apparatus shown in Figure 1. Figure 3 is a perspective view showing another example of a workpiece to be divided by the expanding apparatus shown in Figure 1. Figure 4 is a flowchart showing the flow of the expanding method according to Embodiment 1.

The expander 1 shown in Figure 1, according to Embodiment 1, is a device that expands an expandable sheet 201, to which the workpiece 200 shown in Figure 2 is attached, thereby dividing the workpiece 200 into individual chips 202. The workpiece 200 processed by the expander 1 according to Embodiment 1 is a disc-shaped semiconductor wafer or optical device wafer, as shown in Figure 2, with a substrate 203 made of silicon, sapphire, gallium arsenide, or SiC (silicon carbide).

In Embodiment 1, as shown in Figure 2, the workpiece 200 has devices 206 formed in each region demarcated by a plurality of intersecting division lines 205 on the surface 204 of the substrate 203. The devices 206 are, for example, integrated circuits such as ICs (Integrated Circuits) or LSIs (Large Scale Integrations), or image sensors such as CCDs (Charge Coupled Devices) or CMOSs (Complementary Metal Oxide Semiconductors).

The workpiece 200 has a modified layer 207 (shown as a dashed line in Figure 2) formed inside the substrate 203 along the planned division line 205, which serves as the starting point for division. The modified layer 207 refers to a region where the density, refractive index, mechanical strength, and other physical properties differ from those of the surrounding area. Examples include a melted region, a cracked region, a dielectric breakdown region, a refractive index change region, and a region where these regions are mixed. In Embodiment 1, the modified layer 207 has lower mechanical strength than other parts of the substrate 203.

Furthermore, in Embodiment 1, as shown in Figure 2, the workpiece 200 has a DAF (Die Attach Film) 209 attached to the expanded sheet 201 on the back surface 208 side of the substrate 203. An annular frame 210 is mounted on the outer edge of the expanded sheet 201, and the workpiece 200 is supported by the expanded sheet 201 within the opening 211 inside the annular frame 210. With the DAF 209 and expanded sheet 201 attached to the back surface 208 of the substrate 203, the workpiece 200 is divided into individual chips 202 along the modified layer 207 by the expanding device 1, together with the DAF 209.

The chip 202 comprises a portion of the substrate 203 and a device 206 formed on the surface 204 of the substrate 203, with a portion of the DAF 209 attached to the back surface 208. The DAF 209 is used to fix the chips 202, which have been individually separated from the workpiece 200, to the substrate or the like. In Embodiment 1, the DAF 209 is formed in a disc shape with a larger diameter than the workpiece 200 and is attached to the back surface 208 of the substrate 203 and the expanded sheet 201.

The expanded sheet 201 is elastic and, for example, is formed by stretching a heated synthetic resin along a first direction 212 while simultaneously stretching it in a second direction 213 perpendicular to the first direction 212. The expanded sheet 201 comprises a base layer made of an elastic synthetic resin and an adhesive layer laminated to the base layer and made of an elastic and adhesive synthetic resin. In Embodiment 1, the first direction 212 is the so-called flow direction (MD: Machine Direction), and the second direction 213 is the so-called vertical direction (TD: Transverse Direction). Note that the expandable sheet 201 loses its elasticity when cooled, and its stretchability decreases as the temperature decreases.

Furthermore, the workpiece 200 to be processed by the expander 1 shown in Figure 1 may be a wafer in which a metal film 214 is formed on the back surface 208 of a substrate 203, an expanded sheet 201 is attached to the metal film 214, an annular frame 210 is mounted on the outer edge of the expanded sheet 201, and the expanded sheet 201 is supported within an opening 211 inside the annular frame 210, as shown in Figure 3. In the workpiece 200 shown in Figure 3, with the expanded sheet 201 attached to the metal film 214 on the back surface 208 of the substrate 203, the substrate 203 and the metal film 214 are divided into individual chips 202 along the modified layer 207 by the expander 1. In the case of the workpiece 200 shown in Figure 3, the chip 202 comprises a part of the substrate 203, a device 206 formed on the surface 204 of the substrate 203, and a part of the metal film 214 formed on the back surface 208. Figure 3 uses the same reference numerals as Figure 2, and its explanation is omitted.

The workpiece 200 shown in Figure 2 is more difficult to separate into individual chips 202 than a workpiece 200 in which a modified layer 207 is formed along the planned division line 205 and a DAF 209 is not attached to the back surface 208. Similarly, the workpiece 200 shown in Figure 3 is more difficult to separate into individual chips 202 than a workpiece 200 in which a modified layer 207 is formed along the planned division line 205 and a metal film 214 is not attached to the back surface 208. Thus, in this invention, it is desirable that the workpiece 200 is a wafer that is difficult to separate into chips 202, either by having a DAF 209 attached to the back surface 208 as shown in Figure 2, or by having a metal film 214 formed on the back surface 208 as shown in Figure 3.

In Embodiment 1, the workpiece 200 has a modified layer 207 formed as the dividing point. However, in the present invention, the workpiece 200 is not limited to a modified layer 207. For example, the dividing point may be a cutting groove formed by cutting with a cutting blade from the surface 204 side, or a laser-processed groove formed by irradiating the workpiece 200 with a laser beam of a wavelength that is absorbed by the workpiece 200 from the surface 204 side.

The expander 1 according to Embodiment 1 is a device that expands an expanded sheet 201 to which a workpiece 200 with a modified layer 207 formed on it is attached, thereby dividing the workpiece 200 into individual chips 202, and also dividing the DAF 209 for each individual chip 202. As shown in Figure 1, the expander 1 according to Embodiment 1 comprises an expansion unit 10, which is an expansion mechanism, a cooling unit 20, and a control unit 30.

The expansion unit 10 extends the expanded sheet 201. The expansion unit 10 comprises a disc-shaped base 11, a frame holding unit 12, an expansion drum 13, and a lifting unit 14.

The frame holding unit 12 holds the annular frame 210. The frame holding unit 12 has an annular frame holding member 15 mounted on the base 11, and a plurality of clamps 16 arranged on the outer edge of the frame holding member 15. The inner diameter of the frame holding member 15 is smaller than the inner diameter of the annular frame 210 and larger than the outer diameter of the workpiece 200. The outer diameter of the frame holding member 15 is equal to the outer diameter of the annular frame 210. The upper surface of the frame holding member 15 is a mounting surface 17 on which the annular frame 210 is placed. The mounting surface 17 is flat along the horizontal direction. The clamps 16 clamp the annular frame 210 placed on the mounting surface 17, fixing the annular frame 210 to the frame holding member 15. In Embodiment 1, four clamps 16 are arranged at equal intervals in the circumferential direction.

The expansion drum 13 is mounted on the base 11 and is cylindrical in shape. The expansion drum 13 is positioned inside the frame holding member 15 and coaxially with the frame holding member 15. The inner and outer diameters of the expansion drum 13 are smaller than the inner diameters of the annular frame 210 and the frame holding member 15, and larger than the outer diameter of the workpiece 200.

The lifting unit 14 moves the frame holding unit 12 and the expansion drum 13 relative to each other along the vertical direction. In Embodiment 1, the lifting unit 14 raises and lowers the frame holding unit 12 between a position where the mounting surface 17 is on the same plane as the upper end of the expansion drum 13 and a position where the mounting surface 17 is below the upper end of the expansion drum 13. In Embodiment 1, the lifting unit 14 is an air cylinder comprising a cylinder 18 attached to the base 11 and a piston rod 19 that is extendable and retractable from the cylinder 18 and has a frame holding member 15 attached to its upper end. In Embodiment 1, multiple lifting units 14 are provided at intervals in the circumferential direction of the base 11.

The cooling unit 20 cools the expanded sheet 201 such that the region 215 (shown in Figures 2 and 3), which is the area between the inner edge of the annular frame 210 and the outer edge of the workpiece 200 to which the workpiece 200 is not attached, is cooler than the region 216 (shown in Figures 2 and 3), which is the area inside the outer edge of the workpiece 200 to which the workpiece 200 is attached. In Embodiment 1, the cooling unit 20 is formed in a disc shape with an outer diameter equal to the inner diameter of the frame holding member 15. In Embodiment 1, the cooling unit 20 is positioned above the expansion drum 13 and the frame holding member 15, and coaxially with the expansion drum 13 and the frame holding member 15.

The cooling unit 20 includes a first cooling air outlet 21 facing vertically in a region 216 of the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12, that is, in a region inside the outer edge of the workpiece 200, i.e., facing vertically in a region 215 of the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12, between the inner edge of the annular frame 210 and the outer edge of the workpiece 200, and a second cooling air outlet 22 facing vertically in a region 215 of the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12. Multiple first cooling air outlets 21 and multiple second cooling air outlets 22 are provided.

The first cooling air outlet 21 injects cooling air 23 (indicated by an arrow in Figure 5) at a first temperature lower than room temperature (for example, -5°C in Embodiment 1) toward the region 216 inside the outer edge of the workpiece 200 on the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12, i.e., toward the workpiece 200 attached to the expanded sheet 201. The first cooling air outlet 21 cools the region 216 inside the outer edge of the workpiece 200 on the expanded sheet 201 to the first temperature via the workpiece 200.

The second cooling air outlet 22 injects cooling air 24 (indicated by an arrow in Figure 5) at a second temperature lower than room temperature and the first temperature (for example, -10°C in Embodiment 1) toward the region 215 between the inner edge of the annular frame 210 and the outer edge of the workpiece 200, where the expanded sheet 201 is attached to the annular frame 210 held by the frame holding unit 12. The second cooling air outlet 22 cools the region 215 between the inner edge of the annular frame 210 and the outer edge of the workpiece 200 to the second temperature.

The control unit 30 controls each component of the expander 1, causing the expander 1 to perform the expansion operation to expand the expander sheet 201. The control unit 30 is a computer comprising a arithmetic processing unit (AMS) with a microprocessor such as a CPU, a storage device with memory such as ROM (read-only memory) or RAM (random access memory), and an input/output interface device. The AMS of the control unit 30 performs calculations according to the computer program stored in the storage device and outputs control signals for controlling the expander 1 to each component of the expander 1 via the input/output interface device.

Furthermore, the control unit 30 is connected to a display unit (not shown) which consists of a liquid crystal display device that displays the status of machining operations and images, and an input unit (not shown) used by the operator to register machining content information. The input unit consists of at least one of the following: a touch panel provided on the display unit and an external input device such as a keyboard.

Next, the expansion method according to Embodiment 1 will be described. The expansion method according to Embodiment 1 is a method of expanding an expanded sheet 201 to which a workpiece 200 with a modified layer 207 formed on it is attached, thereby dividing the workpiece 200 into individual chips 202. The expansion method according to Embodiment 1 is carried out by a control unit 30 controlling each component of the expansion device 1, and as shown in Figure 4, it comprises a holding step 1001, a sheet cooling step 1002, and a dividing step 1003.

(Holding step)
The holding step 1001 is a step in which the frame holding unit 12 of the expanding device 1 holds the outer edge of the expanded sheet 201 to which the workpiece 200 is attached and the annular frame 210 attached to the outer edge of the expanded sheet 201. In the holding step 1001, the expanding device 1 extends the piston rod 19 of the lifting unit 14 to position the mounting surface 17 of the frame holding member 15 and the upper end of the expansion drum 13 on the same plane.

In the holding step 1001, the expander 1 places the annular frame 210, which is attached to the expandable sheet 201, and the outer edge of the expandable sheet 201 on the mounting surface 17 of the frame holding member 15. In the holding step 1001, the expander 1 clamps the annular frame 210 and the outer edge of the expandable sheet 201, which are attached to the expandable sheet 201, on the mounting surface 17 of the frame holding member 15 using the clamp 16, thereby fixing them to the frame holding member 15. At this time, the upper end of the expansion drum 13 is in contact with the region 215 between the inner edge of the annular frame 210 (which is attached to the expandable sheet 201 held by the frame holding unit 12) and the outer edge of the workpiece 200.

(Seat cooling step)
Figure 5 is a schematic cross-sectional view showing the sheet cooling step of the expansion method shown in Figure 4. The sheet cooling step 1002 is a step of cooling the region 215 between the inner edge of the annular frame 210 of the expanded sheet 201 and the outer edge of the workpiece 200 so that it is colder than the region 216 inside the outer edge of the workpiece 200 of the expanded sheet 201.

In Embodiment 1, during the sheet cooling step 1002, as shown in Figure 5, the expanding device 1, with its cooling unit 20, sprays cooling air 23 at a first temperature from the first cooling air outlet 21 for a predetermined time, towards the region 216 inside the outer edge of the workpiece 200 on the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12, i.e., towards the workpiece 200 attached to the expanded sheet 201. In Embodiment 1, during the sheet cooling step 1002, the expanding device 1 cools the region 216 inside the outer edge of the workpiece 200 on the expanded sheet 201, i.e., the workpiece 200, to the first temperature via the workpiece 200.

Furthermore, in Embodiment 1, during the sheet cooling step 1002, as shown in Figure 5, the expanding device 1 simultaneously injects cooling air 23 from the first cooling air ejection hole 21 and, for a predetermined time, injects cooling air 24 at a second temperature from the second cooling air ejection hole 22 towards the region 215 between the inner edge of the annular frame 210 of the expanded sheet 201 attached to the annular frame 210 held by the frame holding unit 12 and the outer edge of the workpiece 200. In Embodiment 1, during the sheet cooling step 1002, the expanding device 1 cools the region 215 between the inner edge of the annular frame 210 of the expanded sheet 201 and the outer edge of the workpiece 200 to a second temperature lower than the first temperature. As a result, because the second temperature is lower than the first temperature, the expanded sheet 201 expands more easily in the region 215 inside the outer edge of the workpiece 200 than in the region 216 between the inner edge of the annular frame 210 and the outer edge of the workpiece 200.

(Division step)
Figure 6 is a schematic cross-sectional view showing the division step of the expansion method shown in Figure 4. The division step 1003 is a step in which, after performing the sheet cooling step 1002, the expanded sheet 201 is expanded to divide the workpiece 200 into individual chips 202. In Embodiment 1, in the division step 1003, the expansion device 1 stops the injection of cooling air 23, 24 from the cooling unit 20, and as shown in Figure 6, retracts the piston rod 19 of the lifting unit 14 to lower the frame holding unit 12, thereby moving the frame holding unit 12 and the expansion drum 13 relative to each other in the vertical direction.

As a result, the expanded sheet 201 expands in the planar direction because the region 215 between the inner edge of the annular frame 210 and the outer edge of the workpiece 200, where the expanded sheet 201 is attached to the annular frame 210 held by the frame holding unit 12, is in contact with the upper end of the expansion drum 13. In the splitting step 1003, as a result of the expansion, radial tensile forces act on the expanded sheet 201.

When a tensile force is applied radially to the expanded sheet 201 attached to the back surface 208 side of the substrate 203 of the workpiece 200 via the DAF 209, the second temperature is lower than the first temperature. Therefore, the region 216 of the expanded sheet 201 inside the outer edge of the workpiece 200 expands beyond the region 215 between the inner edge of the annular frame 210 of the expanded sheet 201 and the outer edge of the workpiece 200. In Embodiment 1, in the splitting step 1003, as shown in Figure 6, the workpiece 200 is split into individual devices 206 using the modified layer 207 as the starting point for fracture, and individual chips 202 are separated. Furthermore, because the workpiece 200 fractures along the modified layer 207, the DAF 209 also fractures along the modified layer 207.

In Embodiment 1, the frame holding unit 12 was lowered in the splitting step 1003 to expand the expanded sheet 201. However, the present invention is not limited to this, and the expansion drum 13 may also be raised. In short, the expansion drum 13 can be raised relative to the frame holding unit 12, and the frame holding unit 12 can be lowered relative to the expansion drum 13. Thus, in Embodiment 1, the expanded sheet 201 is expanded in the splitting step 1003 to divide the workpiece 200 into individual chips 202.

As described above, the expandable sheet 201 according to Embodiment 1 includes a cooling unit 20 that cools the region 216 of the expandable sheet 201 inside the outer edge of the workpiece 200 to a first temperature, and cools the region 215 between the inner edge of the annular frame 210 of the expandable sheet 201 and the outer edge of the workpiece 200 to a second temperature lower than the first temperature. Therefore, the expandable sheet 201 according to Embodiment 1 can cool the region 215 between the inner edge of the annular frame 210 of the expandable sheet 201 and the outer edge of the workpiece 200 to a lower temperature than the region 216 inside the outer edge of the workpiece 200, and can expand the expandable sheet 201 while suppressing the expansion and contraction of the region 215 between the inner edge of the annular frame 210 of the expandable sheet 201 more than the region 216 inside the outer edge of the workpiece 200.

As a result, the expandable device 1 according to Embodiment 1 can sufficiently expand the region 216 inside the outer edge of the workpiece 200 of the expandable sheet 201, thereby reducing the risk of undivided areas occurring in the workpiece 200.

Furthermore, the expansion method according to Embodiment 1 performs a sheet cooling step 1002 in which the region 216 of the expanded sheet 201 inside the outer edge of the workpiece 200 is cooled to a first temperature, and the region 215 between the inner edge of the annular frame 210 of the expanded sheet 201 and the outer edge of the workpiece 200 is cooled to a second temperature lower than the first temperature. This allows for sufficient expansion of the region 216 of the expanded sheet 201 inside the outer edge of the workpiece 200, reducing the risk of undivided areas occurring in the workpiece 200.

[Embodiment 2]
An expanding apparatus and an expanding method according to Embodiment 2 of the present invention will be described based on the drawings. Figure 7 is a perspective view showing an example of the configuration of the expanding apparatus according to Embodiment 2. Figure 8 is a plan view showing the sheet clamping unit and cooling table of the expanding apparatus shown in Figure 7. Figure 9 is a cross-sectional view showing the configuration of the cooling table of the expanding apparatus shown in Figure 7. Figure 10 is a schematic cross-sectional view showing the cooling step of the expanding method according to Embodiment 2. Figure 11 is a schematic cross-sectional view showing the state before the expanded sheet is expanded in the dividing step of the expanding method according to Embodiment 2. Figure 12 is a schematic cross-sectional view showing the expanded sheet in the expanded state after it has been expanded in the dividing step of the expanding method according to Embodiment 2. Figure 13 is a schematic cross-sectional view showing the cooling table after the dividing step of the expanding method according to Embodiment 2. Note that Figures 7 to 13 use the same reference numerals as Embodiment 1 for the same parts and their descriptions are omitted.

The expandable device 1-2 according to Embodiment 2 expands an expandable sheet 201 to which a workpiece 200 is attached in a first direction 212 and a second direction 213, thereby dividing the workpiece 200 into individual chips 202 and also dividing the DAF 209 for each individual chip 202. Furthermore, the expandable device 1-2 expands the expandable sheet 201 to divide the workpiece 200 into individual chips 202, then attaches an annular frame 210 to the expandable sheet 201, and supports the workpiece 200 within the opening 211 of the annular frame 210.

As shown in Figure 7, the expander 1-2 comprises a flat fixed base 31, a cooling unit 40, a workpiece transport unit (not shown), an expansion unit 60 (an expansion mechanism), a frame transport unit (not shown), a sheet cutting unit (not shown), and a control unit 100.

The cooling unit 40 includes a cooling table 41 located in the center of the fixed base 31. As shown in Figure 8, the cooling table 41 has a rectangular (square in Embodiment 2) planar shape, and an expanded sheet 201, clamped by the sheet clamping unit 61 of the expansion unit 60 and to which the DAF 209 is attached, is placed on the contact surface 42, which is the upper surface. That is, the cooling table 41 has a contact surface 42 that contacts the expanded sheet 201 clamped by the sheet clamping unit 61. The cooling table 41 is provided to be movable vertically by a moving mechanism. The contact surface 42 is formed flat along the horizontal direction, and a workpiece 200 can be placed on it via the expanded sheet 201. The workpiece 200 is placed on the contact surface 42 via the expanded sheet 201.

Furthermore, in Embodiment 1, the contact surface 42 of the cooling table 41, as shown in Figures 8 and 9, consists of a first region 43 corresponding to the area on the expanded sheet 201 to which the workpiece 200 held by the sheet clamping unit 61 is attached, and a second region 44 surrounding the first region 43, corresponding to the area between the workpiece 200 on the expanded sheet 201 held by the sheet clamping unit 61 and the first clamping portion 62-1, second clamping portion 62-2, third clamping portion 62-3, and fourth clamping portion 62-4 of the sheet clamping unit 61 of the expansion unit 60.

The first region 43 is the region where the region 217 (shown in Figure 8) to which the workpiece 200 of the expanded sheet 201, held by the sheet clamping unit 61, is attached, overlaps. In Embodiment 1, it is located in the center of the contact surface 42 and has a rectangular shape (a square in Embodiment 1). The region 217 to which the workpiece 200 of the expanded sheet 201, held by the sheet clamping unit 61, is attached corresponds to the region to which the workpiece 200 of the expanded sheet 201 is attached.

The second region 44 is the region where the region 217 to which the workpiece 200 of the expanded sheet 201 held by the sheet clamping unit 61 is attached, and the region 218 (shown in Figure 8) between the first clamping portion 62-1, the second clamping portion 62-2, the third clamping portion 62-3, and the fourth clamping portion 62-4 of the sheet clamping unit 61 overlap. In Embodiment 1, it is provided on the outer edge of the contact surface 42, and the inner and outer edges are formed in a rectangular (square in Embodiment 1) frame shape. The region 218 between the region 217 to which the workpiece 200 of the expanded sheet 201 held by the sheet clamping unit 61 is attached, and the region between the first clamping portion 62-1, the second clamping portion 62-2, the third clamping portion 62-3, and the fourth clamping portion 62-4 of the sheet clamping unit 61, is the region to which the workpiece 200 of the expanded sheet 201 is not attached.

Furthermore, as shown in Figures 9(A) and 9(B), the cooling table 41 comprises a table base 45, a first Peltier element layer 46-1 disposed on the table base 45, a second Peltier element layer 46-2 disposed on the table base 45 and surrounding the outer edge of the first Peltier element layer 46-1, and a cooling plate 47 disposed on the Peltier element layers 46-1 and 46-2. The planar shapes of the table base 45 and the cooling plate 47 are the same as the planar shape of the cooling table 41. The upper surface of the cooling plate 47 is the aforementioned contact surface 42.

The first Peltier element layer 46-1 and the second Peltier element layer 46-2 each contain at least one Peltier element powered by the power supply circuit 48. The first Peltier element layer 46-1 is positioned below the first region 43 of the contact surface 42, and the second Peltier element layer 46-2 is positioned below the second region 44 of the contact surface 42.

Each power supply circuit 48 includes a pair of polarity switching units 49-1 and 49-2. Each polarity switching unit 49-1 and 49-2 includes a DC power supply 50 and a switch 51. When the power supply circuit 48 supplies power from the DC power supply 50 of one polarity switching unit 49-1 to the Peltier element layers 46-1 and 46-2, it cools the contact surfaces 42, i.e., regions 43 and 44, to a temperature lower than room temperature. When the power supply circuit 48 supplies power from the DC power supply 50 of the other polarity switching unit 49-2 to the Peltier element layers 46-1 and 46-2, it heats the contact surfaces 42, i.e., regions 43 and 44, to a temperature higher than room temperature.

One polarity switching unit 49-1 of the power supply circuit 48 that supplies power to the first Peltier element layer 46-1 supplies power at a first voltage to the first Peltier element layer 46-1, cooling the first region 43 to a first temperature. Another polarity switching unit 49-1 of the power supply circuit 48 that supplies power to the second Peltier element layer 46-2 supplies power at a second voltage higher than the first voltage to the second Peltier element layer 46-2, cooling the second region 44 to a second temperature. Thus, the first region 43 of the contact surface 42 of the cooling table 41 is set to a first temperature, and the second region 44 is set to a second temperature lower than the first temperature.

The workpiece transport unit is positioned above the sheet clamping unit 61 and holds the workpiece 200 on its underside. The workpiece transport unit is provided to move vertically by a lifting unit and horizontally by a horizontal movement unit. The horizontal movement unit positions the workpiece transport unit so that the workpiece 200 held on its underside faces the first area 43 of the cooling table 41 vertically. Furthermore, the workpiece transport unit is lowered by the lifting unit, thereby attaching the workpiece 200 to the DAF 209 on the expanded sheet 201 held by the sheet clamping unit 61.

The expansion unit 60 comprises a sheet clamping unit 61 for clamping the expanded sheet 201 and a moving unit 70.

The sheet clamping unit 61 has a first clamping section 62-1, a second clamping section 62-2, a third clamping section 62-3, and a fourth clamping section 62-4. The first clamping section 62-1, the second clamping section 62-2, the third clamping section 62-3, and the fourth clamping section 62-4 clamp the outer periphery of the workpiece 200 attached to the expanded sheet 201.

The first clamping portion 62-1 and the second clamping portion 62-2 face each other, clamping the workpiece 200 in the first direction 212 of the expanded sheet 201. The third clamping portion 62-3 and the fourth clamping portion 62-4 face each other, clamping the workpiece 200 in the second direction 213 of the expanded sheet 201. Since the first clamping portion 62-1, the second clamping portion 62-2, the third clamping portion 62-3, and the fourth clamping portion 62-4 have substantially the same configuration, the same reference numerals are used to describe the same parts.

The first clamping section 62-1, the second clamping section 62-2, the third clamping section 62-3, and the fourth clamping section 62-4 each comprise a columnar movable base 63 mounted on a fixed base 31, a pair of clamping members 64 mounted on the movable base 63 so as to be vertically movable, and a moving mechanism 65 that moves the pair of clamping members 64 toward and toward each other.

The moving mechanism 65 is provided on the moving base 63. The moving mechanism 65 comprises a motor that allows a pair of clamping members 64 to move vertically, a ball screw rotated around its axis by the motor, and a nut that is screwed onto the ball screw and connected to the pair of clamping members 64 via a support arm 66. The moving mechanism 65 moves the nut, support arm 66, and clamping members 64 vertically by the motor rotating the ball screw around its axis.

The moving mechanism 65 rotates a ball screw around its axis using a motor, moving the pair of clamping members 64 toward each other to clamp the expanded sheet 201 between them. The moving mechanism 65 also rotates the ball screw around its axis using a motor to move the pair of clamping members 64 toward each other to release the clamping of the expanded sheet 201 between them. Furthermore, the moving mechanism 65 can also move the pair of clamping members 64 vertically in the same direction by rotating the ball screw around its axis using a motor. The moving base 63, on which each pair of clamping members 64 (62-1, 62-2, 62-3, 62-4) and the moving mechanism 65 are provided, is mounted on the fixed base 31 so as to be movable in the first direction 212 or the second direction 213.

The mobile unit 70 comprises a first mobile unit 71 and a second mobile unit 72.

The first moving unit 71 moves the movable base 63 of the first clamping part 62-1 and the movable base 63 of the second clamping part 62-2 along the first direction 212, thereby moving the movable base 63 of the first clamping part 62-1 and the movable base 63 of the second clamping part 62-2 in directions away from each other and towards each other in the first direction 212. The first moving unit 71 also moves the clamping member 64 of the first clamping part 62-1 and the clamping member 64 of the second clamping part 62-2 in directions away from each other in the first direction 212 by moving the movable base 63 of the first clamping part 62-1 and the movable base 63 of the second clamping part 62-2 along the first direction 212, thereby moving the clamping member 64 of the first clamping part 62-1 and the clamping member 64 of the second clamping part 62-2 in directions away from each other in the first direction 212. The first moving unit 71 includes a first moving mechanism 73-1 that moves the movable base 63 of the first clamping portion 62-1 in the first direction 212, and a second moving mechanism 73-2 that moves the movable base 63 of the second clamping portion 62-2 in the first direction 212.

The second moving unit 72 moves the moving base 63 of the third clamping section 62-3 and the moving base 63 of the fourth clamping section 62-4 along the second direction 213, thereby moving the moving base 63 of the third clamping section 62-3 and the moving base 63 of the fourth clamping section 62-4 in directions away from each other and towards each other in the second direction 213. The second moving unit 72 also moves the moving base 63 of the third clamping section 62-3 and the moving base 63 of the fourth clamping section 62-4 along the second direction 213, thereby moving the clamping member 64 of the third clamping section 62-3 and the clamping member 64 of the fourth clamping section 62-4 so that they can move closer to and away from each other in the second direction 213. The second moving unit 72 includes a third moving mechanism 73-3 that moves the moving base 63 of the third clamping portion 62-3 in the second direction 213, and a fourth moving mechanism 73-4 that moves the moving base 63 of the fourth clamping portion 62-4 in the second direction 213.

The first moving mechanism 73-1, the second moving mechanism 73-2, the third moving mechanism 73-3, and the fourth moving mechanism 73-4 are substantially identical in structure, and therefore, the same reference numerals are used to denote the same parts.

The first moving mechanism 73-1, the second moving mechanism 73-2, the third moving mechanism 73-3, and the fourth moving mechanism 73-4 each have a motor that allows the moving base 63 of the clamping parts 62-1, 62-2, 62-3, and 62-4 to move in a first direction 212 or a second direction 213, and a ball screw that is rotated around its axis by the motor to move the moving base 63 in the first direction 212 or the second direction 213.

The first moving mechanism 73-1, the second moving mechanism 73-2, the third moving mechanism 73-3, and the fourth moving mechanism 73-4 expand the expanded sheet 201 held by the clamping parts 62-1, 62-2, 62-3, and 62-4 by moving the clamping parts 62-1, 62-2, 62-3, and 62-4 in directions away from each other.

The frame transport unit is positioned above the sheet clamping unit 61 and holds the annular frame 210 on its lower surface. The frame transport unit is provided to move vertically by a lifting unit and horizontally by a horizontal movement unit (not shown). The horizontal movement unit positions the annular frame 210 so that its opening 211, held on its lower surface, faces vertically towards the workpiece 200 attached to the expanded sheet 201 placed on the cooling table 41. The frame transport unit is then lowered by the lifting unit to attach the annular frame 210 to the expanded sheet 201.

The sheet cutting unit cuts the expanded sheet 201, which is attached to the annular frame 210, along the annular frame 210. After the annular frame 210 is attached to the expanded sheet 201, the sheet cutting unit cuts the expanded sheet 201 between the inner and outer edges of the annular frame 210.

The control unit 100 controls each component of the expander 1-2 to cause the expander 1-2 to perform operations such as attaching the workpiece 200 to the expander sheet 201, expanding the expander sheet 201, and attaching the annular frame 210 to the expander sheet 201. The control unit 100 is a computer comprising a arithmetic processing unit with a microprocessor such as a CPU (central processing unit), a storage device with memory such as ROM (read-only memory) or RAM (random access memory), and an input/output interface device. The arithmetic processing unit of the control unit 100 performs calculations according to the computer program stored in the storage device and outputs control signals for controlling the expander 1-2 to each component of the expander 1-2 via the input/output interface device.

Furthermore, the control unit 100 is connected to a display unit (not shown) which consists of a liquid crystal display device that displays the status of machining operations and images, and to an input unit (not shown) used by the operator to register machining content information. The input unit consists of at least one of the following: a touch panel provided on the display unit and an external input device such as a keyboard.

The expansion method according to Embodiment 2 is a method of expanding an expanded sheet 201 to which a workpiece 200 with a modified layer 207 formed on it is attached, thereby dividing the workpiece 200 into individual chips 202. The expansion method according to Embodiment 2 is carried out by a control unit 100 controlling each component of the expansion device 1-2, and, similar to Embodiment 1, includes a holding step 1001, a sheet cooling step 1002, and a dividing step 1003.

In Embodiment 2, the holding step 1001 is the step of holding the expanded sheet 201 by clamping it with the sheet clamping unit 61 of the expander 1-2. In Embodiment 2, during the holding step 1001, the expanded sheet 201 with the DAF 209 attached is placed on the contact surface 42 of the cooling table 41, and the expander 1-2 clamps the expanded sheet 201 placed on the contact surface 42 of the cooling table 41 with the clamping parts 62-1, 62-2, 62-3, and 62-4 of the sheet clamping unit 61. In Embodiment 2, during the holding step 1001, the workpiece transport unit attaches the workpiece 200 to the DAF 209 of the expanded sheet 201, which is clamped with the clamping parts 62-1, 62-2, 62-3, and 62-4 of the sheet clamping unit 61.

In Embodiment 2, the sheet cooling step 1002 is performed by bringing the expanded sheet 201 into contact with the contact surface 42 of the cooling table 41. In Embodiment 2, during the sheet cooling step 1002, as shown in Figure 10(A) or Figure 10(B), the expander 1-2 supplies power at a first voltage to the first Peltier element layer 46-1 via one polarity switching unit 49-1 of the power supply circuit 48, cooling the first region 43 to a first temperature, and the other polarity switching unit 49-1 of the power supply circuit 48 supplies power at a second voltage to the second Peltier element layer 46-2, cooling the second region 44 to a second temperature.

Thus, in Embodiment 2, in the sheet cooling step 1002, the expander 1-2 sets the first region 43 of the contact surface 42 to a first temperature and the second region 44 to a second temperature, cooling the region 217 of the expanded sheet 201 to which the workpiece 200 is attached, which is held by the sheet clamping unit 61, to the first temperature, and cooling the region 218 between the region 217 of the expanded sheet 201 to which the workpiece 200 is attached, which is held by the sheet clamping unit 61, and the clamping portions 62-1, 62-2, 62-3, 62-4, to the second temperature. Thus, in Embodiment 2, during the sheet cooling step 1002, the expander 1-2 cools the region 218 between the region 217 on the expanded sheet 201 where the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, and 62-4, so that it is cooler than the region 217 on the expanded sheet 201 where the workpiece 200 is attached.

In Embodiment 2, during the splitting step 1003, the expander 1-2, in the state shown in Figure 11, expands the expandable sheet 201 in the first direction 212 by moving the first clamping portion 62-1 and the second clamping portion 62-2 in the first direction 212, and expands the expandable sheet 201 in the second direction 213 by moving the third clamping portion 62-3 and the fourth clamping portion 62-4 in the second direction 213, using the second mover 72.

Then, in the splitting step 1003, as a result of the expansion, radial tensile forces act on the expanded sheet 201, and because the second temperature is lower than the first temperature, the region 217 to which the workpiece 200 is attached to the expanded sheet 201 expands beyond the region 218 between the region 217 to which the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, 62-4 of the expanded sheet 201. In Embodiment 2, in the splitting step 1003, because the modified layer 207 is formed along the planned splitting line 205, the workpiece 200 is split into individual devices 206 using the modified layer 207 as the fracture starting point, and is fragmented into individual chips 202. Furthermore, because the workpiece 200 fractures along the modified layer 207, the DAF 209 also fractures along the modified layer 207.

After the splitting step 1003, the expander 1-2 attaches the annular frame 210 to the expanded sheet 201 expanded by the frame transport unit, and then cuts the expanded sheet 201 between the inner and outer edges of the annular frame 210 using the sheet cutting unit, so that the workpiece 200 is discharged along with the expanded sheet 201 and the annular frame 210. After the workpiece 200 is discharged, as shown in Figure 13(A) or Figure 13(B), the other polarity switching unit 49-2 of the power supply circuit 48 supplies power to the first Peltier element layer 46-1 to heat the first region 43 to room temperature, and the other polarity switching unit 49-2 of the power supply circuit 48 supplies power to the second Peltier element layer 46-2 to heat the second region 44 to room temperature.

The expandable device 1-2 according to Embodiment 2 includes a cooling unit 40 that cools the region 217 of the expandable sheet 201 to which the workpiece 200 is attached to a first temperature, and cools the region 218 between the region 217 of the expandable sheet 201 to which the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, and 62-4 to a second temperature lower than the first temperature. Therefore, the expandable device 1 according to Embodiment 2 can cool the area between the region of the expandable sheet 201 to which the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, and 62-4 to a lower temperature than the region of the expandable sheet 201 to which the workpiece 200 is attached.

As a result, the expander 1-2 according to Embodiment 2, similar to Embodiment 1, can sufficiently expand the area 217 to which the workpiece 200 is attached to the expander sheet 201, thereby reducing the risk of undivided areas occurring in the workpiece 200.

Furthermore, the expansion method according to Embodiment 2 involves a sheet cooling step 1002 in which the region 217 of the expanded sheet 201 to which the workpiece 200 is attached is cooled to a first temperature, and the region 218 between the region 217 of the expanded sheet 201 to which the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, and 62-4 is cooled to a second temperature lower than the first temperature. This allows for sufficient expansion of the region of the expanded sheet 201 to which the workpiece 200 is attached, reducing the risk of undivided areas occurring in the workpiece 200.

[Variation]
An expandable device according to a modified embodiment of the present invention will be described with reference to the drawings. Figure 14 is a cross-sectional view showing the configuration of the cooling table of the expandable device according to a modified embodiment of the present invention. Note that in Figure 14, the same reference numerals are used for the same parts as in embodiment 2, and their descriptions are omitted.

The expander 1-2 according to Embodiment 2 is the same as that of Embodiment 2, except that the configuration of the cooling table 41-1 is different. As shown in Figures 14(A) and 14(B), the cooling table 41-1 of the expander 1-2 according to Embodiment 2 has only one Peltier element layer 46, each containing at least one Peltier element powered by a power supply circuit 48, placed on the table base 45, and the cooling plate 47 is composed of a first cooling plate 47-1 and a second cooling plate 47-2.

The planar shape of the Peltier element layer 46 is the same as the planar shape of the cooling table 41-1. The power supply circuit 48 includes a pair of polarity switching units 49-1 and 49-2, similar to Embodiment 2.

The first cooling plate 47-1 has a first region 43 on its upper surface and is made of resin. The second cooling plate 47-2 has a second region 44 on its upper surface and is made of metal, a material with higher thermal conductivity (i.e., better heat transfer) than the resin material that makes up the first cooling plate 47-1.

When the power supply circuit 48 supplies power from the DC power supply 50 of one polarity switching unit 49-1 to the Peltier element layer 46, the cooling table 41-1 cools the contact surface 42, i.e., regions 43 and 44, to a temperature lower than room temperature. When the power supply circuit 48 supplies power from the DC power supply 50 of the other polarity switching unit 49-2 to the Peltier element layers 46-1 and 46-2, the contact surface 42, i.e., regions 43 and 44, heats them to a temperature higher than room temperature.

Furthermore, when the power supply circuit 48 supplies power from the DC power supply 50 of one of the polarity switching units 49-1 to the Peltier element layer 46, the cooling table 41-1 cools the first region 43 to a first temperature and the second region 44 to a second temperature. Thus, the first region 43 of the contact surface 42 of the cooling table 41-1 shown in Figure 14 is set to a first temperature, and the second region 44 is set to a second temperature, which is lower than the first temperature.

The modified expansion device 1-2 includes a cooling unit 40 that cools the region 217 of the expanded sheet 201 to which the workpiece 200 is attached to a first temperature, and cools the region 218 between the region 217 of the expanded sheet 201 to which the workpiece 200 is attached and the clamping portions 62-1, 62-2, 62-3, and 62-4 to a second temperature lower than the first temperature. Therefore, similar to Embodiment 2, it has the effect of reducing the risk of undivided areas occurring in the workpiece 200.

Furthermore, in this invention, the modified cooling table 41-1 may be configured to include a cooling plate 47 similar to that in Embodiment 1, with a heat insulating material provided between the cooling plate 47 below the first region 43 and the Peltier element layer 46, and without a heat insulating material provided between the cooling plate 47 below the second region 44 and the Peltier element layer 46.

Furthermore, the present invention is not limited to the embodiments described above. That is, it can be implemented with various modifications without departing from the core principles of the invention. In the embodiments described above, a workpiece 200 with DAF 209 attached to its back surface 208, or a workpiece 200 with a metal film 214 formed on its back surface 208, was divided into individual chips 202, but the invention is not limited to this. For example, in the present invention, a workpiece 200 attached to an expanded sheet 201 may be pre-divided into individual chips 202 and have DAF 209 attached to its back surface 208, and the expanded sheet 201 may be expanded to divide the DAF 209 for each chip 202.

1,1-2 Expanding device 10,60 Expansion unit (expansion mechanism)
20, 40 Cooling unit 41, 41-1 Cooling table 42 Contact surface 43 First area 44 Second area 61 Sheet clamping unit 62-1 First clamping part 62-2 Second clamping part 62-3 Third clamping part 62-4 Fourth clamping part 71 First moving unit 72 Second moving unit 200 Workpiece 201 Expanded sheet (sheet)
207 Modified layer (starting point of splitting)
212 First direction 213 Second direction 215, 218 Region (region where the workpiece is not attached)
Areas 216 and 217 (areas to which the workpiece is attached)
1002 Sheet cooling step 1003 Splitting step

Claims (4)

An expandable device for dividing a workpiece by expanding a sheet to which a workpiece is attached, the outer edge of which is supported by a sheet mounted on the annular frame, and a dividing starting point is formed within the annular frame,
A frame holding unit having a frame holding member on which the annular frame is placed on the upper surface,
An expansion mechanism for extending the sheet,
The device includes a cooling unit that cools the area of the sheet to which the workpiece is not attached so that it is at a lower temperature than the area of the sheet to which the workpiece is attached.
The cooling unit is a disc-shaped expansion device having an outer diameter equal to the inner diameter of the frame holding member, positioned above the workpiece to which the annular frame is held by the frame holding unit , and separated from the workpiece, and facing the workpiece attached to the sheet, and injecting cooling air at a first temperature lower than room temperature toward the workpiece, and facing the area of the sheet to which the workpiece is not attached, and injecting cooling air at a second temperature lower than the first temperature toward the area of the sheet to which the workpiece is not attached. An expandable device that expands a sheet to which a workpiece is attached, on which a dividing point has been formed, to divide the workpiece,
An expansion mechanism for extending the sheet,
The device includes a cooling unit that cools the area of the sheet to which the workpiece is not attached so that it is at a lower temperature than the area of the sheet to which the workpiece is attached.
The expansion mechanism is,
A sheet clamping unit having a first clamping portion and a second clamping portion that are opposite to each other and clamp the sheet, respectively, with the workpiece sandwiched between them in a first direction, and a third clamping portion and a fourth clamping portion that are opposite to each other and clamp the sheet, respectively, with the workpiece sandwiched between them in a second direction perpendicular to the first direction,
A first moving unit moves the first clamping portion and the second clamping portion in directions that are separated from each other in the first direction,
The device comprises a second moving unit that moves the third clamping portion and the fourth clamping portion in directions that are separated from each other in the second direction,
The cooling unit includes a cooling table that has a contact surface that contacts the sheet held by the sheet clamping unit and cools the sheet.
The contact surface consists of a first region corresponding to the area to which the workpiece is attached, and a second region surrounding the first region, corresponding to the area between the workpiece and the first, second, third, and fourth clamping portions.
The cooling table comprises a first Peltier element layer overlapping the first region and a second Peltier element layer overlapping the second region and supplied with power independently of the first Peltier element layer.
An expander in which a first voltage is supplied to the first Peltier element layer, setting the first region to a first temperature, and a second voltage higher than the first voltage is supplied to the second Peltier element layer, setting the second region to a second temperature lower than the first temperature. An expanding method for dividing a workpiece by expanding a sheet to which a workpiece is attached, the outer edge of which is supported by a sheet mounted on the annular frame, and a dividing starting point is formed within the annular frame, the workpiece being divided
A sheet cooling step in which the area of the sheet to which the workpiece is not attached is cooled to a lower temperature than the area of the sheet to which the workpiece is attached,
The process includes a splitting step in which, after performing the sheet cooling step, the sheet is expanded to divide the workpiece,
Expanding method comprising: a sheet cooling step in which cooling air at a first temperature lower than room temperature is injected toward the workpiece from a first cooling air ejection hole facing the workpiece, which is attached to the sheet of a cooling unit and is positioned above the workpiece , with a distance between the workpiece and the workpiece, and the sheet having an outer diameter equal to the inner diameter of the frame holding member on which the annular frame is placed on the upper surface; and a second cooling air ejection hole facing the area of the sheet to which the workpiece is not attached, which is injected toward the area of the sheet to which the workpiece is not attached. An expansion method for dividing a workpiece by expanding a sheet to which a workpiece is attached, on which a dividing point has been formed,
A sheet cooling step in which the area of the sheet to which the workpiece is not attached is cooled to a lower temperature than the area of the sheet to which the workpiece is attached,
The process includes a splitting step in which, after performing the sheet cooling step, the sheet is expanded to divide the workpiece,
The sheet cooling step is carried out by bringing the cooling table into contact with the sheet.
The cooling table has a contact surface comprising a first region corresponding to the area to which the workpiece is attached, and a second region surrounding the first region, corresponding to the area between the workpiece and the first, second, third, and fourth clamping portions.
The cooling table comprises a first Peltier element layer overlapping the first region and a second Peltier element layer overlapping the second region and supplied with power independently of the first Peltier element layer.
A first voltage is supplied to the first Peltier element layer, setting the first region to a first temperature; a second voltage, higher than the first voltage, is supplied to the second Peltier element layer, setting the second region to a second temperature, lower than the first temperature.
In the dividing step, the sheet is expanded by moving a first clamping portion and a second clamping portion, which are positioned opposite each other and sandwiching the workpiece in a first direction, in a direction away from each other in the first direction, and moving a third clamping portion and a fourth clamping portion, which are positioned opposite each other and sandwiching the workpiece in a second direction perpendicular to the first direction, in a direction away from each other in the second direction.