JP7803789B2 - Protective member forming device - Google Patents

Description

The present invention relates to a protective member forming device.

In the protective member forming device described in Patent Document 1, liquid resin is supplied onto a sheet placed on the support surface of a glass table. The wafer is then held by the holding surface of a wafer holder positioned above the glass table, and the wafer holder is lowered to spread the liquid resin on the sheet with the wafer. The spread liquid resin is then hardened to form a protective member on the underside of the wafer. In such protective member forming devices, for example, if the liquid resin cannot be spread with the wafer, an operator must remove the sheet to which the liquid resin has been supplied, along with the liquid resin and wafer, from the glass table.

JP 2017-220548 A

During the sheet removal process, the liquid resin may adhere to the mounting surface of the glass table. The liquid resin may also adhere to the holding surface that holds the wafer. If the liquid resin adheres to the mounting surface or holding surface, it is difficult to form a uniform thickness on the protective member of the next wafer.
However, since the liquid resin is transparent, it is difficult for the human eye to detect that it has adhered to the placing surface or the holding surface.

Therefore, an object of the present invention is to effectively detect the presence of liquid resin on the mounting surface of a glass table or the holding surface of a wafer holding part.

The first protective member forming device of the present invention forms a protective member consisting of a sheet and UV-curable liquid resin that has been spread and cured over the entire surface of one side of a wafer. It includes: a glass table having a sheet-mounting surface on which the sheet is placed; a wafer holder that holds the wafer by its wafer-holding surface above the glass table; an elevation mechanism that raises and lowers the wafer holder; a liquid resin supply unit that supplies liquid resin onto the sheet; a camera; an ultraviolet irradiator that irradiates UV light onto the liquid resin; and a first control unit. The first control unit irradiates the sheet-mounting surface with UV light from the ultraviolet irradiator and captures an image of the sheet-mounting surface with the camera to obtain a first captured image. The first control unit further includes a first determination unit that determines that liquid resin is attached to the sheet-mounting surface of the glass table if the first captured image includes an image corresponding to light with a wavelength equal to or greater than the wavelength of the UV light irradiated from the UV irradiator.

In the first protective member forming device, the camera may be positioned below the glass table, and the ultraviolet light irradiation unit may be positioned below the glass table outside the camera's imaging area, and ultraviolet light may be irradiated onto the liquid resin through the glass table.

The first protective member forming device may further include a second control unit, which may lower the wafer holding unit to form a small gap between the sheet placement surface and the wafer holding surface, irradiate the wafer holding surface with ultraviolet light from the ultraviolet irradiation unit through the glass table, and capture an image of the wafer holding surface with the camera to obtain a second captured image. The first protective member forming device may further include a second determination unit that determines that liquid resin is attached to the wafer holding surface if the second captured image includes an image corresponding to light with a wavelength equal to or greater than the predetermined wavelength.

The second protective member forming device of the present invention is a protective member forming device that forms a protective member consisting of a sheet and UV-curable liquid resin that has been hardened by spreading it over the entire surface of one side of a wafer. The protective member forming device includes a wafer holding unit that holds the wafer using a wafer holding surface, a glass table that is positioned above the wafer holding unit, a sheet holding unit that is positioned outside the glass table, a liquid resin supply unit that supplies liquid resin onto the wafer held on the wafer holding surface, a camera, an ultraviolet irradiator that irradiates ultraviolet light onto the liquid resin on the wafer, and a protective member that includes the glass table, the sheet holding unit, and a protective member that includes the glass table, the sheet holding unit, and a protective member that includes the glass table, the glass table, the sheet holding unit, and a protective member that includes the glass table, the glass table, the protective member ... The device further comprises a third control unit and an elevating mechanism for raising and lowering the holding unit, the camera, and the ultraviolet irradiator. The third control unit irradiates the glass table with ultraviolet light from the ultraviolet irradiator and captures an image of the underside of the glass table with the camera to obtain a third captured image. The light reflected by the cured liquid resin changes to light with a wavelength equal to or greater than a predetermined wavelength that is different from the wavelength of the ultraviolet light irradiated from the ultraviolet irradiator. If the third captured image contains an image corresponding to light with a wavelength equal to or greater than the predetermined wavelength, the device further comprises a third determination unit.

In the second protective member forming device, the camera may be positioned above the glass table, and the ultraviolet light irradiation unit may be positioned above the glass table outside the camera's imaging area, and ultraviolet light may be irradiated onto the liquid resin through the glass table.

The second protective member forming device may further include a fourth control unit, which may lower the glass table, the sheet holding unit, the camera, and the ultraviolet light irradiation unit to form a small gap between the underside of the glass table and the wafer holding surface, irradiate the wafer holding surface with ultraviolet light from the ultraviolet light irradiation unit through the glass table, and capture an image of the wafer holding surface with the camera to obtain a fourth captured image. The second protective member forming device may further include a fourth determination unit that determines that liquid resin is attached to the wafer holding surface if the fourth captured image includes an image corresponding to light with a wavelength equal to or greater than the predetermined wavelength.

The first protective member forming device and the second protective member forming device acquire images of the sheet placement surface or the underside of the glass table, and images of the wafer holding surface. If these images contain images corresponding to light with wavelengths equal to or greater than a predetermined wavelength, it is determined that liquid resin is attached to the sheet placement surface, the underside of the glass table, or the wafer holding surface. This allows for accurate detection of the presence of liquid resin on these surfaces.

FIG. 2 is a perspective view showing a configuration of a first protective member forming device. 3A and 3B are explanatory views showing the configurations of a first wafer holding mechanism and a first sheet holding mechanism. FIG. 10 is an explanatory diagram showing a sheet placement surface to which liquid resin is attached. 10 is a graph showing an example of the G value of reflected light from a liquid resin attached to a sheet placement surface or a wafer holding surface, which changes over time. FIG. 2 is a perspective view showing a configuration of a second protective member forming device. 10A and 10B are explanatory views showing the configurations of a second sheet holding mechanism and a second wafer holding mechanism.

The first protective member forming apparatus 1 shown in Figure 1 is an apparatus that spreads ultraviolet-curable liquid resin over the entire surface of one side of a wafer 100 to form a protective member made of a sheet and the hardened resin.

Wafer 100 is, for example, a disk-shaped as-sliced silicon wafer. Wafer 100 is formed, for example, in a disk shape, and has a front surface 101 and a back surface 102. Back surface 102 and front surface 101 of wafer 100 correspond to examples of one side and the other side of wafer 100, respectively.

The first protective member forming device 1 comprises a housing 200, a device base 201 disposed within the housing 200, a column 202 erected on the device base 201, a support base 203 disposed adjacent to the device base 201, and a cassette storage body 204 connected to the rear end of the housing 200.

The cassette storage body 204 contains a cassette 207. The cassette 207 contains multiple wafers 100 before the protective member is formed, and multiple wafers 100 after the protective member is formed.

A temporary placement table 211 and a cutting table 212 located below the temporary placement table 211 are arranged on the -Y direction side of the cassette housing body 204. A sheet cutter 8 is arranged on the cutting table 212. The sheet cutter 8 cuts off excess sheet 12 along the outline of the wafer 100.

A first wafer transport mechanism 4 is disposed between the cassette storage body 204 and the temporary placement table 211. The first wafer transport mechanism 4 transports wafers 100 into and out of the cassette 207. That is, the first wafer transport mechanism 4 transports wafers 100, before the protective member is formed, from the cassette 207 and transports them into the temporary placement table 211. Furthermore, the first wafer transport mechanism 4 transports wafers 100, after the protective member is formed, from the cutting table 212 and transports them into the cassette 207.

The second wafer transport mechanism 5 is located on the -Y direction side of the first wafer transport mechanism 4. The second wafer transport mechanism 5 retrieves the wafer 100 on which the protective member has been formed and transports it to the cutting table 212. The second wafer transport mechanism 5 also transports the wafer 100 from the temporary placement table 211 and hands it over to the holding table 52 of the first wafer holding mechanism 50.

The device base 201 is equipped with a sheet supply mechanism 10 having a roll portion 11 containing a rolled sheet 12, a first sheet holding mechanism 20 including a glass table 21 that holds the sheet 12, and a first sheet placing mechanism 30.

The first sheet loading mechanism 30 includes an arm 31 extending in the X-axis direction intersecting the Y-axis direction, and a clamp 32 attached to the arm 31. The first sheet loading mechanism 30 clamps the sheet 12 wound around the roll 11 with the clamp 32, pulls it in the +Y direction with the arm 31, positions it on the glass table 21, and cuts it to a predetermined size. This allows the first sheet loading mechanism 30 to load the sheet 12 onto the glass table 21.

The first sheet holding mechanism 20 has a glass table 21 and a table support base 24 that supports the glass table 21. The glass table 21 has a sheet placement surface 22 on which the sheet 12 is placed. The glass table 21 and the sheet placement surface 22, which is the upper surface of the glass table 21, are made of glass, such as quartz glass. The sheet 12 is placed on this sheet placement surface 22 by the first sheet placement mechanism 30.

As shown in FIG. 2, a circular suction port 224 that is connected to the suction source 222 and the suction path 223 is provided around the sheet placement surface 22 of the glass table 21 in the first sheet holding mechanism 20. This suction port 224 is an example of a sheet holding unit located on the outside of the glass table 21. This suction port 224 allows the sheet placement surface 22 to suck and hold the sheet 12 using the suction force from the suction source 222.

As shown in FIG. 1, a first resin supply unit 40 is provided near the glass table 21 as a liquid resin supply unit that supplies liquid resin onto the sheet 12. The first resin supply unit 40 has a resin supply nozzle 41 for supplying liquid resin to the sheet 12. In this embodiment, the resin supply nozzle 41 is provided on the arm unit 31 of the first sheet placing mechanism 30 and moves in the Y-axis direction together with the arm unit 31. The first resin supply unit 40 uses this resin supply nozzle 41 to supply liquid resin sucked from a liquid resin tank (not shown) to the center of the upper surface of the sheet 12 held by the sheet placing surface 22 of the glass table 21.

In this embodiment, the liquid resin is an ultraviolet-curing resin used to form a protective member that protects the entire surface of the front surface 101 of the wafer 100. To form the protective member, the liquid resin is supplied onto a sheet 12 placed on the sheet placement surface 22 of the glass table 21, and the back surface 102 of the wafer 100 is pressed from above against the liquid resin, spreading the liquid resin over the entire surface of the back surface 102 and hardening the liquid resin.

On the -Y direction side of the column 202 are arranged a first wafer holding mechanism 50 that holds the wafer 100 transferred from the second wafer transfer mechanism 5, and an elevation mechanism 60 that raises and lowers the first wafer holding mechanism 50.

The first wafer holding mechanism 50 has a support structure 51 attached to a lifting mechanism 60, and a holding table 52 attached to the support structure 51. The support structure 51 is attached to the lifting mechanism 60 while supporting the holding table 52, and is moved in the Z-axis direction by the lifting mechanism 60.

1 and 2, the holding table 52 of the first wafer holding mechanism 50 has a wafer holding surface 53 disposed so as to face the sheet placing surface 22 of the glass table 21. The holding table 52 is an example of a wafer holding unit that holds the wafer 100 by the wafer holding surface 53 above the glass table 21.
The wafer holding surface 53 is made of, for example, a porous material. By connecting the wafer holding surface 53 to a suction source (not shown), the wafer holding surface 53 of the holding table 52 can suction-hold the front surface 101, which is the other surface of the wafer 100.

The lifting mechanism 60 shown in FIG. 1 raises and lowers the holding table 52. That is, the lifting mechanism 60 moves the first wafer holding mechanism 50, including the holding table 52, closer to the sheet placement surface 22 of the glass table 21 along the Z-axis direction, thereby spreading the liquid resin supplied onto the sheet 12 held on the sheet placement surface 22 over the entire back surface 102, which is one surface of the wafer 100 held on the holding table 52.

The lifting mechanism 60 includes a ball screw 61 extending in the Z-axis direction, a motor 62 connected to one end of the ball screw 61, a pair of guide rails 63 extending parallel to the ball screw 61, and a lifting plate 64 to which the first wafer holding mechanism 50 is attached. The lifting plate 64 is slidably mounted relative to the pair of guide rails 63. The lifting plate 64 also has a nut portion (not shown) into which the ball screw 61 is threaded.

In the lifting mechanism 60, the motor 62 rotates the ball screw 61, causing the lifting plate 64 to move in the Z-axis direction along a pair of guide rails 63 together with the first wafer holding mechanism 50. This allows the lifting mechanism 60 to raise and lower the first wafer holding mechanism 50 along the Z-axis direction, which is approximately perpendicular to the sheet placement surface 22 of the glass table 21. In this way, the lifting mechanism 60 can spread the liquid resin accumulated on the sheet placement surface 22 over the entire back surface 102 of the wafer 100.

As shown in FIG. 2, the first sheet holding mechanism 20 is provided below the glass table 21 with an ultraviolet irradiation unit 90 that irradiates ultraviolet light onto the liquid resin on the sheet placement surface 22 that has been spread over the entire back surface 102 of the wafer 100, and a camera 80. The camera 80 is a color camera capable of capturing color images of a subject. In this embodiment, the camera 80 is used to capture an image of the sheet placement surface 22 or the wafer holding surface 53.

In this embodiment, the camera 80 is positioned below the glass table 21. Multiple ultraviolet irradiation units 90 are arranged surrounding the camera 80.

The ultraviolet irradiation unit 90 irradiates the liquid resin with ultraviolet rays. That is, the ultraviolet irradiation unit 90 irradiates, for example, relatively strong ultraviolet rays via the glass table 21 onto the liquid resin that has been spread over the entire back surface 102 of the wafer 100 by the lifting mechanism 60, thereby hardening the liquid resin. In this way, the first protective member forming device 1 can harden the ultraviolet-curable liquid resin that has been spread over the entire back surface 102 of the wafer 100, thereby forming a protective member containing hardened resin and a sheet on the back surface 102 of the wafer 100.

The camera 80 is used to capture images of the sheet placement surface 22 or the wafer holding surface 53 from below using light from the ultraviolet light irradiation unit 90 when no sheet 12 is placed on the sheet placement surface 22 and no wafer 100 is held on the wafer holding surface 53. The ultraviolet light irradiation unit 90 is positioned below the glass table 21 and outside the imaging area of the camera 80 so as not to interfere with imaging by the camera 80.

The first protective member forming device 1 also has a touch panel 9, for example, on the side of the cassette housing body 204.

The touch panel 9 displays various information related to the first protective member forming device 1. The touch panel 9 is also used to set various pieces of information. In this way, the touch panel 9 functions as both an input member for inputting information and a display member for displaying information.

The first protective member forming device 1 is also equipped with a control unit 7 that controls each component of the first protective member forming device 1.

The control unit 7 includes a CPU that performs calculations according to a control program, and storage media such as memory. The control unit 7 controls the above-mentioned components of the first protective member forming apparatus 1 to perform various operations. For example, the control unit 7 performs a protective member forming operation on the wafer 100.

The control unit 7 also includes a first control unit 71, a second control unit 72, a first determination unit 73, and a second determination unit 74, which are used to perform a resin adhesion detection operation to determine whether liquid resin is adhering to the sheet placement surface 22 or the wafer holding surface 53.

The resin adhesion detection operation will be described below.
First, an overview of resin adhesion detection will be described. As shown in Figure 3, when liquid resin 300 adheres to the sheet placement surface 22 of the glass table 21, the liquid resin hardens when irradiated with ultraviolet light from the ultraviolet irradiation unit 90. Then, the light (fluorescence) reflected by the hardened liquid resin changes to light with a wavelength equal to or greater than a predetermined wavelength that is different from the wavelength of the ultraviolet light irradiated from the ultraviolet irradiation unit 90.

Here, the wavelength of the light reflected from the liquid resin attached to the sheet placement surface 22 or the wafer holding surface 53 corresponds to the value (G value; 256 levels) of the G component (G in RGB) of the reflected light. The G value of the reflected light gradually increases as the liquid resin hardens over time with the passage of ultraviolet irradiation time.

Figure 4 is a graph showing an example of the G value of reflected light as it changes over time as liquid resin attached to the sheet placement surface 22 or wafer holding surface 53 hardens. In the example shown in this figure, the wavelength of the ultraviolet light emitted from the ultraviolet irradiation unit 90 is 356 nm. In this case, the wavelength of the light reflected by the completely hardened liquid resin on the sheet placement surface 22 or wafer holding surface 53 is 430 nm, which corresponds to a G value of 236. Furthermore, the wavelength of the light reflected by the liquid resin immediately after hardening has begun is, for example, 400 nm, which corresponds to a G value of 190.

Therefore, a color image of the sheet placement surface 22 or wafer holding surface 53 is acquired by the camera 80, and using a G value of 190 as a threshold, it is possible to determine whether liquid resin is attached to the sheet placement surface 22 or wafer holding surface 53 based on the G value of the reflected light contained in this image. In other words, if the image contains an image (pixel) corresponding to light with a G value of 190 or greater (light with a predetermined wavelength of 400 nm or greater), it can be determined that liquid resin is attached to the sheet placement surface 22 or wafer holding surface 53.

Therefore, in the resin adhesion detection operation, first, a determination is made as to whether or not liquid resin has adhered to the sheet placement surface 22. That is, the first control unit 71 focuses the camera 80 on the sheet placement surface 22 of the glass table 21. Then, the first control unit 71 irradiates the sheet placement surface 22 with ultraviolet light from the ultraviolet irradiation unit 90, and captures an image of the sheet placement surface 22 with the camera 80. In this way, the first control unit 71 obtains a first captured image, which is an image of the sheet placement surface 22. Note that the imaging range in this image is, for example, the entire surface of the sheet placement surface 22.

Next, the first determination unit 73 determines whether the first captured image contains an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength (400 nm in the above example). This determination is made based on, for example, whether the first captured image contains an image corresponding to light with a G value of 190 or greater. If such an image is contained in the first captured image, the first determination unit 73 determines that liquid resin is attached to the sheet placement surface 22.

If the first determination unit 73 determines that liquid resin is adhering to the sheet placement surface 22, the control unit 7 uses the touch panel 9 to notify the worker by voice and/or image that liquid resin is adhering to the sheet placement surface 22.

After determining whether or not liquid resin has adhered to the sheet placement surface 22, a determination is made as to whether or not liquid resin has adhered to the wafer holding surface 53. Specifically, the second control unit 72 controls the lifting mechanism 60 to lower the holding table 52, creating a small gap between the wafer holding surface 53 of the holding table 52 and the sheet placement surface 22 of the glass table 21. In this state, the second control unit 72 focuses the camera 80 on the wafer holding surface 53. The second control unit 72 then irradiates the wafer holding surface 53 with ultraviolet light from the ultraviolet irradiation unit 90 via the glass table 21, and captures an image of the wafer holding surface 53 with the camera 80. The second control unit 72 thereby obtains a second captured image, which is an image of the wafer holding surface 53. The imaging range in this image is, for example, the entire surface of the wafer holding surface 53.

The second determination unit 74 then determines whether the second captured image contains an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength (400 nm in the above example). This determination is made based on, for example, whether the second captured image contains an image corresponding to light with a G value of 190 or greater. If such an image is contained in the second captured image, the second determination unit 74 determines that liquid resin is attached to the wafer holding surface 53.

If the second determination unit 74 determines that liquid resin is adhering to the wafer holding surface 53, the control unit 7 uses the touch panel 9 to notify the operator by voice and/or image that liquid resin is adhering to the wafer holding surface 53.

As described above, in this embodiment, a first image, which is an image of the sheet placement surface 22, and a second image, which is an image of the wafer holding surface 53, are acquired, and if these images contain an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength, it is determined that liquid resin is attached to the sheet placement surface 22 or the wafer holding surface 53. This makes it possible to accurately detect whether liquid resin is attached to the sheet placement surface 22 or the wafer holding surface 53.

In addition, in this embodiment, if liquid resin is found adhering to the sheet placement surface 22 or the wafer holding surface 53, this fact is displayed to the operator using the touch panel 9. This allows the operator to easily recognize that liquid resin is adhering to these surfaces. Furthermore, the operator can remove the adhering liquid resin and form a protective member on the wafer 100 without any liquid resin adhering to the sheet placement surface 22 or the wafer holding surface 53. This makes it possible to form a protective member of uniform thickness. In other words, it is possible to prevent the formation of a protective member of uneven thickness.

In the first protective member forming device 1, the camera 80 and ultraviolet ray irradiation unit 90 are disposed below the glass table 21. In this regard, the camera 80 may be installed in any position as long as it can capture images of the sheet placement surface 22 of the glass table 21 and the wafer holding surface 53 of the holding table 52. The ultraviolet ray irradiation unit 90 may also be installed in any position as long as it is outside the imaging area of the camera 80 and can irradiate ultraviolet rays onto the liquid resin spread on the back surface 102 of the wafer 100, the sheet placement surface 22, and the wafer holding surface 53.

The protective member forming apparatus according to this embodiment may also be the second protective member forming apparatus 2 shown in Figure 5. Similar to the first protective member forming apparatus 1, the second protective member forming apparatus 2 is an apparatus that forms a protective member made of a sheet and UV-curable liquid resin by spreading and hardening the resin over the entire surface of one side of the wafer 100.

The second protective member forming apparatus 2 shown in Figure 5 has the same configuration as the first protective member forming apparatus 1 shown in Figure 1, except that instead of the first sheet holding mechanism 20, first sheet placing mechanism 30, first resin supply unit 40, and first wafer holding mechanism 50, it has a second sheet holding mechanism 120, a second sheet placing mechanism 130, a second resin supply unit 140, and a second wafer holding mechanism 150.

As shown in FIG. 5, the device base 201 of the second protective member forming device 2 is equipped with the above-mentioned sheet supply mechanism 10 having the roll portion 11 of the sheet 12, a second sheet holding mechanism 120 that holds the sheet 12, a second sheet placing mechanism 130 that transfers the sheet to the second sheet holding mechanism 120, and a second wafer holding mechanism 150 that holds the wafer 100.

The second sheet placement mechanism 130 includes a conveying table 135 having a circular elastic member 136 made of, for example, sponge, and a sheet placement mechanism 132 having a gripping portion 133 that grips the sheet 12. The sheet placement mechanism 132 grips the outer periphery of the sheet 12 from the roll portion 11 in the sheet supply mechanism 10 with the gripping portion 133 and pulls it out horizontally (+Y direction), and positions the sheet 12 so that it covers the elastic member 136 of the conveying table 135, and can cut it to a predetermined size.

The second sheet placement mechanism 130 also has a table movement mechanism 131 that moves the transport table 135 along the Y-axis direction. The table movement mechanism 131 can position the transport table 135, which has an elastic member 136 covered by the sheet 12, below the second sheet holding mechanism 120.

The second sheet holding mechanism 120 is attached to the lifting plate 64 of the lifting mechanism 60 via a support structure 65 and is configured to be raised and lowered by the lifting mechanism 60.

As shown in FIG. 6 , the second sheet holding mechanism 120 has a glass table 121 positioned above the second wafer holding mechanism 150 and a table support 124 that supports the glass table 121. The glass table 121 has a sheet holding surface 122 that holds the sheet 12. The glass table 121 and the sheet holding surface 122, which is the underside of the glass table 121, are made of glass, such as quartz glass.

Furthermore, as shown in FIG. 6, a circular suction port 224 that communicates with a suction source 222 and a suction path 223 is provided around the sheet holding surface 122 of the glass table 121 in the second sheet holding mechanism 120. The suction port 224 is an example of a sheet holding section that is arranged on the outside of the glass table.

When the conveying table 135 having the elastic member 136 covered by the sheet 12 is positioned below the second sheet holding mechanism 120, the second sheet holding mechanism 120 is moved downward by the lifting mechanism 60. As a result, the sheet holding surface 122 of the second sheet holding mechanism 120 comes into contact with the sheet 12 covering the elastic member 136, pressing against the elastic member 136 via the sheet 12. In this state, by applying suction force from the suction source 222 to the suction port 224, the sheet holding surface 122 can suction and hold the sheet 12 on the elastic member 136.

In the second protective member forming device 2, the lifting mechanism 60 is configured to raise and lower the second sheet holding mechanism 120, which includes the glass table 121, suction port 224, camera 80, and ultraviolet light irradiation unit 90. The second sheet holding mechanism 120, which holds the sheet 12 by suction using the sheet holding surface 122, is moved upward by the lifting mechanism 60.

In addition, a second wafer holding mechanism 150 is disposed below the second sheet holding mechanism 120. The second wafer holding mechanism 150 holds the wafer 100 that has been transferred from the temporary placement table 211 by the second wafer transport mechanism 5.

As shown in Figure 6, the second wafer holding mechanism 150 is a pin chuck-type holding table and has a frame 153 with a concave space. A plurality of support pins 155 are provided in the concave space of the frame 153. The upper end surfaces of these support pins 155 form the circular wafer holding surface 152 shown in Figure 1.

Thus, the second wafer holding mechanism 150 is an example of a wafer holding unit that holds the wafer 100 by means of the wafer holding surface 152. That is, in the second wafer holding mechanism 150, the recessed space of the frame 153 is connected to a suction source (not shown), so that the wafer holding surface 152, which is the upper end surface of the multiple support pins 155, can hold the front surface 101, which is the other surface of the wafer 100, by suction.
The second wafer holding mechanism 150 may be a porous chuck type holding table having a holding surface made of a porous material.

As shown in FIG. 5, a second resin supply unit 140 is provided near the second wafer holding mechanism 150 as a liquid resin supply unit that supplies liquid resin onto the wafer 100 held on the wafer holding surface 152. The second resin supply unit 140 has a resin supply nozzle 141 for supplying liquid resin to the sheet 12. In this embodiment, the resin supply nozzle 141 is configured to supply liquid resin sucked from a liquid resin tank (not shown) to the center of the back surface 102, which is the upper surface of the wafer 100 held by the wafer holding surface 152 of the second wafer holding mechanism 150.

In the second protective member forming device 2, while liquid resin is supplied to the wafer 100 held by the second wafer holding mechanism 150 and the sheet holding surface 122 (see Figure 6) of the second sheet holding mechanism 120 holds the sheet, the lifting mechanism 60 moves the second sheet holding mechanism 120 closer to the wafer 100 along the Z-axis direction, pressing the sheet holding surface 122 holding the sheet 12 against the liquid resin on the wafer 100. This allows the liquid resin to be spread over the entire back surface 102, which is one of the surfaces of the wafer 100.

As shown in FIG. 6, the second sheet holding mechanism 120 is also provided with the aforementioned ultraviolet irradiation unit 90 above the glass table 121, which irradiates ultraviolet light onto the liquid resin on the sheet holding surface 122 that has been spread over the entire back surface 102 of the wafer 100, and the aforementioned camera 80 for capturing an image of the sheet holding surface 122 or the wafer holding surface 152, which is the underside of the glass table 121.

In the second protective member forming device 2, the camera 80 is positioned above the glass table 121. Multiple ultraviolet irradiation units 90 are arranged surrounding the camera 80.

As described above, the ultraviolet irradiation unit 90 cures the liquid resin that has been spread over the entire back surface 102 of the wafer 100 by the lifting mechanism 60, by irradiating it with relatively strong ultraviolet light via the glass table 121. In this way, the second protective member forming device 2 cures the ultraviolet-curable liquid resin that has been spread over the entire back surface 102 of the wafer 100, thereby forming a protective member containing the cured resin and the sheet on the back surface 102 of the wafer 100.

When no sheet 12 is held on the sheet holding surface 122 and no wafer 100 is held on the wafer holding surface 152, the camera 80 is used to capture an image of the sheet holding surface 122 or the wafer holding surface 152 from above using light from the ultraviolet light irradiation unit 90. Note that in the second protective member forming device 2, the ultraviolet light irradiation unit 90 is also positioned above the glass table 121 and outside the imaging area of the camera 80 so as not to interfere with imaging by the camera 80.

Furthermore, as shown in FIG. 5, in the second protective member forming device 2, the control unit 7 is equipped with a third control unit 75, a fourth control unit 76, a third determination unit 77, and a fourth determination unit 78, which are used to perform a resin adhesion detection operation to determine whether liquid resin is adhering to the sheet holding surface 122 or the wafer holding surface 152.

The resin adhesion detection operation in the second protective member forming device 2 will be described below.
As in the case of the first protective member forming device 1 described above, in the resin adhesion detection operation in the second protective member forming device 2, a color image of the sheet holding surface 122 or the wafer holding surface 152 is acquired by the camera 80, and the presence or absence of liquid resin is determined based on the G value of reflected light contained in this image, using a G value of 190 as a threshold. In other words, if the image contains an image (pixel) corresponding to light with a G value of 190 or more (light with a predetermined wavelength of 400 nm or more), it is determined that liquid resin is adhered to the sheet holding surface 122 or the wafer holding surface 152.

Specifically, the resin adhesion detection operation in the second protective member forming device 2 first determines whether liquid resin is attached to the sheet holding surface 122, which is the underside of the glass table 121. That is, the third control unit 75 focuses the camera 80 on the sheet holding surface 122 of the glass table 121. The third control unit 75 then irradiates the glass table 121 with ultraviolet light from the ultraviolet irradiation unit 90, and causes the camera 80 to capture an image of the sheet holding surface 122, which is the underside of the glass table 121. As a result, the third control unit 75 obtains a third captured image, which is an image of the sheet holding surface 122. Note that the imaging range in this image is, for example, the entire surface of the sheet holding surface 122.

Next, the third determination unit 77 determines whether the third captured image contains an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength (400 nm in the above example). This determination is made based on, for example, whether the third captured image contains an image corresponding to light with a G value of 190 or greater. If such an image is contained in the third captured image, the third determination unit 77 determines that liquid resin is attached to the sheet holding surface 122.

If the third determination unit 77 determines that liquid resin is adhering to the sheet holding surface 122, the control unit 7 uses the touch panel 9 to notify the worker by voice and/or image that liquid resin is adhering to the sheet holding surface 122.

After determining whether or not liquid resin is adhering to the sheet holding surface 122, a determination is made as to whether or not liquid resin is adhering to the wafer holding surface 152. Specifically, the fourth control unit 76 controls the lifting mechanism 60 to lower the second sheet holding mechanism 120, which includes the glass table 121, suction port 224, camera 80, and ultraviolet light irradiation unit 90. As a result, the fourth control unit 76 creates a small gap between the wafer holding surface 152 of the second wafer holding mechanism 150 and the sheet holding surface 122 of the glass table 121. In this state, the fourth control unit 76 focuses the camera 80 on the wafer holding surface 152. The fourth control unit 76 then irradiates ultraviolet light from the ultraviolet light irradiation unit 90 onto the wafer holding surface 152 via the glass table 121, and captures an image of the wafer holding surface 152 with the camera 80. As a result, the fourth control unit 76 acquires a fourth captured image, which is an image of the wafer holding surface 152. The imaging range in this imaging is, for example, the entire surface of the wafer holding surface 152.

Next, the fourth determination unit 78 determines whether the fourth captured image contains an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength (400 nm in the above example). This determination is made based on, for example, whether the fourth captured image contains an image corresponding to light with a G value of 190 or greater. If such an image is contained in the fourth captured image, the fourth determination unit 78 determines that liquid resin is attached to the wafer holding surface 152.

If the fourth determination unit 78 determines that liquid resin is adhering to the wafer holding surface 152, the control unit 7 uses the touch panel 9 to notify the operator by voice and/or image that liquid resin is adhering to the wafer holding surface 152.

In this way, the second protective member forming device 2 also acquires a third image, which is an image of the sheet holding surface 122, and a fourth image, which is an image of the wafer holding surface 152. If these images contain an image corresponding to light with a wavelength equal to or greater than a predetermined wavelength, it is determined that liquid resin has adhered to the sheet holding surface 122 or the wafer holding surface 152. This makes it possible to accurately detect whether liquid resin has adhered to the sheet holding surface 122 or the wafer holding surface 152.

In addition, in this embodiment, if liquid resin is found adhering to the sheet holding surface 122 or the wafer holding surface 152, this fact is displayed to the operator using the touch panel 9. This allows the operator to easily recognize that liquid resin is adhering to these surfaces. Furthermore, the operator can remove the adhering liquid resin and form the protective member on the wafer 100 without any liquid resin adhering to the sheet holding surface 122 or the wafer holding surface 152. This makes it possible to form a protective member of uniform thickness.

In the second protective member forming apparatus 2, the camera 80 and the ultraviolet ray irradiation unit 90 are disposed above the glass table 121. In this regard, the camera 80 may be installed at any position as long as it is able to capture images of the sheet holding surface 122, which is the underside of the glass table 121, and the wafer holding surface 152 of the second wafer holding mechanism 150. The ultraviolet ray irradiation unit 90 may also be installed at any position as long as it is outside the imaging area of the camera 80 and is able to irradiate ultraviolet rays onto the liquid resin spread on the back surface 102 of the wafer 100, the sheet holding surface 122, and the wafer holding surface 152.
Since the camera 80 only needs to be able to capture images of the wafer holding surface 152 and the sheet holding surface 122, the camera 80 may be placed on an arm extending horizontally and the arm may be rotated so as to capture images of the wafer holding surface 152 and the sheet holding surface 122 separately.

In addition, with the first protective member forming device 1 and the second protective member forming device 2, the smaller the pixels of the color image captured by the camera 80, the smaller the resin that can be detected. For example, if one pixel is 1 μm, then 1 μm of resin can be detected from the captured image. Therefore, it is preferable that the pixels of the camera 80 are as small as possible.

1: first protective member forming device, 2: second protective member forming device, 4: first wafer transport mechanism,
5: second wafer transport mechanism, 7: control unit, 8: sheet cutter, 9: touch panel,
10: sheet supply mechanism, 11: roll unit, 12: sheet, 20: first sheet holding mechanism,
21: glass table, 22: sheet placement surface, 24: table support base,
30: first sheet placing mechanism, 31: arm portion, 32: clamp portion,
40: first resin supply unit, 41: resin supply nozzle,
50: first wafer holding mechanism, 51: support structure, 52: holding table,
53: wafer holding surface, 60: lifting mechanism, 61: ball screw, 62: motor,
63: guide rail, 64: lifting plate, 65: support structure, 71: first control unit,
72: second control unit, 73: first determination unit, 74: second determination unit, 75: third control unit,
76: Fourth control unit, 77: Third determination unit, 78: Fourth determination unit, 80: Camera,
90: ultraviolet irradiation unit, 100: wafer, 101: front surface, 102: back surface,
120: second sheet holding mechanism, 121: glass table, 122: sheet holding surface,
124: table support base, 130: second sheet placement mechanism, 131: table movement mechanism,
132: sheet placement mechanism, 133: gripping portion, 135: conveying table, 136: elastic member,
140: second resin supply unit, 141: resin supply nozzle, 150: second wafer holding mechanism,
152: wafer holding surface, 153: frame, 155: support pin, 190: G value,
200: housing, 201: device base, 202: column, 203: support base,
204: cassette storage body, 207: cassette, 211: temporary placement table,
212: cutting table, 222: suction source, 223: suction path, 224: suction port,
300: Liquid resin

Claims (6)

A protective member forming apparatus for forming a protective member made of a sheet and an ultraviolet-curable liquid resin by spreading the resin over the entire surface of one side of a wafer,
a glass table having a sheet placement surface on which a sheet is placed;
a wafer holder that holds a wafer by a wafer holding surface above the glass table;
a lifting mechanism for lifting and lowering the wafer holder;
a liquid resin supply unit that supplies a liquid resin onto the sheet;
A camera and
an ultraviolet irradiation unit that irradiates the liquid resin with ultraviolet rays;
a first control unit;
the first control unit irradiates the sheet placement surface with ultraviolet light from the ultraviolet light irradiation unit, and acquires a first captured image by capturing an image of the sheet placement surface with the camera;
The light reflected by the cured liquid resin is changed into light having a wavelength equal to or greater than a predetermined wavelength that is different from the wavelength of the ultraviolet light irradiated from the ultraviolet light irradiating unit,
a first determination unit that determines that liquid resin is attached to the sheet placement surface of the glass table if the first captured image includes an image corresponding to light having a wavelength equal to or greater than the predetermined wavelength;
Protective member forming device. The camera is disposed below the glass table,
the ultraviolet ray irradiation unit is disposed below the glass table and outside the imaging area of the camera, and irradiates the liquid resin with ultraviolet rays through the glass table;
The protective member forming apparatus according to claim 1 . Further comprising a second control unit,
the second control unit lowers the wafer holding unit to form a small gap between the sheet placement surface and the wafer holding surface, irradiates the wafer holding surface with ultraviolet light from the ultraviolet irradiation unit through the glass table, and captures an image of the wafer holding surface with the camera to obtain a second captured image;
a second determination unit that determines that liquid resin is attached to the wafer holding surface if the second captured image includes an image corresponding to light having a wavelength equal to or greater than the predetermined wavelength;
The protective member forming apparatus according to claim 1 or 2. A protective member forming apparatus for forming a protective member made of a sheet and an ultraviolet-curable liquid resin by spreading the resin over the entire surface of one side of a wafer,
a wafer holding portion that holds a wafer by a wafer holding surface;
a glass table disposed above the wafer holder;
a sheet holding unit disposed outside the glass table;
a liquid resin supply unit that supplies a liquid resin onto the wafer held on the wafer holding surface;
A camera and
an ultraviolet irradiation unit that irradiates ultraviolet rays onto the liquid resin on the wafer;
a lifting mechanism for lifting up and down the glass table, the sheet holding unit, the camera, and the ultraviolet ray irradiation unit;
a third control unit;
the third control unit irradiates the glass table with ultraviolet light from the ultraviolet light irradiation unit, and acquires a third captured image by capturing an image of the underside of the glass table with the camera;
The light reflected by the cured liquid resin is changed into light having a wavelength equal to or greater than a predetermined wavelength that is different from the wavelength of the ultraviolet light irradiated from the ultraviolet light irradiating unit,
a third determination unit that determines that liquid resin is attached to the underside of the glass table if the third captured image includes an image corresponding to light having a wavelength equal to or longer than the predetermined wavelength;
Protective member forming device. The camera is disposed above the glass table,
the ultraviolet ray irradiation unit is disposed above the glass table and outside the imaging area of the camera, and irradiates the liquid resin with ultraviolet rays through the glass table;
The protective member forming apparatus according to claim 4. Further comprising a fourth control unit,
the fourth control unit lowers the glass table, the sheet holding unit, the camera, and the ultraviolet ray irradiation unit, and in a state in which a small gap is formed between the lower surface of the glass table and the wafer holding surface, irradiates the wafer holding surface with ultraviolet rays from the ultraviolet ray irradiation unit through the glass table, and captures an image of the wafer holding surface with the camera, thereby obtaining a fourth captured image;
a fourth determination unit that determines that liquid resin is attached to the wafer holding surface if the fourth captured image includes an image corresponding to light having a wavelength equal to or greater than the predetermined wavelength;
The protective member forming apparatus according to claim 4 or 5.