JP6506797B2 - Grinding apparatus and grinding method - Google Patents

Description

  The present invention relates to a grinding apparatus and a grinding method.

  For example, the following grinding method is disclosed by patent document 1 (Unexamined-Japanese-Patent No. 2014-165339). First, the semiconductor device wafer side of the laminated wafer is held by suction by the chuck table of the grinding apparatus to expose the sealing resin. Next, a grinding fluid not containing abrasive grains is supplied onto the surface of the sealing resin of the laminated wafer. Next, while rotating the chuck table holding the laminated wafer by suction and rotating the grinding wheel having a plurality of grinding wheels fixed to the lower end of the ring base, the grinding wheels are brought into contact with the surface of the sealing resin Grind the sealing resin.

JP, 2014-165339, A

  However, in the grinding method described in Patent Document 1, it is necessary to dress the grinding wheel because the grinding property of the grinding wheel is reduced due to clogging of the grinding wheel or the like as the sealing resin is ground. However, since dressing of the grinding wheel takes time and cost, it is desired to reduce the number of dressings of the grinding wheel.

  According to an embodiment disclosed herein, there is provided a grinding apparatus comprising a rotatable grinding portion in which a grinding wheel is annularly arranged, wherein the grinding wheel is a grinding area for grinding an object to be ground during grinding of the object to be ground And the non-grind area where the object to be ground is not ground co-exist, and the grinding apparatus is further configured with a fine bubble water generator configured to produce fine bubble water; And a fine bubble water supply unit configured to be able to supply fine bubble water to the grinding apparatus.

  According to an embodiment disclosed herein, there is provided a grinding method including the steps of rotating a grinding portion on which a grinding wheel is arranged annularly and grinding an object to be ground with the grinding wheel, wherein the grinding wheel is in the process of grinding the grinding object Are arranged so that the grinding area for grinding the object to be ground and the non-grinding area for not grinding the object coexist, and the fine bubble water generator generates fine bubble water and supplies it to the fine bubble water supply unit And a step of supplying fine bubble water to the grinding wheel in the non-grinding region.

  According to the embodiment disclosed herein, it is possible to reduce the number of dressings of the grinding wheel.

It is a typical side view of a grinding device of an embodiment. FIG. 2 is a schematic plan view of the bottom of the wheel mount shown in FIG. 1; FIG. 2 is a schematic plan view of the grinding wheel shown in FIG. 1; FIG. 6 is a schematic side view illustrating an example of a method of attaching a grinding wheel to a wheel mount. It is a schematic plan view of the fine bubble water supply part shown by FIG. It is a schematic plan view of the end face of the fine bubble water supply part shown by FIG. It is a typical sectional view illustrating the grinding method of an embodiment. It is a typical perspective view illustrating the grinding method of an embodiment. It is a schematic plan view illustrating the grinding method of an embodiment. It is a typical expanded sectional view which illustrates an example of the method of wash | cleaning a grindstone in embodiment. It is a schematic plan view illustrating an example of the relation between the jet direction of fine bubble water and the rotation direction of a grinding part in an embodiment.

  Hereinafter, embodiments will be described. In the drawings used for describing the embodiments, the same reference numerals represent the same or corresponding portions.

  FIG. 1 shows a schematic side view of a grinding apparatus according to an embodiment which is an example of the grinding apparatus of the present invention. The grinding apparatus according to the embodiment includes a base 1, a pillar 10 extending in the Z direction (vertically upward direction) from an area of an end of the base 1, and an end of the pillar 10 opposite to the end on the base 1 side The connecting portion 9 extending in the X direction from the portion, the motor 8 attached to the end of the connecting portion 9 in the X direction, and a spindle having one end attached to the motor 8 and extending in the Z direction (vertical downward direction) And a grinding portion 11 attached to the end of the spindle 7 opposite to the end on the motor 8 side. The grinding portion 11 is rotatable around an axis extending in the Z direction.

  The grinding apparatus according to the embodiment also includes a stage 2 disposed on the base 1 at a distance from the column portion 10 in the X direction (horizontal direction) to ground the object 3 to be ground, and grinding the object 3 to be ground And a grinding fluid supply unit 4 configured to supply the grinding fluid to the surface. The configuration of the grinding fluid supply unit 4 is not particularly limited as long as the grinding fluid can be supplied to the grinding surface of the object 3 to be ground.

  The grinding portion 11 includes a wheel mount 6 having a circular bottom surface 6 a and an annular grinding wheel 16 attached to the bottom surface 6 a of the wheel mount 6. The grinding wheel 16 comprises an annular annular base 15 and a plurality of grinding wheels 5 spaced apart from one another on the annular base 15. The grindstone 5 is arranged such that a grinding area 41 for grinding the grinding object 3 and an ungrind area 42 for not grinding the grinding object 3 coexist while grinding the grinding object 3. The annular grinding wheel 16 can be mounted, for example, on the periphery of the bottom surface 6 a of the wheel mount 6 such that the grinding wheels 5 are spaced apart from one another. The grinding apparatus of the embodiment also includes a cover (not shown) surrounding the outer periphery of the grinding portion 11.

  The grinding apparatus according to the embodiment also includes a fine bubble water supply unit 12 attached so as to hang from a part of the cover in the Z direction (vertical downward direction), and a fine bubble water generator for generating fine bubble water. And a hose 13 for connecting the fine bubble water supply unit 12 and the fine bubble water generator 14 to supply the fine bubble water from the fine bubble water generator 14 to the fine bubble water supply unit 12 . The fine bubble water discharger 12c of the fine bubble water supply unit 12 corresponds to the installation location of the object 3 to be ground from the viewpoint of suppressing the drainage of the fine bubble water after cleaning from adhering to the object 3 to be ground It is preferably located above the area other than the area 22 (for example, the area 23).

  The configuration of the fine bubble water generator 14 is not particularly limited as long as it can generate fine bubble water and supply the fine bubble water to the fine bubble water supply unit 12. Fine bubble water is water containing fine bubbles which are bubbles having a diameter of 100 μm or less. Fine bubbles include microbubbles with a diameter of 1 μm to 100 μm and ultrafine bubbles with a diameter of less than 1 μm, and also include air bubbles called nanobubbles and micronanobubbles.

  FIG. 2 shows a schematic plan view of the bottom surface 6a of the wheel mount 6 shown in FIG. As shown in FIG. 2, the bottom surface 6 a of the wheel mount 6 is circular, and the cover 21 is positioned so as to surround the outer periphery of the bottom surface 6 a of the circular wheel mount 6.

  FIG. 3 shows a schematic plan view of the grinding wheel 16 shown in FIG. As shown in FIG. 3, the grinding wheel 16 is provided with an annular annular base 15 and a plurality of grinding wheels 5 on the annular base 15. The plurality of grindstones 5 are arranged annularly along the shape of the annular base 15 with a gap from the adjacent grindstones 5 respectively.

  FIG. 4 shows a schematic side view illustrating an example of a method of attaching the grinding wheel 16 to the wheel mount 6. The grinding wheel 16 is attached to the bottom surface 6 a of the wheel mount 6, for example, on the surface of the annular base 15 on the side where the grinding wheel 5 is not disposed. The grinding wheel 16 is fixed to the bottom surface 6 a of the wheel mount 6 by a method such as screwing.

  FIG. 5 shows a schematic plan view of the fine bubble water supply unit 12 shown in FIG. As shown in FIG. 5, the fine bubble water supply unit 12 includes a fine bubble water supply unit attachment unit 12a, a fine bubble water storage unit 12b, a fine bubble water supply unit attachment unit 12a, and a fine bubble water storage unit 12b. And a connecting portion 12g to be connected. When the planar shape of the fine bubble water supply unit 12 (in the present embodiment, the fine bubble water supply unit attachment unit 12a, the fine bubble water storage unit 12b, and the connection unit 12g) is curved in an arc as shown in FIG. Although it is possible, it is not limited to this shape.

  The fine bubble water supply portion attachment portion 12a is a wall-shaped member extending vertically upward, and is connected to the fine bubble water storage portion 12b by the connection portion 12g. Therefore, a space is provided between the fine bubble water supply portion attachment portion 12a and the fine bubble water storage portion 12b by the amount of the connection portion 12g.

  The fine bubble water storage portion 12b is configured to penetrate between a bottom portion 12e, a pair of wall portions 12f extending vertically upward from both ends of the bottom portion 12e, and an upper surface and a lower surface of the bottom portion 12e. A bubble water supply hole 31 is provided. The height of the wall portion 12f can be, for example, a height at which the grindstone 5 of the grinding wheel 16 can be immersed in the fine bubble water when the fine bubble water is accommodated in the fine bubble water container 12b. For example, as shown in FIG. 5, a plurality of fine bubble water supply holes 31 are provided in the bottom portion 12e at a distance from each other, but the number of fine bubble water supply holes 31 is not limited to this. .

  In FIG. 6, the typical top view of the end surface of the fine bubble water supply part 12 shown by FIG. 5 is shown. As shown in FIG. 6, the end face of the fine bubble water storage unit 12b has a fine bubble water discharge unit 12c. The fine bubble water discharger 12 c is an opening for discharging the fine bubble water accommodated in the fine bubble water container 12 b to the outside of the fine bubble water supplier 12. The end face of the fine bubble water container 12b may have an end wall 12d that prevents the fine bubble water from being discharged to the outside.

  FIG. 7 is a schematic cross-sectional view illustrating the grinding method of the embodiment which is an example of the grinding method using the grinding device of the embodiment. The grinding method of the embodiment can be performed, for example, as follows.

  First, the fine bubble water supply portion attachment portion 12 a of the fine bubble water supply portion 12 is attached to the cover 21 surrounding the grinding portion 11. Next, the object to be ground 3 is placed on the stage 2.

  As the object to be ground 3, for example, one provided with the support member 3a and the sealing resin 3b on the support member 3a can be used. The supporting member 3a is a member for supporting a chip and / or a thin film, and for example, a lead frame, a substrate, an interposer, a semiconductor substrate (silicon wafer etc.), a metal substrate, a glass substrate, a ceramic substrate, a resin substrate and a wiring The wiring may or may not be provided including at least one substrate selected from the group consisting of substrates. The sealing resin 3 b is a resin that seals at least one surface of a chip and / or a thin film supported by the support member 3 a.

  Next, the fine bubble water 32 is generated by the fine bubble water generator 14 and supplied to the fine bubble water supply unit 12. The fine bubble water 32 is supplied to the fine bubble water storage unit 12 b through the fine bubble water supply hole 31 provided in the bottom 12 e of the fine bubble water storage unit 12 b.

  Thereafter, the grinding portion 11 is rotated in the first direction 45 about the axis 43, and the stage 2 on which the object 3 to be ground is installed is the second direction 46 opposite to the first direction 45 about the axis 44. Rotate to. At this time, the grindstone 5 of the grinding area 41 grinds the object to be ground 3 while the grindstone 5 of the non-grinding area 42 does not grind the object to be ground 3 fine bubble water stored in the fine bubble water storage portion 12b. Soak in 32. Here, the grinding portion 11 can be rotated in the second direction 46 about the shaft 43 and the stage 2 can be rotated in the first direction 45 about the shaft 44. The direction of rotation may be the same as the first direction 45 or the second direction 46.

  Grinding of the object 3 to be ground can be performed, for example, so as to grind at least a part of the sealing resin 3b so as to reduce the thickness of the object 3 to be ground. Further, although not shown in FIG. 7, it is also possible to grind the object to be ground 3 while supplying the grinding fluid from the grinding fluid supply unit 4 to the grinding surface of the object to be ground 3. Also, while the grinding wheel 5 in the non-grinding area 42 is immersed in the fine bubble water 32, during grinding of the grinding object 3, the fine bubble water is from above the area 23 other than the area 22 where the grinding object 3 is disposed. Fine bubble water 32 can be discharged through the fine bubble water discharger 12 c at the end face of the supply unit 12.

  Thus, as shown in the schematic perspective view of FIG. 8 and the schematic plan view of FIG. 9, for example, the grindstone 5 of the grinding unit 11 according to the embodiment grinds the object to be ground 3 in the grinding area 41 and And alternate immersion in fine bubble water 32 in the non-grind area 42. Thereby, compared with the case where the grindstone 5 of the grinding part 11 of the embodiment is not immersed in the fine bubble water 32, the occurrence frequency of the phenomenon that the grindability of the grindstone 5 is deteriorated such as clogging of the grindstone 5 is reduced. be able to. Therefore, the number of times of dressing the grinding stone 5 can be reduced by stopping the grinding device of the embodiment. Further, since the object to be ground 3 is ground with the grindstone 5 after immersion in the fine bubble water 32, and after being ground the object to be ground 3, the object 3 is again immersed in the fine bubble water 32. It is possible to maintain sex.

  Also, for example, in the case where the object to be ground 3 is a semiconductor package, different from grinding of a conventional silicon wafer, for example, a process of simultaneously grinding different materials such as semiconductor, metal and resin may be required. However, since clogging easily occurs in the grinding wheel 5 when different materials are ground simultaneously by the grinding wheel 5, the grinding apparatus and the grinding method of the embodiment require a process for simultaneously grinding different materials. Etc. are considered to be particularly effective in grinding the object 3 to be ground.

  In addition, it is preferable that the fine bubble density in the fine bubble water 32 is 1000 pieces / ml or more (ml). In this case, the cleaning effect of the grindstone 5 can be improved. Further, the fine bubble density in the fine bubble water 32 can be set to 1,000,000 pieces / ml or more, and can be set to 1 billion pieces / ml or more. The fine bubble density can be measured, for example, with a cryotransmission electron microscope by ice embedding method.

  Further, as shown in a schematic enlarged cross-sectional view of FIG. 10, it is possible to immerse the grindstone 5 in the fine bubble water 32 while jetting the fine bubble water from the fine bubble water supply hole 31 in the direction of the arrow 51. .

  Further, as shown in the schematic plan view of FIG. 11, the jet of fine bubble water from the fine bubble water supply hole 31 is in the second direction 46 opposite to the first direction 45 which is the rotational direction of the grinding portion 11. It can also be done. In this case, since the pressure at the time of the collision of the fine bubble water 32 with the grindstone 5 can be improved, it can be considered that the cleaning effect by the immersion of the grindstone 5 by the fine bubble water 32 can be improved.

Example 1
First, as shown in FIG. 7, the fine bubble water supply portion attachment portion 12 a of the fine bubble water supply portion 12 of the grinding apparatus is fixed to the cover 21 surrounding the grinding portion 11, and the object to be ground 3 is mounted on the stage 2. installed. Here, as the object to be ground 3, an object to be ground provided with a sealing resin 3b made of a resin mixed with silica as a filler on the support member 3a was used.

  Next, the fine bubble water 32 is generated by the fine bubble water generator 14, and the fine bubble water is supplied to the fine bubble water container 12b through the fine bubble water supply hole 31 provided in the bottom 12e of the fine bubble water container 12b. did. As the fine bubble water generator 14, a water supply apparatus equipped with a fine bubble generation nozzle (product name: OKE-MB04FJA) manufactured by OK Engineering Co., Ltd. was used.

Next, shown in FIG. 4 by screws to the bottom surface 6a of the wheel mount 6 shown a grinding wheel 16 having a plurality of grinding wheel 5 to the annular base 1 5 are arranged at intervals as shown in FIG. 3 in FIG. 2 The grinding unit 11 was configured as attached.

  Thereafter, as shown in FIG. 7, while supplying pure water as the grinding fluid from the grinding fluid supply unit 4 to the grinding surface of the object to be ground 3, the grinding unit 11 is rotated in the first direction 45 about the shaft 43. The stage 2 on which the object to be ground 3 is placed is rotated about the axis 44 in the second direction 46 which is the opposite direction to the first direction 45. Thereby, with respect to the grindstone 5 of the grinding wheel 16, grinding of the object to be ground 3 in the grinding area 41 and immersion of the fine bubble water storage portion 12b in the non-grinding area 42 into the fine bubble water 32 are alternately performed. The Grinding of the object 3 to be ground was performed so as to grind at least a part of the sealing resin 3b so as to reduce the thickness of the object 3 to be ground. Further, during grinding of the object 3 to be ground, the fine bubble water 32 is discharged from above the region 23 other than the region 22 where the object 3 to be ground is disposed, through the fine bubble water discharger 12c at the end face of the fine bubble water supplier 12. did.

  The grinding conditions are as shown in Table 1 below. The column of “feed rate [μm / min]” in Table 1 means the distance per minute when the grinding unit 11 is advanced in the vertical direction to the stage 2 side during grinding of the object 3 to be ground. Further, the column of “feed amount [μm]” in Table 1 means the total distance in which the grinding unit 11 is advanced in the vertical direction toward the stage 2 during grinding of the object 3 to be ground. Further, in the column of “spark out [seconds]” in Table 1, the movement for advancing the grinding unit 11 in the vertical direction toward the stage 2 side is stopped in the grinding of the object to be ground 3 and the rotation of the grinding unit 11 and the stage 2 is maintained Means the time [seconds] of the condition. The column of “n number” in Table 1 means the number of samples. The fact that “n number” in Table 1 is “4” means that grinding was performed under the same conditions for four samples, and the average value of the measurement data of four samples is shown in Table 2 below. It is a numerical value.

As described above, the grinding wheel wear rate [%] of the grinding wheel 5 of Example 1 after grinding the object to be ground 3 under the conditions described in Table 1 and the surface roughness Ra of the grinding surface of the object to be ground 3 [μm ] Was measured. As a result, the abrasive wear rate of Example 1 is 19 . The surface roughness Ra was 0.18 8 μm.

The grinding wheel wear rate was calculated by the following equation (I).
Grinding wheel wear rate [%] = {100 × (wear amount of grinding wheel 5)} / (feed amount) ... (I)
Moreover, surface roughness Ra was computed by the method as described in JIS B0601: 2013 (ISO 4287: 1997).

Example 2
In the second embodiment, a fine bubble generation nozzle manufactured by Okamoto Machine Tool Mfg. Co., Ltd. is used instead of a water supply apparatus equipped with a fine bubble generation nozzle manufactured by OK Engineering Co., Ltd. as the fine bubble water generator 14 (product name: The object to be ground 3 was ground using the same grinding method and grinding conditions as in Example 1 except that a water feeder fitted with GRIND-BIX) was used.

Then, the grinding wheel wear rate [%] of the grinding wheel 5 of Example 2 after grinding the object to be ground 3 by the same method as in Example 1 and the surface roughness Ra [μm] of the grinding surface of the object to be ground 3 It was measured. As a result, the grinding wheel wear rate of Example 2 was 15.2 [%], and the surface roughness Ra was 0.1 47 [μm].

Comparative Example 1
In Comparative Example 1, the object to be ground 3 was ground in the same manner and under the same conditions as in Example 1 and Example 2 except that fine bubbles were not generated by the fine bubble water generator 14.

Then, the abrasive wear rate [%] of the grindstone 5 of the comparative example 1 after grinding the object to be ground 3 by the same method as in the embodiment 1 and the embodiment 2 and the surface roughness Ra of the grinding surface of the object 3 to be ground μm] was measured. As a result, the grinding wheel wear rate of Comparative Example 1 was 20.7 [%], and the surface roughness Ra was 0. It was 228 [μm].

<Summary>
In Table 2 below, the wear rate [%] of the grindstones 5 of Example 1 and Example 2 and Comparative Example 1 and the surface roughness Ra [μm] of the ground surface of the object to be ground 3 are the presence or absence of fine bubbles It is shown together with the type of fine bubble water generator 14, the feed amount [μm], and the feed rate [μm / min].

  As apparent from the results shown in Table 2, Example 1 and Example 2 in which the grinding of the object to be ground 3 in the grinding area 41 and the immersion in the fine bubble water 32 in the non-grinding area 42 were alternately performed. The grindstone 5 was able to greatly reduce the wear rate [%] of the grindstone 5 as compared to the grindstone 5 of Comparative Example 1 in which immersion in fine bubble water was not performed, and the surface of the ground surface of the object 3 to be ground The roughness Ra [μm] could also be reduced.

  Although the embodiments and examples have been described as described above, it is also planned from the beginning to appropriately combine the configurations of the above embodiments and examples.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all the modifications within the meaning and scope equivalent to the claims.

  The embodiments disclosed herein can be used for a grinding apparatus and a grinding method, and can be particularly effectively used for grinding an object to be ground such as a semiconductor package that requires a process for simultaneously grinding different materials. .

  DESCRIPTION OF SYMBOLS 1 base, 2 stages, 3 grinding object, 3a support member, 3b sealing resin, 4 grinding fluid supply part, 5 grindstone, 6 wheel mount, 6a bottom face, 7 spindle, 8 motor, 9 connection part, 10 pillar part, 11 grinding unit, 12 fine bubble water supply unit, 12a fine bubble water supply unit attachment unit, 12b fine bubble water storage unit, 12c fine bubble water discharge unit, 12d end wall, 12e bottom, 12f wall, 12g connection, 13 hose, 14 fine bubble water generator, 15 annular base, 16 grinding wheel, 21 cover, 22, 23 area, 31 fine bubble water supply hole, 32 fine bubble water, 41 grinding area, 42 non-grinding area, 43, 44 axis, 45 first direction, 46 second direction, 51 arrow.

Claims (8)

A grinding apparatus comprising a rotatable grinding portion in which a grinding wheel is arranged annularly, comprising:
The grinding wheel is disposed such that a grinding area for grinding the grinding object and a non-grinding area for not grinding the grinding object coexist while grinding the grinding object.
The grinding device further comprises
A fine bubble water generator, configured to produce fine bubble water,
A fine bubble water supply unit configured to be able to supply the fine bubble water to the grindstone in the non-grinding region ;
The fine bubble water supply unit, the houses fine bubble water the fine bubble water supplied from the generator, Ru is configured to immersing the grindstone of the non-ground region, grinding apparatus. The grinding apparatus further includes a base, and a stage disposed on the base and installed when the object to be ground is ground.
The fine bubble water supply unit includes a fine bubble water discharge unit configured to be able to discharge the fine bubble water,
The grinding apparatus according to claim 1, wherein the fine bubble water discharger is located above the base in a region other than the region corresponding to the installation location of the object to be ground. The grinding apparatus according to claim 1, further comprising a grinding fluid supply unit configured to supply grinding fluid to the grinding surface of the object to be ground. The object to be ground includes a support member and a sealing resin on the support member,
The grinding according to any one of claims 1 to 3 , wherein the grinding device is configured to grind at least a part of the sealing resin so as to reduce the thickness of the object to be ground. apparatus. A grinding method including the steps of rotating a grinding portion on which a grinding wheel is arranged annularly, and grinding an object to be ground by the grinding wheel,
The grinding wheel is disposed such that a grinding area for grinding the grinding object and a non-grinding area for not grinding the grinding object coexist while grinding the grinding object.
Producing fine bubble water by a fine bubble water generator and supplying it to a fine bubble water supply unit;
See containing and a step of supplying the fine-bubble water to the grindstone of the non-ground region,
Said step of supplying fine bubble water, step a including immersing the grindstone of the non-ground region in the fine bubble water, grinding method. A grinding apparatus used in the grinding method includes a base, and a stage disposed on the base and installed when the object to be ground is ground,
The grinding method according to claim 5 , further comprising the step of discharging the fine bubble water from above the base in a region other than the region corresponding to the installation position of the object to be ground. The grinding method according to claim 5 or 6 , further comprising: supplying a grinding fluid to a grinding surface of the object to be ground. The object to be ground includes a support member and a sealing resin on the support member,
The step of grinding the grinding target comprises a step of grinding at least a portion of said sealing resin so as to reduce the thickness of the grinding object to any one of claims 5 to claim 7 Grinding method described.

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