JP2004090128A - Semiconductor wafer grinder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the grinding surface of a semiconductor wafer from being contaminated by contamination in a grinding chamber during grinding and after grinding. <P>SOLUTION: In this semiconductor wafer grinder, freely opened and closed dust-proof covers 70, 80 covering an area of the grinding surface 11 of the semiconductor wafer 10 that does not face a grinding wheel 30 are provided in an enclosure 60, and the dust-proof covers 70, 80 are put in the closing state to form the grinding chamber 100. A jet nozzle 44 for jetting a fluid serving as a washing medium for giving a washing effect to the grinding surface 11 of the semiconductor wafer 10 is provided in the grinding chamber 100. After grinding, the dust-proof covers 70, 80 are opened to carry semiconductor wafer 10 out of the enclosure 60 by a conveying arm 7. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is directed to a semiconductor wafer grinding machine for single-side grinding of an ultra-thin disk-shaped semiconductor wafer, by handling the semiconductor wafer after grinding from a grinding chamber that is contaminated with shavings or contaminated water generated during the grinding operation. The present invention relates to a semiconductor wafer provided with a mechanism for preventing the processing surface and the suction surface of the semiconductor wafer from being stained when the semiconductor wafer is taken out and for maintaining the semiconductor wafer clean.
[0002]
[Prior art]
FIG. 6 is an explanatory view showing how the shavings 6 scatter together with the coolant 42 in a conventional semiconductor wafer grinding machine.
[0003]
FIG. 7A is an explanatory view showing a state in which contaminated water 49 including scattered shavings 6 drops from the ceiling 61 of the housing 60 onto the grinding surface 11 in the conventional semiconductor wafer grinding machine. FIG. 2B is a schematic diagram showing a state in which a new semiconductor wafer 10 is placed on the suction pad 1 while the shavings 6 and the like that have fallen onto the suction surface 2 of the suction pad 1 are attached.
[0004]
As shown in FIG. 6, a coolant supply device 40 is provided as an auxiliary device on the semiconductor wafer grinding machine, and the coolant supply device 40 drops a coolant 42 onto the grinding surface 11 via a liquid feed pipe 41. A semiconductor wafer 10 is mounted on a rotary table 20, held by vacuum suction, and rotates at about 100 revolutions per minute in the direction of arrow J.
[0005]
A cup-shaped grindstone 30 which is attached to a holder 32 supported by another grindstone axis Z which is vertically disposed at a position away from the rotation axis of the rotary table 20 by the length of the rotation radius and constitutes a grindstone is provided. In order to bring the disk surfaces of the rotary table 20 into partial surface contact with each other, the rotary table 20 is disposed in a positional relationship such that the grindstone 30 partially covers the disk surface.
[0006]
Then, a part of the grinding surface 11 of the semiconductor wafer 10 is slidably contacted with a part of the grinding surface 31 on the lower side of the grinding wheel 30 and is directly connected to a motor (not shown) via a shaft or from the motor via a belt. To rotate in the direction of arrow K.
[0007]
Further, the grinding wheel 30 is placed so that the grinding surface 11 and the grinding wheel surface 31 slide properly, and the semiconductor wafer 10 is intermittently placed, sucked, held and released on the rotary table 20 in accordance with the grinding process. Has a lifting mechanism (not shown) that can be raised and lowered in the Z-axis direction.
[0008]
That is, the distance between the table surface of the rotary table 20 and the grindstone surface 31 is greatly widened, the semiconductor wafer 10 is set on the table surface so as to be inserted, the gap is closed, and then grinding is performed by a predetermined cut. The rotation of each of the rotary table 20 and the grindstone 30 is appropriately controlled.
[0009]
Here, as shown in FIGS. 6 and 7, dust and shavings 6 falling on the grinding surface 11 and the suction surface 2 are not only silicon chips but also diamond, for example, having a roughness of 300 to 350. There are debris or the like in which grains are dropped from the grindstone surface 31. The shavings 6 including these are scattered in the air as dust, fouling the room, and further, the polluted water 49 mixed with the coolant 42 drops from the ceiling 61 of the housing 60 of the device. Note that the housing 60 is merely a virtual cube for convenience of explanation.
[0010]
At this time, as shown in FIG. 7B, the semiconductor wafer 10 carried into the housing 60 is placed on the rotary table 20 and is suction-held on the suction surface 2 by vacuum suction indicated by an arrow V. At this time, when the new semiconductor wafer 10 is placed on the suction pad 1 by biting the shavings 6 while the dust or the shavings 6 that have fallen on the suction surface 2 of the suction pad 1 adhere to the board surface flatness ( Total Thickness Variation (hereinafter abbreviated as “TTV”), which may cause wafer cracking or damage.
[0011]
In addition, when the semiconductor wafer 10 after the grinding process is taken out by handling or the like, if the ground surface 11 of the semiconductor wafer 10 is contaminated with the contaminated water 49 falling from the ceiling 61 of the housing 60, the semiconductor wafer 10 is absorbed. Similarly, a phenomenon in which the shavings 6 are bitten also occurs on the suction surface of the suction pad to be handled, thereby damaging the ground surface 11 of the semiconductor wafer 10 and causing a reduction in the suction force.
[0012]
[Problems to be solved by the invention]
In recent years, ultra-compact ICs built into high-speed processing personal computers equipped with semiconductor memories, IC chips, and large-capacity memories, etc. have become ultra-compact ICs. There are three management issues. The first is clean, the second is TTV, and the third is cooling. These three issues require highly strict management as the semiconductor wafer becomes extremely thin.
[0013]
In general, the demands for electronic devices, etc., which are the final applications of semiconductor wafers, are light, thin, short, small, and high-performance. . Regarding these three issues, namely, first, cleanliness, secondly, TTV, and thirdly, cooling, although they have different technical concepts, they may be solved by the same or similar technology.
[0014]
The present invention relates to a semiconductor wafer grinding machine that requires precise and stable quality, particularly, the grinding surface 11 during wafer replacement and the suction surface 2 of the suction pad 1, the grinding surface 11 during grinding, and the semiconductor wafer in the vicinity thereof. In order to keep the entire surface 10 clean, the shavings 6 such as cutting chips generated by the grinding process are washed and removed, the TTV is also maintained in a predetermined range, and the cooling is also ensured, so that the mirror finish is achieved. It is an object of the present invention to provide a semiconductor wafer grinding machine capable of maintaining quality.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 provides a housing (60) having a loading port (62) for a semiconductor wafer (10), and a semiconductor provided in the housing (60) and loaded. A suction surface (2) for sucking and holding the wafer (10) and a ground surface (11) of the semiconductor wafer (10) provided in the housing (60) and sucked and held on the suction surface (2). And a grindstone (30) rotatably supported with a grindstone surface (31) facing the grindstone surface (31). Arc-shaped notches (72) and (82) are provided along the outer circumference of the whetstone (30), and the whetstone (30) is connected to the grinding surface (11) through the notches (72) and (82). A grinding surface (11) of the semiconductor wafer (10), which is capable of facing sliding contact. Openable dustproof cover for covering an exposed portion (70) comprises a (80), the dustproof cover (70), characterized in that the grinding chamber (100) is formed in a closed (80).
[0016]
According to the first aspect, the shavings (6) generated on the grinding surface (11) during the grinding process are not rolled up in the air, and dust and the like floating in the factory are on the grinding surface (11). The dust-proof covers (70) and (80) can be shielded so as not to adhere even if dropped.
[0017]
After the grinding, the dustproof covers (70) and (80) are opened, and the dustproof covers (70) and (80) can be retracted from above the semiconductor wafer (10). , (80) does not fall off the shavings (6) or the contaminated water (49) and contaminate the semiconductor wafer (10), and drops on the ceiling (61) of the housing (60). Since the semiconductor wafer (10) is not contaminated, the semiconductor wafer (10) can be carried out of the housing (60) in a clean state. Further, the suction surface (2) after the semiconductor wafer has been carried out can also be kept clean.
[0018]
Further, the invention according to claim 2 includes an injection nozzle (44) for ejecting a fluid serving as a cleaning medium capable of imparting a cleaning effect to at least the grinding surface (11) in the grinding chamber (100). Therefore, during the grinding process, the grinding surface (11) of the semiconductor wafer (10) can always be cleaned and cooled, and high-precision processing can be performed. In addition, the cleaning and cooling can be efficiently performed only in the grinding chamber (100). It is possible to keep the inside of the factory clean without diffusing the fluid to the outside of the grinding chamber (100).
[0019]
According to the third aspect of the present invention, the dustproof covers (70) and (80) are provided with the jet nozzles (75) and (85) on the surface facing the semiconductor wafer (10), so In addition, clean maintenance and cooling can be performed efficiently. Further, since the distance from the spray nozzles (75), (85) to the grinding surface (11) can be made small, the dust-proof covers (70), (80) do not become bulky, and the whole apparatus can be made small and light.
[0020]
The invention according to claim 4 is characterized in that the dustproof covers (70) and (80) have an opening area on the suction surface (2) so that the semiconductor wafer (10) can be attached and detached and replaced. Since a hinge opening / closing type or sliding opening / closing mechanism that exposes the surface (11) is provided, it can be used for mass production.
[0021]
That is, in the operation of continuously repeating the attachment / detachment / replacement of the semiconductor wafer (10) as a work in accordance with the progress of the grinding operation of the semiconductor wafer (10) for mass production, the dustproof cover (70) is used. , (80) are opened to expose the ground surface (11), the semiconductor wafer (10) can be detached and replaced through an opening having an area sufficient to detachably replace the semiconductor wafer (10) as a work. . Therefore, clean and smooth maintenance and cooling can be performed smoothly and reliably, and mass production can be supported.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Throughout the drawings, the same effects are denoted by the same reference numerals to avoid repetition of description, but the same effects may be shown in different shapes depending on the cross-sectional cuts and the like.
[0023]
FIG. 1 is a longitudinal sectional view of a semiconductor wafer grinding machine according to an embodiment of the present invention, in which (a) shows a state in which a hinge door 70 and a slide cover 80 provided as dustproof covers are closed, and (b) shows a dustproof cover. A state where the provided 70 and the slide cover 80 are opened is shown.
[0024]
On the side wall of the case 60, a carry-in port 62 into which the transfer arm 7 for carrying in and out the semiconductor wafer 10 is inserted is opened, and a frame body 63 is integrally erected on a base 65 thereof. A hinge door 70 provided as a dustproof cover and a slide cover 80 are provided inside the housing 60, and a grinding chamber 100 that covers the suction surface 2 and the grindstone 30 in a closed state is formed.
[0025]
FIG. 2 is a perspective view of a main part of the semiconductor wafer grinding machine in a state where a hinge door 70 and a slide cover 80 provided as dustproof covers are opened in directions of arrows M and N, respectively, inside the housing 60 of FIG. These dustproof covers are provided with a hinge opening / closing type or a sliding type opening / closing mechanism that has an opening area on the suction surface 2 that allows the semiconductor wafer 10 to be detachably exchanged and that exposes the grinding surface 11.
[0026]
FIG. 3 is a perspective view of an essential part showing a state where the hinge door 70 and the slide cover 80 shown in FIG. 2 are closed in the directions of arrows S and T.
As shown in FIGS. 1 to 3, the hinge door 70 is pivotally attached to a frame 63 integrated with the housing 60 by a hinge 71, and the slide cover 80 is slidable in the horizontal direction with respect to the rotary table 20. Guide 81 supports. Then, they are opened and closed by the cylinders 76 and 86, respectively.
[0027]
A substantially half-moon-shaped notch 72 is provided at a part of the door end of the hinged door 70, and a small gap is provided between the notch 72 and the outer peripheral surface 33 of the grindstone 30 so as to fit when closed. Combine. This gap may be minimized so that the outer peripheral surface 33 does not come into contact with the end surface 73 when the hinge door 70 is opened and closed and closed.
[0028]
On the other hand, a part of the butted portion of the slide cover 80 is provided with a substantially half-moon-shaped notch 82, and an end surface 83 of the notch 82 is provided with a slight gap so as not to make contact with the outer peripheral surface 33 of the grindstone 30. And fit when closed.
Further, as shown in FIG. 1, a portion of the grinding surface 11 off the grindstone 30 is washed obliquely from above so that the shavings 6 attached to the grinding surface 11 of the semiconductor wafer 10 are efficiently cleaned and gradually removed. An injection nozzle 44 that injects pure water serving as a medium is disposed at an injection angle that increases the cleaning efficiency.
[0029]
That is, as shown in FIGS. 1A and 3, the well-known single-side grinding is performed with the hinge door 70 and the slide cover 80 closed. The shavings 6 generated at this time do not scatter from the grinding chamber 100 to the outside. At this time, the high-pressure water supplied from the direction of the arrow P is sprayed from obliquely upward by the spray nozzle 44, so that it will adhere to the grinding surface 11. Is efficiently washed and gradually removed. Depending on the type of the grindstone 30 and the single-side grinding process, the momentum such as the angle at which pure water is injected and the water pressure are adjusted.
[0030]
The “fluid serving as a cleaning medium” in the claims may be a liquid or a gas, but in the present embodiment, pure water is used as the cleaning medium.
[0031]
The operation will now be described.
As shown in FIGS. 1B and 2, after opening the hinge door 70 and the slide cover 80, the semiconductor wafer 10 is handled on the rotary table 20 for detachment and replacement. The opening and closing operations of the hinge door 70 and the slide cover 80 are performed by the cylinders 76 and 86. Handling is performed by the transfer arm 7 having the suction pad 1a. The grindstone 30 and the holder 32 are appropriately moved up and down by a lifting mechanism (not shown) that can move up and down in the axial direction.
[0032]
Also, as shown in FIGS. 1A and 3, the exposed portion of the grinding surface 11 of the semiconductor wafer 10 placed on the rotary table 20 is covered with the hinge door 70 and the slide cover 80, and then the single-side grinding is started. I do. After that, when the one-side grinding is completed, the hinge door 70 and the slide cover 80 are opened to expose the ground surface 11 that has been covered. Then, by repeating a series of operations such as handling for detaching and replacing the semiconductor wafer 10 on the rotary table 20 again, it is possible to cope with mass production.
[0033]
The injection nozzle 44 shown in FIGS. 1A and 3 has an integral structure with the hinge door 70 or the slide cover 80 by using a pipe or the like embedded therein if the hinge door 70 or the slide cover 80 has a thick structure. It may be.
[0034]
FIGS. 4 and 5 use a plurality of injection nozzles 75 and 85 instead of the injection nozzles 44 shown in FIGS. 1A and 3, and attach them to the surface of the hinge door 70 or the slide cover 80 by using the semiconductor wafer 10. An example in which the grinding surface 11 is embedded or directly mounted at a position facing a portion of the grinding surface 11 that is separated from the grinding stone 30 is shown. It can also be mounted via a plurality of pipes not shown. By doing so, pure water can be simultaneously or selectively injected from the plurality of injection nozzles 75 and 85, so that the entire surface of the grinding surface 11 can be uniformly washed and cooled.
[0035]
Further, on the end faces 73, 83 of the notches 72, 82, a plurality of spray nozzles 74, 84 directed toward the outer peripheral face 33 of the grindstone 30 facing the end faces 73, 83 are arranged at equal intervals. The jet nozzles 74 and 84 jet, for example, air to wash the shavings 6 generated due to the single-side grinding of the grindstone 30. However, the air is actually injected after the hinge door 70 and the slide cover 80 are closed as shown in FIG.
[0036]
Note that the present invention can be variously improved within the scope of the technical idea, and various embodiments other than the above-described embodiment are conceivable. In these hinge doors, the injection nozzles 44, 74, 75, 84, and 85 clean the grinding surface 11 and the grindstone 30 by injecting pure water or air, and together with the cleaning effect, do not scatter the shavings 6 around. When a cover similar to 70 and the slide cover 80 is provided, it naturally belongs to the present invention.
[0037]
【The invention's effect】
Since the present invention has been configured as described above, in a semiconductor wafer grinding machine required to be precise and stable quality, when the wafer is replaced during the grinding process or after the grinding process, the ground surface and the entire semiconductor wafer around the same are removed. Thus, a semiconductor wafer grinder can be provided which can maintain cleanliness and thereby maintain the quality of mirror finish.
[0038]
According to the first aspect of the present invention, shavings generated on the ground surface during the grinding process are not rolled up in the air, and dust and the like drifting in the factory are prevented from adhering even if dropped on the ground surface. , Can be shielded by dustproof cover.
[0039]
After grinding, the dust-proof cover can be opened and the dust-proof cover can be evacuated from above the semiconductor wafer.Therefore, shavings and contaminated water adhering to the dust-proof cover may fall and contaminate the semiconductor wafer. In addition, the semiconductor wafer can be carried out of the housing in a clean state because the ceiling of the housing does not have dripping dirt. Further, the suction surface after the semiconductor wafer has been carried out can also be kept clean.
[0040]
According to the second aspect of the present invention, the grinding surface of the semiconductor wafer can be constantly cleaned and cooled during the grinding process, high-precision processing can be performed, and cleaning and cooling can be efficiently performed only in the grinding chamber. In addition, the inside of the factory can be kept clean without diffusing the fluid to the outside of the grinding room.
[0041]
According to the third aspect of the invention, it is possible to reliably and efficiently maintain and cool the cleaning. Further, since the distance from the spray nozzle to the grinding surface can be made small, the dustproof cover does not become bulky and the whole apparatus can be made small and lightweight.
[0042]
Further, according to the invention of claim 4, it is possible to cope with mass production.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a semiconductor wafer grinding machine according to an embodiment of the present invention, in which (a) shows a state where a dust cover is closed, and (b) shows a state where the dust cover is opened.
FIG. 2 is a perspective view showing a state in which a dust cover inside a housing is opened in the semiconductor wafer grinding machine of FIG. 1;
FIG. 3 is a perspective view showing a state in which a dust cover is closed in FIG.
FIG. 4 is a perspective view showing a modified embodiment of FIG. 2, showing a state in which a dust cover inside a housing is opened.
FIG. 5 is a perspective view showing a state in which a dust cover is closed in FIG.
FIG. 6 is an explanatory view showing how chips and the like are scattered together with a coolant in a conventional semiconductor wafer grinding machine.
FIG. 7A is an explanatory view showing a state in which contaminated water including scattered shavings and the like is dropped on a grinding surface in a conventional semiconductor wafer grinding machine, and FIG. FIG. 4 is a schematic diagram showing a state in which a new semiconductor wafer is placed on a suction pad while falling shavings and the like are attached.
[Explanation of symbols]
1, 1a suction pad 2 suction surface 6 shavings 7 transfer arm 10 semiconductor wafer 11 grinding surface 20 rotary table 30 grindstone 31 grindstone surface 32 holder 33 outer peripheral surface 40 coolant supply device 41 liquid supply pipe 42 coolant 44, 74, 75, 84 , 85 Injection nozzle 46, J, K, M, N, S, T, V Arrow 49 Polluted water 60 Housing 61 Ceiling 62 Carrying entrance 63 Frame 65 Base 70 Hinge door 71 Hinge 72, 82 Notch 73, 83 End face 76 , 86 Cylinder 80 Slide cover 81 Guide 100 Grinding chamber

Claims (4)

A housing (60) having a loading port (62) for the semiconductor wafer (10);
An adsorption surface (2) provided in the housing (60) for adsorbing and holding the loaded semiconductor wafer (10);
A grindstone surface (31) faces a ground surface (11) of a semiconductor wafer (10) provided in the housing (60) and held by suction on the suction surface (2) and is rotatably supported. And a grinding wheel (30),
In the housing (60), arc-shaped notches (72) and (82) are provided along the outer circumference of the grinding wheel (30) at the grinding wheel height position during grinding,
The grindstone (30) can be brought into sliding contact with the grinding surface (11) through the notches (72) and (82), and can be opened and closed to cover an exposed portion of the grinding surface (11) of the semiconductor wafer (10). Equipped with dustproof covers (70) and (80)
A semiconductor wafer grinding machine wherein a grinding chamber (100) is formed with the dustproof covers (70) and (80) closed. 2. The nozzle according to claim 1, further comprising: a jet nozzle for jetting a fluid serving as a cleaning medium capable of imparting a cleaning effect to at least the grinding surface in the grinding chamber. The semiconductor wafer grinding machine as described in the above. The semiconductor wafer according to claim 2, wherein the dust-proof covers (70), (80) are provided with the spray nozzles (75), (85) on a surface facing the semiconductor wafer (10). Grinder. The dustproof covers (70) and (80) have a hinge-opening / closing type in which the suction surface (2) has an opening area that allows the semiconductor wafer (10) to be attached and detached and exchanged to expose the grinding surface (11). 4. The semiconductor wafer grinding machine according to claim 1, further comprising a slide-type opening / closing mechanism.

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