JP4257816B2 - Wafer surface treatment equipment with waste liquid recovery mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wafer surface processing apparatus with a waste liquid recovery mechanism that can effectively separate and recover each waste liquid according to the type of the processing liquid or the cleaning liquid when processing the wafer surface with the processing liquid or the cleaning liquid. .
[0002]
[Related technologies]
In addition to the etching process to remove the damaged layer after backgrinding, the wafer surface in the device manufacturing process is coated with a developer solution on the wafer, and the developer solution is applied to the wafer surface exposed to the circuit pattern. For example, development processing of a wafer in which a semiconductor circuit is baked on the formed wafer, cleaning of the wafer surface, and the like can be performed.
[0003]
The apparatus used for the wafer surface treatment includes a wafer rotation holding device for chucking and rotating the wafer, a treatment liquid supply means for supplying a necessary treatment liquid (chemical solution) to the upper surface of the chucked wafer, and a cleaning liquid for the upper surface of the wafer. The cleaning liquid supply means and the like are used (for example, JP-A-8-88168).
[0004]
For example, the conventional etching for removing the damaged layer after the backgrinding may be performed once using a mixed acid (for example, hydrofluoric acid + nitric acid), and the treatment as disclosed in the above publication. A liquid (for example, a mixed acid) and a cleaning liquid may be recovered.
[0005]
However, at present, there is a need for surface modification after etching as described above, and it is normal to perform etching for surface modification once or a plurality of times after the first etching described above. As described above, if a plurality of surface treatments are performed, it takes a long time, and a new problem arises that the production efficiency is lowered. In addition, since a plurality of processing liquids (chemical liquids) are used, considering the recovery of the waste liquid, an apparatus that recovers two types of used waste liquid, that is, one type of processing liquid and a cleaning liquid as described above, is sufficient. First, a need has arisen for an apparatus that can recover three or more types of waste liquids.
[0006]
On the other hand, when etching or cleaning is performed on a very thin wafer having a thickness of 100 μm or less in recent years, one-side processing is required. Such a form makes it difficult to keep the rotation, and a new type of rotation holding means is desired.
[0007]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and according to the types of treatment liquid and cleaning liquid, each of the waste liquids, in particular, three or more types of waste liquids can be separated and recovered continuously and effectively. Rotation of wafers that can improve efficiency, and can rotate and hold very thin wafers of 100 μm or less only by contact with the outer periphery, and can also be cleaned by ultrasonic jet nozzles and brushes. An object of the present invention is to provide a wafer surface treatment apparatus with a waste liquid recovery mechanism provided with a holding device.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, a wafer surface treatment apparatus with a waste liquid recovery mechanism of the present invention, a wafer surface treatment apparatus for treating a wafer surface with a treatment liquid or a cleaning liquid, and rotating and holding the wafer to be surface-treated. And a waste liquid recovery mechanism provided so as to be movable up and down around the wafer rotation holding device, the waste liquid recovery mechanism One or a plurality of intermediate annular waste liquid recovery bowls that can be moved up and down with respect to the outer annular waste liquid recovery bowl, and an inner side that can be moved up and down with respect to the intermediate annular waste liquid recovery bowl An annular waste liquid recovery tank, Depending on the type of treatment liquid and cleaning liquid Above Multiple annular waste liquid recovery tanks Move up and down It is characterized in that it is used properly and each waste liquid is separated and recovered. By continuously raising and lowering the annular waste liquid recovery tank, the processing liquid and the cleaning liquid used for the surface treatment of the wafer can be continuously recovered, and the production efficiency can be improved.
[0009]
If three annular waste liquid recovery tanks are provided, there is an advantage that three types of waste liquid can be recovered.
[0010]
As the wafer rotation holding device, a rotating disk having a medium flow path formed on the upper surface, a through hole formed in the center of the rotating disk, and a plurality of holes provided on the upper surface of the rotating disk A wafer receiving portion, and a wafer is placed above the rotating disc via the wafer receiving portion with an interval therebetween, and when the rotating disc is rotated, the medium in the medium flow path is , And is discharged outward by centrifugal force due to rotation, thereby causing a reduced pressure state to appear in the medium flow path, and sucked from the lower surface side of the rotating disk through the through hole by the suction force of the reduced pressure state. The medium is supplied to the upper surface of the rotating disk and continuously discharged outward through the medium flow path. Thus, as long as the rotating disk rotates, the medium flow path is depressurized. The wafer is sucked downward by the suction force in the reduced pressure state. Preferably it has a structure which is adapted to rotate held by the wafer receiving portion.
[0011]
Even if a thin wafer having a thickness of about 100 μm or less is naturally warped, if it is placed and rotated as it is on the new wafer rotation holding device used in the present invention, it is centrifuged by rotation. There is an advantage that the warp of the wafer can be eliminated by the force and the wafer can be rotated and held without any trouble.
[0012]
The novel wafer rotation holding device used in the present invention further includes a medium forcible supply means for forcibly supplying the medium to the through hole from the lower surface side of the rotation disk, and the rotation disk while maintaining the reduced pressure state. It is preferable to forcibly supply the medium to the through hole from the lower surface side of the substrate. By adopting such a configuration, there is an advantage that it is possible to prevent the chemical liquid supplied to the wafer upper surface side for processing the wafer upper surface from flowing around the wafer lower surface side.
[0013]
It is preferable that the upper surface of the rotating disk is provided with a blade plate in a radial, spiral or spiral shape, and the medium flow path is formed between the blade plate facing the upper surface of the rotating disk and the lower surface of the wafer. It is.
[0014]
A rotating shaft having a hollow portion communicating with the through-hole in the axial direction is suspended at the center of the lower surface of the rotating disk, and when the rotating shaft and the rotating disk are rotated, the hollow portion of the rotating shaft It is also possible to supply the medium sucked from the lower end opening to the upper surface of the rotating disk through the hollow portion and the through hole.
[0015]
According to the thickness of the wafer, if the pressure reducing means is further provided to adjust the pressure reducing state of the medium flow path by adjusting the degree of opening of the hollow portion attached to an appropriate position of the rotating shaft. Since the depressurized state can be set freely, there is no accident such as deformation of the wafer due to excessive suction force.
[0016]
The wafer receiving portion can be constituted by a lower guide pin that receives the lower surface of the wafer and an outer guide pin that receives the outer surface of the wafer. In addition, the wafer receiving portion may be installed anywhere as long as it does not interfere with the receiving function as long as it is the upper surface of the rotating disk, but if it is provided on the upper surface of the vane plate, it is possible to effectively use the upper surface space of the rotating disk There is.
[0017]
A baffle plate is provided above the through hole formed in the center of the rotating disk, and the medium supplied to the upper surface of the rotating disk is guided to the blade plate by the baffle plate through the through hole. With this configuration, even if impurities are mixed in the medium, the medium will not be sprayed directly on the lower surface of the wafer, so it is possible to prevent accidents such as contamination by impurities, etc. There is an advantage that it is possible to prevent the upward blowing of the air.
[0018]
If an orientation flat receiving portion for receiving an orientation flat (orientation flat) portion or a notch receiving portion for receiving a notch portion is provided on the upper surface of the rotating disc, the wafer is locked to the upper surface of the rotating disc, so that both are always together. Will rotate. Therefore, even if a chemical solution or the like is poured onto the upper surface of the wafer while the wafer is rotating and a force in the direction opposite to the rotation direction is applied to the wafer, the wafer always rotates with the rotating disk. There is an advantage that no rotational deviation occurs, and there is no problem caused by the rotational deviation between the two described later.
[0019]
As the medium, a gas and / or a liquid, that is, a gas alone, for example, air, or a liquid alone, for example, pure water, a chemical solution, or the like can be mixed and used.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. Needless to say, various modifications can be made without departing from the technical idea of the present invention.
[0021]
FIG. 1 is a schematic cross-sectional side view of a wafer surface treatment apparatus with a waste liquid recovery mechanism according to the present invention, showing a state when a wafer is loaded or unloaded. FIG. 2 is a cross-sectional side schematic explanatory view showing the state in which the entire waste liquid recovery mechanism is lifted from the state of FIG. 1 to use the inner waste liquid recovery tank. FIG. 3 is a cross-sectional side schematic explanatory view showing the state in which only the inner waste liquid recovery basket is lowered from the state of FIG. 2 and the intermediate waste liquid recovery tank is used. FIG. 4 is a cross-sectional side schematic explanatory view showing the state in which only the intermediate waste liquid recovery tank is lowered from the state of FIG. 3 and the outer waste liquid recovery tank is used.
[0022]
1 to 4, S is a wafer surface treatment apparatus with a waste liquid recovery mechanism of the present invention, an annular waste liquid recovery mechanism 50 having a hollow portion H at the center, and a wafer rotation provided inside the hollow portion H. Holding device 10. The wafer rotation holding device 10 includes a wafer holding portion 10a and a rotating shaft 20 that rotatably supports the wafer holding portion 10a. The waste liquid recovery mechanism 50 has an annular outer slope member 52 that is inclined outward, and an outer square tube portion 54 that is formed by bending the distal end portion of the outer slope member 52 inward. Inside the outer slope member 52, there are provided an intermediate slope member 56 that is inclined in the same manner as the outer slope member 52, and an intermediate rectangular tube portion 58 that is formed by bending the tip of the intermediate slope member 56 inward. ing. Inside the intermediate slope member 56, there are provided an inner slope member 60 that is inclined in the same manner as the intermediate slope member 56, and an inner square tube portion 62 that is formed by bending the tip of the intermediate slope member 56 inward. ing.
[0023]
The outer slope member 52 and the outer rectangular tube portion 54 can move up and down, and therefore, the entire waste liquid recovery mechanism 50 is arranged to be movable up and down with respect to the wafer rotation holding device 10. The intermediate slope member 56 and the intermediate square tube portion 58 are movable up and down with respect to the outer slope member 52 and the outer square tube portion 54, and the outer surface of the intermediate slope member 56 is in contact with the inner surface of the outer slope member 52. The outer surface of the outer wall 58a of the intermediate rectangular tube portion 58 is in contact with the outer surface of the inner wall 54b of the outer rectangular tube portion 54.
[0024]
The inner slope member 60 and the inner square tube portion 62 are movable up and down with respect to the intermediate slope member 56 and the intermediate square tube portion 58, and the outer surface of the inner slope member 60 is in contact with the inner surface of the intermediate slope member 56. The outer surface of the outer wall 62a of the inner rectangular tube portion 62 is in contact with the outer surface of the inner wall 58b of the intermediate rectangular tube portion 58.
[0025]
An outer annular waste liquid collecting basket 64 is formed by the outer slope member 52, the outer square tube portion 54, the intermediate slope member 56 and a part of the outer wall 58 a of the intermediate square tube portion 58. An intermediate annular waste liquid collecting basin 66 is formed by the intermediate slope member 56, the intermediate square tube portion 58, the inner slope member 60 and a part of the outer wall 62 a of the inner square tube portion 62. An inner annular waste liquid collecting rod 68 is formed by the inner slope member 60 and the inner rectangular tube portion 62.
[0026]
Therefore, the waste liquid recovery mechanism 50 includes a plurality (three in the illustrated example) of annular waste liquid recovery rods 64, 66, and 68, and the waste liquid recovery rods 64, 66, and 68 are attached to be movable up and down. The bottom surfaces of the waste liquid collection tanks 64, 66, and 68 are inclined in one direction, and waste liquid collection pipes 70, 72, and 74 are provided at the lowermost part of the inclination. 76 is a processing liquid pouring means for pouring a chemical liquid or a cleaning liquid, and a plurality of (three in the illustrated example) pouring pipes 76a, 76b, 76c are suspended depending on the type of the chemical liquid to be poured. .
[0027]
With the configuration described above, the operation of the wafer surface treatment apparatus S with a waste liquid recovery mechanism of the present invention will be described by taking as an example the case of performing mixed acid etching, dilute hydrofluoric acid etching, and rinse cleaning. First, as shown in FIG. 1, the waste liquid recovery mechanism 50 is positioned so as to be slightly lower than the holding position of the wafer W of the wafer rotation holding device 10 by the uppermost edge portion of the inner end of the outer inclined member 52. In this state, the wafer W is held by the wafer rotation holding device 10.
[0028]
Next, in order to perform the mixed acid etching, as shown in FIG. 2, the entire waste liquid recovery mechanism 50 is raised so that the upper end edge of the inner wall 62 b of the inner rectangular tube portion 62 is held by the wafer rotation holding device 10. It moves so that it may be located in the vicinity. In this state, the wafer W is rotated and the processing liquid pouring means 76 is moved to the pouring position, and mixed acid is poured into the upper surface of the rotating wafer W from the mixed acid pouring pipe 76a to perform mixed acid etching. At this time, the mixed acid poured onto the upper surface of the wafer W is scattered outward by the centrifugal force of the rotating wafer W, but this scattered mixed acid is accommodated in the inner waste liquid collecting tank 68 through the opening 68a. Subsequently, it flows down according to the inclination of the bottom surface of the inner waste liquid collection tank 68 and is collected through the mixed acid waste liquid collection pipe 74.
[0029]
In order to perform dilute hydrofluoric acid etching, as shown in FIG. 3, the inner slope member 60 and the inner rectangular tube portion 62 are lowered from the state of FIG. 2, and the upper edge of the inner slope member 60 is positioned at the wafer rotation holding device 10. The wafer W is moved so as to be positioned in the vicinity of the holding position of the wafer W. In this state, the wafer W is rotated, and diluted hydrofluoric acid is injected from the diluted hydrofluoric acid injection pipe 76b of the processing liquid injection means 76 to perform diluted hydrofluoric acid etching. At this time, the diluted hydrofluoric acid added to the upper surface of the wafer W is scattered outward by the centrifugal force of the rotating wafer W. The scattered diluted hydrofluoric acid is contained in the intermediate waste liquid recovery tank 66 through the opening 66a. Then, it flows down according to the inclination of the bottom surface of the intermediate waste liquid recovery tank 66 and is recovered through the waste liquid recovery pipe 72 for dilute hydrofluoric acid.
[0030]
In order to perform the rinse cleaning, as shown in FIG. 4, the intermediate slope member 56 and the intermediate rectangular tube portion 58 are lowered from the state of FIG. 3, and the upper edge of the intermediate slope member 56 is the wafer of the wafer rotation holding device 10. It moves so that it may be located in the vicinity of the holding position of W. In this state, the wafer W is rotated and pure water is poured from the pure water pouring pipe 76c of the processing liquid pouring means 76 to perform rinsing cleaning. At this time, the pure water poured on the upper surface of the wafer W is scattered outward by the centrifugal force of the rotating wafer W, and the scattered pure water enters the outer waste liquid recovery tank 64 through the opening 64a. Then, it flows down according to the inclination of the bottom surface of the outer waste liquid collection tank 64 and is collected through the waste liquid collection pipe 70 for rinsing liquid.
[0031]
After the mixed acid etching, diluted hydrofluoric acid etching and rinsing cleaning are finished, the intermediate slope member 56, the intermediate square tube portion 58, the inner slope member 60 and the inner square tube portion 62 are raised, and the entire waste liquid recovery mechanism 50 is Descent Then, as shown in FIG. 1, the waste liquid recovery mechanism 50 is positioned slightly below the holding position of the wafer W of the wafer rotation holding device 10 from the uppermost edge of the inner end of the outer slope member 52. In this state, the wafer W is removed from the wafer rotation holding device 10.
[0032]
As the wafer rotation holding device 10 described above, a chuck means for holding a wafer in a known rotation state may be used. However, it is preferable to use a new wafer rotation holding device 10 as described below. The structure will be described below with reference to FIGS.
[0033]
FIG. 5 is a perspective explanatory view showing an example of a novel wafer rotation holding device used in the present invention. FIG. 6 is a perspective explanatory view showing a state in which the wafer is rotated and held by the wafer rotation holding device of FIG. 7 is a top view showing another example of the blade, and FIG. 8 is a top view showing another example of the blade.
[0034]
In the figure, reference numeral 10 denotes a novel wafer rotation holding device used in the present invention, which has a rotating disk 12. A through hole 14 is formed in the center of the rotating disk 12. On the upper surface of the rotating disk 12, a plurality of blade plates 16 (16 in the illustrated example) are erected in a radial pattern at a predetermined interval.
[0035]
A wafer receiving portion 18 that receives the outer peripheral portion of the wafer W is provided at the outer end portion of the upper surface of the plurality of blade plates 16. The shape of the wafer receiving portion 18 is not particularly limited as long as it can receive the outer peripheral portion of the wafer W, but in the illustrated example, it is a receiving step portion. The wafer receiving portion 18 is not necessarily provided on the blade plate 16 and can be directly provided on the upper surface of the rotating disk 12 as long as there is no hindrance. Further, the number of the wafer receiving portions 18 may be the number that can be rotated and held even when the wafer W is rotated, for example, three or more, but in the illustrated example, four wafer receiving portions 18 are provided at symmetrical positions. showed that.
[0036]
Reference numeral 20 denotes a rotating shaft that is suspended from the center of the lower surface of the rotating disk 12, and a hollow portion 22 that communicates with the through hole 14 is formed in the axial direction. The hollow portion 22 is opened at the lower end of the rotary shaft 20 and is a lower end opening 24.
[0037]
At the lower end portion of the rotary shaft 20, a decompression adjustment means 26, in the illustrated example, a decompression adjustment valve is attached. The decompression adjusting means 26 can control the amount of air flowing through the hollow portion 22 by adjusting the degree of opening of the hollow portion 22 of the rotary shaft 20. In the illustrated example, the case where the decompression adjusting means 26 is provided at the lower end portion of the rotary shaft 20 is shown, but it is only necessary to be able to adjust the opening degree of the hollow portion 22, and it is not always necessary to provide the lower end portion, It can be installed at an appropriate position such as the upper part.
[0038]
A pulley 28 is provided below the rotary shaft 20 and is connected to a motor pulley 32 of the motor 30 via a pulley belt 34. When the motor 30 is driven, the motor pulley 32 rotates, and the rotation is transmitted to the pulley 28 via the pulley belt 34 so that the rotating shaft 20 rotates.
[0039]
The operation will be described with the configuration described above. In the wafer rotation holding device 10 used in the present invention, as the medium, for example, a gas such as air or a liquid such as pure water or a chemical solution may be mixed, but the case where air is used as the medium is also used. This will be described as an example.
[0040]
First, as shown in FIG. 6, the wafer W is spaced above the upper surface of the rotating disk 12 via the wafer receiving portion 18, that is, at an interval above the upper surface of the blade plate 16. Is placed. Further, the degree of opening of the hollow portion 22 of the rotary shaft 20 is adjusted by the pressure reducing means 26 so as to be in an optimum pressure reducing state corresponding to the thickness of the wafer W. If the opening of the hollow portion 22 is widened, the degree of pressure reduction becomes small, and if the opening is narrowed, the degree of pressure reduction becomes large.
[0041]
This pressure reduction state can be adjusted by adjusting the rotational speed of the rotating disk 12 in addition to the opening degree of the hollow portion 22 described above. If the rotation of the rotating disk 12 is accelerated, the degree of decompression becomes large, and if the rotation is slowed, the degree of decompression becomes small.
[0042]
Further, if necessary, a medium, for example, air is supplied to the upper surface of the rotating disk 12 by a medium (air) supply means (not shown), and the amount of supply medium (air) is adjusted to adjust the degree of pressure reduction. can do. If the amount of replenishment medium (air) is large, the degree of decompression is small, and if the amount of replenishment medium (air) is small, the degree of decompression is large.
[0043]
When the motor 30 is driven in this state, the rotation of the motor 30 is transmitted to the rotating shaft 20 via the motor pulley 32, the pulley belt 34, and the pulley 28, and the rotating disk 12 connected to the rotating shaft 20 rotates. When the rotating disk 12 rotates, the medium (air) on the upper surface of the rotating disk 12 is discharged outward by centrifugal force due to the rotation, that is, a pair of opposed blade plates 16, 16 on the upper surface of the rotating disk 12. The medium (air) A on the rotating disk 12 is discharged outwardly through a plurality of medium (air) flow paths 36 formed between the wafer W and the lower surface of the wafer W.
[0044]
As the medium (air) A is discharged outward, the inside of the medium (air) flow path 36 is in a reduced pressure state. The medium (air) A sucked from the lower end opening 24 of the hollow portion 22 of the rotating shaft 20 by the suction force in the reduced pressure state is supplied to the upper surface of the rotating disk 12 through the hollow portion 22 and the through hole 14. Then, the air is continuously exhausted outwardly through the medium (air) flow path 36, and the inside of the medium (air) flow path 36 is continuously maintained in a reduced pressure state.
[0045]
As long as the rotating disk 12 continues to rotate, the inside of the medium (air) flow path 36 is in a reduced pressure state. Due to the suction force of the medium (air) flow path 36 in the reduced pressure state, the outer periphery of the wafer W is fixed and held by the wafer receiving portion 18. At this time, the back surface of the wafer W is located above the upper surface of the blade plate 16 and does not come into contact with the upper surface of the blade plate 16.
[0046]
If the suction force due to the reduced pressure state is too strong, there is a case where the central portion hangs down in the case of a thin wafer W (for example, a thickness of 0.1 mm or less). However, in the present invention, since the degree of opening of the hollow portion 22 of the rotating shaft 20 can be freely controlled by the pressure reducing adjustment means 26, in the case of a thin wafer W, the opening of the hollow portion 22 is widened to reduce the degree of pressure reduction. Thus, it is possible to weaken the suction force so that the wafer does not hang down and is held and fixed to the wafer receiving portion 18 by rotation.
[0047]
In many cases, the warp naturally occurs on a thin wafer having a thickness of about 100 μm or less, but even in such a case, the wafer is held on the wafer rotation holding device of the present invention in a state where the warp is generated. If it is placed and rotated, the wafer warp is eliminated by the centrifugal force caused by the rotation, so that it can be held without any trouble. There is an advantage that labor is eliminated. Since the rotation of the wafer does not correct the warpage of the wafer, it goes without saying that if the rotation is stopped, the warpage will be restored.
[0048]
In the example shown in FIG. 5 and FIG. 6, the case where the blade plate 16 is erected radially on the upper surface of the rotating disk 12 is shown, but the spiral shape as shown in FIG. 7 or the spiral shape as shown in FIG. It can also be provided in a shape. When the blade plate 16 is provided radially or spirally, it is necessary to provide a plurality of medium flow paths 36 using a plurality of blade plates 16, but when the blade plate 16 is provided in a spiral shape, the blade plate 16 is provided. Of course, a plurality of sheets can be used, but the same effect can be achieved even if one medium channel 36 is formed by one blade plate 16 as shown in FIG.
[0049]
In the illustrated example, the blade plate 16 is erected as a separate member on the upper surface of the rotating disk 12. However, the medium flow path 36 may be formed on the upper surface of the rotating disk 12 by the blade plate 16. For example, the blade plate 16 is integrally provided on the upper surface of the rotating disk 12 by leaving the portion of the medium flow path 36 in a groove shape and leaving the blade plate 16 in a raised state. Is also possible.
[0050]
The novel wafer rotating and holding apparatus used in the present invention can be variously modified in addition to the illustrated examples described above, and will be described below.
[0051]
FIG. 9 is a schematic cross-sectional side view showing another example of the novel wafer rotation holding device used in the present invention. FIG. 10 is an enlarged top view of the rotating disk of FIG. FIG. 11 is an enlarged view of a main part of the rotating disk of FIG. FIG. 12 is a partial cross-sectional explanatory view of FIG.
[0052]
5 to 6, the case where air is used as the medium A has been described. However, as described above, other media can be used. FIG. 9 shows a case where pure water mist obtained by mixing pure water and air is used as the medium A. In the mixing chamber 40, pure water supplied from the pure water tank 42 and separately supplied air are mixed to form pure water mist A composed of pure water and air, and supplied to the flow controller 26A via the conduit 44. The The pure water mist A whose flow rate has been adjusted by the flow rate adjuster 26A passes through the hollow portion 22 of the rotating shaft 20 and is introduced into the upper surface side of the rotating disk 12 as in the case of FIGS.
[0053]
Note that the air in FIG. 9 may be sucked by the suction force generated by the reduced pressure state formed in the medium flow path 36, but in this embodiment, medium forced supply such as a compressor or a motor is performed. The pure water mist A which is forcibly supplied to the mixing chamber 40 by the means 38 and thus mixed in the mixing chamber 40 is also influenced by the medium forcing supply means 38 through the conduit 44 and the hollow portion 22. The hole 14 is forcibly supplied. By adopting such a configuration, it is possible to prevent the chemical solution supplied to the wafer upper surface side for processing the wafer upper surface from entering the wafer lower surface side. This is performed by blowing the forcibly supplied medium A onto the lower surface of the wafer.
[0054]
In FIG. 9, reference numeral 46 denotes a baffle plate provided on the rotating disk 12 so as to be positioned above the through hole 14 formed at the center of the rotating disk 12. The medium (pure water mist) A supplied to the upper surface of the rotating disk 12 through the through hole 14 is guided by the baffle plate 46 toward the blade plate 16.
[0055]
By installing the baffle plate 46, even if impurities are mixed in the medium A, the medium A is not directly sprayed on the lower surface of the wafer W, so that an accident that the medium A is contaminated by impurities or the like is prevented. There is an advantage that the upward blowing of the medium A when W is broken is prevented.
[0056]
When pure water mist is used as the medium A, backside rinsing is simultaneously performed on the lower surface side of the wafer with pure water mist when etching is performed by supplying an etching solution to the upper surface side while rotating the wafer W. There is an advantage that can be.
[0057]
In the example of FIGS. 9 to 12, unlike the example shown in FIGS. 5 and 6, the wafer receiving portion 18 has lower guide pins 18a for receiving the lower surface of the wafer W as shown in FIGS. It comprises outer guide pins 18b that receive the outer surface of the wafer W. Since the configuration other than the above description is the same as the configuration of FIGS.
[0058]
As in the case of FIGS. 5 to 6, when the rotating disk 12 is rotated, the medium on the upper surface of the rotating disk 12 is exhausted outward by the centrifugal force due to the rotation, that is, through the through hole 14. The passed medium A is guided laterally through the lower surface of the baffle plate 46, and subsequently formed between the upper surface of the rotating disk 12, the pair of opposed blade plates 16, 16 and the lower surface of the wafer W. The medium A on the rotating disk 12 is discharged outward through the plurality of medium flow paths 36.
[0059]
Further, as described above, by forcibly supplying the medium A, the medium A is positively sprayed on the lower surface of the wafer, and a chemical solution such as an etching solution supplied to the upper surface of the wafer is prevented from flowing into the lower surface of the wafer. can do. Needless to say, the forced supply of the medium A can be performed regardless of the presence or absence of the baffle plate 46.
[0060]
In the novel wafer rotation holding device used in the present invention, when a chemical solution or the like is poured onto the upper surface of the wafer W in the rotation holding state, the wafer W is pulled in the direction opposite to the rotation direction of the rotation holding device 10 due to the viscosity of the chemical solution or the like. , A difference in rotation occurs between the rotation of the wafer W and the rotation of the rotation holding device 10 (the rotation of the wafer decreases) (FIG. 13). Generation of scratches due to increased contact friction, (2) Variation in processing conditions such as etching due to uneven rotation of wafer, and (3) Lower surface of wafer such as chemicals due to decrease in centrifugal force due to decrease in wafer rotation Problems such as an increase in wraparound may occur.
[0061]
In order to prevent such a problem from occurring, an orientation flat stopper pin FP (FIG. 14) that contacts the orientation flat (orientation flat) surface F of the wafer W and a notch stopper pin NP that contacts the notch portion N of the wafer W (FIG. 15). ) On the upper surface of the wafer W to prevent a difference in rotation between the rotation of the wafer W and the rotation of the rotation holding device 10, there is a problem due to the above-described rotational misalignment. It will never occur.
[0062]
Such a novel wafer rotation holding apparatus used in the present invention can be suitably applied to an apparatus that performs processing while rotating a wafer, such as a spin etching apparatus, a spin drying apparatus, and a spin coating apparatus.
[0063]
【The invention's effect】
As described above, according to the wafer surface processing apparatus of the present invention, each waste liquid, that is, a plurality of waste liquids, in particular, three or more types of waste liquids are continuously and effectively separated and recovered according to the types of the processing liquid and the cleaning liquid. Therefore, the production efficiency can be improved, and furthermore, a very thin wafer having a thickness of 100 μm or less can be rotated and held only by contact with its outer peripheral portion, and further cleaning by an ultrasonic jet nozzle or brush cleaning can be performed. The effect that it becomes possible is also achieved.
[0064]
In addition, by using the new wafer rotation holding device having the above-described configuration, a reduced pressure state appears on the upper surface of the rotating disk with a simple mechanism without the need for a vacuum source device, a pressurized air supply device, a gas supply device, or the like. The wafer can be rotated and held without contacting the back side of the wafer, and the degree of decompression can be adjusted easily. Even a thin wafer (thickness of 0.1 mm or less) can be rotated without deformation. The effect that it can be held can also be achieved.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional side view of a wafer surface treatment apparatus with a waste liquid recovery mechanism of the present invention.
2 is a schematic cross-sectional side view of the same, showing a state in which the entire waste liquid recovery mechanism is raised from the state of FIG. 1;
FIG. 3 is a schematic sectional side view of the same as above, showing a state in which only the inner waste liquid recovery tank is lowered from the state of FIG. 2;
4 is a cross-sectional side schematic explanatory view showing the state in which only the intermediate waste liquid recovery tank is lowered from the state of FIG. 3; FIG.
FIG. 5 is a perspective explanatory view showing one embodiment of a wafer rotation holding device used in the present invention.
6 is a perspective explanatory view showing a state in which the wafer is rotated and held by the wafer rotation holding device of FIG. 5; FIG.
FIG. 7 is a top view showing another example of a blade.
FIG. 8 is a top view showing another example of a blade.
FIG. 9 is a schematic cross-sectional side view showing another embodiment of the wafer rotation holding device used in the present invention.
10 is an enlarged top view of the rotating disk of FIG. 9;
FIG. 11 is an enlarged view of a main part of the rotating disk of FIG.
12 is a partial cross-sectional explanatory diagram of FIG. 11. FIG.
FIG. 13 is an upper surface explanatory view showing a state of occurrence of deviation between the rotation of the wafer and the rotation of the wafer rotation holding device when the chemical solution is poured onto the upper surface of the wafer rotated and held by the wafer rotation holding device.
FIG. 14 is an explanatory top view showing a state where the orientation flat surface of the wafer is locked to the orientation flat stopper pin standing on the rotating disk.
FIG. 15 is a top explanatory view showing a state in which a notch portion of a wafer is locked to a notch stopper pin standing on a rotating disk.
[Explanation of symbols]
10: Wafer rotation holding device, 12: Rotating disk, 14: Through hole, 16: Blade plate, 18: Wafer receiving portion, 18a: Lower guide pin, 18b: Outer guide pin, 20: Rotating shaft, 22: Hollow Part, 24: lower end opening part, 26: decompression adjusting means, 26A: flow rate regulator, 28: pulley, 30: motor, 32: motor pulley, 16, 16: vane plate, 34: pulley belt, 36: medium flow path, 38: medium forced supply means, 40: mixing chamber, 42: pure water tank, 44: conduit, 46: baffle plate, 50: waste liquid recovery mechanism, 52: outer slope member, 54: outer square tube portion, 56: intermediate slope member 58: Intermediate square tube part, 60: Inner slope member, 62: Inner square tube part, 64, 66, 68: Annular waste liquid recovery tank, 70, 72, 74: Waste liquid recovery pipe, 76: Treatment liquid injection means, 76a, 76b, 76c: pouring pad -Flops, A: media, FP: orientation flat receiving portion, NP: notch receiving portion, W: wafer.

Claims (13)

A wafer surface processing apparatus for processing a wafer surface with a processing liquid or a cleaning liquid, a wafer rotation holding apparatus for rotating and holding a wafer to be surface-treated, and a waste liquid recovery mechanism provided around the wafer rotation holding apparatus so as to be vertically movable And the waste liquid recovery mechanism includes an outer annular waste liquid recovery tank , one or a plurality of intermediate annular waste liquid recovery tanks that are vertically movable with respect to the outer annular waste liquid recovery tank, and the intermediate annular waste liquid recovery tank. and a inner annular waste liquid recovery trough which is vertically movable for, selectively used by vertically moving said plurality of annular waste liquid collecting trough on the type of the treatment liquid and washings were as each waste is separated and recovered A wafer surface treatment apparatus with a waste liquid recovery mechanism.   2. The wafer surface processing apparatus according to claim 1, wherein three annular waste liquid recovery tanks are provided.   The wafer rotation holding device includes a rotating disk having a medium flow path formed on an upper surface thereof, a through hole formed in a central portion of the rotating disk, and a plurality of wafers provided on the upper surface of the rotating disk. And when the wafer is placed above the rotating disk via the wafer receiving part with an interval therebetween, and the rotating disk is rotated, the medium in the medium flow path is It is discharged outward by centrifugal force due to rotation, thereby causing a reduced pressure state to appear in the medium flow path, and sucked from the lower surface side of the rotating disk through the through hole by the suction force of the reduced pressure state. A medium is supplied to the upper surface of the rotating disk and continuously discharged outward through the medium flow path. Thus, as long as the rotating disk is rotating, the medium flow path is in a reduced pressure state. And the wafer is sucked downward by the suction force in the reduced pressure state. Ha receiving wafer surface treatment apparatus according to claim 1 or 2, wherein it has to be rotated held by unit.   There is further provided a medium forcible supply means for forcibly supplying the medium to the through hole from the lower surface side of the rotating disk, and the medium is forcibly supplied to the through hole from the lower surface side of the rotating disk while maintaining the reduced pressure state. The wafer surface treatment apparatus according to claim 1, wherein the wafer surface treatment apparatus is configured as described above.   A vane plate is provided radially, spirally, or spirally on the upper surface of the rotating disc, and the medium flow path is formed between the vane plate facing the upper surface of the rotating disc and the lower surface of the wafer. The wafer surface treatment apparatus according to claim 3 or 4, characterized in that:   A rotating shaft having a hollow portion communicating with the through-hole in the axial direction is suspended at the center of the lower surface of the rotating disk, and when the rotating shaft and the rotating disk are rotated, the hollow portion of the rotating shaft The wafer surface according to claim 3, wherein the medium sucked from the lower end opening is supplied to the upper surface of the rotating disk through the hollow portion and the through hole. Processing equipment.   The pressure reducing adjustment means according to claim 6, further comprising a pressure reducing adjustment means attached to an appropriate position of the rotating shaft to adjust a pressure reducing state of the medium flow path by adjusting an opening degree of the hollow portion. Wafer surface treatment equipment.   8. The wafer surface processing apparatus according to claim 3, wherein the wafer receiving portion includes a lower guide pin that receives the lower surface of the wafer and an outer guide pin that receives the outer surface of the wafer.   The wafer surface processing apparatus according to claim 4, wherein the wafer receiving portion is provided on an upper surface of a blade plate.   A baffle plate is provided above the through-hole drilled in the center of the rotating disk, and the medium supplied to the upper surface of the rotating disk is guided to the blade plate by the baffle plate through the through-hole. The wafer surface treatment apparatus according to claim 3, wherein the wafer surface treatment apparatus is configured as described above.   The wafer rotation holding device according to any one of claims 3 to 10, wherein an orientation flat receiving portion for receiving an orientation flat portion is provided on an upper surface of the rotating disc.   11. The wafer rotation holding device according to claim 3, wherein a notch receiving portion for receiving a notch portion is provided on an upper surface of the rotating disk.   The wafer surface processing apparatus according to claim 3, wherein the medium is a gas and / or a liquid.