JP3854085B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus used for forming a semiconductor device, and more particularly to a processing apparatus capable of cleaning or etching a substrate without damaging a circuit formed on the surface of the substrate.
[0002]
[Prior art]
Conventionally, there has been a scrub cleaning apparatus as shown in FIG. 3 as a cleaning apparatus for cleaning a semiconductor substrate. This apparatus holds a semiconductor substrate W to be cleaned and rotates the spin chuck 40, a roll sponge 41 that rotates about an axis parallel to the surface of the substrate W, and a cleaning liquid on the surface to be cleaned of the substrate W. A cleaning liquid nozzle 42 is provided. The roll sponge 41 is rotated by the support driving unit 43 and cleaned while rubbing the surface of the substrate W. The spin chuck 40 rotates while supporting the outer periphery of the substrate W, and the rotational force is transmitted to the outer surface of the substrate W so that the substrate W rotates.
[0003]
[Problems to be solved by the invention]
According to the conventional method as described above, the roll sponge scrubs the entire surface of the substrate and the back surface. On the other hand, soft materials such as low dielectric constant films have begun to be used on the circuit formation surface of the substrate surface, or circuit miniaturization has progressed and the circuit has become very small. There was a possibility. On the other hand, the back surface of the substrate is subjected to vacuum chucking or electrostatic chucking in a semiconductor manufacturing process, and particles are fixed. It is desirable to remove such fixed particles by scrub cleaning.
[0004]
Therefore, an object of the present invention is to provide a substrate processing apparatus that can perform a process such as scrub cleaning on the front surface and the back surface of a substrate at the same time without damaging a circuit formed on the substrate.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a substrate processing apparatus according to a first aspect of the present invention is a rotating support that supports and rotates a disk-shaped substrate W having a front surface Wa and a back surface Wb, for example, as shown in FIG. 7; a first roll 1 slidably contacting the surface Wa while rotating around the first rotational axis AX1, and a second roll 2 slidably contacting the back surface Wb while rotating around the second rotational axis AX2. The second rotation axis AX2 is substantially parallel to the first rotation axis AX1, and the second roll 2 is provided so as to face the first roll 1 so as to sandwich the substrate W; At least one of the roll 1 and the second roll 2 has a length in the direction of the rotation axes AX1 and AX2 of the portion of the slidable contact so that only the outer peripheral portion of the substrate W is covered by both ends of the diameter of the substrate W. It is configured.
[0006]
Here, the substrate processing is, for example, cleaning of the substrate, but may be etching of the other substrate.
[0007]
If comprised in this way, since it is provided with a rotation support body, it can support and rotate a substrate, and since it is provided with a first roll that is in sliding contact with the front surface and a second roll that is in sliding contact with the back surface, The back surface can be processed at the same time , and at least one of the first roll and the second roll has a length in the rotation axis direction of the portion of the roll that comes into sliding contact with only the outer peripheral portion of the substrate. in which is configured to cover, for at least one surface of the substrate can be in addition an outer peripheral portion processed without sliding contact.
[0008]
Further, as described in claim 2, in the substrate processing apparatus according to claim 1, the other of the first roll 1 and the second roll 2 is the length in the rotation axis direction of the part of the roll that comes into sliding contact. Is configured to cover the diameter D of the substrate W. If comprised in this way, the whole other surface of a board | substrate can be processed.
[0009]
Further, as described in claim 3, and for example, as shown in FIG. 1, in the substrate processing apparatus according to claim 1 or 2, the one roll 1 is a pair of sub-rolls arranged in the rotation axis direction. 1a and 1b, each of the pair of sub-rolls is configured to be in sliding contact with the outer peripheral portion of the substrate W at both ends of the diameter D of the substrate W.
[0010]
Furthermore, as described in claim 4, the first roll 1 and the second roll 2 may be roll sponges.
[0011]
Further, as described in claim 5, in the substrate processing apparatus according to any one of claims 1 to 4, the rotary support 7 includes a sponge member 18 that contacts the side surface of the substrate W. Also good.
[0012]
If comprised in this way, since a rotation support body is provided with the sponge member which contacts the side surface of a board | substrate, a side surface can also be processed at the time of the process of the surface of a board | substrate, and a back surface.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol or a similar code | symbol is attached | subjected to the mutually same or equivalent member, and the overlapping description is abbreviate | omitted.
[0014]
1A and 1B are a front view and a perspective view, respectively, of a scrub cleaning apparatus according to an embodiment of the present invention.
[0015]
The scrub cleaning apparatus includes a spin chuck 7 that is a rotation support body that supports and rotates a peripheral portion of a wafer W as a disk-shaped substrate having a front surface Wa and a back surface Wb. The wafer W is supported by the spin chuck 7 and rotates with the rotation.
[0016]
The spin chuck 7 includes a plurality of (six in the present embodiment) spindles 7a to 7f that rotate about a rotation axis in the vertical direction. The spindles 7a to 7f are arranged on a certain circumference along the outer periphery of the wafer W. The spindles 7a to 7f are provided at substantially equal intervals around the wafer W.
[0017]
A top 15 (see FIG. 2) for holding the outer periphery of the wafer W is provided at the upper end of the spindles 7a to 7f. There is a step between the spindles 7a to 7f and the piece 15, and the wafer W is placed on a step formed at the upper end of the spindles 7a to 7f. The wafer W is rotated by being transmitted to the outer peripheral surface. The configuration of the piece 15 will be described in more detail later.
[0018]
A first roll 1 that rotates about a first rotation axis AX1 is provided above the wafer W supported and rotated by the spin chuck 7 in the vertical direction. The first rotation axis AX1 is parallel to the surface Wa of the wafer W. The roll 1 has a rotating shaft 1s extending above the wafer W, and sub-rolls 1a and 1b attached to both ends of the rotating shaft 1s. The sub-rolls 1a and 1b have lengths L1 and L2, respectively, in the direction of the rotation axis AX1, and are configured to contact both ends of the diameter D of the wafer W to be cleaned and not to contact the center of the wafer W. Yes. In the present embodiment, L1 = L2 = about 20 mm. The sub-rolls 1a and 1b are attached to the rotation shaft 1s so that the centers of the sub-rolls 1a and 1b in the direction of the rotation axis AX1 substantially coincide with the outer periphery of the wafer W.
[0019]
The sub-roll 1a is configured such that a sponge is sandwiched between disc-shaped sponge stoppers 1c and 1d attached to a rotating shaft 1s. The diameters of the sponge stoppers 1c and 1d are configured to be smaller than the outer diameter of the sponge in the attached state. The same applies to the sub-roll 1b. The rotary shaft 1s has an internal rinse outlet 10 for supplying a rinse liquid to the sponge portions of the sub-rolls 1a and 1b, and an internal communication hole (not shown) leading to an internal rinse supply port 8 described later is machined. Yes. The rinse liquid supplied from the internal rinse discharge port 10 is configured to penetrate the porous sponge and reach the wafer W.
[0020]
A shaft support 3 is provided on one end of the rotating shaft 1s, outside the sub-roll 1b, and rotatably supports the rotating shaft 1s. The shaft support 3 is provided with an internal rinse supply port 8 to which a rinse supply pipe (not shown) is connected.
[0021]
A motor 5 for rotating the rotation shaft 1s is connected to the other end of the rotation shaft 1s and outside the sub-roll 1a. The motor 5 is integrally connected to the shaft support 3 by a bracket (not shown). The motor 5 and the shaft support 3 are configured to be vertically movable in a vertical direction (in the direction of arrow A in the figure) by an unillustrated vertical driving device.
[0022]
In the roll 1 configured as described above, the sub-rolls 1a and 1b are in sliding contact with the surface Wa of the wafer W while being rotated about the rotation axis AX1 by the motor 5. At this time, the motor 5 and the shaft support 3 move up and down in the direction of arrow A so that the sub-rolls 1a and 1b are just in sliding contact with the wafer W. Since the spin chuck 7 includes the six spindles 7a to 7f, the wafer W is not completely circular, and can be rotated and supported without any problem even if an orientation flat that is a notch is formed, for example. .
[0023]
On the other hand, a second roll 2 that rotates around a second rotation axis AX2 parallel to the first rotation axis AX1 is provided below the wafer W that is supported and rotated by the spin chuck 7 in the vertical direction. The second roll is provided to face the first roll so as to sandwich the wafer W in cooperation with the first roll. The roll 2 has a rotating shaft 2s extending below the wafer W and a roll body 2a attached over almost the entire length of the rotating shaft 2s. The roll body 2a is formed to have a length L3 that covers the diameter D of the wafer W to be cleaned. That is, there is a relationship L3 ≧ D. Therefore, the roll body 2a is configured to contact the entire back surface Wb of the wafer W.
[0024]
The rotary shaft 2s is provided with an internal rinse outlet 11 for supplying a rinsing liquid to a roll body 2a formed of sponge, and an internal communication hole (not shown) leading to an internal rinse supply port 9 described later is machined. ing. The rinse liquid supplied from the internal rinse discharge port 11 penetrates the porous sponge and reaches the wafer W in the same manner as the roll 1.
[0025]
A shaft support 4 is provided on one end of the rotating shaft 2s, on the same side as the shaft support 3 of the first roll, and rotatably supports the rotating shaft 2s. As with the shaft support 3, the shaft support 4 is configured to be movable up and down in the vertical direction (the direction of arrow B in the figure) by a vertical drive device (not shown). The shaft support 4 is provided with an internal rinse supply port 9, to which a rinse supply pipe (not shown) is connected.
[0026]
A motor 6 for rotating the rotary shaft 2 s is connected to the other end of the rotary shaft 2 s and the same side as the first roll motor 5. The motor 6 is integrally connected to the shaft support 4 by a bracket (not shown).
[0027]
In the roll 2 configured as described above, the roll body 2a is in sliding contact with the back surface Wb of the wafer W while being rotated about the rotation axis AX2 by the motor 6. At this time, the motor 6 and the shaft support 4 are moved up and down in the direction of the arrow B so that the roll body 2a is in sliding contact with the wafer W just like the first roll.
[0028]
A cleaning liquid nozzle 13 is provided in the vertical direction above the wafer W support surface of the spin chuck 7 with the mouth facing the surface Wa of the wafer W, and the mouth is directed to the back surface Wb of the wafer W below the vertical direction. A cleaning liquid nozzle 14 is provided. The cleaning liquid nozzles 13 and 14 supply ultrapure water as a cleaning liquid to the front surface Wa and the back surface Wb of the wafer W, respectively. Accordingly, the cleaning liquid is supplied to the wafer W from the nozzles 13 and 14 and the rinse discharge ports 10 and 11.
[0029]
The piece 15 of the present embodiment will be described in detail with reference to the side view of FIG. Here, the spindle 7a will be described, but the other spindles 7b to 7f are also formed in the same structure. The upper end portion of the spindle 7a is formed flat so that the wafer W can be placed thereon. On the plane, a piece shaft 17 that shares the rotation axis of the spindle 7a (the piece is a structure common to the respective spindles, so it is not shown as 18a but is simply 18). The same is also formed protruding. The piece shaft 17 is formed longer than the thickness of the wafer W to be cleaned. Further, a disc-shaped sponge stopper 16 is provided at the upper end of the piece shaft 17. A cylindrical side sponge 18 is sandwiched between the flat surface at the tip of the spindle 7 a and the sponge stopper 16. A piece 15 includes a sponge stopper 16, a piece shaft 17, and a side sponge 18.
[0030]
The wafer W is placed on the plane of the upper ends of the spindles 7a to 7f having such a structure. Next, when the spindles 7a to 7f are slightly moved inward (toward the wafer W), the wafer W bites into the side sponge 18 as shown in FIG. When the spindles 7a to 7f (and the piece 15) rotate in such a state, the wafer W rotates accordingly.
[0031]
In the cleaning apparatus of the present embodiment, the wafer W is placed on the spin chuck 7 with the surface Wa on which the circuit is formed facing upward in the vertical direction. The sub-rolls 1a and 1b of the first roll 1 are configured such that the length of the portion slidably contacting the wafer W in the direction of the rotation axis AX1 covers the outer peripheral portion of the wafer W without covering the central portion of the wafer W. Therefore, the roll can clean the peripheral portion of the front surface Wa and the back surface Wb of the wafer W on which the circuit is not formed without scrubbing the circuit portion, and the side surface of the wafer W is cleaned by the side sponge 18. The
[0032]
In the present embodiment, the first roll 1 has a structure including a pair of sub-rolls, and the second roll has a structure that covers the entire length of the wafer W. Conversely, the first roll has a full-length cover type. The second roll may be a sub-roll type. However, at this time, it is preferable to clean the wafer surface on which the circuit is formed on the second roll.
[0033]
A method for cleaning a wafer with the cleaning apparatus having the structure described above will be described. The present invention is particularly useful when, for example, cleaning an etched portion of a wafer obtained by etching the back surface, side surface, and peripheral portion of the front surface after CVD. In addition, a soft material such as a low dielectric constant film may be attached to the wafer, which is useful for cleaning the back surface of such a wafer.
[0034]
First, in the preliminary cleaning step, it is desirable to hold the wafer W horizontally by a cleaning device (not shown) and spray a cleaning liquid such as ultrapure water from the nozzle onto the wafer surface to wash away particles on the surface of the semiconductor wafer W. At this time, the wafer W may be rotated, and as a method of spraying ultrapure water onto the wafer surface, high pressure ultrapure water may be sprayed from a nozzle, or ultrapure water having cavitation is sprayed. Alternatively, ultrapure water to which ultrasonic vibration energy is applied may be sprayed, or a combination thereof may be used.
[0035]
In the next cleaning step, the cleaning apparatus according to the embodiment of the present invention described above is used. That is, the wafer W is transferred to the main cleaning apparatus and placed on the spin chuck 7. Next, the side surface of the wafer W is bitten into the side sponge 18.
[0036]
Next, rotation of the spindles 7a to 7f is started. That is, the rotation of the wafer W is started. Subsequently, the front and back surface roll sponge (roll brush) is rotated, and the rotating roll sponge is brought into contact with the wafer W by vertical movement.
[0037]
In the scrub cleaning apparatus configured as described above, the spindles 7a to 7f rotate the wafer W by pressing and rotating the piece 15 against the peripheral edge of the wafer W. In the figure, two of the six pieces 15 are rotated. A force may be applied to the wafer W, and the other pieces may act as a bearing that receives the rotation of the wafer W. However, the number of pieces to which the rotational force is applied may be selected as appropriate, and the rotational force may be applied to all the pieces 15.
[0038]
As shown in the perspective view of FIG. 1B, the spindle 7a rotates in the clockwise direction (in the direction of arrow R1 in the figure) as viewed from above, so that the wafer W is counterclockwise (in the direction of arrow R2 in the figure). Rotate. The first roll 1 for cleaning the front surface Wa of the wafer rotates in the clockwise direction (in the direction of arrow R3 in the figure) when viewed from the direction opposite to the shaft support 3, and the second roll for cleaning the back surface Wb. 2 rotates counterclockwise (arrow R4 direction in the figure).
[0039]
In this apparatus, the peripheral portion of the wafer surface Wa is cleaned by adjusting the width of the roll sponges of the surface sub-rolls 1a and 1b and by adjusting the mounting position on the pair of sub-rolls 1a and 1b rotating shaft 1s. The width can be controlled.
[0040]
While rotating the wafer W, a small amount of cleaning liquid (pure water or chemical liquid) is supplied from the inside of the roll sponge (brush), and the wafer W is cleaned by including the cleaning liquid in the sponge. Further, the cleaning liquid may be supplied to the wafer W from the nozzles 13 and 14 for cleaning. At this time, if pure water is supplied from the nozzle 13 to the circuit formation surface, the circuit can be protected.
[0041]
When cleaning is completed, rolls 1 and 2 are retracted.
Thereafter, the rotation of the wafer W is stopped and transferred to the outside of the cleaning apparatus by a robot hand (not shown).
[0042]
In the cleaning apparatus of the present embodiment, since the first roll 1 and the second roll 2 are provided facing the front and back surfaces of the wafer W, the wafer W is pushed from both sides, The deformation of the wafer W due to the pressing can be suppressed.
[0043]
For example, PVA (polyvinyl alcohol) is suitable as a material for the roll sponge. It is preferable to use PVAt (polyvinyl acetal) produced by condensing aldehydes with PVA as a raw material, and in particular, PVF (polyvinyl formal). This material is excellent in hydrophilicity, has water absorption and water retention due to fine continuous pores, does not damage the object to be cleaned, and does not cause uneven water absorption following the uneven surface. In addition, a material that has chemical resistance such as PPS and PTFE and that has no metal elution and is made into an unemployed cloth is useful for strong dirt, for example, a material that is fixed by applying heat.
[0044]
Although the width of the sub-rolls 1a and 1b is about 20 mm, it may be appropriately determined depending on the size of the wafer W to be processed and the size of the circuit forming surface (or the width of the peripheral portion where no circuit is formed). However, typically, it is preferably 20 mm or less.
[0045]
In the above embodiment, the first roll has been described as including a pair of sub-rolls 1a and 1b. However, the present invention is not limited to this, and the first roll may include only one sub-roll 1a. Even in this case, the peripheral portion can be cleaned without sliding on the circuit on the surface Wa of the wafer. In the second roll, L3 ≧ D, but not limited to this, L3 may be configured to be smaller than the diameter D of the wafer and larger than the radius thereof. In particular, when there is only one sub-roll 1a, the second roll is preferably opposed to the sub-roll 1a so as to cover the radius of the wafer.
[0046]
In the above embodiments, the cleaning apparatus has been described. However, an etching solution may be used instead of the cleaning solution, and the scrub etching apparatus as a substrate processing apparatus may be configured. Also at this time, as described above, pure water is supplied from the nozzle 13 to the surface of the substrate, and etching is performed while protecting the circuit surface from the etching solution, so that the circuit formed on the surface of the substrate is not damaged. The peripheral part, the side part, and the back face can be etched to remove unnecessary deposits such as copper. By rinsing a known etching solution with this apparatus, the amount of the etching chemical used could be reduced to half or less compared to the conventional similar apparatus. Moreover, the etching width of the peripheral part of the substrate surface could be adjusted by the width of the side sponge or the surface sponge.
[0047]
【The invention's effect】
As described above, according to the present invention, since the rotation support body is provided, the substrate can be supported and rotated, and the first roll slidably contacting the front surface and the second roll slidably contacting the back surface are provided. The front surface and the back surface of the substrate can be processed at the same time , and at least one of the first roll and the second roll has a length in the rotation axis direction of the portion of the roll in sliding contact with only the outer peripheral portion of the substrate. Since it is configured to cover at both ends of the diameter of the substrate, it is possible to provide a substrate processing apparatus that can process at least one surface of the substrate without sliding contact other than the outer sliding portion. .
[Brief description of the drawings]
FIG. 1 is a front view and a perspective view of a substrate cleaning apparatus according to an embodiment of the present invention.
FIG. 2 is a partial side view for explaining a tip portion and a piece of a spindle of a spin chuck used in the cleaning apparatus of FIG.
FIG. 3 is a perspective view showing a conventional scrub cleaning apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 1st roll 2 2nd roll 3, 4 axis | shaft support body 5, 6 Motor 7 Spin chuck 15 pieces

Claims (5)

A rotating support that supports and rotates a disk-shaped substrate having a front surface and a back surface;
A first roll in sliding contact with the surface while rotating about a first rotation axis;
A second roll slidably contacting the back surface while rotating around a second rotation axis, wherein the second rotation axis is substantially parallel to the first rotation axis and sandwiches the substrate. A second roll provided opposite the first roll;
At least one of the first roll and the second roll is configured such that the length of the roll in the sliding contact portion in the rotation axis direction covers only the outer peripheral portion of the substrate at both ends of the diameter of the substrate. Was;
Substrate processing equipment. The other of the first roll and the second roll is configured such that the length of the roll in the sliding contact portion covers the diameter of the substrate.
The substrate processing apparatus according to claim 1. The one roll includes a pair of sub-rolls arranged in the rotation axis direction, and each of the pair of sub-rolls is configured to be in sliding contact with the outer peripheral portion of the substrate at both ends of the diameter of the substrate. Alternatively, the substrate processing apparatus according to claim 2. The substrate processing apparatus according to claim 1, wherein the first roll and the second roll are roll sponges. The substrate processing apparatus according to claim 1, wherein the rotary support includes a sponge member that contacts a side surface of the substrate.

Images