JP2004119716A - Mechanism and method of holding substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate holding apparatus and method which can reduce the wear of components and can stably hold a substrate. <P>SOLUTION: A wafer W is held on a substrate holding plane 11a of a spin base 11 via a water film 5 formed of pure water in a static state. The movement of the wafer W on the substrate holding plane 11a is regulated by regulation pins 25. The wafer W is held on the substrate holding plane 11a, with an active face facing downwards, and is supplied with an etchant E from the upper side. The etchant E runs around to a circumferential end face of the wafer W, reaching a peripheral part of the active face. A quantity of the etching E running around is controlled by a rotational speed of a spin chuck 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate holding mechanism and a substrate holding method applied to a substrate transfer hand for transferring a substrate, a processing chuck for holding a substrate during substrate processing, and the like. Substrates to be held include various substrates such as semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma display panels, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, and substrates for photomasks. It is.
[0002]
[Prior art]
In a manufacturing process of a semiconductor device, a metal thin film such as a copper thin film is formed on the entire surface of a semiconductor wafer (hereinafter, simply referred to as a “wafer”) and a peripheral end surface (and, in some cases, a back surface). In some cases, a process of removing unnecessary portions by etching is performed. For example, the copper thin film for forming the wiring only needs to be formed in the device forming region on the front surface of the wafer, and therefore, the peripheral portion of the front surface of the wafer (for example, a portion having a width of about 5 mm from the peripheral end of the wafer), the back surface, The copper thin film formed on the peripheral end surface becomes unnecessary. In addition, the copper or copper ions on the peripheral portion, the back surface, and the peripheral end surface contaminate the hand of the substrate transfer robot provided in the substrate processing apparatus, and the contamination is transferred to another substrate held by the hand. Causes the problem of metastasis.
[0003]
For the same reason, a process for removing metal contaminants (including metal ions) on the surface by etching a thin film (such as an oxide film or a nitride film) other than the metal film formed on the periphery of the substrate is required. May be done.
A substrate peripheral processing apparatus for selectively etching a thin film at a peripheral portion and a peripheral end portion of a wafer includes, for example, a spin chuck that rotates while holding the wafer horizontally, and a space on the wafer above the spin chuck. A limiting plate; and an etchant supply nozzle for supplying an etchant to the lower surface of the wafer. The etchant supplied to the lower surface of the wafer travels on the lower surface of the wafer due to centrifugal force, moves outward in the radial direction of rotation, travels along the peripheral end surface of the wafer, and wraps around the upper surface thereof. Etch unnecessary objects. At this time, the blocking plate is arranged close to the upper surface of the wafer, and an inert gas such as nitrogen gas is supplied between the blocking plate and the wafer.
[0004]
By appropriately adjusting the flow rate of the inert gas, the distance between the shut-off plate and the wafer, and the number of revolutions of the spin chuck, the amount of wraparound of the etching solution can be adjusted. 7 mm) can be selectively etched (so-called bevel etching).
In order to supply the etching liquid from the lower surface of the wafer, a mechanical chuck having a configuration in which a peripheral portion of the wafer is held by a plurality of holding pins is used as the spin chuck. However, if the pin is in constant contact with the same portion of the peripheral portion of the wafer, the process of the peripheral portion of the wafer cannot be performed in a portion that is shaded by the pin.
[0005]
Therefore, as disclosed in Patent Document 1 below, by temporarily relaxing or canceling the holding by the holding pins while rotating the spin chuck, the relative rotation between the spin chuck and the wafer is caused to occur, A configuration has been proposed in which a holding position by a holding pin is shifted.
[0006]
[Patent Document 1]
JP 2001-118824 A
[Patent Document 2]
JP-A-11-26540
[0007]
[Problems to be solved by the invention]
However, in the above-described configuration, when the wafer is relatively rotated with respect to the spin chuck, the pin and the peripheral end surface of the wafer rub against each other, so that there is a problem that the pin is worn.
Also, if the pinching of the wafer by the pin is released during the processing, the minute gap between the wafer and the blocking plate cannot be kept constant, thereby reducing the amount of the etchant spilling from the back surface of the wafer. It cannot be controlled accurately.
[0008]
Furthermore, since the configuration is such that nitrogen gas is continuously supplied to the upper surface of the wafer for the purpose of preventing splash of the etchant into the device formation region and for the purpose of controlling the flow of the etchant, the consumption of nitrogen gas is reduced. There is also a problem that there are many.
Therefore, an object of the present invention is to provide a substrate holding device and a substrate holding method that can reduce the problem of wear of components and stably hold a substrate.
It is another object of the present invention to provide a substrate holding mechanism and a substrate holding method capable of holding a substrate so that a peripheral portion of the substrate can be favorably processed.
[0009]
Still another object of the present invention is to provide a substrate holding mechanism and a substrate holding method which can stably hold a substrate throughout the processing of the substrate.
[0010]
Means for Solving the Problems and Effects of the Invention
According to the first aspect of the present invention, the substrate is held in a state in which the liquid is kept stationary and the liquid and one main surface of the substrate (W) are in close contact with each other. A substrate holding member (11, 40, 80) and a regulating member (25, 55, 83) for regulating movement of the substrate held by the substrate holding member (in particular, movement in a direction along the one main surface). A substrate holding mechanism comprising: It should be noted that the alphanumeric characters in parentheses indicate corresponding components and the like in embodiments described later. Hereinafter, the same applies in this section.
[0011]
More specifically, the substrate holding member tightly holds one main surface of the substrate by the action of atmospheric pressure or the like with a liquid film (5, 58) formed by a stationary liquid interposed therebetween. is there. That is, when one main surface of the substrate is brought into close contact with the substrate holding member with the liquid film interposed therebetween, the atmospheric pressure acting on the main surface of the substrate opposite to the one main surface (the reduced pressure atmosphere or the reduced pressure atmosphere in the processing chamber). (Including pressure from a pressurized atmosphere), the substrate is strongly held on the substrate holding member. The liquid film between the substrate and the substrate holding member is held by the action of the surface tension of the liquid film, and the liquid constituting the liquid film does not spill, so that the substrate is stably held on the substrate holding member. become.
[0012]
With such a configuration, the substrate is held on the substrate holding member, and the movement of the substrate (in particular, the movement in the direction along one main surface of the substrate; the parallel movement relative to the substrate holding member) is controlled by the regulating member. Since the substrate is regulated, the substrate can be reliably held. In addition, the regulating member may be configured to contact the peripheral end surface of the substrate without any gap and to sandwich the substrate, but it is not necessary to necessarily contact the peripheral end surface of the substrate all the time, as long as the substrate can be prevented from jumping out. Since it is good, it can be provided in a state having a minute interval with respect to the peripheral end surface of the substrate. Therefore, the substrate can be held in a state where the peripheral end surface of the substrate is not shaded by any member, so that good processing can be performed over the entire peripheral end surface of the substrate, and the substrate can be clamped. It is not always necessary to provide a complicated mechanism for opening and closing the pins during rotation of the substrate.
[0013]
Also, there is no need to change or release the holding position of the substrate by relaxing or releasing the holding by the holding pins. For example, when the regulating member is arranged in a state having a gap with respect to the peripheral end surface of the substrate, the regulating member may be opposed to the same position on the peripheral end surface of the substrate from beginning to end. In this case, it is possible to avoid or suppress the problem of wear of parts.
The “one main surface” of the substrate described above refers to at least one of the two surfaces of the substrate, and may be a surface of a substrate on which devices are formed (device formation surface), The surface on which the device is not formed on the opposite side (non-device formation surface) may be used.
[0014]
The invention according to claim 2 further comprises a liquid introduction means (15, 16, 17, 18) for introducing a liquid between the substrate holding member and the substrate. It is.
The liquid introducing means may further introduce liquid between the substrate and the substrate holding surface while the substrate is held on the substrate holding surface of the substrate holding member via the liquid. In this case, by introducing a liquid (a large amount of liquid) between the substrate and the substrate holding surface while the substrate is held on the substrate holding surface, the substrate can be brought into a floating state on the substrate holding surface. Thus, the holding of the substrate by the substrate holding member can be released. In this case, it is preferable that the liquid introduction means supplies the liquid from a liquid introduction port (15) formed in the substrate holding surface.
[0015]
Further, if the liquid is supplied onto the substrate holding surface by the liquid introducing means before the one main surface of the substrate is brought into contact with the substrate holding surface, the supplied liquid causes a liquid film between the substrate and the substrate holding surface. Can be formed. Alternatively, even if one main surface of the substrate is temporarily brought into contact with the substrate holding surface and then liquid is supplied onto the substrate holding surface by the liquid introducing means, the substrate and the substrate holding surface are similarly supplied by the supplied liquid. And a liquid film between them can be formed.
[0016]
The invention according to claim 3 further comprises gas introducing means (15, 16, 17, 19) for introducing gas between the substrate holding member and the substrate. It is a holding mechanism.
It is preferable that the gas introduction means supplies gas from a gas introduction port (15) formed in the substrate holding surface of the substrate holding member.
According to this configuration, in a state where the substrate is held on the substrate holding surface of the substrate holding member via the liquid, a gas is introduced between the substrate holding surface of the substrate holding member and the substrate, so that both surfaces of the substrate are held. Since the atmospheric pressure can be applied equally to the above, the holding of the substrate by the substrate holding member can be released.
[0017]
The invention according to claim 4 is provided so as to be able to advance and retreat with respect to the one main surface of the substrate held by the substrate holding member, and to advance toward the one main surface of the substrate, thereby allowing the substrate to move toward the one main surface. The substrate holding mechanism according to any one of claims 1 to 3, further comprising a substrate holding release member (35) separated from the substrate holding member.
According to this configuration, the substrate can be peeled from the substrate holding member by the substrate holding release member, and the holding can be reliably released. In particular, by combining with the liquid introducing means of claim 2 or the gas introducing means of claim 3, it is possible to release the substrate more reliably.
[0018]
According to a fifth aspect of the present invention, the size of the liquid surface between the substrate holding member and the substrate is smaller than the size of the substrate. Processing device.
More specifically, for example, when the substrate to be held is a circular substrate such as a semiconductor wafer, the diameter of the liquid surface may be smaller than the diameter of the substrate.
According to this configuration, on the one main surface of the substrate to be held, since the peripheral portion is not in contact with the liquid surface, the peripheral portion can be treated with a processing fluid (especially, an etching solution). . That is, for example, while a device forming surface such as a semiconductor wafer is kept in contact with the liquid, the peripheral portion can be processed.
[0019]
In addition, at least a part (for example, a peripheral edge) of the substrate has a portion that is not in contact with the liquid surface, and thus has an advantage that the substrate can be easily separated from the substrate holding member.
The substrate holding mechanism can be applied to a substrate transfer hand (80) that holds and transfers a substrate. In this case, since the substrate can be stably held while restricting the movement of the substrate on the hand, it is possible to suppress the conveyance failure. Further, even if the substrate is displaced on the hand due to acceleration and deceleration of the hand during the transfer of the substrate, since direct friction between the substrate and the hand hardly occurs, generation of particles can be prevented.
[0020]
Further, as described in claim 7, the substrate holding mechanism holds the processing chuck (1, 1) for holding the substrate during a period in which the substrate is being processed (particularly during processing with a processing liquid or a processing gas). 50).
The invention according to claim 8 is characterized in that the substrate holding mechanism includes a substrate rotating mechanism (13, 53) for rotating the substrate (for example, around a rotation axis passing through the center thereof). This is a substrate holding mechanism.
[0021]
Since the close contact holding of the substrate to the substrate holding member by the action of the atmospheric pressure is sufficiently strong, even if the substrate is rotated, the substrate does not fall off the substrate holding member. That is, the substrate holding mechanism of the present invention can be applied to a spin chuck that rotates while holding a substrate.
According to a ninth aspect of the present invention, the regulating member is switchable between a clamping state in which the substrate is clamped and a release state in which the clamping of the substrate is released. It is a holding mechanism.
[0022]
It is preferable that the substrate holding mechanism further includes a control means (30) for controlling the regulating member to the sandwiched state when the rotation of the substrate is accelerated or decelerated, for example. When the substrate holding member is rotating at a constant speed, the relative rotation between the substrate holding member and the substrate hardly occurs, but when the rotation of the substrate is accelerated or decelerated, the substrate is held by the inertia force acting on the substrate. Attempts to rotate relative to the member may cause unstable holding of the substrate to the substrate holding member. Therefore, in such a case, if the regulating member is brought into contact with the peripheral end surface of the substrate so as to sandwich the substrate, it is possible to reliably prevent the substrate from jumping out.
[0023]
10. The substrate holding mechanism according to claim 10, wherein the substrate holding mechanism is used in a substrate processing apparatus that processes a peripheral portion of a substrate. May be used.
That is, for example, a substrate holding mechanism as described above, and processing fluid supply means (2, 71) for supplying a processing fluid (processing liquid or processing gas) to a peripheral portion of the substrate held by the substrate holding mechanism. Can be configured.
[0024]
According to the substrate holding mechanism of the present invention, when the processing fluid is supplied to the substrate and the substrate surface is processed, the substrate can be held without sandwiching the substrate. Can be performed well.
The processing fluid supply means may supply processing fluid (mainly liquid) to another main surface different from the one main surface facing the substrate holding surface of the substrate holding member. In this case, due to the viscosity of the processing fluid, the processing fluid wraps around the peripheral end surface of the substrate, reaches the peripheral portion of the one main surface, and performs processing on this region.
[0025]
In this case, it is preferable that the one main surface of the substrate is a device formation surface. Then, it is possible to effectively prevent the processing fluid from entering the device forming surface and processing the device forming surface.
According to the eleventh aspect of the present invention, the substrate is held in a state where the liquid is kept stationary by the substrate holding member (11, 40, 80), and the substrate is brought into close contact with one main surface of the substrate (W). And a movement regulating step of regulating movement of the substrate held by the substrate holding member.
[0026]
According to the present invention, the same effect as that of the first aspect can be obtained.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus to which a substrate holding mechanism according to an embodiment of the present invention is applied. This substrate processing apparatus removes unnecessary substances (thin films, particles, metal ions, etc.) on the periphery of a device forming surface, which is one main surface of a semiconductor wafer (hereinafter, simply referred to as “wafer”) W, which is an example of a circular substrate. This is a device for performing a so-called bevel etching process or a bevel cleaning process for removal.
[0028]
The substrate processing apparatus includes a spin chuck 1 as a substrate holding mechanism, and a process of supplying a processing liquid (chemical solution or pure water) such as an etching liquid or pure water (rinse liquid) to a wafer W held by the spin chuck 1. And a liquid supply nozzle 2.
The spin chuck 1 holds the wafer W substantially horizontally and rotates around a vertical rotation axis passing through the center thereof. The spin chuck 11 has a substrate holding surface 11 a on the upper surface, and a lower surface of the spin base 11. A hollow rotary shaft 12 is provided along the vertical direction, and a rotary drive mechanism 13 for driving the rotary shaft 12 to rotate about a vertical rotary axis.
[0029]
The spin base 11 is formed in a disk shape, and the substrate holding surface 11 a forms a top surface of a flat cylindrical protruding portion in a central region of the upper surface of the spin base 11. In this embodiment, the substrate holding surface 11a is substantially horizontal, and is formed in a circular shape having a smaller radius than the wafer W. The wafer W is held on the substrate holding surface 11a with a water film 5 formed of pure water in a stationary state interposed therebetween. The water surface of the water film 5 is a circle having a smaller radius than that of the wafer W. Therefore, the peripheral edge of the lower surface of the wafer W is exposed without being covered with the water film 5. The wafer W has its device formation surface (active surface) opposed to the substrate holding surface 11a, and the non-active surface opposite to the device formation surface faces upward. Accordingly, the active surface of the wafer W is such that the central device forming region on the device forming surface side is covered with the water film 5 and the outer peripheral portion of the device forming region is exposed.
[0030]
The wafer W placed on the substrate holding surface 11a with the water film 5 interposed therebetween does not receive the atmospheric pressure in the central region of the active surface (lower surface), whereas the wafer W placed on the non-active surface (upper surface) Receive atmospheric pressure. Thus, the wafer W is firmly held on the substrate holding surface 11a via the water film 5.
On the other hand, at the periphery of the water film 5, a surface tension acts on the water surface between the wafer W and the substrate holding surface 11a, and the water film 5 moves between the wafer W and the substrate holding surface 11a by the action of the surface tension. Held in between. As a result, the wafer W is stably held on the substrate holding surface 11a with the water film 5 interposed therebetween.
[0031]
A liquid / gas inlet 15 is formed at the center of the substrate holding surface 11a. A liquid / gas supply pipe 16 inserted through the rotary shaft 12 and a liquid / gas supply passage 17 formed through the spin base 11 and communicating with the liquid / gas introduction port 15 are formed in the liquid / gas introduction port 15. And an inert gas such as pure water or nitrogen gas or air, which is an example of a liquid. Pure water is supplied to the liquid / gas supply pipe 16 from a pure water supply source via a pure water supply valve 18, and inert gas is supplied from an inert gas supply source via a inert gas supply valve 19 to the liquid / gas supply pipe 16. The gas is supplied to the gas supply pipe 16.
[0032]
In the spin base 11, a donut-shaped region around the substrate holding surface 11a forms a counterbore 11b slightly lower than the substrate holding surface 11a, and the counterbore 11b is spaced apart in the circumferential direction. A plurality of (for example, three at equal angular intervals) regulating pins 25 are erected vertically upward (in a direction perpendicular to the spin base 11). The restriction pin 25 is a restriction member for restricting horizontal movement of the wafer W (movement in a direction parallel to the substrate holding surface 11a), has a substantially cylindrical shape, and is vertically eccentric with respect to its axis. It is provided rotatably around a rotation axis 25a along the direction.
[0033]
A regulation pin drive mechanism 20 is provided to rotate the regulation pin 25 around the rotation axis 25a. The regulation pin drive mechanism 20 includes, for example, a link mechanism 21 housed in the internal space of the spin base 11, and a drive mechanism 22 that drives the link mechanism 21. The driving mechanism 22 includes a rotating side driving force transmitting member 23 that rotates together with the rotating shaft 12, a fixed side driving force transmitting member 26 coupled to an outer peripheral side of the rotating side driving force transmitting member 23 via a bearing 24, An elevating drive mechanism 27 for driving the regulating pin for raising and lowering the fixed-side driving force transmitting member 26 is provided.
[0034]
When the fixed driving force transmitting member 26 is moved up and down by the regulating pin driving elevating driving mechanism 27, the rotating driving force transmitting member 23 is moved up and down together with this, and this elevating movement is transmitted to the link mechanism 21 and the regulating pin 25 It is converted into a rotation operation around the rotation axis 25a (rotation within a certain angle range).
Since the rotation axis 25a is eccentric from the center axis of the regulation pin 25, the surface of the regulation pin 25 is brought into contact with the peripheral end surface of the wafer W by operating the regulation pin driving up / down drive mechanism 27 to move the wafer W. The wafer W can be sandwiched, or the surface of the regulating pin 25 can be retracted by a small distance from the peripheral end surface of the wafer W, so that the wafer W can be prevented from jumping out in the horizontal direction. Since the fixed-side driving force transmitting member 26 and the rotating-side driving force transmitting member 23 are coupled via the bearing 24, even when the spin chuck 1 is rotating, the holding / release of the wafer W by the regulating pin 25 is prevented. Can be switched.
[0035]
The processing liquid supply nozzle 2 is provided so as to be able to supply the processing liquid substantially to the center of the upper surface (inactive surface) of the wafer W held by the spin chuck 1. The processing liquid supply nozzle 2 can be supplied with an etching liquid from an etching liquid supply source via an etching liquid supply valve 31 and supply pure water from a pure water supply source via a pure water supply valve 32. Can be.
The opening and closing of the valves 31, 32, 18, and 19 and the operations of the rotation drive mechanism 13 and the control pin drive elevating drive mechanism 27 are controlled by the control unit 30.
[0036]
The unprocessed wafer W is transferred by a transfer robot (not shown), and is transferred onto the substrate holding surface 11a of the spin chuck 1. Prior to the loading of the wafer W, pure water is supplied to the entire surface of the substrate holding surface 11a. The pure water may be supplied from the liquid / gas inlet 15 by opening the pure water supply valve 18 or the pure water supply valve 32 under the control of the control unit 30. You may go from. At this time, the valves 19 and 31 are in a closed state.
[0037]
Pure water for forming the water film 5 on the substrate holding surface 11a may be supplied from a nozzle other than the liquid / gas inlet 15 and the processing liquid supply nozzle 2.
After the pure water is supplied so as to reach the entire surface of the substrate holding surface 11a, the valves 18 and 32 are closed and the supply of the pure water is stopped under the control of the control unit 30. In this state, the transfer robot places the wafer W on the substrate holding surface 11a. Thus, the wafer W is held on the substrate holding surface 11a with the water film 5 interposed therebetween. The active surface of the wafer W faces downward so as to face the substrate holding surface 11a.
[0038]
Next, under the control of the control unit 30, the lifting / lowering drive mechanism 27 for driving the restriction pin is operated, and the wafer W is held by the restriction pin 25. In this state, the rotation drive mechanism 13 starts the rotation of the spin chuck 1 under the control of the control unit 30.
When the rotation of the spin chuck 1 is accelerated to reach a predetermined constant-speed rotation state, the control unit 30 controls the lifting / lowering drive mechanism 27 for driving the regulation pin, thereby releasing the holding of the wafer W by the regulation pin 25. You. As a result, the peripheral end surface of the wafer W is exposed over the entire circumference, and no part is shaded by any member. Moreover, the wafer W is firmly held on the substrate holding surface 11a, and the movement in the horizontal direction is regulated by the regulation pins 25 retracted a small distance from the peripheral end surface of the wafer W. I do not even do.
[0039]
In this state, under the control of the control unit 30, the etching liquid supply valve 31 is opened, and the etching liquid E is discharged from the processing liquid supply nozzle 2. The etching liquid E supplied to the center of the upper surface of the rotating wafer W receives the centrifugal force and travels along the upper surface of the wafer W to spread outward in the rotation radial direction. After reaching the peripheral end surface of the wafer W, the etchant E further flows around to the lower surface (active surface). In this way, the unnecessary material on the upper surface (non-active surface) and the peripheral end surface of the wafer W can be removed by etching, and the unnecessary material on the peripheral portion of the lower surface (active surface) of the wafer W can be removed by etching.
[0040]
The amount of the etchant E flowing to the lower surface of the wafer W can be controlled by controlling the rotation speed of the wafer W. It is preferable that the amount of the wraparound is controlled, for example, so that the etchant wrapping around the lower surface of the wafer W does not reach the water film 5 between the wafer W and the substrate holding surface 11a. That is, the rotation drive mechanism 13 may be controlled by the control unit 30 so that such a wraparound amount is achieved.
[0041]
After the processing with the etching liquid E is performed on the wafer W, the etching liquid supply valve 31 is closed under the control of the control unit 30, and the pure water supply valve 32 is opened instead. Is That is, pure water is supplied toward the center of the upper surface of the wafer W, and the peripheral portions of the upper surface, the peripheral end surface, and the lower surface of the wafer W are rinsed with the pure water.
After the rinsing step, the rotation of the spin chuck 1 is stopped. Prior to the rotation stop, the control unit 30 operates the lifting / lowering drive mechanism 27 for driving the restriction pin, and brings the restriction pin 25 into a sandwiching state in contact with the peripheral end surface of the wafer W. After setting the regulating pin 25 in the sandwiched state, the control unit 30 controls the rotation driving mechanism 13 to reduce the speed of the spin chuck 1 rotating at a constant speed and to guide the spin chuck 1 to a stopped state. After that, the control unit 30 operates the lifting / lowering drive mechanism 27 for driving the restriction pin to release the restriction pin 25.
[0042]
In this state, the wafer W on the substrate holding surface 11a is unloaded by the transfer robot. Prior to the unloading of the wafer W, the pure water supply valve 18 is opened under the control of the control unit 30 so that the pure water is supplied between the liquid / gas inlet 15 and the lower surface of the wafer W and the substrate holding surface 11a. Is supplied. As a result, the wafer W floats on the substrate holding surface 11a and the holding force is weakened, so that the transfer robot can unload the wafer W on the substrate holding surface 11a.
[0043]
When unloading the wafer W, an inert gas may be supplied instead of supplying pure water from the liquid / gas inlet 15. That is, the inert gas may be supplied between the lower surface of the wafer W and the substrate holding surface 11a by opening the inert gas supply valve 19 instead of the pure water supply valve 18. Thereby, the wafer W is in a state of receiving the atmospheric pressure from both the upper and lower surfaces, so that the holding force is weakened, and the transfer robot can carry out the wafer W. For the purpose of releasing the holding of the wafer W on the substrate holding surface 11a, either pure water or an inert gas is introduced between the wafer W and the substrate holding surface 11a from the liquid / gas inlet 15. Therefore, it is sufficient that either the pure water or the inert gas can be supplied to the liquid / gas inlet 15.
[0044]
As described above, according to the configuration of this embodiment, the wafer W is rotated while being held on the substrate holding surface 11a via the water film 5, and in this state, the wafer W is placed on the periphery of the active surface of the wafer W. An etching process or a cleaning process (bevel etching process or bevel cleaning process) can be performed on the substrate.
Since the device formation region on the active surface of the wafer W is protected by the thin water film 5, the splash or mist of the etching solution does not reach this region. In addition, during the process in which the wafer W is rotated at a constant speed, the peripheral end surface of the wafer W is exposed over the entire circumference, so that it is possible to perform a good process over the entire circumference of the wafer W. It is not necessary to change the holding position of the wafer W during the etching process. Therefore, the wear of the parts can be reduced as compared with the above-described prior art in which it is necessary to change the holding position of the wafer by rotating the wafer relative to the spin base.
[0045]
When the rotation of the spin chuck 1 is accelerated or decelerated, the wafer W is clamped by the regulating pin 25. The regulating pin 25 is switched between the clamping state and the released state when the spin chuck 1 is rotating at a constant speed. . Therefore, there is almost no rubbing between the regulating pins 25 and the peripheral end surface of the wafer W, so that the resulting wear is small.
Further, the processing width of the peripheral portion of the wafer W (the amount of the wraparound of the etching solution) can be controlled by controlling the rotation speed of the spin chuck 1, and therefore, in addition to the rotation speed of the spin chuck, the distance between the blocking plate and the wafer. As compared with the above-described prior art in which the flow rate of the inert gas is required to be controlled, the processing width can be accurately controlled.
[0046]
In addition, in the above-described prior art, the distance between the blocking plate and the wafer fluctuates when the wafer holding position is changed, and the processing width of the peripheral portion of the wafer becomes unstable with this. In the configuration of the embodiment, there is no such a problem, and the processing width of the peripheral portion of the wafer W can be accurately controlled throughout the processing period.
Further, it is necessary to prevent the etching liquid from splashing back to the device formation region of the wafer or to continuously supply an inert gas to the active surface of the wafer to control the amount of the etching liquid flowing around the wafer. Since the consumption of the inert gas can be significantly reduced as compared with the above, the running cost of the substrate processing apparatus can be reduced.
[0047]
FIG. 2 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus according to a second embodiment of the present invention. 2, parts corresponding to the respective parts shown in FIG. 1 are denoted by the same reference numerals as those in FIG.
In this embodiment, in the spin base 11, a through-hole 34 is formed in the donut-shaped counterbore 11b in a vertical direction (a direction substantially perpendicular to the substrate holding surface 11a). A rod-shaped elevating pin 35 which is inserted and is capable of moving back and forth in the axial direction is provided. The lift pins 35 are provided in plural (at least three, for example, three at equal angular intervals) at intervals along the circumferential direction of the counterbore 11b. Each lifting pin 35 can be raised and lowered independently of the other lifting pins 35, and a lifting pin driving mechanism 36 is provided for each lifting pin 35, and these are controlled by the control unit 30. ing.
[0048]
When the transfer robot transfers the wafer W to the spin chuck 1, the control unit 30 controls the elevating pin driving mechanism 36, so that at least three elevating pins 35 penetrate the spin base 11 and move from the substrate holding surface 11a. Is also controlled to the raised position where the head is located at a higher position. Then, after pure water for forming the water film 5 is formed on the substrate holding surface 11a, the transfer robot places the wafer W substantially horizontally on the elevating pins 35 at the ascending position.
[0049]
Next, the control unit 30 controls the elevating pin driving mechanism 36 so that the plurality of elevating pins 35 supporting the wafer W are simultaneously lowered, and all the elevating pins 35 have their heads of the spin base 11. The spin guide 11 is guided to a retreat position below the lower surface (a position where the spin base 11 does not interfere with rotation). In this process, the wafer W is placed on the substrate holding surface 11a, and is firmly held on the substrate holding surface 11a via the water film 5.
[0050]
After that, the spin base 11 is rotated to perform the bevel etching or bevel cleaning process and the rinsing process, as in the case of the above-described first embodiment.
When the rinsing process is completed, the rotation of the spin chuck 1 is stopped by the control of the rotation drive mechanism 13 by the control unit 30. At this time, the rotation stop position is determined by the penetrating portion 11b formed on the spin base 11 The hole 34 and the elevating pin 35 are controlled so as to overlap in a plan view.
[0051]
In this state, the control unit 30 controls the lifting pin drive mechanism 36 to raise at least three lifting pins 35. At this time, the raising and lowering pins 35 are controlled so that all the raising and lowering pins 35 to be raised are not raised completely in synchronization with each other, but, for example, there is a difference in the time of contact with the peripheral edge of the lower surface of the wafer W. Is done. As a result, the wafer W is partially lifted up from the water film 5 first, and the wafer W is separated from the water film 5 in one direction. Thus, the wafer W can be separated from the water film 5 without applying an excessive force, and the separated wafer W can be guided to a position above the substrate holding surface 11a. Thereafter, the processed wafer W is unloaded by the transfer robot.
[0052]
Thereafter, when processing the next wafer W, after supplying pure water for forming the water film 5 to the substrate holding surface 11a, the transfer robot moves the unprocessed wafer to the lifting pins 35 at the raised position. W will be delivered.
As described above, in this embodiment, since the separation of the wafer W from the substrate holding surface 11a is performed by moving the elevating pins 35 forward and backward, the spin base 11 needs to be provided with the liquid / gas inlet 15. In addition, the configuration of the spin base 11 can be simplified. In this case, pure water may be supplied to the substrate holding surface 11a from the processing liquid supply nozzle 2.
[0053]
Other configurations and operations are the same as those of the above-described first embodiment, including the configuration and operation of the restriction pin driving mechanism 20.
FIG. 3 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus according to a third embodiment of the present invention. This substrate processing apparatus supplies an etchant from the non-active surface side of the wafer W while holding the wafer W on the substrate holding surface via a water film, as in the first and second embodiments described above. Then, bevel etching or bevel cleaning processing for removing unnecessary substances from the peripheral portion of the wafer W by flowing this etching solution from the peripheral end surface of the wafer W to the active surface side is performed. The point of holding it upward is greatly different.
[0054]
More specifically, the substrate processing apparatus includes a spin chuck 50 and a substrate holding plate 40 that can be held by the spin chuck 50. The spin chuck 50 includes a disk-shaped spin base 51 disposed substantially horizontally, a hollow rotation shaft 52 provided to extend vertically downward from the lower surface of the spin base 51, and a rotation shaft 52 formed around the vertical axis. And a rotation driving mechanism 53 for driving the rotation.
[0055]
A plurality of (for example, three at equal angular intervals) chuck pins 55 are provided at the peripheral edge of the spin base 51 at intervals in the circumferential direction so as to extend vertically upward. The chuck pin 55 has a round bar-shaped shaft portion 55A and a holding portion 55B provided at an upper end of the shaft portion 55A. The holding portion 55B holds the substrate holding plate 40.
The chuck pin 55 is rotatable around a rotation axis 55a passing through the center axis of the shaft portion 55A. A chuck pin driving mechanism 60 is provided to rotate the chuck pin 55 around the rotation axis 55a. The configuration of the chuck pin driving mechanism 60 is the same as the configuration of the regulation pin driving mechanism 20 shown in FIG. That is, the chuck pin drive mechanism 60 includes, for example, a link mechanism 61 housed in the internal space of the spin base 51, and a drive mechanism 62 that drives the link mechanism 61. The drive mechanism 62 includes a rotating-side driving force transmitting member 63 that rotates together with the rotating shaft 52, a fixed-side driving force transmitting member 66 that is coupled to the outer peripheral side of the rotating side driving force transmitting member 63 via a bearing 64, A lifting / lowering driving mechanism 67 for driving the chuck pin for raising / lowering the fixed-side driving force transmitting member 66;
[0056]
When the fixed-side driving force transmission member 66 is moved up and down by the chuck pin driving up-and-down driving mechanism 67, the rotation-side driving force transmission member 63 is moved up and down together with this, and this elevating movement is transmitted to the link mechanism 61, and the chuck pin 55 This is converted into a rotation operation around the rotation axis 55a (rotation within a certain angle range). Thus, it is possible to switch between a state in which the holding portion 55B of the head of the chuck pin 55 holds the substrate holding plate 40 and a state in which the holding is released.
[0057]
As shown in FIG. 4, the substrate holding plate 40 is formed in a disk shape, and a top surface of a flat cylindrical protruding portion in a central region of one surface forms a substrate holding surface 40a. The substrate holding surface 40a is formed in a circular shape having a smaller radius than the wafer W. The donut-shaped area around the substrate holding surface 40a is a counterbore 40b that is recessed from the substrate holding surface 40a.
Pure water is supplied to the substrate holding surface 40a before holding the wafer W. In this state, when the wafer W is brought into close contact with the substrate holding surface 40a, the wafer W is held in close contact with the substrate holding surface 40a across a water film 58 (see FIG. 3) formed by pure water in a stationary state. At this time, the active surface of the wafer W is opposed to the substrate holding surface 40a.
[0058]
The active surface of the wafer W that is in close contact with the substrate holding surface 40a with the water film 58 interposed therebetween does not receive the atmospheric pressure, whereas the non-active surface receives the atmospheric pressure. As a result, the wafer W is firmly and tightly held on the substrate holding surface 40a via the water film 58. On the other hand, surface tension acts on the water surface between the wafer W and the substrate holding surface 40a at the peripheral portion of the water film 58, and by the action of the surface tension, the water film 58 is separated from the wafer W and the substrate holding surface 11a. Held between. As a result, the wafer W is stably held on the substrate holding surface 40a with the water film 58 interposed therebetween.
[0059]
Since the substrate holding surface 40a is a circle with a smaller radius than the wafer W, the water surface where the water film 58 is in contact with the wafer W is a circle with a smaller radius than the wafer W, and the periphery of the active surface of the wafer W is It is in an exposed state without being covered with the water film 58.
With the wafer W held on the substrate holding surface 40a in this manner, the substrate holding plate 40 is transferred to the spin chuck 50 by a transfer robot (not shown), and is held substantially horizontally by the chuck pins 55. Will be. This state is shown in FIG.
[0060]
In a state where the substrate holding plate 40 is held by the spin chuck 50, the wafer W is in a substantially horizontal posture, the active surface thereof faces upward, and the inactive surface faces the upper surface of the spin base 51 therebelow. . Further, the peripheral end surface of the wafer W is in a state having a minute gap with the shaft portion 55A of the chuck pin 55. Therefore, when the wafer W relatively moves in the horizontal direction on the substrate holding surface 40a, the shaft portion 55A acts as a regulating member that regulates such horizontal movement.
[0061]
A through hole 56 penetrating vertically is formed on the rotation axis of the spin base 51, and a processing liquid supply pipe 70 is disposed through the through hole 56 and the inside of the rotation shaft 52. The distal end of the processing liquid supply pipe 70 serves as a processing liquid supply nozzle 71 that supplies an etching liquid or pure water toward the center (substantially on the rotation axis) of the lower surface (inactive surface) of the wafer W. I have. Further, the processing liquid supply pipe 70 can be supplied with an etching liquid from an etching liquid supply source through an etching liquid supply valve 72, and can supply pure water from a pure water supply source through a pure water supply valve 73. It can be supplied.
[0062]
With such a configuration, the spin chuck 50 is rotated while the wafer W is held on the spin chuck 50 via the substrate holding plate 40. On the other hand, the etching liquid supply valve 72 is opened, and the etching liquid E is supplied from the processing liquid supply nozzle 71 to the lower surface of the wafer W. The etchant E receives the centrifugal force and moves radially outward along the lower surface of the wafer W, goes around the peripheral end surface, and reaches the peripheral portion of the upper surface (active surface) of the wafer W. In this manner, the bevel etching process or the bevel cleaning process for removing unnecessary substances on the peripheral end surface and the peripheral portion of the wafer W is performed.
[0063]
The wraparound amount of the etchant E can be optimally controlled by controlling the rotation speed of the spin chuck 50. For example, it is preferable that the amount of the etchant E wrapped around is controlled such that the etchant E wrapped around the upper surface of the wafer W does not reach the water film 58.
After the bevel etching process or the bevel cleaning process is completed, the etchant supply valve 72 is closed, and the pure water supply valve 73 is opened instead. As a result, pure water is supplied to the lower surface, the peripheral end surface, and the peripheral portion of the upper surface of the wafer W, and a rinsing process for washing away the etchant on those surfaces is performed.
[0064]
When the processing on the wafer W is completed in this way, the substrate holding plate 40 holding the wafer W in close contact with the wafer W via the water film 58 is carried out by the transfer robot.
As described above, also in this embodiment, the bevel etching process or the bevel cleaning process can be performed on the wafer W in a state where the wafer W is held on the substrate holding surface 40a via the water film 58. The same effect as in the second embodiment can be obtained.
[0065]
FIG. 5 is a view for explaining a configuration of a substrate transfer hand according to the fourth embodiment of the present invention. The substrate transfer hand 80 is for holding and transferring the wafer W, and has a substrate holding surface 80a for holding the wafer W via a water film. The wafer W may be held with its active surface facing the substrate holding surface 80a, or may be held with its inactive surface facing the substrate holding surface 80a, as necessary.
In this embodiment, the substrate holding surface 80a is a flat surface, is formed in a circle having a radius smaller than the radius of the wafer W, and has a columnar protrusion 82 slightly protruding on one surface of the hand body 81. Of the top.
[0066]
Around the substrate holding surface 80a, regulating members 83 for regulating the movement of the wafer W along the substrate holding surface 80a are provided at a plurality of positions (for example, three places at equal angular intervals) facing the peripheral end surface of the wafer W. Is provided. The regulating member 83 may be, for example, a member in which a round bar-shaped pin is provided upright on the surface of the hand main body 81 on the substrate holding surface 80a side.
The supply of pure water for forming a stationary pure water film between the wafer W and the substrate holding surface 80a may be performed through a liquid / gas inlet 85 opened in the substrate holding surface 80a. Then, the pure water may be supplied to the substrate holding surface 80a from a pure water supply nozzle provided separately from the substrate transfer hand 80.
[0067]
The liquid / gas introduction port 85 communicates with a liquid / gas introduction passage 86 formed inside the hand main body 81. Pure water from a pure water supply source can be supplied to the liquid / gas introduction path 86 via a pure water supply valve 87, and an inert gas (for example, nitrogen gas or air) from an inert gas supply source can be supplied. Can be supplied via an inert gas supply valve 88.
When the wafer W held through the stationary water film is separated from the substrate holding surface 80a, pure water or an inert gas is supplied between the wafer W and the substrate holding surface 80a from the liquid / gas inlet 85. Good. If the holding of the wafer W is released by the supply of the pure water, the configuration for supplying the inert gas is unnecessary.
[0068]
According to this embodiment, since the holding of the wafer W using the stationary water film is stable, the transfer of the wafer W can be reliably performed.
The four embodiments of the present invention have been described above, but the present invention can be embodied in other forms. For example, in the above embodiment, a film of stationary pure water is formed between the wafer W and the substrate holding surfaces 11a, 40a, 80a, but instead of pure water, an alcohol-based solvent (for example, A liquid film of another type of liquid having little influence on the wafer W, such as a liquid film of an organic solvent such as isopropyl alcohol) or a liquid film of ammonia water, may be used. Further, the liquid in close contact with the wafer W does not necessarily have to be in a liquid film state, but may be a relatively large amount of liquid stored in a predetermined concave portion or tank. In this case, the wafer W can be closely held on the liquid surface (upper surface) of the stored liquid.
[0069]
Further, in the above first to third embodiments, an example of the substrate processing apparatus in which the bevel etching process or the bevel cleaning process is performed has been described. However, in the present invention, the etching process or the cleaning process is performed on the entire surface of the substrate. Etching processing equipment and cleaning processing equipment, coater processing equipment for forming a coating film such as a resist on a substrate, development processing equipment for developing a photosensitive film (resist film, etc.) on a substrate after exposure, dry etching The present invention can also be applied to a polymer removing device that removes a residue (polymer) remaining on a substrate such as after. When the present invention is applied to these apparatuses, the substrate to be processed is held with the surface opposite to the surface to be processed (mainly the active surface on which devices and the like are formed) facing the substrate holding surface. Preferably.
[0070]
Further, in the first and second embodiments, the driving mechanism for switching the regulating pin 25 between the sandwiched state and the released state includes an air cylinder and a driving force from the air cylinder in the spin base 11. It can also be realized by a configuration including a link mechanism that operates and rotates the regulating pin 25 around the rotation axis 25a (for example, see Patent Document 1).
In the fourth embodiment, pure water or an inert gas is supplied to the substrate holding surface 80a in order to separate the wafer W from the substrate holding surface 80a. A configuration in which the holding of the wafer W by the substrate holding surface 80a is released by the advancing and retreating pins as described in the second embodiment may be adopted.
[0071]
Further, in the above-described embodiment, the configuration for performing the processing on the wafer has been described. However, the substrate to be processed or transferred may be a circular substrate other than the wafer, or a square substrate such as a glass substrate for a liquid crystal display device. It may be.
In addition, various design changes can be made within the scope of the matters described in the claims.
[Brief description of the drawings]
FIG. 1 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus to which a substrate holding mechanism according to an embodiment of the present invention is applied.
FIG. 2 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus according to a second embodiment of the present invention.
FIG. 3 is an illustrative sectional view for explaining a configuration of a substrate processing apparatus according to a third embodiment of the present invention.
FIG. 4 is a perspective view illustrating a configuration of a substrate holding plate.
FIG. 5 is a diagram illustrating a configuration of a substrate transfer hand according to a fourth embodiment of the present invention.
[Explanation of symbols]
1 Spin chuck
2 Processing liquid supply nozzle
5 Water film
11 Spin Base
11a Substrate holding surface
11b Counterbore
12 Rotary axis
13 Rotation drive mechanism
15 Liquid / gas inlet
16 Liquid / gas supply pipe
17 Liquid / gas supply path
18 Pure water supply valve
19 Inert gas supply valve
20 Regulation pin drive mechanism
21 Link mechanism
22 Drive mechanism
23 Rotation side driving force transmission member
24 bearing
25 Regulatory pin
25a Rotation axis
26 Fixed side driving force transmission member
27 Elevating drive mechanism for regulating pin drive
30 control unit
31 Etching liquid supply valve
32 Pure water supply valve
34 Through hole
35 lifting pins
36 Lifting pin drive mechanism
40 board holding plate
40a substrate holding surface
40b Counterbore
50 Spin chuck
51 Spin Base
52 Rotation axis
53 Rotation drive mechanism
55 chuck pin
55a Rotation axis
55A Shaft
55B clamping part
56 Through hole
58 Water film
60 Chuck pin drive mechanism
61 Link mechanism
62 drive mechanism
63 Rotation side driving force transmission member
64 bearing
66 Fixed side driving force transmission member
67 Elevating drive mechanism for driving chuck pin
70 Treatment liquid supply pipe
71 Processing liquid supply nozzle
72 Etching liquid supply valve
73 Pure water supply valve
80 Substrate transfer hand
80a Board holding surface
81 Hand body
82 Projection
83 Regulator
85 Liquid / gas inlet
86 Liquid / gas introduction path
87 Pure water supply valve
88 Inert gas supply valve
E Etching liquid
W wafer

Claims (11)

While holding the liquid in a stationary state, a substrate holding member that holds the substrate in a state where the liquid and one main surface of the substrate are in close contact with each other,
A regulating member for regulating movement of the substrate held by the substrate holding member. 2. The substrate holding mechanism according to claim 1, further comprising a liquid introducing means for introducing a liquid between the substrate holding member and the substrate. 3. The substrate holding mechanism according to claim 1, further comprising gas introducing means for introducing gas between the substrate holding member and the substrate. Substrate holding that is provided so as to be able to advance and retreat with respect to the one main surface of the substrate held by the substrate holding member, and advances toward one main surface of the substrate, thereby separating the substrate from the substrate holding member. 4. The substrate holding mechanism according to claim 1, further comprising a release member. 5. The substrate processing apparatus according to claim 1, wherein a size of a liquid surface of the liquid between the substrate holding member and the substrate is smaller than a size of the substrate. The substrate holding mechanism according to any one of claims 1 to 5, wherein the substrate holding mechanism is a substrate transfer hand that holds and transfers a substrate. The substrate holding mechanism according to any one of claims 1 to 5, wherein the substrate holding mechanism is a processing chuck that holds the substrate during processing of the substrate. The substrate holding mechanism according to claim 7, wherein the substrate holding mechanism includes a substrate rotating mechanism for rotating the substrate. 9. The substrate holding mechanism according to claim 7, wherein the regulating member is switchable between a clamping state in which the substrate is clamped and a release state in which the clamping of the substrate is released. The substrate holding mechanism according to any one of claims 7 to 9, wherein the substrate holding mechanism is used in a substrate processing apparatus that processes a peripheral portion of a substrate. A substrate holding step of holding the substrate in a state in which the liquid and the one main surface of the substrate are in close contact with each other while holding the liquid stationary by the substrate holding member;
A movement regulating step of regulating movement of the substrate held by the substrate holding member.

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