JP2005252176A - Substrate processor and substrate processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processor where the surface of a substrate can be etched while the surface of the substrate is kept clean. <P>SOLUTION: The substrate processor 1 is provided with a stage 2 for almost horizontally holding a wafer W, a laser beam irradiation device 3 generating a laser beam L and irradiating it, and a plate-like transmission member 4 which is formed of quartz and through which the laser beam L can transmit. The transmission member 4 can be arranged in parallel to the wafer W held by the stage 2 in such a way that the laser beam L from the laser beam irradiation device 3 can transmit it. A substrate facing face 4a being one surface of the transmission member 4 is closely confronted with the wafer W. A resist film R is formed on one surface of the wafer W as the object of a processing. The substrate facing face 4a forms an acquisition face to which particles P generated by irradiation of the laser beam L on the resist film R as an object of removal are stuck and caught. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for removing foreign substances adhering to the surface of various substrates, etching a resist film formed on the surface of a semiconductor substrate, and the like.

  In the manufacturing process of a semiconductor device, foreign matter adheres to the surface of a semiconductor wafer (hereinafter simply referred to as “wafer”). For this reason, it is necessary to clean the surface of the wafer at an appropriate stage. As a wafer cleaning method, wet cleaning using a liquid is the mainstream. Recently, however, dry cleaning has been proposed in which a wafer is irradiated with a laser to remove foreign substances adhering to the wafer surface. This method is suitable for removing minute foreign substances adhering to the wafer.

FIG. 5 is a schematic sectional view showing a structure of a conventional substrate processing apparatus for performing dry cleaning.
The substrate processing apparatus 60 includes a stage 61 for holding the wafer W in a substantially horizontal posture, and a laser beam for generating a laser beam L and irradiating the upper surface of the wafer W held on the stage 61 substantially perpendicularly. An irradiation device 62, a gas injection nozzle 63 that injects an inert gas toward the wafer W held on the stage 61, and a suction nozzle 64 that sucks the gas are provided.

  A moving mechanism 65 is coupled to the stage 61 so that the stage 61 can be moved in a horizontal in-plane direction. Accordingly, the wafer W held on the stage 61 is moved in a horizontal plane with respect to the optical path of the laser beam L irradiated by the laser beam irradiation device 62, and the laser beam L is irradiated on the wafer W. The irradiation target area A, which is the power area, can be moved.

When cleaning the surface of the wafer W, first, the wafer W with the foreign matter B attached to the surface is held on the stage 61 with the surface on the side where the foreign matter B to be removed is directed upward. The irradiation target area A has a size that can contain the foreign matter B almost completely.
Subsequently, the gas injection nozzle 63 is disposed toward the irradiation target area A at a position shifted from above the irradiation target area A above the wafer W held on the stage 61. The suction nozzle 64 is arranged at a symmetrical position where the inert gas injected from the gas injection nozzle 63 toward the irradiation target area A and bounced off by the wafer W can be sucked.

  Next, in a state where the laser beam L is not emitted from the laser beam irradiation device 62, the stage 61 is moved by the moving mechanism 65, and the irradiation target region A is moved so that the foreign matter B can be irradiated with the laser beam. Subsequently, an inert gas is injected from the gas injection nozzle 63, suction is performed by the suction nozzle 64, and a laser beam L is emitted from the laser beam irradiation device 62.

The laser beam L hits the foreign matter B, and the foreign matter B is separated from the surface of the wafer W due to the action of the laser beam L (laser ablation phenomenon), and is blown to the side by the inert gas jetted from the gas jet nozzle 63. It is supposed to be sucked into.
Thereafter, the irradiation target area A is moved by the moving mechanism 65, and the foreign matter B adhering to the other part of the surface of the wafer W is removed by the same procedure.

  The above is a case where the surface of the wafer W is cleaned, but a similar apparatus removes (etches) a predetermined portion of the resist film formed on the entire surface of the wafer W to form an opening pattern in the resist film. Can also be applied. That is, when the resist film is irradiated with the laser beam L, the intermolecular bond is cut off and the substance constituting the resist film is blown off. Thereby, a predetermined portion of the resist film is removed (etched). At this time, solid particles (originating from the resist film) of the resist film are generated. The particles are blown sideways by the inert gas jetted from the gas jet nozzle 63 and sucked by the suction nozzle 64.

Patent Document 1 below discloses an apparatus for removing a photoresist formed on a wafer surface along a predetermined pattern by laser beam irradiation. In this apparatus, the vicinity of the photoresist is in an oxidizing environment, and in this state, the region to be removed of the photoresist is irradiated with a laser beam to burn the photoresist in this region, and the burned removal product can be sucked. Thereby, the surface of the wafer can be kept clean.
Special table 2000-500285 gazette

  However, when the substrate processing apparatus 60 shown in FIG. 5 is used, when the foreign matter B is irradiated with the laser beam L, a laser ablation phenomenon occurs, and the foreign matter B rapidly expands and bumps. Jump out at a very high speed in the direction. For this reason, even if gas is applied to the foreign matter B from the side, it is not actually easy to change the traveling direction of the foreign matter to the direction in which the suction nozzle 64 is disposed. Reattached to the surface of the wafer W without being attracted to the surface. For this reason, the substrate processing apparatus 60 could not clean the wafer W well.

Similarly, when the resist film formed on the surface of the wafer W is etched, the particles of the resist film jump out vigorously in the normal direction of the wafer W. For this reason, some of these particles are not attracted by the suction nozzle 64 and reattach to the surface of the wafer W or the resist film. Therefore, etching cannot be performed while keeping the surface of the wafer W clean.
Further, in the apparatus disclosed in Patent Document 1, it is necessary to perform processing by placing a wafer in an airtight space in order to make the vicinity of the object to be removed an oxidizing environment as described above. For this reason, the structure of the apparatus is complicated, and the apparatus is expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate processing apparatus that can satisfactorily clean the substrate surface.
Another object of the present invention is to provide a substrate processing apparatus capable of etching a substrate surface while keeping the substrate surface clean.
Still another object of the present invention is to provide a simple and inexpensive substrate processing apparatus.

Still another object of the present invention is to provide a substrate processing method capable of satisfactorily cleaning the surface of a substrate.
Still another object of the present invention is to provide a substrate processing method capable of etching a substrate surface while keeping the substrate surface clean.

  The invention according to claim 1 for solving the above-described problem is that a removal object (R) on a substrate (W) is irradiated with a laser beam (L), and the removal object is applied using a laser ablation phenomenon. A substrate processing apparatus (1, 11) for removing, a substrate holding mechanism (2) for holding a substrate, and a laser for generating a laser beam and irradiating the substrate held by the substrate holding mechanism The laser beam is irradiated on the substrate by relatively moving the beam irradiation means (3), the substrate held by the substrate holding mechanism, and the optical path of the laser beam emitted from the laser beam irradiation means. An irradiation target area moving mechanism (5) for moving the irradiation target area (A), which is an area to be formed, and a capture position close to the irradiation target area on the substrate held by the substrate holding mechanism; A particle capturing member (4, 14) having a capturing surface for attaching and capturing particles (P) of the removal target generated by irradiating the removal target in the irradiation target region with a laser beam; A substrate processing apparatus is characterized.

In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.
According to the present invention, the irradiation target region on the substrate can be moved by the irradiation target region moving mechanism so that the irradiation target region and the removal target overlap each other. Further, the particle capturing member can be arranged so that the capturing surface is located at the capturing position. In this state, when the laser beam is irradiated onto the substrate from the laser beam irradiation means, the particles to be removed (particles originating from the removal object) jump out of the substrate by the action of the laser beam (laser ablation phenomenon), It is captured by the particle capturing member.

For this reason, particles to be removed do not re-adhere on the substrate, so the substrate surface (for example, a film formed on the substrate surface) is etched while the substrate is cleaned well or the substrate is kept clean. it can.
Here, the “removal object” refers to removing a predetermined portion of an integrally formed object (for example, a resist film formed on the surface of the wafer) in addition to the minute foreign matter adhering to the substrate. In that case, the predetermined part is included. same as below. When the object to be removed is a predetermined portion of the resist film, the predetermined portion can be etched to form a predetermined opening pattern in the resist film.

Examples of substrates to be processed include various substrates such as semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma displays, photomask substrates, optical disk substrates, magnetic disk substrates, and magneto-optical disk substrates. .
When a plurality of objects to be removed are present on the substrate, for example, when removing a plurality of foreign matters adhering to the substrate, or a plurality of resist films formed on the entire surface of a semiconductor wafer as an example of the substrate When removing a portion, the irradiation target region moving mechanism sequentially moves the irradiation target region so that the irradiation target region and the removal target overlap, and laser irradiation is performed to remove the plurality of removal target objects. Can be removed.

The above operation can be performed in the atmosphere. That is, even if the periphery of the removal target is not adjusted to a special atmosphere, it is possible to remove the removal target and capture the particles generated therewith. For this reason, an apparatus can be comprised simply and cheaply.
The laser beam irradiation unit may irradiate a laser beam in an infrared wavelength region or a visible wavelength region. For example, when the laser beam is in the infrared wavelength region, the removal target can be removed by applying a thermal action. Further, when the foreign matter or the resist film to be removed is an organic substance, the laser beam irradiation means can irradiate a laser beam in the ultraviolet wavelength region. By irradiating the removal object with a laser beam in the ultraviolet wavelength region, the intermolecular bond of these removal objects can be broken and sublimated.

The laser beam emitted from the laser beam irradiation means may be configured to be directly irradiated onto the substrate held by the substrate holding mechanism, and the optical path changing means for changing the optical path of the laser beam such as a mirror or a half mirror. It may be configured to irradiate the substrate via.
The irradiation target area moving mechanism may move the substrate held by the substrate holding mechanism by moving the substrate holding mechanism, or may move the optical path of the laser beam. Both of the optical paths of the beam may be moved. The optical path of the laser beam can be moved by changing the position and orientation of the laser beam irradiation means and the optical path changing means.

  According to a second aspect of the present invention, the particle trapping member faces an area of the substrate surface including the irradiation target area on the optical path of the laser beam from the laser beam irradiation means to the substrate held by the substrate holding mechanism. A translucent member (4) having a substrate facing surface (4a) that includes a translucent member that substantially transmits the laser beam emitted from the laser beam irradiating means; The substrate processing apparatus according to claim 1, further comprising a substrate facing surface.

According to the present invention, the laser beam irradiation means irradiates the removal target on the substrate with the laser beam in a state where the substrate facing surface of the translucent member faces the region of the substrate surface including the irradiation target region. Can do.
In this case, the laser beam can pass through the translucent member and reach the removal target on the substrate surface. When the laser beam hits the object to be removed, the particles of the object to be removed jump out vigorously in a direction away from the substrate (substantially the normal direction of the substrate). Since the translucent member is arranged in this direction, these particles are captured by adhering to the substrate-facing surface of the translucent member. That is, the object to be removed on the substrate is transferred to the substrate facing surface.

The translucent member may be made of quartz. Thereby, a translucent member can be made cheap.
The invention according to claim 3 is the plate-like mask member (14) in which the particle capturing member is formed with an opening (14h) through which the laser beam irradiated from the laser beam irradiation means can pass. A mask member having a substrate facing surface (14a) facing a region of the substrate surface including the irradiation target region and a non-facing surface (14b) which is a surface opposite to the substrate facing surface, The substrate processing apparatus according to claim 1, further comprising the non-facing surface.

According to the present invention, the laser beam is placed in a state where the substrate facing surface faces the region of the substrate surface including the irradiation target region, and the mask member is disposed so that the laser beam from the laser beam irradiation means passes through the opening. It is possible to irradiate the object to be removed on the substrate with a laser beam from the irradiation means.
In this case, the laser beam can pass through the opening of the mask member and reach the removal target on the substrate. When the laser beam hits the removal target, particles of the removal target jump out. Of these particles, the particles that jump out in the direction in which the opening of the mask member exists pass through this opening to the mask member. It reaches the opposite side of the substrate. When the substrate is held in a substantially horizontal posture by the substrate holding mechanism and the mask member is arranged in a substantially horizontal posture above the substrate, such particles accumulate on the non-facing surface of the mask member, Does not reattach to the substrate. Therefore, etching can be performed while the substrate is cleaned well or the substrate surface is kept clean.

The mask member is preferably arranged such that the opening is located in the normal direction of the substrate with respect to the irradiation target region. Since the particles of the removal target almost jump out in the normal direction of the substrate, in this case, most of the particles can pass through the opening and reach the non-opposing surface side of the mask member.
The mask member is preferably made of a material that does not melt even when irradiated with a laser beam (for example, a metal material or a ceramic material having an appropriate melting point). In this case, even if the position of the laser beam is shifted with respect to the opening due to an unexpected situation, the mask member does not melt even if the laser beam hits the mask member.

  If the inner peripheral surface of the opening has a surface along the direction in which the particles of the removal target protrude (direction substantially perpendicular to the mask member), these particles may adhere to such an inner peripheral surface. In this case, the particles may fall away from the inner peripheral surface. In this case, when the substrate is disposed below the mask member, the particles fall on the substrate and reattach. For this reason, in order to prevent particles from adhering to the inner peripheral surface of the opening, the mask member is thinned as a whole, or the cross-sectional shape of the opening is thinned toward the center of the opening. It is preferable to reduce the area of the portion along the direction in which the particles of the removal object jump out. The cross-sectional shape of the opening may be, for example, a funnel shape.

The particle capturing member is preferably provided so as to be removable from the substrate processing apparatus. In this case, the particle trapping member contaminated with the adhered particles can be removed from the substrate processing apparatus and cleaned, or replaced with another clean particle trapping member.
The capturing member may include a plurality of particle capturing units. In this case, the substrate processing apparatus moves an arbitrary particle capturing unit to an irradiation target region by moving the capturing member relative to the substrate holding mechanism. Further, a capturing member moving means that faces the head may be further provided.

  When the capturing surface of the particle capturing member cannot move relative to the irradiation target region, the particles to be removed adhere to substantially the same region of the capturing surface. If a large amount of particles adhere to the same area of the capture surface, the particle capture member will not be able to capture the particles well. In addition, when the particle capturing member includes a translucent member, the translucent member cannot satisfactorily transmit the laser beam due to contamination by particles.

  When the substrate processing apparatus includes a capturing member moving unit and the particle capturing member includes a translucent member, a specific region close to the irradiation target region on the substrate facing surface (capturing surface) of the translucent member is a particle. When it gets dirty, the translucent member can be moved relative to the irradiation target region by the capturing member moving means, and the portion of the substrate facing surface (capturing surface) that is not contaminated with particles can be made to oppose the irradiation target region. Thereby, the translucent member can transmit the laser beam satisfactorily and can adhere the particles to the substrate facing surface (capture surface) satisfactorily.

  Further, when the particle capturing member includes a mask member, the mask member may include a plurality of openings. In this case, if the non-facing surface of the peripheral edge of the specific opening or the inner peripheral surface of the opening is contaminated with particles of the removal target in the mask member, the mask member is moved against the substrate held by the substrate holding mechanism by the capturing member moving means. The position can be moved so that the laser beam passes through another opening (an opening in which the inner peripheral surface and the non-opposing surface of the peripheral edge are not contaminated).

  The particle capturing member is preferably sufficiently large with respect to the irradiation target region, and may be, for example, a flat plate having the same size as the substrate. Moreover, when the particle | grain capture | acquisition member contains a mask member, it is preferable that as many openings as possible are formed at appropriate intervals. In these cases, the substrate can be cleaned or etched for a long time until the entire region of the capturing surface of the particle capturing member is contaminated with particles.

Further, when the translucent member is sufficiently large with respect to the irradiation target region, even if particles of the removal target are ejected in a direction deviated from the normal direction of the substrate, these particles are separated from the substrate facing surface of the translucent member Can be captured.
The invention described in claim 4 is a substrate processing apparatus for irradiating a removal object (R) on a substrate (W) with a laser beam (L) and removing the removal object using a laser ablation phenomenon. 21) a substrate holding mechanism (2) for holding the substrate, a laser beam irradiation means (3) for generating a laser beam and irradiating the substrate held by the substrate holding mechanism, and the substrate A region on which the laser beam from the laser beam irradiation unit is to be irradiated on the substrate by relatively moving the substrate held by the holding mechanism and the optical path of the laser beam irradiated from the laser beam irradiation unit. An irradiation target region moving mechanism (5) for moving the irradiation target region (A), and a laser beam irradiated to the substrate held by the substrate holding mechanism from the laser beam irradiation means. Passes through the inside and has one end disposed close to the irradiation target area, and a suction means (22) for sucking the gas in the vicinity of the irradiation target area through the inside of the tubular member. A substrate processing apparatus comprising:

  According to this invention, the laser beam irradiation means places one end close to the irradiation target region in a state where the irradiation target region and the removal target on the substrate are aligned by the irradiation target region moving mechanism. The object to be removed on the substrate can be irradiated with a laser beam through the inside of the formed tubular member. At this time, if the gas in the vicinity of the irradiation target region is sucked through the inside of the tubular member by the suction device, the particles of the removal target generated by the laser ablation phenomenon are sucked into the suction device through the inside of the tubular member. Is done.

At this time, the tubular member is preferably disposed substantially perpendicular to the substrate held by the substrate holding mechanism. In this case, the tubular member is located in the normal direction of the substrate with respect to the irradiation target region. Most of the particles to be removed jump out in the normal direction of the substrate. Therefore, in this case, the direction in which the particles of the removal object jump out and the direction in which the particles are sucked substantially coincide.
For this reason, since the particles can be sucked with almost no change in the direction of the particles to be removed, most of the particles are sucked into the suction device so as not to reattach to the substrate held by the substrate holding mechanism. be able to. Therefore, the substrate surface (for example, a film formed on the substrate surface) can be etched while the substrate surface is well cleaned or the substrate surface is kept clean.

  The invention described in claim 5 is a substrate processing method for irradiating a removal target (R) on a substrate (W) with a laser beam (L) and removing the removal target using a laser ablation phenomenon. The substrate and the substrate to be removed so that the irradiation target region (A), which is a region to be irradiated with the laser beam emitted from the laser beam irradiation means (3), overlaps the removal target on the substrate. A positioning step for relatively moving the optical path of the laser beam, and a capture surface for adhering and capturing particles (P) of the removal target generated by irradiating the removal target on the substrate with the laser beam A particle capturing member disposing step of disposing the capturing surface of the particle capturing member (4, 14) having a proximity to the irradiation target region at a capturing position where the particles to be removed can be captured, the positioning step, and After the particle capturing member arranging step, the laser beam irradiating step of irradiating the substrate with the laser beam from the laser beam irradiating means, and the particles to be removed generated by the laser ablation phenomenon accompanying the laser beam irradiating step, And a particle capturing step of capturing the particles by adhering to the capturing surface of the particle capturing member disposed at the capturing position.

This substrate processing method can be carried out by the substrate processing apparatus according to the first aspect, and can provide the same effects as the substrate processing apparatus according to the first aspect.
In the particle capturing member arranging step, the particle capturing member is preferably arranged so that the distance from the substrate is 1 μm to 1 mm, and more preferably 1 μm to 0.1 mm. .

  According to a sixth aspect of the present invention, the particle capturing member is a translucent member (4) having a substrate facing surface (4a) capable of facing the substrate, and the laser beam irradiated in the laser beam irradiation step is used. A substrate surface including a translucent member that is substantially transmissive, wherein the particle capturing member disposing step is on the optical path of the laser beam to be irradiated in the laser beam irradiation step, and the substrate facing surface includes the irradiation target region; Including the step of disposing the translucent member so as to face the region, and the particle capturing step includes a step of attaching the particles to be removed to the substrate facing surface forming the capturing surface. The substrate processing method according to claim 5.

This substrate processing method can be carried out by the substrate processing apparatus according to the second aspect, and can provide the same effects as the substrate processing apparatus according to the second aspect.
Invention of Claim 7 includes the plate-shaped mask member (14) in which the said particle | grain capture member was formed with the opening (14h) which can let the laser beam irradiated from the said laser beam irradiation means pass, In the particle capturing member arranging step, a laser to be irradiated in the laser beam irradiation step in which one surface of the mask member forming the substrate facing surface (14a) is opposed to a region of the substrate surface including the irradiation target region. Arranging the mask member so that a beam passes through the opening, and the particle capturing step is performed on a non-facing surface (14b) that forms the capturing surface on a surface opposite to the substrate facing surface; 6. The substrate processing method according to claim 5, further comprising a step of adhering the particles to be removed.

This substrate processing method can be carried out by the substrate processing apparatus according to the third aspect, and can provide the same effects as the substrate processing apparatus according to the third aspect.
The invention described in claim 8 is a substrate processing method for irradiating a removal object (R) on a substrate (W) with a laser beam (L) and removing the removal object using a laser ablation phenomenon. The substrate and the substrate to be removed so that the irradiation target region (A), which is a region to be irradiated with the laser beam emitted from the laser beam irradiation means (3), overlaps the removal target on the substrate. An alignment step of relatively moving the optical path of the laser beam, and a tubular member (24) through which the laser beam can pass through the interior, the laser beam can pass through the interior, and one end of the tubular member (24) A laser beam irradiator that irradiates the substrate with a laser beam from the laser beam irradiation means after the step of disposing the substrate, the step of positioning, and the step of disposing the tubular member. In parallel with the laser beam irradiation step, fine particles to be removed generated by the laser ablation phenomenon accompanying the laser beam irradiation step by sucking the gas in the vicinity of the irradiation target region through the inside of the tubular member And a suction step of removing (P) by suction.

This substrate processing method can be carried out by the substrate processing apparatus according to the fourth aspect, and can provide the same effects as the substrate processing apparatus according to the fourth aspect.
The optical path of the laser beam to be irradiated from the laser beam irradiation means and the tubular member may be fixed so that the laser beam always passes through the inside of the tubular member. In this case, it is not necessary to align the tubular member so that the laser beam to be irradiated from the laser beam irradiation means passes through the inside each time the step of arranging the tubular member is performed.

  The step of arranging the tubular member preferably includes a step of arranging the tubular member substantially perpendicular to the substrate to be processed. In this case, the direction in which the particles of the removal target are ejected (the normal direction of the substrate) and the direction in which the particles are attracted (the direction in which the tubular member is disposed) substantially coincide with each other. These particles can be sucked. Therefore, most particles can be sucked easily.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic sectional view showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention.
The substrate processing apparatus 1 includes a stage 2 for holding a semiconductor wafer (hereinafter simply referred to as “wafer”) W in a substantially horizontal posture, and a laser beam irradiation apparatus 3 for generating and irradiating a laser beam L. I have. The stage 2 can hold the wafer W by vacuum-sucking the lower surface of the wafer W. The laser beam irradiation apparatus 3 includes a KrF laser, and can generate and emit a laser beam L having a wavelength of 248 nm (ultraviolet wavelength region). A cross section perpendicular to the traveling direction of the laser beam L has a substantially circular shape.

  The laser beam L emitted from the laser beam irradiation device 3 is irradiated almost perpendicularly onto the surface of the wafer W attracted and held on the stage 2. In this embodiment, the laser beam L emitted from the laser beam irradiation device 3 is directly irradiated onto the wafer W held on the stage 2, but is reflected by a mirror, a half mirror, etc. The wafer W held by 2 may be irradiated.

In addition, the substrate processing apparatus 1 includes a flat plate-like translucent member 4 made of quartz, and the translucent member 2 faces the upper surface of the wafer W sucked and held on the stage 2 substantially horizontally. It is possible to arrange it. The translucent member 4 is detachable from the substrate processing apparatus 1.
A stage moving mechanism 5 is coupled to the stage 2. The stage moving mechanism 5 can move the stage 2 in an arbitrary direction within a horizontal plane. Further, a translucent member moving mechanism 6 is coupled to the translucent member 4, and the translucent member 4 is placed on an arbitrary surface in a plane parallel to the wafer W with respect to the wafer W held on the stage 2. It can be moved in the direction.

Operations of the laser beam irradiation device 3, the stage moving mechanism 5, and the translucent member moving mechanism 6 are controlled by the control unit 7.
A plurality of rectangular pads 9 made of copper and having a side length of about 100 μm are formed on one surface of the wafer W to be processed. In this embodiment, the size (length of one side) of the pad 9 is larger than the size (diameter) of the cross section perpendicular to the traveling direction of the laser beam L. A resist film R made of an organic material is formed over the entire surface of this one surface (surface on which the pads 9 are formed) of the wafer W, and all the pads 9 are covered with the resist film R. .

A procedure for exposing the pad 9 by removing (etching) a portion of the resist film R existing on the pad 9 using the substrate processing apparatus 1 will be described below. In this case, the removal target is a part of the resist film R.
First, the wafer W is sucked and held on the stage 2 with the surface on which the resist film R is formed facing up. Subsequently, the translucent member 4 is disposed in proximity to the wafer W so as to be substantially parallel to the wafer W. The lower surface of the translucent member 4 forms a substrate facing surface 4 a that faces the wafer W. The distance between the wafer W and the translucent member 4 is 1 μm to 1 mm, preferably 1 μm to 0.1 mm.

Subsequently, in a state where the laser beam L is not emitted from the laser beam irradiation device 3, the stage moving mechanism 5 is controlled by the control unit 7, and the portion to be removed in the resist film R and the laser beam L on the wafer W are emitted. The stage 2 is moved so that an area to be irradiated (hereinafter referred to as “irradiation target area”) A overlaps.
Next, the laser beam L is emitted from the laser beam irradiation device 3 under the control of the control unit 7. The laser beam L passes through the translucent member 4 made of quartz and reaches the surface of the resist film R.

  As a result, the molecules constituting the resist film R in the irradiation target region A are sublimated by breaking the intermolecular bond by the action of the laser beam L (laser ablation phenomenon). Along with this, solid particles P originating from the resist film R are generated. The particles P are captured by jumping upward (in the normal direction of the wafer W) at a high speed and adhering to the vicinity of the facing portion of the irradiation target area A on the substrate facing surface 4a of the translucent member 4. Therefore, the particles P do not reattach to the surface of the wafer W or the resist film R. Thus, in this embodiment, the substrate facing surface 4a forms a capturing surface for capturing the particles P.

  By continuing the irradiation with the laser beam L for an appropriate time, the resist film R in the irradiation target region A is almost completely removed. Since the size of the pad 9 is larger than the size of the cross section perpendicular to the traveling direction of the laser beam L (the size of the irradiation target area A), only a part of one pad 9 is exposed from the resist film R by the above operation. . Therefore, in order to further remove the resist film R on the pad 9, the stage moving mechanism 5 is controlled by the control unit 7 to move the stage 2, and the irradiation target area A exists on the pad 9 in the resist film R. It is moved to the part to be.

  In this state, the irradiation of the laser beam L for an appropriate time is continued, whereby the resist film R in the irradiation target area A is almost completely removed. By repeating the above operation, one pad 9 is completely exposed from the resist film R. While moving the irradiation target area A within the area corresponding to the pad 9, the irradiation with the laser beam L may be continued until the resist film R existing on the pad 9 is completely removed.

The size of the cross section perpendicular to the traveling direction of the laser beam L (the size of the irradiation target area A) may be larger than the size of the pad 9. In this case, one pad 9 can be completely exposed from the resist film R without moving the irradiation target area A.
Next, the emission of the laser beam L from the laser beam irradiation device 3 is stopped under the control of the control unit 7. Then, the stage moving mechanism 6 is controlled by the control unit 7 so that the irradiation target area A is moved onto another pad 9. In the same manner as described above, the resist film R is irradiated with the laser beam L, and the pad 9 is completely removed from the resist film R.

By repeating the above steps, all the pads 9 are exposed from the resist film R. In this way, when the processing of one wafer W is completed, this wafer W is carried out from the stage 2, and the next wafer W is sucked and held on the stage 2, and the same processing is performed.
While such an operation is repeated, the substrate facing surface 4a (lower surface) of the translucent member 4 is contaminated by the particles P. For this reason, the laser beam L cannot pass through the translucent member 4 well, and the resist film R cannot be removed efficiently. Further, since a large amount of particles P adhere to a limited region of the translucent member 4, the translucent member 4 cannot adhere the particles P well, and once adhered to the translucent member 4 (or The hitting particles P may fall and reattach to the surface of the wafer W or the resist film R.

  In order to avoid such a situation, on the substrate facing surface 4 a of the translucent member 4, before the vicinity of the facing portion of the irradiation target area A is contaminated with particles P to a certain level or more, the control portion 7 performs translucency. The member moving mechanism 6 is controlled so that the translucent member 4 is moved by an appropriate distance in a direction in a plane horizontal to the wafer W. As a result, the portion of the translucent member 4 that is not contaminated with the particles P can be transmitted by the laser beam L, and the particles P are favorably adhered to the portion of the substrate facing surface 4a that is not contaminated with the particles P. You can

  When one or more wafers W are processed, the translucent member 4 becomes unusable because most of the substrate facing surface 4a becomes dirty with the particles P. In this case, the translucent member 4 is removed from the substrate processing apparatus 1. Then, after the removed translucent member 4 is cleaned, it is attached to the substrate processing apparatus 1 again, or another clean translucent member 4 is attached to the substrate processing apparatus 1.

By the method as described above, the particles P generated along with the removal of the resist film R can be captured by the translucent member 4 and prevented from reattaching to the surface of the wafer W or the resist film R. That is, the resist film R formed on the surface of the wafer W can be etched while keeping the wafer W (resist film R) clean.
Moreover, the above operation can be performed in air | atmosphere. That is, even if the periphery of the resist film R to be removed is not adjusted to a special atmosphere (for example, an oxidizing atmosphere), a predetermined portion of the resist film R can be removed and the particles P generated thereby can be captured. . For this reason, the substrate processing apparatus 1 can be configured simply and inexpensively.

Regardless of this method, if the particles P are reattached to the wafer W (resist film R) and then the particles P are removed by wet cleaning using water, the resist film R may be altered. In the above method, since the processing is performed without using any cleaning agent such as water, the resist film R is not altered.
FIG. 2 is a schematic cross-sectional view showing the configuration of the substrate processing apparatus according to the second embodiment of the present invention. 2, parts corresponding to those shown in FIG. 1 are denoted by the same reference numerals as those in FIG.

  The substrate processing apparatus 11 includes a flat mask member 14 instead of the translucent member 4 of the substrate processing apparatus 1 of FIG. The mask member 14 is made of a metal material or a ceramic material having a melting point that does not melt even when the laser beam L is irradiated. The mask member 14 can be disposed close to and parallel to the wafer W held by suction on the stage 2 and is detachable from the substrate processing apparatus 11.

  FIG. 3 is a schematic plan view of the mask member 14. 2 and 3, the mask member 14 is formed with a substantially circular opening 14 h having a diameter slightly larger than the beam diameter of the laser beam L. In the vicinity of the opening 14h, the mask member 14 has a cross-sectional shape such that the thickness decreases toward the center of the opening 15h, and the opening 14h has an inner peripheral surface oriented along the direction in which the particles P protrude. Not done.

  In a cross section that includes the opening 14h and is perpendicular to the mask member 14 (see FIG. 2), the mask member 14 has a funnel-like shape that opens to one surface (hereinafter referred to as “non-opposing surface”) 14b at a large angle (obtuse angle). The mask member 14 is thinner toward the center of the opening 15h. That is, the inner diameter of the opening 14 h increases from the other surface (hereinafter referred to as “substrate facing surface”) 14 a side of the mask member 14 toward the non-facing surface 14 b side.

A plurality of openings 14h are formed in the mask member 14, and these openings 14h are arranged in a lattice pattern (see FIG. 3).
Referring to FIG. 2, a mask member moving mechanism 16 is coupled to the mask member 14, and the mask member 14 is placed on an arbitrary surface in a plane parallel to the wafer W with respect to the wafer W held on the stage 2. Can be moved in the direction. Operations of the laser beam irradiation device 3, the stage moving mechanism 5, and the mask member moving mechanism 16 are controlled by the control unit 17.

Hereinafter, with respect to the wafer W on which the pad 9 and the resist film R similar to those described in the description of the first embodiment are formed using the substrate processing apparatus 11, a portion existing on the pad 9 in the resist film R A procedure for removing (etching) the pad 9 to expose the pad 9 will be described.
First, the wafer W is sucked and held on the stage 2 with the surface on which the resist film R is formed facing up. Subsequently, the mask member 14 is disposed in close proximity to the wafer W in parallel. The mask member 14 is oriented so that the substrate facing surface 14a faces the wafer W. At this time, the opening 14h expands upward, and the inner peripheral surface 14s of the opening 14h has a gentle inclination and faces upward. Further, the inner peripheral surface 14 s of the opening 14 h does not have a direction portion along the normal direction of the wafer W.

The distance between the wafer W and the mask member 14 is 1 μm to 1 mm, preferably 1 μm to 0.1 mm.
Next, in a state where the laser beam L is not emitted from the laser beam irradiation device 3, the mask member moving mechanism 16 is controlled by the control unit 17, and the laser beam L from the laser beam irradiation device 3 passes through the opening 14 h of the mask member 14. The mask member 14 is moved so that one can pass. Subsequently, the stage moving mechanism 5 is controlled by the control unit 17, and the stage 2 is moved so that the portion to be removed in the resist film R and the irradiation target area A overlap.

Thereafter, the laser beam L is emitted from the laser beam irradiation device 3 under the control of the control unit 17. The laser beam L passes through the opening 14 h of the mask member 14 and reaches the surface of the resist film R. At this time, even if the laser beam L is applied to the mask member 14 due to an unexpected situation, the mask member 14 does not melt.
Molecules constituting the resist film R in the irradiation target area A are sublimated by the action of the laser beam L, and accordingly, solid particles P originating from the resist film R are generated. The particles P jump out upward (in the normal direction of the wafer W) at a high speed, pass through the opening 14 h of the mask member 14, and reach the opposite side of the wafer W with respect to the mask member 14. These particles P adhere to and are deposited (trapped) on the inner peripheral surface 14s of the opening 14h and the upper surface (non-opposing surface 14b) of the mask member 14. For this reason, the particles P do not reattach to the surface of the wafer W or the resist film R. Thus, in this embodiment, the inner peripheral surface 14s and the non-facing surface 14b form a capturing surface for capturing the particles P.

Thereafter, one pad 9 is exposed from the resist film R by the same procedure as that when the substrate processing apparatus 1 according to the first embodiment is used. Similarly, all other pads 9 are exposed from the resist film R.
During this time, the inner peripheral surface 14s of the opening 14h and the surrounding non-facing surface 14b are contaminated by the particles P. Since these particles P are on the inner peripheral surface 14 s and the mask member 14 facing upward, they are not easily dropped from the mask member 14. However, if a large amount of particles P adhere to a limited area of the capture surface (the inner peripheral surface 14s and the non-opposing surface 14b), the capture surface cannot capture the particles P well. In this case, for example, when vibration is applied to the mask member 14, the particles P once captured on the capturing surface fall through the openings 14 h and reattach to the surfaces of the wafer W and the resist film R.

  In order to avoid such a situation, the mask member moving mechanism 16 is controlled by the control unit 17 before the contamination of the area where the particles P adhere on the trapping surface exceeds a certain level, and the mask member 14 is moved to the wafer W. The laser beam L is allowed to pass through another opening 14h (the inner peripheral surface 14s and the surrounding non-opposing surface 14b are not contaminated). By such an operation, the particles P can be satisfactorily captured on the capturing surface of the mask member 14 until the inner peripheral surface 14s of all the openings 14h and the surrounding non-opposing surface 14b are contaminated with the particles P to a certain level or more.

When the inner peripheral surface 14s of all the openings 14h of the mask member 14 and the surrounding non-opposing surface 14b are contaminated with the particles P, the mask member 14 is removed from the substrate processing apparatus 11. Then, after the removed mask member 14 is cleaned, it is attached to the substrate processing apparatus 11 again, or another clean mask member 14 is attached to the substrate processing apparatus 11.
By the method as described above, the particles P generated along with the removal of the resist film R can be captured by the mask member 14 and prevented from reattaching to the surface of the wafer W or the resist film R. That is, the resist film R formed on the surface of the wafer W can be etched while keeping the wafer W (resist film R) clean.

Since the above operation can also be performed in the atmosphere, the configuration of the substrate processing apparatus 11 can be simplified and the substrate processing apparatus 11 can be made inexpensive.
FIG. 4 is a schematic cross-sectional view showing the configuration of the substrate processing apparatus according to the third embodiment of the present invention. 4, parts corresponding to those shown in FIG. 1 are denoted by the same reference numerals as those in FIG.

The substrate processing apparatus 21 includes a straight tubular cylindrical member 24 instead of the translucent member 4. Further, the substrate processing apparatus 21 includes a suction device 22 that sucks the inside of the cylindrical member 24.
The cylindrical member 24 can be arranged so that the lower end thereof is positioned in the vicinity of the wafer W substantially perpendicular to the wafer W held on the stage 2. In the cylindrical member 24 in this state, the suction device 22 can suck the inside of the cylindrical member 24 through a portion other than the lower end of the cylindrical member 24.

The inner diameter of the cylindrical member 24 is larger than the beam diameter of the laser beam L emitted from the laser beam irradiation device 3. The laser beam L emitted from the laser beam irradiation device 3 passes through the inside of the cylindrical member 24 and is irradiated onto the wafer W held on the stage 2.
The operations of the laser beam irradiation device 3, the stage moving mechanism 5, and the suction device 22 are controlled by the control unit 27.

Hereinafter, with respect to the wafer W on which the pad 9 and the resist film R similar to those described in the description of the first embodiment are formed using the substrate processing apparatus 11, a portion existing on the pad 9 in the resist film R A procedure for removing (etching) the pad 9 to expose the pad 9 will be described.
First, the wafer W is sucked and held on the stage 2 with the surface on which the resist film R is formed facing up. Subsequently, in a state where the laser beam L is not emitted from the laser beam irradiation apparatus 3, the stage moving mechanism 5 is controlled by the control unit 27 so that the portion to be removed from the resist film R and the irradiation target area A overlap. Stage 2 is moved. The cylindrical member 24 is substantially perpendicular to the wafer W so that the laser beam L to be emitted from the laser beam irradiation device 3 can pass through the inside of the cylindrical member 24, and its lower end is close to the wafer W. Are arranged as follows. In this state, the lower end of the cylindrical member 24 is close to the irradiation target area A.

The positional relationship and orientation of the laser beam irradiation device 3 and the cylindrical member 24 may be fixed so that the laser beam L emitted from the laser beam irradiation device 3 always passes through the inside of the cylindrical member 24.
Next, the suction device 22 is operated under the control of the control unit 27. Thereby, the gas in the vicinity of the irradiation target area A is sucked into the suction device 22 through the inside of the cylindrical member 24. Thereafter, the laser beam L is emitted from the laser beam irradiation device 3 under the control of the control unit 27. The laser beam L passes through the inside of the cylindrical member 24 and reaches the surface of the resist film R.

  As a result, the molecules constituting the resist film R in the irradiation target region A are sublimated by breaking the intermolecular bond by the action of the laser beam L (laser ablation phenomenon). Along with this, solid particles P originating from the resist film R are generated. The particles P jump out upward (in the normal direction of the wafer W) at a high speed, and are sucked into the suction device 22 through the inside of the cylindrical member 24. Therefore, the particles P do not reattach to the surface of the wafer W or the resist film R.

  At this time, the direction in which the particles P jump out and the direction in which the cylindrical member 24 is arranged, that is, the direction in which the particles P are sucked substantially coincide. Therefore, unlike the case where the conventional substrate processing apparatus 60 is used (see FIG. 5), the particles P can be sucked in the vicinity of the irradiation target area A with almost no change in the direction in which the particles P jump out. For this reason, since most of the particles P can be sucked, the number of particles P that re-adhere to the surfaces of the wafer W and the resist film R can be remarkably reduced.

Thereafter, one pad 9 is exposed from the resist film R by the same procedure as that when the substrate processing apparatus 1 according to the first embodiment is used. Similarly, all other pads 9 are exposed from the resist film R.
By the above method, the resist film R formed on the surface of the wafer W can be etched while keeping the wafer W (resist film R) clean.

Since the above operation can also be performed in the atmosphere, the configuration of the substrate processing apparatus 21 can be simplified, and the substrate processing apparatus 21 can be made inexpensive.
Although the embodiments of the present invention have been described above, the present invention can be implemented in other forms. For example, in each of the above embodiments, a method for removing a predetermined portion of the resist film R formed on the wafer W has been described. However, the same processing is performed using the same substrate processing apparatus 1, 11, 21. By the same method, foreign matter adhering on the substrate (not limited to the wafer W) can be removed. In this case, instead of moving the stage 2 so that the portion to be removed in the resist film R and the irradiation target area A overlap, the stage 2 is moved so that the foreign matter on the substrate and the irradiation target area A overlap. do it.

  In the above embodiment, the stage moving mechanism 5 for moving the stage 2 is provided to move the irradiation target area A on the wafer W, but the wafer W is irradiated from the laser beam irradiation apparatus 3. Means for moving the optical path of the laser beam L may be provided. For example, a moving mechanism for moving the laser beam irradiation apparatus 3 in the in-plane direction (direction perpendicular to the laser beam L) of the wafer W held on the stage 2 may be provided. Moreover, both such a moving mechanism and the stage moving mechanism 2 may be provided.

  The wavelength of the laser beam L emitted from the laser beam irradiation device 3 can be arbitrarily selected so that the laser ablation phenomenon occurs efficiently when the laser beam L hits the object to be removed. The cross-sectional shape of the laser beam L emitted from the laser beam irradiation device 3 is not limited to a circle, and may be a rectangle, for example. Further, the laser beam L generated by the laser beam irradiation device 3 may emit continuously or may emit pulses.

  In addition, various modifications can be made within the scope of the matters described in the claims.

1 is a schematic sectional view showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention. It is an illustration sectional view showing the composition of the substrate processing device concerning a 2nd embodiment of the present invention. It is an illustration top view of the mask member which looks down at a non-opposing surface. It is an illustration sectional view showing the composition of the substrate processing device concerning a 3rd embodiment of the present invention. It is an illustration sectional view showing the structure of the conventional substrate processing device for carrying out dry cleaning.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,11,21 Substrate processing apparatus 2 Stage 3 Laser beam irradiation apparatus 4 Translucent member 4a, 14a Substrate facing surface 5 Stage moving mechanism 7, 17, 27 Control part 14 Mask member 14b Non-opposing surface 14h Opening 14s Inner peripheral surface 22 Suction Device 24 Cylindrical Member A Irradiation Target Area L Laser Beam P Particle R Resist Film W Wafer

Claims (8)

A substrate processing apparatus for irradiating a removal object on a substrate with a laser beam and removing the removal object using a laser ablation phenomenon,
A substrate holding mechanism for holding the substrate;
A laser beam irradiation means for generating a laser beam and irradiating the substrate held by the substrate holding mechanism;
An irradiation target that is an area to be irradiated with the laser beam on the substrate by relatively moving the substrate held by the substrate holding mechanism and the optical path of the laser beam irradiated from the laser beam irradiation means. An irradiation target area moving mechanism for moving the area;
At the capture position close to the irradiation target region on the substrate held by the substrate holding mechanism, particles of the removal target generated by irradiating the removal target in the irradiation target region with a laser beam are attached. A substrate processing apparatus comprising: a particle capturing member having a capturing surface for capturing. The particle capturing member has a substrate facing surface that faces a region of the substrate surface including the irradiation target region on the optical path of the laser beam from the laser beam irradiation means to the substrate held by the substrate holding mechanism. A translucent member that substantially transmits the laser beam emitted from the laser beam irradiation means,
The substrate processing apparatus according to claim 1, wherein the capturing surface includes the substrate facing surface. The particle capturing member is a plate-like mask member in which an opening through which a laser beam irradiated from the laser beam irradiation unit can pass is formed, and is opposed to a region of the substrate surface including the irradiation target region. A mask member having a substrate facing surface and a non-facing surface which is a surface opposite to the substrate facing surface;
The substrate processing apparatus according to claim 1, wherein the capturing surface includes the non-facing surface. A substrate processing apparatus for irradiating a removal object on a substrate with a laser beam and removing the removal object using a laser ablation phenomenon,
A substrate holding mechanism for holding the substrate;
A laser beam irradiation means for generating a laser beam and irradiating the substrate held by the substrate holding mechanism;
The laser beam from the laser beam irradiation unit on the substrate is irradiated by relatively moving the substrate held by the substrate holding mechanism and the optical path of the laser beam irradiated from the laser beam irradiation unit. An irradiation target area moving mechanism for moving the irradiation target area which is a power area;
A tubular member in which a laser beam applied to the substrate held by the substrate holding mechanism from the laser beam irradiation means passes through the inside, and one end is disposed close to the irradiation target region; and
A substrate processing apparatus comprising: suction means for sucking a gas in the vicinity of the irradiation target region through the inside of the tubular member. A substrate processing method for irradiating a removal object on a substrate with a laser beam and removing the removal object using a laser ablation phenomenon,
The substrate and the optical path of the laser beam are relatively relative to each other so that the irradiation target region, which is the region to be irradiated with the laser beam emitted from the laser beam irradiation unit, overlaps the removal target on the substrate. Moving alignment process;
The capturing surface of the particle capturing member having a capturing surface that attaches and captures particles of the removal target generated by irradiating the removal target on the substrate with the laser beam is close to the irradiation target region, A particle capturing member disposing step for disposing the particles to be removed at a capturing position capable of capturing;
After the alignment step and the particle capturing member arrangement step, a laser beam irradiation step of irradiating the substrate with a laser beam from the laser beam irradiation means;
A particle capturing step of capturing particles by attaching the particles of the removal target generated by the laser ablation phenomenon accompanying the laser beam irradiation step to the capturing surface of the particle capturing member disposed at the capturing position. Substrate processing method. The particle capturing member is a light transmissive member having a substrate facing surface that can face the substrate, and includes a light transmissive member that substantially transmits the laser beam irradiated in the laser beam irradiation step,
In the particle capturing member arranging step, the translucent property is set so that the substrate facing surface faces the region of the substrate surface including the irradiation target region on the optical path of the laser beam to be irradiated in the laser beam irradiation step. Including a step of arranging a member;
The substrate processing method according to claim 5, wherein the particle capturing step includes a step of attaching particles of the removal target to the substrate facing surface forming the capturing surface. The particle capturing member includes a plate-shaped mask member in which an opening through which a laser beam irradiated from the laser beam irradiation unit can pass is formed,
In the particle capturing member arranging step, one surface of the mask member forming the substrate facing surface is opposed to a region of the substrate surface including the irradiation target region, and the laser beam to be irradiated in the laser beam irradiation step is Disposing the mask member so as to pass through the opening,
6. The substrate according to claim 5, wherein the particle capturing step includes a step of adhering particles of the object to be removed to a non-facing surface that forms the capturing surface on a surface opposite to the substrate facing surface. Processing method. A substrate processing method for irradiating a removal object on a substrate with a laser beam and removing the removal object using a laser ablation phenomenon,
The substrate and the optical path of the laser beam are relatively relative to each other so that the irradiation target region, which is the region to be irradiated with the laser beam emitted from the laser beam irradiation unit, overlaps the removal target on the substrate. Moving alignment process;
A step of arranging a tubular member through which the laser beam can pass through, so that the laser beam can pass through the inside, and one end thereof is close to the irradiation target region;
After the positioning step and the step of arranging the tubular member, a laser beam irradiation step of irradiating the substrate with a laser beam from the laser beam irradiation means;
In parallel with the laser beam irradiation step, by sucking a gas in the vicinity of the irradiation target region through the inside of the tubular member, the particles to be removed generated by the laser ablation phenomenon accompanying the laser beam irradiation step are sucked. And a suction process for removing the substrate.

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