JP4594767B2 - Substrate peripheral processing equipment - Google Patents

Description

  The present invention relates to a method and apparatus for processing the outer peripheral portion of a base material such as a semiconductor wafer or a liquid crystal display substrate, and in particular, removes the inorganic film and the organic film on the outer peripheral portion of the base material in which the inorganic film and the organic film are laminated. The present invention relates to a method and apparatus suitable for processing.

  When manufacturing a semiconductor device, a portion with a width of several millimeters on the outer periphery of a wafer to be a substrate is not used as a chip. However, in the manufacturing process, when various thin films are formed by CVD or sputtering, the film is often formed up to the wafer edge portion, bevel portion, and back surface edge portion. Since the film formed on the outer periphery of the wafer is different in thickness from the center part and stress is applied, it comes into contact with various things during subsequent transport and handling, and in the subsequent process The film on the outer peripheral portion peels off due to stress such as heat, and the film becomes particles, which decreases the yield. In particular, as the integration and miniaturization of system LSIs and memories in recent years have progressed, the reduction in yield due to particles has become a major issue, and the management of the wafer outer periphery has become very important. Among them, an EBR (Edge Bevel Removal) process for removing an unnecessary film having a wafer outer peripheral portion of several millimeters has attracted much attention for the purpose of improving the yield.

On the other hand, the film on the wafer is not limited to a single layer, and an organic film such as a photoresist is laminated on an inorganic film such as a SiO ₂ film. However, the reaction form differs between the organic film and the inorganic film, and the removal process cannot be performed simultaneously in one reaction. Therefore, the organic film on the surface layer is first removed, and then the inorganic film is removed. The organic film is generally removed by a wet method using an organic solvent or a dry method by low pressure ashing. In the case where the wet method is adopted, it is then transported to a chamber for removing the inorganic film through a drying process. When a dry method such as low-pressure ashing is adopted, the inside of the chamber for removing the organic film is returned to atmospheric pressure, and then the wafer is taken out from the chamber and transferred to the chamber for removing the inorganic film. The inorganic film is removed by fluorine plasma etching or the like.
JP 63-307200 A Japanese Patent Laid-Open No. 2-100319 Japanese Patent Laid-Open No. 2-114529 JP-A-5-82478 JP-A-8-279494 JP-A-10-189515

  However, a device for removing the organic film and a device for removing the inorganic film are required separately, and not only the device configuration becomes large, but also when transferring from the device for removing the organic film to the device for removing the inorganic film. There is also a possibility of generating particles. Further, in addition to the time for the transfer, setting such as centering in each removing device takes double, and the throughput is deteriorated.

The present invention is a method for removing the first film and the second film on the outer peripheral portion of a base material on which a first film and a second film having different film types are laminated,
The substrate is supported on one stage continuously during the removal process of the first film and the second film, and the stage is rotated relative to the first processing head and the second processing head arranged on the side thereof. However, the first reactive gas for removing the first film is supplied from the first processing head to the outer periphery of the base material, and the second reactive for removing the second film from the second processing head. Supplying gas to the outer periphery of the base material is not claimed .
Further, an apparatus for removing the first film and the second film on the outer peripheral portion of the base material on which the first film and the second film having different film types are laminated,
A first processing head for supplying a first reactive gas for removing the first film to the outer periphery of the substrate;
A second processing head for supplying a second reactive gas for removing the second film to the outer periphery of the substrate;
A stage that supports the substrate continuously during the removal period of the first film and the second film and is rotated relative to the first and second processing heads;
It is the feature which does not claim that it was provided.
As a result, the apparatus configuration and the EBR process can be simplified, the generation of particles can be further prevented, and the throughput can be improved. Moreover, the problem of cross contamination can be avoided by using a different head for each gas type.
The present invention is an apparatus for removing the first film and the second film on the outer periphery of a base material on which a first film and a second film having different film types are laminated,
A first processing head for supplying a first reactive gas and heat for removing the first film to the outer periphery of the substrate;
A second processing head for supplying a second reactive gas for removing the second film to the outer periphery of the substrate;
A stage that continuously supports the substrate during the removal period of the first film and the second film and is relatively rotated about a central axis with respect to the first and second processing heads;
With
A cooling stage for cooling the base material is incorporated into the stage, and a first stage portion slightly smaller in diameter than the base material, and a direction smaller than the first stage portion and in the direction along the central axis with respect to the first stage portion. Has a second stage part that can be projected and stored in
When removing the first film by the first processing head, the first stage unit accommodates the second stage unit and supports the base material,
At the time of removing the second film by the second processing head, the second stage portion protrudes from the first stage portion and supports the base material, and the second processing head includes the protruding second stage portion. A guide path extending in the circumferential direction is provided so as to wrap around the front surface, end surface and back surface of the outer peripheral portion of the base material supported by the support, and the second reactive gas is passed in the extending direction of the guide path. It is characterized by

For example, the first film is an organic film, and the first reactive gas has reactivity with the organic film under heating. The heating temperature is desirably 100 ° C. or higher. The first processing head preferably supplies heat to the outer peripheral portion of the base material in addition to the first reactive gas. Thereby, the reaction rate of the organic film can be increased, and the removal efficiency can be increased.
The second film is an inorganic film, and the second reactive gas has reactivity with the inorganic film. This reaction is performed, for example, at normal temperature or lower than the reaction temperature between the first reactive gas and the organic film (for example, 10 to 80 ° C.).
On the other hand, the first reactive gas hardly reacts with the inorganic film, and the second reactive gas hardly reacts with the organic film.
The organic film, for example, _C m _H n _O l such as a photoresist or polymer (m, n, l is an integer) are composed of organic materials is represented by.
Inorganic membranes, for _example, are constituted by SiO 2, SiN, poly-Si , low-k film or the like.
The first reactive gas having reactivity with the organic film is preferably a gas containing oxygen, and more preferably a gas containing a highly reactive oxygen system such as oxygen radical or ozone. Ordinary pure oxygen gas or air that has not been radicalized or ozonized may be used as it is as the first reactive gas. Oxygen radicals and ozone can be generated using a plasma discharge device or an ozonizer using oxygen (O ₂ ) as a source gas. The organic film is more reactive with the first reactive gas when heated.
A fluorine radical etc. are mentioned as a main component of the 2nd reactive gas which has the reactivity with an inorganic film | membrane. The fluorine radical can be generated using a plasma discharge apparatus using a fluorine-based gas such as PFC gas including CF ₄ and C ₂ F ₆ and HFC including CHF ₃ as a base gas.
As the above oxygen or fluorine plasma discharge device, it is desirable to use an atmospheric pressure (normal pressure) plasma discharge device that causes plasma discharge such as glow discharge under a substantially atmospheric pressure (approximately normal pressure). Here, “substantially atmospheric pressure” refers to a range of 1.013 × 10 ^{4 to} 50.663 × 10 ⁴ Pa. In consideration of facilitation of pressure adjustment and simplification of the apparatus configuration, preferably 1. 333 × a ¹⁰ 4 ^~10.664 × ¹⁰ 4 Pa, more preferably from ^{9.331 × 10 4 ~10.397 × 10 4} Pa.

It is desirable that the first processing head and the second processing head are respectively arranged around the stage.
Accordingly, the first film removal and the second film removal can be performed continuously or concurrently.

It is desirable that the first processing head and / or the second processing head can be moved back and forth between a retracted position away from the stage and a processing position where the removal processing is performed.
Accordingly, it is possible to prevent the first processing head from interfering when the substrate is placed on the stage or taken out or during the second film removal process. Alternatively, it is possible to prevent the second processing head from interfering when the substrate is placed on the stage or taken out, or during the first film removal process.
In the above-mentioned claim, the second processing head is advanced and retracted between a retracted position separated from the outer peripheral edge of the first stage portion on the side opposite to the central axis and a position at the time of removing the second film. It is preferable to provide an advance / retreat mechanism.

It is desirable that the first processing head is provided with an irradiation unit that irradiates the outer peripheral portion of the base material with radiant heat locally.
Accordingly, only the first film on the outer peripheral portion of the base material can be heated and removed, heat can be prevented from reaching the inner main portion from the outer peripheral portion, and alteration of the main portion film can be prevented. Further, since it can be heated in a non-contact manner, particle generation can be prevented.

The first processing head includes a blowing nozzle (blowing part) for blowing the first reactive gas to the local area (irradiation spot), and a suction nozzle (suction part) for sucking gas in the vicinity of the blowing nozzle. It is desirable to be provided.
Thus, the flow of the first reactive gas can be controlled, and the first film on the outer peripheral portion of the base material can be reliably removed while avoiding influence on the main portion inside the outer peripheral portion as much as possible.
It is desirable that the blowout nozzle and the suction nozzle are arranged at positions that do not block the heat beam from the irradiation unit. You may comprise a blowing nozzle or a suction nozzle with a translucent material.
You may arrange | position a blowing nozzle and a suction nozzle so that it may oppose substantially along the tangent of a base material. The irradiation spot may be positioned between the blowing nozzle and the suction nozzle.

It is preferable that the second processing head is provided with a guide path extending in the circumferential direction so as to wrap around the outer peripheral portion of the base material, and the second reactive gas is passed in the extending direction of the guide path.
Thus, the second film on the outer peripheral portion of the substrate can be reliably removed while avoiding the influence on the main portion inside the outer peripheral portion as much as possible.
In the above-mentioned claim, the insertion hole into which the outer peripheral portion of the base material is inserted into the second processing head is directed from the end surface facing the central axis of the second processing head toward the inside of the second processing head. It is preferable that the end portion on the inner side of the insertion port is wider than the portion on the end face side to form the guide path.

It is desirable that cooling means for cooling the substrate is incorporated in the stage.
As a result, when the outer peripheral portion of the substrate is heated by the irradiation unit during the removal of the first film, even if the heat is transmitted to the main portion inside the outer peripheral portion of the substrate, the heat can be absorbed by the cooling means, It is possible to prevent the main portion from increasing in temperature, and thus to prevent the first film and the second film of the main portion of the base material from deteriorating.
The stage incorporates a cooling means for absorbing and cooling the base material, and has a first stage portion slightly smaller in diameter than the base material, and has a smaller diameter than the first stage portion and protrudes in the axial direction with respect to the first stage portion. -Having a second stage portion provided so that it can be stored;
When removing the first film by the first processing head, the first stage unit accommodates the second stage unit and supports the base material,
When the second film is removed by the second processing head, it is preferable that the second stage portion protrudes from the first stage portion and supports the substrate.
Thereby, it is possible to prevent the second processing head from interfering with the first stage unit. As a result, the amount of insertion of the second processing head into the base material can be increased, and the second reactive gas can be prevented from flowing to the main portion inside the outer peripheral portion of the base material. On the other hand, the diameter of the first stage portion can be made sufficiently large, and the cooling means can reliably cool the vicinity of the outer peripheral portion of the substrate. As a result, it can prevent more reliably that the film quality of the main part of a base material is impaired.

A common plasma discharge device that is selectively supplied with a first source gas and a second source gas and is selectively connected to the first processing head and the second processing head;
When the first source gas is selected, the first reactive gas is generated from the first source gas by plasma discharge between the electrodes of the common plasma discharge device and supplied to the first processing head.
When the second source gas is selected, it is preferable that the second reactive gas is generated from the second source gas by the plasma discharge and supplied to the second processing head.
As a result, the first and second reactive gases can be generated by a common plasma discharge apparatus, and the apparatus configuration can be simplified.

While the stage is stationary, the first and second processing heads may be rotated around the stage, but the stage is rotated while the first and second processing heads are stationary. It is desirable. The wafer is rotated by the rotation of the stage, whereby excellent uniformity can be obtained without using a mask. For example, in the case of etching processing of a photoresist (film thickness: 1 μm), a uniformity of ± 0.1 mm can be obtained with respect to a processing width of 2 mm.
It is desirable that the relative rotational speed of the stage can be adjusted. As a result, the rotational speed can be made different between the removal of the first film and the removal of the second film, and an appropriate rotational speed can be obtained according to the processing content.

  According to the present invention, the first film and the second film of the base material can be removed on a common stage, the apparatus configuration can be simplified, the generation of particles can be further prevented, and the throughput can be further reduced. Can be improved.

Embodiments of the present invention will be described below.
First, the wafer 90 (base material) to be processed will be described. As shown by the phantom lines in FIG. 1, the wafer 90 has a disk shape. The diameter is, for example, about 200 mm. As shown in FIG. 8A, an inorganic film 94 such as SiO ₂ is coated on the front side surface (upper surface) of the wafer 90, and an organic film 93 such as a photoresist is coated thereon. These films 93 and 94 extend not only to the main portion 91 inside the outer peripheral portion 92 on the upper surface of the wafer 90 but also to the outer peripheral portion 92.
The organic film 93 constitutes the “first film” in the claims, and the inorganic film 94 constitutes the “second film”.
The substrate outer periphery processing apparatus 1 of the present invention removes the organic film 93b and the inorganic film 94b in the outer peripheral portion 92 while leaving the organic film 93a and the inorganic film 94a in the main portion 91 of the wafer 90 (FIG. 8 ( c)).

As shown in FIG. 1, the substrate outer periphery processing apparatus 1 according to the first embodiment of the present invention that is not claimed includes one (single) common chamber 2. The inside of the chamber 2 is at atmospheric pressure. In the chamber 2, a first processing head 10 for removing an organic film, a second processing head 20 for removing an inorganic film, and a stage 30 common to these heads 10 and 20 are provided.

  As shown in FIGS. 1 and 2, the stage 30 has a disk shape. A wafer 90 is placed horizontally on the upper surface of the stage 30. The wafer 90 is aligned by the alignment mechanism 3 composed of a manipulator or the like so that the stage 30 and the axis coincide with each other. The stage 30 incorporates an electrostatic chuck type or vacuum suction type adsorption mechanism (not shown) for fixing the aligned wafer 90 so as not to be displaced.

  The diameter of the stage 30 is slightly smaller than the diameter of the wafer 90. As a result, the outer peripheral portion 92 of the wafer 90 slightly protrudes from the outer edge of the stage 30. For example, while the diameter of the wafer 90 is 200 mm, the diameter of the stage 30 is 194 mm, and the outer peripheral portion 92 of the wafer 90 protrudes from the outer edge of the stage 30 by 3 mm.

The stage 30 is rotated around the central axis L30 by a rotation mechanism 39. The rotation speed by the rotation mechanism 39 can be adjusted.
The first processing head 10 and the second processing head 20 may be rotated around the stage 30 while the stage 30 is stationary.

The stage 30 incorporates endothermic cooling means for absorbing and cooling the wafer 90. That is, the inside of the stage 30 is a cavity, and this cavity is the cooling chamber 33. The cooling chamber 33 extends over the entire area of the stage 30 (the entire circumference in the circumferential direction and the whole in the radial direction). The cooling chamber 33 is filled with a cooling fluid such as air or water from a supply path 34. The cooling fluid in the cooling chamber 33 can be discharged through the discharge path 35. A new cooling fluid is supplied from the supply path 34 along with the discharge. The cooled cooling fluid may be cooled and re-supplied to the cooling chamber 33.
At least the upper plate of the stage 30 (the plate on the side where the wafer 90 is installed) is made of a material having good thermal conductivity (for example, aluminum).

  The first processing head 10 for removing the organic film is disposed on one side of the stage 30 in the circumferential direction. As indicated by white arrows in FIG. 2, the first processing head 10 is connected to the first advance / retreat mechanism 13. By this first advance / retreat mechanism 13, the first processing head 10 moves the processing position along the outer peripheral portion 92 of the wafer 90 (the phantom line in FIGS. 1 and 2) and the retracted position away from the wafer 90 radially outward (see FIG. 1 and the solid line in FIG. 2).

  As shown by a solid line and a two-dot chain line in FIG. 2, the first processing head 10 is arranged above a horizontal plane on which the wafer 90 is to be arranged. Instead, as shown by a three-dot chain line in FIG. Further, it may be arranged below the wafer arrangement surface. Alternatively, a pair may be provided on the upper and lower sides of the wafer placement surface. By disposing the processing head 10 on the upper side, the outer peripheral portion 92 mainly on the upper surface (front side surface) of the wafer 90 can be processed. On the other hand, if arranged below, the outer peripheral portion 92 of the lower surface (back surface) of the wafer 90 can be processed.

  As shown in FIGS. 3 and 4, the first processing head 10 is provided with an irradiation section 42 of a radiant heating means and a pair of nozzles 11 and 12. The radiant heating means includes a radiant heat light source such as a laser source 40, and a transmission optical system 41 such as an optical fiber cable extends from the radiant heat light source 40 and is connected to the irradiation unit 42. Although not shown, the irradiating unit 42 is provided with condensing means such as a lens and a parabolic reflector, and an exit window. The laser light transmitted from the laser source 40 through the optical fiber cable 41 is emitted from the emission window while being condensed by the condensing means. When the first processing head 10 is at the processing position, the emitted light L40 is locally irradiated to one location 92p of the outer peripheral portion 92 of the wafer 90 on the stage 30.

  As shown in FIG. 3, the pair of nozzles 11, 12 of the first processing head 10 are arranged close to each other so as to face each other with the irradiation portion 92 p sandwiched substantially along the tangent line of the wafer 90 at the processing position. These nozzles 11 and 12 are formed of an ozone resistant material.

  The first reactive gas for removing the organic film reacts with an organic substance such as a photoresist, and ozone is used here. An ozonizer 50 is used as the first reactive gas generation source. Note that an oxygen plasma discharge device may be used in place of the ozonizer 50. A first reactive gas supply path 51 extends from the first reactive gas generation source 50 and is connected to the blowing nozzle 11 (blowing part). A first treated gas suction path 52 extends from a suction nozzle 12 (suction unit) facing the blowout nozzle 11 and is connected to a first suction means 53 including a suction pump.

  As shown in FIG. 1, the second processing head 20 is disposed at a portion 180 degrees opposite to the first processing head 10 side of the stage 30. As shown by the white arrow in FIG. 2, the second processing head 20 is connected to the second advance / retreat mechanism 23. The second advance / retreat mechanism 23 causes the second processing head 20 to move the processing position along the outer peripheral portion 92 of the wafer 90 (virtual line in FIG. 2) and the retreat position away from the wafer 90 radially outward (solid line in FIG. 2). ) Can move forward and backward.

  As shown in FIG. 5, the second processing head 20 has a substantially arc shape along the outer periphery of the wafer 90. As shown in FIG. 7, the insertion port 21 is formed in a cut shape toward the inside of the second processing head 20 on the peripheral surface on the small diameter side of the second processing head 20. As shown in FIGS. 5 and 6, the insertion port 21 extends over the entire circumferential length of the second processing head 20. The thickness of the insertion slot 21 in the vertical direction is slightly larger than the thickness of the wafer 90. The outer peripheral portion 92 of the wafer 90 is inserted into and removed from the insertion slot 21 by the advance / retreat operation of the second processing head 20.

  As shown in FIG. 7, the rear end of the insertion port 21 is greatly expanded to form a second reactive gas guide path 22. As shown in FIG. 5, the guide path 22 extends in the longitudinal direction (circumferential direction) of the second processing head 20 and has a circular arc shape in plan view with a radius of curvature substantially the same as the radius of the wafer 90. When the wafer 90 is inserted into the insertion slot 21, the outer peripheral portion 92 of the wafer 90 is positioned inside the guide path 22. As shown in FIG. 7, the cross-sectional shape of the guide path 22 is a perfect circle, but is not limited thereto, and may be a semicircle or a quadrangle, for example. Moreover, you may set the flow-path cross-sectional area of the guide path 22 to a suitable magnitude | size.

The second reactive gas for removing the inorganic film reacts with an inorganic substance such as SiO ₂ , and as its source gas, for example, P ₄ gas including CF ₄ and C ₂ F ₆ and HFC including CHF ₃ are used. Fluorine-based gas such as is used. As shown in FIG. 6, this fluorine-based gas is introduced into an atmospheric pressure plasma discharge space 61a between a pair of electrodes 61 of a fluorine plasma discharge device 60 as a second reactive gas generation source to be converted into plasma, and fluorine radicals or the like The second reactive gas containing the fluorine-based active species is obtained. A second reactive gas supply path 62 extends from the atmospheric pressure plasma discharge space 61 a and is connected to one end of the guide path 22 of the second processing head 20. A discharge path 63 extends from the other end of the guide path 22.
The second processing head 20 is made of a fluorine resistant material.

A method for removing an unnecessary film on the outer periphery of the wafer 90 by the substrate outer periphery processing apparatus 1 having the above configuration will be described.
[Organic film removal process]
First, the removal process of the organic film 93b on the outer peripheral portion 92 of the wafer 90 is performed. Both the first and second processing heads 10 and 20 are retracted to the retracted position. Then, the wafer 90 to be processed is centered and set on the stage 30 by the alignment mechanism 3. Next, the first processing head 10 is advanced to the processing position. As a result, the irradiation unit 42 is directed to one location 92p of the outer peripheral portion 92 of the wafer 90, and the blowing nozzle 11 and the suction nozzle 12 face each other in the tangential direction of the wafer 90 with the location 92p interposed therebetween. The second processing head 20 is left in the retracted position as it is.

  Then, the laser source 40 is turned on. Thereby, the laser from the laser source 40 is emitted from the irradiation unit 42 through the optical fiber cable 41. This laser is locally irradiated to one portion 92p of the outer peripheral portion 92 of the wafer 90, and this portion 92p is locally heated and instantaneously becomes high temperature. By adjusting the focal length or the like of the irradiation unit 42, the spot diameter of the irradiation point 92p can be controlled. As a result, the width of the film 93b to be removed can be controlled. Moreover, since it is radiation heating, the to-be-heated location 92p and a heating means do not contact, and generation | occurrence | production of a particle can be prevented.

  In addition, oxygen-based reactive gas such as ozone generated by the ozonizer 50 is blown out from the blowing nozzle 11 of the first processing head 10. This reactive gas is sprayed in a limited manner on the local portion 92p of the outer peripheral portion 92 of the wafer 90. As a result, as shown in FIG. 8B, the local 92p organic film 93b undergoes an oxidation reaction and is etched (ashed). The treated gas containing the incinerated organic film soot can be quickly removed by suction with the suction nozzle 12.

Since the local 92p is sufficiently heated by laser heating, the reaction rate can be increased and high ashing efficiency can be obtained.
On the other hand, since the laser heating is spot-like, it is possible to prevent the temperature of the portion other than the local 92p of the wafer 90 from increasing. Further, even when the heat of the local 92p is transmitted toward the inside of the wafer 90, the heat is absorbed by the cooling fluid in the stage 30. As a result, the main portion 91 of the wafer 90 can be prevented from being heated and heated, and the organic film 93a of the main portion 91 can be reliably prevented from being deteriorated by the influence of heat. Further, since the organic film 93a of the main portion 91 of the wafer 90 is not heated, it is possible to prevent ashing even if it is in contact with an oxygen-based reactive gas such as ozone. Furthermore, gas diffusion into the main portion 91 of the wafer 90 can be prevented by adjusting the flow rate of the reactive gas.

  FIG. 9 shows an example of the measurement result of the temperature distribution around the laser irradiation spot 92p on the outer periphery of the wafer when the organic film is removed. The horizontal axis is the distance from the outer edge of the wafer 90 to the radially inward direction. As can be seen from the figure, the area of 2 to 3 mm from the outer edge of the wafer became extremely high at a maximum of about 400 ° C., but the temperature suddenly decreased from 100 ° C. . FIG. 10 shows the substrate temperature dependence of the etching rate of the organic film by atmospheric pressure plasma. As can be seen from the figure, a high etching rate was exhibited at 300 ° C. or higher, but almost no etching was performed at 100 ° C. or lower. As a result, it has been found that even if the main portion 91 of the wafer 90 is coated with an organic film such as a photoresist, alteration due to heat can be reliably prevented. In addition, FIG. 10 is measured without rotating the wafer.

  In parallel with the laser and ozone irradiation, the stage 30 is rotated. This rotational speed is, for example, about 10 rpm. Thereby, the to-be-processed location of the outer peripheral part 92 of the wafer 90 can be extended in the circumferential direction. By rotating the stage 30 one or more times, the organic film 93b on the outer periphery 92 of the wafer 90 can be ashed and removed over the entire periphery. As a result, the inorganic film 94b on the outer peripheral portion 92 of the wafer 90 is exposed over the entire periphery.

[Inorganic film removal process]
Next, a step of removing the inorganic film 94b on the wafer outer peripheral portion 92 is performed. At this time, the wafer 90 is left set on the stage 30. Then, the second processing head 20 is advanced, and the outer peripheral portion 92 of the wafer 90 is inserted into the insertion port 21. As a result, a certain length of the outer peripheral portion 92 of the wafer 90 is wrapped in the guide path 22. By adjusting the insertion amount, the width (process width) of the film 94b to be removed can be easily controlled.

Next, a fluorine-based gas such as CF ₄ is supplied to the interelectrode space 61a of the fluorine-based plasma discharge device 60, and an electric field is applied between the electrodes 61 to generate atmospheric pressure glow discharge plasma. Thereby, the fluorine-based gas is activated and a second reactive gas composed of fluorine radicals or the like is generated. The second reactive gas is guided to the guide path 22 of the second processing head 20 through the supply path 62 and flows along the guide path 22 in the circumferential direction of the outer peripheral portion 92 of the wafer 90. As a result, as shown in FIG. 8C, the inorganic film 94b on the outer peripheral portion 92 of the wafer 90 can be etched and removed. The treated gas containing etching by-products is exhausted from the exhaust path 63. Moreover, since the insertion port 21 is narrowed, the diffusion of the second reactive gas to the main portion 91 of the wafer 90 can be prevented. In addition, the diffusion of the second reactive gas to the main portion 91 can be more reliably prevented by adjusting the flow rate of the second reactive gas.

At the same time, the stage 30 is rotated. Thus, the inorganic film 94b on the outer peripheral portion 92 of the wafer 90 can be etched and removed over the entire periphery. The rotation speed at this time is faster than that at the time of removing the organic film 93b, for example, about 100 rpm.
The etching rate of the inorganic film 94b is slower as the crystallinity / density of the film 94b is higher, and is faster as the crystallinity / density is lower.

  Note that the first processing head 10 may be retracted to the retracted position after the organic film removing process is finished and before the inorganic film removing process is started, or may be retracted after the inorganic film removing process is finished. When the organic film 93b can be removed at the first rotation of the stage 30, the inorganic film may be removed concurrently with the organic film removal. When the inorganic film 94b starts to be partially exposed during the organic film removal process, the inorganic film removal process may be performed in parallel with the organic film removal.

When the inorganic film component is, for example, SiN, a residue such as (NH ₄ ) 2 SiF ₆ , NH ₄ F · HF, that is, a solid by-product at room temperature is formed by etching. Therefore, in this case, during the inorganic film removing step, the first processing head 10 is positioned at the processing position, and laser irradiation to the outer peripheral portion 92 of the wafer 90 is continued by the radiation heating means. Thereby, the solid by-product can be vaporized at the normal temperature. Furthermore, by driving the first suction means 53, the vaporized by-product can be sucked and discharged from the suction nozzle 12.

  After the inorganic film removing step, the heads 10 and 20 are retracted to the retracted position and the rotation of the stage 30 is stopped. Then, the chucking of the wafer 90 by the chuck mechanism in the stage 30 is released, and the wafer 90 is unloaded.

  According to the present invention, the wafer 90 is continuously set on the stage 30 throughout the entire period of the organic film removing process and the inorganic film removing process. Therefore, it is not necessary to transfer the wafer 90 to another place when shifting from the organic film removing process to the inorganic film removing process, and the transfer time can be omitted. Further, particles are not generated by touching the transfer cassette during transfer. Furthermore, re-alignment becomes unnecessary. As a result, the overall processing time can be greatly shortened, the throughput can be improved, and high-accuracy processing can be performed. In addition, the alignment mechanism 3 and the stage 30 can be shared, and the apparatus configuration can be simplified and made compact. By installing a plurality of processing heads 10 and 20 in one common chamber 2, various film types can be handled. Furthermore, the problem of cross contamination can be avoided. In addition, since the present invention is a normal pressure system, the drive portion and the like can be easily stored in the chamber 2.

Next, another embodiment of the present invention will be described. In the following embodiments, the same reference numerals are given to the drawings for the same configurations as those in the first embodiment, and the description thereof is omitted.
FIG. 11 shows a second embodiment claimed in the present invention . The stage 30 of this embodiment has a nested structure with a first stage portion 31 and a second stage portion 32. The first stage portion 31 has a disk shape slightly smaller in diameter than the wafer 90, and an accommodation recess 31a is formed on the upper surface thereof.

  The second stage portion 32 has a disk shape with a diameter much smaller than that of the first stage portion 31, and is disposed on the same axis L30 as the first stage portion 31. A lift mechanism 36 (an axial slide mechanism) is connected to the second stage portion 32. The lifting mechanism 36 causes the second stage portion 32 to protrude upward from the first stage portion 31 (FIG. 11B), and the storage position stored in the storage recess 31a of the first stage portion 31 (see FIG. It can be moved up and down with respect to FIG. In addition, while the 2nd stage part 32 is fixed, the 1st stage part 31 is connected to the raising / lowering mechanism 36, and it raises / lowers, As a result, the 2nd stage part 32 may protrude and store. . The upper surface of the second stage unit 32 in the storage position is flush with the upper surface of the first stage unit 31, but may be recessed below the upper surface of the first stage unit 31.

Although not shown, the first stage unit 31 and the second stage unit 32 each have a chucking mechanism for the wafer 90 built therein.
The inside of the first stage portion 31 is a cooling chamber 33. Although the cooling means including the cooling chamber 33 is provided only in the first stage portion 31, it may be provided also in the second stage portion 32.

  The second processing head 20 is positioned at the height of the upper surface of the second stage portion 32 at the protruding position.

  As shown in FIG. 11A, in the organic film removing step, the cooling unit is operated and the first stage unit 31 and the second stage unit 32 are rotated while the second stage unit 32 is located at the storage position. Processing is performed by the first processing head 10 while being integrally rotated around a common axis by the mechanism 39.

As shown in FIG. 11B, after the organic film removal process is completed, the first processing head 10 is retracted to the retracted position. Next, the second stage unit 32 is raised by the lifting mechanism 36 and is positioned at the protruding position. Thereby, the wafer 90 can be separated above the first stage unit 31.
Then, the second processing head 20 is advanced from the retracted position to the processing position, and the inorganic film removing step is executed. Since the wafer 90 is separated above the first stage portion 31, it is possible to avoid interference between the outer peripheral portion 92 of the first stage portion 31 and the lower side portion of the second processing head 20. As a result, the depth of the insertion opening 21 along the radial direction of the wafer 90 can be increased. As a result, the diffusion of the second reactive gas into the main portion 91 of the wafer 90 can be more reliably prevented.
On the other hand, the diameter of the first stage portion 31 can be sufficiently increased, and the cooling means can reliably cool the vicinity of the outer peripheral portion of the wafer 90. As a result, it is possible to more reliably prevent the film quality of the main portion 91 of the wafer 90 from being damaged.
In this inorganic film removing step, only the second stage unit 32 needs to be rotated by the rotation mechanism 39. Thus, the inorganic film 94b on the outer peripheral portion 92 of the wafer 90 can be etched and removed over the entire periphery.

FIG. 12 shows a third embodiment of the present invention which is not claimed . In this embodiment, the first reactive gas and the second reactive gas are generated by a common plasma discharge device 70. Oxygen (O ₂ ) is used as the source gas of the first reactive gas. A fluorine-based gas such as CF ₄ is used as the source gas of the second reactive gas. The source gas supply paths 73 and 74 from the source gas sources merge with each other and extend to the atmospheric pressure plasma discharge space 71 a between the pair of electrodes 71 of the common plasma discharge device 70. Each source gas supply path 73, 74 is provided with on-off valves 73V, 74V.

  The reactive gas supply path 75 from the common plasma discharge device 70 is divided into two hands, a first reactive gas supply path 51 and a second reactive gas supply path 62, via a three-way valve 76. The first reactive gas supply path 51 is continuous with the blowing nozzle 11 of the first processing head 10. The second reactive gas supply path 62 is continuous with the upstream end of the guide path 22 of the second processing head 20.

  In the organic film removal step, the on-off valve 74V of the second source gas supply path 74 is closed, while the on-off valve 73V of the first source gas supply path 73 is opened. As a result, the first source gas (oxygen gas) is introduced into the discharge space 71a of the plasma discharge device 70 and activated, and a first reactive gas such as oxygen radical or ozone is generated. Further, the common reactive gas supply path 75 from the plasma discharge device 70 is connected to the first reactive gas supply path 51 by a three-way valve 76. As a result, the first reactive gas such as ozone is introduced into the blowing nozzle 11 of the first processing head 10, and the organic film 93 b on the outer peripheral portion 92 of the wafer 90 can be ashed and removed.

In the inorganic film removing step, the on-off valve 73V of the first source gas supply path 73 is closed while the on-off valve 74V of the second source gas supply path 74 is opened. As a result, the second source gas (fluorine-based gas such as CF ₄ ) is introduced into the plasma discharge device 70 to be converted into plasma, and a second reactive gas such as F ^* is generated. Further, the common reactive gas supply path 75 from the plasma discharge device 70 is connected to the second reactive gas supply path 62 by a three-way valve 76. As a result, the second reactive gas such as fluorine radicals is introduced into the guide path 22 of the second processing head 20 and flows in the circumferential direction of the wafer 90, and the inorganic film 94 b on the outer peripheral portion 92 of the wafer 90 is etched and removed. Can do.

  13 and 14 show a modification of the endothermic cooling means provided on the stage 30. FIG. This endothermic cooling means is provided only on the outer periphery of the stage 30. That is, an annular partition wall 37 is provided concentrically inside the stage 30. The stage 30 is divided into an outer peripheral region 30Ra and a central region 30Rb by the annular partition wall 37.

A refrigerant supply path 34 and a refrigerant discharge path 35 are connected to the outer peripheral region 30Ra outside the annular partition wall 37. Thereby, the inside of the outer peripheral region 30Ra is a refrigerant chamber 33 (heat absorption means).
On the other hand, the inner peripheral region 30Rb inside the annular partition wall 37 is not a refrigerant chamber, and is a non-arranged portion of the endothermic cooling means.

The outer peripheral portion of the wafer 90 protrudes radially outward from the outer peripheral region 30Ra of the stage 30. An annular portion immediately inside the projecting portion is abutted and supported by the outer peripheral region 30Ra of the stage 30, and a central portion inside the projecting portion is abutted and supported by the central region 30Rb of the stage 30.
As a result, the heat from the heated portion on the outer peripheral portion of the wafer 90 is absorbed and removed in the stage outer peripheral region 30Ra when it is transferred to the inner portion. On the other hand, the portion not related to the heat transfer at the center of the wafer 90 is not endothermic cooled. This can save the endothermic cooling source.

As shown by a solid line in FIG. 14, the irradiation unit 42 of the radiant heating means is provided above the wafer 90. As a result, the front side surface of the outer peripheral portion of the wafer 90 is locally heated, and the reactive gas is supplied thereto from the blowing nozzle 11 of the first reactive gas supply means, whereby the unnecessary film on the front side surface of the outer peripheral portion of the wafer 90 is obtained. Is supposed to be removed. As shown by phantom lines in FIG. 14, when the unnecessary film on the back surface of the outer peripheral portion of the wafer 90 is removed, the irradiation section 42 of the radiant heating means is disposed below the wafer 90.
The 2nd stage part 32 which can be raised / lowered is arrange | positioned only in inner peripheral area | region 30Rb.

The present invention is not limited to the above embodiment, and various modifications can be made.
The separation angle between the first processing head 10 and the second processing head 20 is not limited to 180 degrees, and may be 120 degrees or 90 degrees.
The first processing head 10 and the second processing head 20 may not interfere with each other in the retracted position and the advance / retreat operation, and the processing positions may overlap.
A plurality of first processing heads 10 may be arranged apart from each other in the circumferential direction of the stage 30. Similarly, a plurality of second processing heads 20 may be arranged apart from each other in the circumferential direction of the stage 30.
The first processing head 10 may be integrally attached to the first reactive gas generation source, and the second processing head 20 may be integrally attached to the second reactive gas generation source.
The irradiation unit 42 of the radiant heating means and the first reactive gas blowing nozzle 11 may be moved forward and backward separately.
As a wafer cooling means (heat absorption means) incorporated in the stage 30, instead of making the inside of the stage 30 hollow, a pipe line through which a cooling fluid passes may be accommodated in the stage 30. A Peltier element may be built in the stage 30.
When the organic film 93 and the inorganic film 94 are laminated in this order on the wafer 90 from the bottom, the inorganic film removing process is first performed, and then the organic film removing process is performed.

  The present invention can be applied, for example, to a process of removing unnecessary organic films and inorganic films coated on the outer peripheral portion in the manufacture of a semiconductor wafer.

It is a plane explanatory view showing a schematic structure of a substrate perimeter treatment device concerning a 1st embodiment of the present invention. It is front explanatory drawing of the said base-material outer periphery processing apparatus. It is a plane sectional view of the 1st processing head of the above-mentioned substrate perimeter processing device. FIG. 4 is a side sectional view of the first processing head taken along line IV-IV in FIG. 3. It is a top view of the 2nd processing head of the above-mentioned substrate perimeter processing device. FIG. 6 is a cross-sectional view of the second processing head developed in the circumferential direction (longitudinal direction) along line VI-VI in FIG. 5. It is sectional drawing of the said 2nd processing head which follows the VII-VII line of FIG. It is an expanded sectional view of the perimeter part of a wafer, (a) shows the state before removal processing of an organic film and an inorganic film, (b) shows the state before organic film removal after organic film removal, (c) The state after the removal process of an organic film and an inorganic film is shown. It is a graph which shows the measurement result of the temperature distribution around the local irradiation location of a wafer outer peripheral part at the time of organic film removal. It is a graph which shows the measurement result of the substrate temperature dependence of the etching rate of the organic film by a normal pressure plasma. It is front explanatory drawing which shows schematic structure of the base material outer periphery processing apparatus which concerns on 2nd Embodiment of this invention in the state of an organic film removal process. It is front explanatory drawing which shows schematic structure of the base-material outer periphery processing apparatus which concerns on the said 2nd Embodiment in the state of an inorganic film removal process. It is a schematic block diagram of the base-material outer periphery processing apparatus which concerns on 3rd Embodiment of this invention. It is a top view of the stage in which the heat absorption means was provided only in the outer peripheral area. FIG. 14 is an explanatory side view of the stage and the like in FIG. 13.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate outer periphery processing apparatus 10 1st processing head 11 Blowing nozzle (blowing part)
12 Suction nozzle (suction part)
20 Second processing head 22 Guide path 30 Stage 31 First stage portion 32 Second stage portion 33 Cooling chamber 40 Laser source 42 Irradiation portion 70 Common plasma discharge device 71a Plasma discharge space 90 of common plasma discharge device Wafer (base material)
91 Main part 92 on the inner side of the outer peripheral part of the wafer 92 Outer peripheral part of the wafer 92p Local (irradiation spot) of the outer peripheral part of the wafer
93 Organic film (first film)
94 Inorganic film (second film)

Claims (4)

An apparatus for removing the first film and the second film on the outer periphery of a base material on which a first film and a second film having different film types are laminated,
A first processing head for supplying a first reactive gas and heat for removing the first film to the outer periphery of the substrate;
A second processing head for supplying a second reactive gas for removing the second film to the outer periphery of the substrate;
A stage that continuously supports the substrate during the removal period of the first film and the second film and is relatively rotated about a central axis with respect to the first and second processing heads;
Equipped with a,
A cooling stage for cooling the base material is incorporated into the stage, and a first stage portion slightly smaller in diameter than the base material, and a direction smaller than the first stage portion and in the direction along the central axis with respect to the first stage portion. Has a second stage part that can be projected and stored in
When removing the first film by the first processing head, the first stage unit accommodates the second stage unit and supports the base material,
At the time of removing the second film by the second processing head, the second stage portion protrudes from the first stage portion and supports the base material , and the second processing head includes the protruding second stage portion. A guide path extending in the circumferential direction is provided so as to wrap the surface, end face, and back surface of the outer peripheral portion of the base material supported by the support , and the second reactive gas is passed in the extending direction of the guide path. The substrate outer periphery processing apparatus. In the second processing head, an insertion port into which the outer peripheral portion of the base material is inserted is formed in a cut shape from an end surface facing the central axis of the second processing head toward the inside of the second processing head, 2. The substrate outer peripheral processing apparatus according to claim 1, wherein an end portion on the inner side of the insertion port is expanded from a portion on the end face side to form the guide path. The first film is an organic film, and the first reactive gas has reactivity with the organic film under heating;
The substrate outer periphery treatment apparatus according to claim 1 or 2, wherein the second film is an inorganic film, and the second reactive gas has reactivity with the inorganic film. Said second processing head, wherein the said central axis of the outer periphery of the first stage portion provided with a reciprocating mechanism for advancing and retracting between a position at the time of the second layer is removed and a retracted position away on the other side substrate periphery processing apparatus according to any one of claims 1 to 3, wherein.

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