JP2005340556A - Substrate treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment device capable of suppressing the adhesion of treatment liquid mist to a substrate top. <P>SOLUTION: The substrate treatment device is provided with: a spin chuck 3 for holding and rotating a wafer 2; a chemical blast nozzle 5 for supplying a treatment liquid to the wafer 2 top; a treatment cup 1 arranged so that the side and the lower part of the wafer 2 may be surrounded; and a plurality of steps of cut structures 4 arranged in the inner wall of the treatment cup 1 in parallel to the oblique direction to the wafer 2. The plurality of steps of cut structures 4 can be spirally formed in the inner wall of a container. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a substrate processing apparatus.

  When wiring is formed on a wafer used for a semiconductor device, generally, after forming a resist film on a metal film such as aluminum (hereinafter referred to as coating treatment), the wiring pattern is exposed by a reduction projection exposure apparatus, The exposed portion of the resist is removed by chemical treatment (hereinafter referred to as development processing), and the exposed metal is etched.

  At this time, the substrate processing apparatus having a mechanism for rotating the wafer is mainly used in the coating process and the developing process, but mist generated during the process is likely to be scattered outside the processing unit. The mist scattered outside the processing unit may adhere to the wafer before processing. Alternatively, the mist scattered outside the processing unit may adhere to the wafer after processing ends in the processing unit. The portion to which this mist adheres becomes a defect such as a wiring short circuit or wiring thinning, and tends to cause a decrease in the yield of the semiconductor device.

  Therefore, substrate processing apparatuses having various structures have been developed for the purpose of suppressing mist scattering to the outside of the processing unit. An example of such a conventional substrate processing apparatus is described in Patent Document 1. The substrate processing apparatus described in the document is shown in FIG. The substrate processing apparatus includes a rectifying plate 42 that controls the flow of the processing liquid mist at the top of the processing cup 30.

  More specifically, the substrate processing apparatus includes a spin chuck 20 that rotates while holding the wafer W horizontally, a processing cup 30 that includes a side wall 32 and a bottom wall 31 and has a rotating body-shaped inner wall surface, The processing cup 30 is open upward.

  Further, a cylindrical splash guard 40 that suppresses scattering of the processing liquid from the wafer W is provided above the upper end edge of the cylindrical main body 41 and protrudes substantially linearly inward. It has the baffle plate 42 couple | bonded so that.

  The rectifying plate 42 is a plate-like body along an inverted conical surface that goes downward as it goes inward, and is configured in an annular shape in plan view. The inner edge portion 42 a of the rectifying plate 42 protrudes to a position corresponding to the inner side of the edge portion of the wafer W held by the spin chuck 20. Therefore, the circle formed by the inner edge portion 42 a becomes an opening 43 for introducing a downflow smaller than the opening area of the wafer W.

  Further, an exhaust port 33 is formed in the bottom wall 31, and the amount of downflow air taken into the processing cup is increased by a negative pressure source 37 such as a factory utility or a pump. The downflow 90 in the clean room is guided toward the upper surface of the wafer W through the opening 43. However, in the vicinity of the upper surface of the wafer W, centrifugal force is applied to the air as the wafer W rotates. An outward airflow is generated from the center toward the side wall 32 of the processing cup 30.

  Further, below the spin base 22, centrifugal force is given to the air by the rotation of the spin base 22 itself, and an outward air flow from the rotation center toward the side wall 32 of the processing cup 30 is generated. These outward airflows generate a rising airflow 91 that rises along the side wall 32 and further along the inner wall surface of the splash guard main body 41.

  The path of the rising airflow 91 is changed inward and downward by the lower surface of the rectifying plate 42 at the upper edge of the splash guard 40, and an inward airflow 92 is generated. Further, the downflow 90 is also converted into an inward airflow directed inward and downward of the opening 43 on the upper surface of the rectifying plate 42. Then, the air currents on the upper surface and the lower surface merge with the downflow 90 from above, and are guided toward the upper surface of the wafer W.

  In this substrate processing apparatus, scattering of the processing liquid mist to the outside of the processing chamber 50 can be suppressed by the above-described action of the rectifying plate 42 provided on the upper portion of the processing cup 30.

  Moreover, as a conventional liquid processing apparatus, there is one described in Patent Document 2. Patent Document 2 discloses a liquid processing apparatus in which a large number of outlets and flow paths are provided in order to shake off the liquid on the side of the case.

Moreover, as a conventional thin film coating apparatus, there is one described in Patent Document 3. Patent Document 3 discloses a thin film coating apparatus in which a shielding plate provided with a plurality of holes in a case inner wall is arranged in a multilayer structure.
Japanese Patent Laid-Open No. 11-042460 JP 2000-153209 A JP-A-1-248619

  However, in the prior art described in the above document, since the processing liquid mist is likely to rise to a position above the surface of the semiconductor substrate, the processing liquid mist is likely to adhere to the surface of the semiconductor substrate. In recent years, the wiring dimension on a semiconductor substrate has been miniaturized to a sub-micron size, and when a micron-sized processing liquid mist adheres to the surface of a semiconductor substrate, it tends to cause a wiring defect or a yield reduction of the semiconductor device.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a substrate processing apparatus in which adhesion of processing liquid mist on the substrate is suppressed.

  According to the present invention, the substrate holding means for holding and rotating the substrate, the processing liquid supply means for supplying the processing liquid onto the substrate, and the container provided so as to surround the side and the lower side of the substrate, Provided is a substrate processing apparatus in which an inner wall of a container is processed into a shape that suppresses an upward air flow generated by the rotation of the substrate.

  According to this configuration, the rising air flow generated by the rotation of the substrate is suppressed by the shape of the inner wall of the container, so that it is possible to suppress the processing liquid mist from rising above the substrate surface position. For this reason, it can suppress that process liquid mist adheres to a board | substrate.

  Further, according to the present invention, the substrate holding means for holding and rotating the substrate, the processing liquid supply means for supplying the processing liquid onto the substrate, and the side and lower sides of the substrate are provided. There is provided a substrate processing apparatus including a container and a plurality of stages of grooves provided in parallel on the inner wall of the container.

  According to this structure, the rising airflow which generate | occur | produces by rotation of a board | substrate is suppressed by the multistage groove part provided in parallel with the inner wall of a container. For this reason, since it can suppress that process liquid mist soars upwards rather than a substrate surface position, it can suppress that process liquid mist adheres to a board | substrate.

  According to the present invention, since the configuration for suppressing the rising airflow is provided, it is possible to suppress the treatment liquid mist from adhering to the substrate.

  In the present invention, the above-mentioned plurality of groove portions may be groove portions provided in an oblique direction with respect to the substrate on the inner wall of the container. According to this configuration, the upward air flow generated by the rotation of the substrate is efficiently suppressed. The angle at which the groove is inclined with respect to the substrate can be set as appropriate according to the shape of the container, the size of the substrate, the rotation direction of the substrate, the rotation speed of the substrate, and the like.

  In the present invention, the above-mentioned plurality of groove portions may be groove portions provided spirally on the inner wall of the container. According to this configuration, a plurality of groove portions are formed on the inner wall of the container, so that an upward air flow generated by the rotation of the substrate is suppressed. In addition, the spiral groove part may be comprised from one spiral groove part, and the several spiral groove part may be parallel.

  The groove may have a downward inclination with respect to the traveling direction of the peripheral edge of the substrate.

  According to this configuration, when the outward airflow generated by the rotation of the substrate is converted into the rising airflow along the inner wall, the plurality of groove portions inclined downward with respect to the traveling direction of the peripheral edge of the substrate are traversed in the vertical direction. It will be. As a result, the ascending force of the updraft is attenuated as the resistance force on the updraft increases.

  The substrate processing apparatus may further include a drainage unit that discharges the processing liquid in the container, and the groove may be provided up to the vicinity of the waste liquid unit.

  According to this configuration, the processing liquid that accumulates in the groove is discharged from the container through the waste liquid means in the vicinity of the lower end of the groove. For this reason, the amount of the processing liquid remaining in the container is reduced, and it is possible to suppress the processing liquid mist from adhering to the substrate.

  Further, the above-mentioned plurality of groove portions may be linear concave portions provided on the inner wall of the container. Or the area | region between the linear convex part provided in the inner wall of a container and a convex part may be sufficient. Each groove may have a certain width.

  Moreover, arbitrary shapes can be employ | adopted for the cross-sectional shape of a groove part, a square shape may be sufficient, a semicircle shape may be sufficient, and a wedge shape may be sufficient. Such a groove can be formed by mechanically scraping the inner wall of the container. Moreover, the number of steps of the groove provided on the inner wall of the container is not particularly limited. The plurality of groove portions may be groove portions provided as a plurality of independent groove portions on the inner wall of the container. In addition, the groove portion does not need to be continuous and may be provided intermittently.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a cross-sectional view schematically showing a part of a substrate processing apparatus according to an embodiment. FIG. 2 is a top view schematically showing a part of the substrate processing apparatus according to the embodiment. FIG. 1 is a cross-sectional view taken along line B-B ′ of the top view of FIG. 2. In the substrate processing apparatus according to this embodiment, as shown in FIGS. 1 and 2, a spiral cut structure 4 is added to the inner wall of the processing cup 1.

  That is, the substrate processing apparatus according to this embodiment includes a spin chuck 3 (substrate holding means) that holds and rotates the wafer 2 (substrate), and a chemical solution discharge nozzle 5 (processing solution supply) that supplies the processing liquid onto the wafer 2. Means) and a processing cup 1 (container) provided so as to surround the side and lower side of the wafer 2. The wafer 2 is held substantially horizontally by the spin chuck 3 using a vacuum suction method.

  The inner wall of the processing cup 1 is provided with a spiral cutting structure 4 (spiral groove). Alternatively, the inner wall of the processing cup 1 may be provided with a plurality of cut structures 4 (a plurality of groove portions) parallel to the wafer 2 in an oblique direction. Alternatively, a plurality of cut structures 4 may be provided in the horizontal direction with respect to the wafer 2. Such a cut structure 4 provided on the inner wall of the processing cup 1 functions as a means for suppressing the upward air flow generated by the rotation of the wafer 2.

  As a result, when the outward airflow 9 from the rotation center of the spin chuck 3 near the upper surface of the wafer 2 and the lower surface of the wafer 2 toward the inner wall of the processing cup 1 generated along with the rotation of the wafer 2 is converted into an ascending airflow 10 along the inner wall. Then, the cut structure 4 inclined downward along the cylindrical inner wall shape is traversed in the vertical direction a plurality of times. For this reason, since the ascending force of the ascending airflow 10 is attenuated and can be prevented from rising above the wafer 2 surface position, the processing liquid mist adheres to the waiting wafer 2 in the processing cup 1. Can be suppressed.

  Further, the treatment liquid mist contained in the airflow is accumulated in the gaps of the spiral cut structure 4 and flows downward along the inclination. Therefore, this spiral cut structure 4 also has an effect of reducing the content of the processing liquid mist in the airflow.

  As a result, when the wafer 2 is vacuum-adsorbed in the processing cup 1 and chemical processing is performed while rotating, the processing liquid mist generated during the chemical processing adheres to the wafer 2 waiting in the processing cup 1 after the processing is completed. Is suppressed. In addition, adhesion of the processing liquid mist to another wafer 2 located outside the processing cup 1 can be suppressed. For this reason, if the wafer 2 is processed with a chemical solution using this substrate processing apparatus, wiring defects on the wafer 2 are reduced, so that the yield of semiconductor devices using the wafer 2 is improved.

  Hereinafter, the configuration of the semiconductor device according to the present embodiment will be described in more detail.

  As shown in FIGS. 1 and 2, the inner wall of the processing cup 1 has a spiral cut structure 4 having a downward slope from the upper end. The cutting process proceeds with a downward inclination from the upper end of the processing cup 1 over the entire vertical portion of the inner wall of the processing cup 1, and with respect to the traveling direction of the peripheral edge of the wafer 2 (the rotation direction of the wafer 2). Is applied in a downward spiral.

  FIG. 3 is an enlarged view schematically showing a spiral cut structure of the inner wall of the processing cup of the substrate processing apparatus according to the embodiment. 3 is an enlarged perspective view of a portion A in the top view of FIG.

  In a substrate processing apparatus in which a spiral cutting structure 4 is provided on the cylindrical inner wall of the processing cup 1, the wafer 2 vacuum-sucked by the spin chuck 3 rotates after the chemical solution is discharged from the chemical solution discharge nozzle 5. The surface is treated with a chemical solution. Simultaneously with the rotation, centrifugal force is generated in the air in the vicinity of the upper surface of the wafer 2 and in the vicinity of the lower surface of the wafer 2, and an outward airflow 9 is generated from the rotation center of the spin chuck 3 toward the inner wall of the processing cup 1.

  When the outward airflow 9 is converted into an ascending airflow 10 along the inner wall, the notch structure 4 having a downward inclination is traversed in the vertical direction so as to follow the cylindrical inner wall shape (relative to the rotation direction of the wafer 2). It will be. As a result, the ascending force of the updraft 10 is attenuated as the resistance force on the updraft 10 increases. Since the cut structure 4 is provided in a spiral shape, the cylindrical inner wall has a plurality of cut structures 4 from the bottom wall to the top surface. Therefore, the updraft 10 repeats the crossing of the unevenness a plurality of times, and the ascending force of the updraft 10 is greatly attenuated.

  Further, an exhaust port 7 is provided in the bottom wall of the processing cup 1, and an airflow that flows downward while constantly taking in a clean room atmosphere from the upper opening of the processing cup 1 by a negative pressure source such as a factory utility or a pump is always present. Exists. Therefore, a downward airflow also exists in the spiral cut structure 4 provided on the inner wall of the processing cup 1. Therefore, the ascending air flow 10 including the processing liquid mist along the inner wall of the processing cup 1 generated by the rotation of the wafer 2 faces downward along with the attenuation of the ascending force by repeating the crossing of the spiral cut structure 4 a plurality of times. Merge with airflow. As a result, this air flow is discharged from the exhaust port 7 without rising above the wafer 2 surface position.

  When the rotation direction of the wafer 2 is clockwise, the incision structure 4 (helical sawtooth) is formed in the lower right direction (that is, applied in a downward spiral shape with respect to the rotation direction of the wafer 2). )

  Therefore, as shown in FIG. 1, the processing liquid mist contained in the outward airflow 9 generated by the rotation of the wafer 2 is absorbed by the liquid reservoir 8 existing in the gap of the spiral cut structure 4. Then, the processing liquid mist absorbed in the liquid reservoir 8 flows downward along the inclination of the liquid reservoir 8 and is discharged from the waste liquid port 6. By doing so, the content of the treatment liquid mist in the airflow is reduced.

  Further, it is effective from the viewpoint of waste liquid efficiency to provide the lower end of the liquid reservoir 8 in the vicinity of the waste liquid port 6. In other words, the processing liquid that has descended through the liquid reservoir 8 can be guided to the waste liquid port 6. By doing so, the processing liquid that has reached the lower end of the liquid reservoir 8 easily flows into the waste liquid port 6 and the amount of the processing liquid remaining in the processing cup 1 is reduced. Can be prevented from jumping up and adhering to the wafer 2. Further, as shown in FIG. 1, the liquid reservoir 8 is more likely to absorb the processing liquid mist if it is formed downward as it goes deeper.

  As described above, the airflow including the processing liquid mist generated when the wafer 2 is subjected to the chemical processing in the processing cup 1 is switched downward without flowing up above the surface position of the wafer 2. In addition to preventing scattering of the processing liquid mist to the outside of the processing unit, it is possible to prevent the processing liquid mist from adhering to the wafer 2 waiting in the processing cup 1 after the chemical processing is completed.

  Further, since there is no protrusion such as a rectifying plate protruding to the position corresponding to the inner side of the edge of the wafer 2 at the upper part of the processing cup 1, there is a risk that the processing liquid accumulated in the protrusion or the like falls. There are few. Further, since the processing liquid mist contained in the airflow is accumulated in the gaps of the spiral cut structure 4 and flows downward along the inclination of the cut structure 4, the content of the processing liquid mist in the airflow decreases.

  Hereinafter, the operation and effect of the semiconductor device according to the present embodiment will be described in comparison with the prior art.

  In the present embodiment, in a substrate processing apparatus that performs vacuum processing while the wafer 2 is vacuum-adsorbed by the spin chuck 3 in the processing cup 1 and is rotated, processing liquid mist generated during processing is generated in the processing cup 1 after the processing is completed. There is no sticking to the waiting wafer. Moreover, since the adhesion of the processing liquid mist to another wafer 2 located outside the processing cup 1 can be suppressed, wiring defects formed on the wafer 2 can be reduced and the yield of semiconductor devices using the wafer 2 can be improved. The effect to do.

  On the other hand, in Patent Document 1, as shown in FIG. 4, the processing liquid mist that has risen to the position above the wafer W position as the rising airflow 91 is converted into an inward airflow 92 and discharged below the processing cup 30. Therefore, the airflow containing the processing liquid mist easily collides with the wafer surface.

  In addition, since the inner edge portion 42a of the rectifying plate 42 at the upper edge of the splash guard 40 protrudes to a position corresponding to the inner side of the edge portion of the wafer W held by the spin chuck 20, the time lapses. The processing liquid collected at the tip of the inner edge portion 42a tends to fall on the wafer W.

  Therefore, the remaining processing liquid mist may adhere to the wafer W that is waiting until the chemical processing is completed in the processing cup 30 and unloaded from the processing cup 30. In recent years, the wiring dimension on the wafer W has been miniaturized to a sub-micron size, and if a micron-sized mist adheres to the surface of the wafer W, it becomes a wiring defect and tends to cause a decrease in yield.

  Further, in both Patent Document 2 and Patent Document 3, since the processing liquid mist generated by the rotation after dropping the processing droplet is likely to rise to a position above the surface of the semiconductor substrate held by the spin chuck from the structure, the processing liquid mist Is likely to fall on the surface of the semiconductor substrate.

  In particular, the liquid processing apparatus of Patent Document 2 may cause the processing liquid mist to bounce off the fins. In addition, since the multi-stage shielding plate is present in the processing cup in the thin film coating apparatus of Patent Document 3, the outward airflow generated by the rotation after dropping the processing droplet becomes turbulent, and processing is performed on the back surface of the semiconductor substrate. Liquid mist may adhere.

  For this reason, also in patent document 2 and patent document 3, if a micron-sized mist adheres to the semiconductor substrate surface, it will become a wiring defect and it will be easy to cause a yield fall.

  On the other hand, the substrate processing apparatus according to this embodiment includes a processing cup 1. The substrate processing apparatus also includes a chemical solution discharge nozzle 5 for dropping a chemical solution onto a substrate (hereinafter referred to as a wafer 2 as appropriate) and a spin chuck 3 for rotating the wafer 2 inside the processing cup 1. . Then, when the rotation direction of the wafer 2 is clockwise, the notch structure 4 (helical sawtooth) is formed in the lower right direction (that is, a downward spiral with respect to the rotation direction of the wafer 2). Is given to the shape).

  In this substrate processing apparatus, a wafer 2 is vacuum-sucked by a spin chuck 3 in a processing cup 1 and chemical processing is performed while rotating. For this reason, since the outward airflow 9 generated by the rotation after dropping the processing droplet is directed obliquely downward along the groove of the notch structure 4, the processing liquid mist is located at a position above the surface of the wafer 2. It is hard to rise. In addition, due to the action of the downflow from the upper part of the processing cup 1, the air flow 10 rising from the bottom wall of the processing cup 1 gets over the spiral cut structure 4 in several stages, and the surface position of the wafer 2 is reached. Almost disappears before reaching.

  Thus, since this substrate processing apparatus is provided with a helical saw tooth (cut structure 4) on the outwardly downward side of the processing cup 1, this substrate processing apparatus is generated when the wafer 2 is processed with a chemical solution. The processing liquid mist is prevented from adhering to the wafer 2 waiting in the processing cup 1 after the processing is completed. Further, the adhesion of the processing liquid mist to another wafer 2 located outside the processing cup 1 is similarly suppressed.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  For example, in the above-described embodiment, a raw material liquid for a resist film provided on the wafer 2 can be used as the processing liquid, but is not particularly limited thereto. In addition, any liquid such as a cleaning liquid or an etching liquid can be used.

  In the above-described embodiment, the inner wall of the processing cup 1 has a plurality of cut structures 4 provided in parallel to the wafer 2 in an oblique direction. However, the present invention is not limited to this. In addition, a plurality of cut structures 4 may be provided in the horizontal direction with respect to the wafer 2. Even with such a structure, the rising airflow 10 generated by the rotation of the wafer 2 can be suppressed.

It is sectional drawing which showed typically a part of substrate processing apparatus concerning embodiment. It is the top view which showed typically a part of substrate processing apparatus concerning an embodiment. It is the enlarged view which showed typically the spiral cut structure of the process cup inner wall of the substrate processing apparatus which concerns on embodiment. It is sectional drawing which showed a part of conventional substrate processing apparatus typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Processing cup 2 Wafer 3 Spin chuck 4 Cutting structure 5 Chemical solution discharge nozzle 6 Waste liquid port 7 Exhaust port 8 Liquid pool 9 Outward air flow 10 Ascending air flow 20 Spin chuck 30 Processing cup 31 Bottom wall 32 Side wall 33 Exhaust port 37 Negative pressure source 40 Splash guard 41 Main body 42 Current plate 42a Inner edge 43 Opening 50 Processing chamber 90 Downflow 91 Upflow 92 Inward airflow W Wafer

Claims (6)

A substrate holding means for holding and rotating the substrate;
Treatment liquid supply means for supplying a treatment liquid onto the substrate;
A container provided so as to surround a side and a lower side of the substrate;
With
The substrate processing apparatus, wherein an inner wall of the container is processed into a shape that suppresses an upward air flow generated by the rotation of the substrate. A substrate holding means for holding and rotating the substrate;
Treatment liquid supply means for supplying a treatment liquid onto the substrate;
A container provided so as to surround a side and a lower side of the substrate;
A plurality of grooves provided in parallel on the inner wall of the container;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 2,
The substrate processing apparatus, wherein the groove is provided on the inner wall of the container in an oblique direction with respect to the substrate. In the substrate processing apparatus of Claim 2 or 3,
The substrate processing apparatus, wherein the groove is spirally provided on the inner wall of the container. The substrate processing apparatus according to any one of claims 2 to 4,
The substrate processing apparatus, wherein the groove portion has a downward inclination with respect to a traveling direction of a peripheral portion of the substrate. The substrate processing apparatus according to any one of claims 2 to 5,
A drainage means for discharging the processing liquid in the container;
The substrate processing apparatus, wherein the groove is provided to the vicinity of the waste liquid means.

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