JP2010205876A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing apparatus and a substrate processing method, capable of selectively etch-removing only the upper layer formed on a surface edge part of a substrate. <P>SOLUTION: While a chemical is supplied to a hardly soluble layer UL formed at the surface edge part TR of the substrate W to remove the hardly soluble layer UL by etching, a rinse liquid is supplied to the substrate-end surface side of the hardly soluble layer UL to form a cover rinse part CL, and a base layer DL exposed by etching-removing of the hardly soluble layer UL is covered with the rinse liquid. For this reason, the chemical flowing to the base layer DL is diluted, and the base layer DL exposed by flushing away is prevented from being etched by the chemical. In this way, since the etching process is performed in a condition where the cover rinse part CL is provided to the substrate-end surface side of the hardly soluble layer UL and the exposed base layer DL is protected, only the hardly soluble layer UL formed at the surface edge part TR of the substrate W is selectively etch-removed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for etching and removing a thin film adhering to a peripheral edge portion of a surface of a substrate. The substrates include semiconductor wafers, photomask glass substrates, liquid crystal display glass substrates, plasma display glass substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, and magneto-optical disk substrates. Etc. (hereinafter simply referred to as “substrate”).

  In order to remove the thin film adhering to the peripheral edge of the surface of the substrate, for example, an apparatus described in Patent Document 1 has been proposed. In this apparatus, the substrate is arranged on the spin chuck in a horizontal posture with the surface facing upward, and the blocking member is arranged facing the substrate surface at a position above the substrate. And a nozzle is inserted in the nozzle insertion hole provided in the peripheral part of this interruption | blocking member, a chemical | medical solution is supplied toward the surface peripheral part of the rotating board | substrate, and a thin film is etched away from the surface peripheral part. Thus, Patent Document 1 describes an apparatus that performs a bevel etching process on a substrate.

JP 2008-47629 A (FIGS. 1 and 7)

  By the way, in recent years, a hardly soluble layer such as a TaN (tantalum nitride) layer or a W (tungsten) layer has become one of the target thin films for the bevel etching process. Of these, the TaN layer is a thin film formed to form a barrier film on the substrate, and the W layer is a thin film formed as an electrode layer. In order to remove such a hardly soluble layer by etching, it is necessary to use a high concentration chemical solution, but the etching rate is low. On the other hand, the etching rate of the base layer such as a Th-Ox (thermal oxidation) layer provided on the substrate surface as the base of the hardly soluble layer or the substrate base is higher than that of the hardly soluble layer. For example, the etching selection of the Th-Ox layer The ratio is 3.4 with respect to the etching selectivity of the W layer. For this reason, the following problems may occur. The “etching selection ratio” means the ratio of the degree of etching removal with a chemical solution.

  In order to etch away the poorly soluble layer formed on the peripheral edge of the surface of the substrate, it is necessary to use a high-concentration chemical solution such as hydrofluoric acid as described above, but the etching reaction is secondary reaction, The etching process is not started when the chemical solution comes into contact with the poorly soluble layer, and the etching process is started after a while after the liquid contact with the substrate surface. Therefore, it has been confirmed that etching removal of the hardly soluble layer proceeds from the end surface side of the substrate toward the center of the surface of the substrate. That is, after the start of the supply of the chemical solution, the substrate end face side of the hardly soluble layer is first removed by etching to expose the substrate base and the underlying layer, and further the etched removal portion of the hardly soluble layer spreads to the liquid contact portion. Therefore, during the etching removal of the hardly soluble layer from the peripheral edge portion of the substrate surface, the non-processed portion (substrate that should not be etched by contact with the chemical solution on the substrate base or underlayer on the substrate end surface side of the hardly soluble layer) In some cases, the exposed surface portion of the substrate or the underlayer is etched.

  In addition, in the case where a hardly soluble layer is formed on the peripheral edge of the surface of the substrate so that the substrate base or the underlying layer is exposed in the vicinity of the substrate end surface or in the vicinity of the substrate end surface (see FIG. 8A described later), the hardly soluble layer The etching removal of the substrate base and the underlayer is started earlier than the etching removal. Moreover, the etching progress rate is several times faster for the substrate substrate and the underlayer than for the hardly soluble layer. As a result, etching removal of the substrate substrate and the underlying layer may proceed further to the center side of the substrate than the wetted portion where the chemical solution is contacted in order to etch away the hardly soluble layer. When this unexpected etching process occurs, the non-removable part of the poorly soluble layer that should not be removed by etching and left on the substrate surface, that is, the poorly soluble layer on the center side of the substrate with respect to the wetted part, so-called overhang state End up. Then, the slightly soluble layer that floats as described above may peel off during the subsequent manufacturing process, and if the peeled material adheres again to the substrate surface, serious defects may occur in the circuits formed on the substrate. There is sex.

  Furthermore, as described above, when the end surface of the substrate base or the vicinity of the end surface is melted, the substrate may be poorly transported or damaged, which is a significant loss factor in the production line.

  This invention is made in view of the said subject, and it aims at providing the substrate processing apparatus and substrate processing method which can selectively etch away only the upper layer formed in the surface peripheral part of the board | substrate. .

  A substrate processing apparatus according to the present invention is a substrate processing apparatus that removes an upper layer formed on a peripheral surface of a rotating substrate. In order to achieve the above object, the substrate processing apparatus is configured as follows. That is, the substrate processing apparatus according to the present invention supplies a chemical solution supplying means for supplying a chemical solution to the upper layer and etching and removing the upper layer, and supplying a rinsing solution to the substrate end surface side of the liquid contact portion where the chemical solution contacts the upper layer. Cover rinsing means for covering a non-processed portion that is not covered with the upper layer in the peripheral portion of the surface with a rinsing liquid is provided.

  In addition, in order to achieve the above object, the substrate processing method according to the present invention supplies a chemical solution to the upper layer formed on the peripheral edge of the surface of the rotating substrate, and etches and removes the upper layer. And a cover rinsing step in which the chemical liquid contacts the upper layer, the rinse liquid is supplied to the substrate end surface side of the liquid contact portion, and the non-processed portion that is not covered with the upper layer of the surface peripheral portion is covered with the rinse liquid. It is characterized by that.

  In the invention configured as described above (substrate processing apparatus and substrate processing method), when the chemical solution is supplied to the upper layer formed on the peripheral edge portion of the substrate and the upper layer is removed by etching, the upper layer is rinsed to the substrate end surface side. The non-processed part which is supplied with the liquid and is not covered with the upper layer is covered with the rinse liquid. Therefore, even if the chemical solution reaches the non-processed portion, it is possible to prevent the non-processed portion from being etched by the chemical solution by protecting the rinse solution.

  According to the present invention, the rinsing liquid is supplied to the substrate end surface side of the liquid contact portion, and the cover rinsing portion is formed by covering the non-treated portion that is not covered with the upper layer of the surface peripheral portion with the rinsing liquid. The non-processed part is protected by the cover rinse part, and only the upper layer formed on the peripheral edge of the surface of the substrate can be selectively removed without etching the non-processed part.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the substrate processing apparatus concerning this invention. It is a block diagram which shows the main control structures of the substrate processing apparatus of FIG. It is a bottom view of a blocking member. It is a figure which shows the structure of the nozzle insertion hole provided in the chemical | medical solution discharge nozzle and the interruption | blocking member. It is a schematic diagram which shows operation | movement of the substrate processing apparatus of FIG. It is a fragmentary sectional view of FIG. It is a schematic diagram which shows operation | movement of 2nd Embodiment of the substrate processing apparatus concerning this invention. It is a fragmentary sectional view of FIG.

  FIG. 1 is a diagram showing a first embodiment of a substrate processing apparatus according to the present invention. FIG. 2 is a block diagram showing a main control configuration of the substrate processing apparatus of FIG. This substrate processing apparatus is an apparatus that etches and removes a hardly soluble layer such as a TaN layer or a W layer present on the peripheral portion TR of the surface Wf of a substantially circular substrate W such as a semiconductor wafer. In this embodiment, as will be described later, a substrate W in which a base layer such as a Th-Ox (thermal oxidation) layer is formed on the substrate surface Wf and a poorly soluble layer such as a W layer is further formed on the base layer. In the surface peripheral portion TR of the substrate W, the hardly soluble layer is positioned at the top and corresponds to the “upper layer” of the present invention.

  The substrate processing apparatus includes a spin chuck 1 that rotates while holding the substrate W in a substantially horizontal position with the substrate surface Wf facing upward, and the center of the lower surface (back surface Wb) of the substrate W held by the spin chuck 1. The chemical liquid comes into contact with the lower surface processing nozzle 2 for supplying the rinsing liquid toward the portion, the chemical liquid discharge nozzle 3 for supplying the chemical liquid to the surface peripheral portion TR of the substrate W held by the spin chuck 1 from the substrate surface Wf side. A rinsing liquid discharge nozzle 4 for supplying a rinsing liquid such as DIW (deionized water) to the substrate end face side of the liquid contact portion (reference numeral Pe in FIG. 6), and the surface of the substrate W held by the spin chuck 1 And a blocking member 5 disposed to face Wf.

  The spin chuck 1 has a hollow rotating support shaft 11 connected to a rotating shaft of a chuck rotating mechanism 13 including a motor, and can be rotated around a rotation center A 0 by driving the chuck rotating mechanism 13. A spin base 15 is integrally connected to the upper end portion of the rotating spindle 11 by a fastening part such as a screw. Therefore, the spin base 15 rotates around the rotation center A0 by driving the chuck rotation mechanism 13 in accordance with an operation command from the control unit 8 that controls the entire apparatus. On the upper surface 151 of the spin base 15, support pins 152 are provided protruding upward so as to contact the lower surface of the substrate W and support the substrate W from below. The number of support pins 152 is not particularly limited, but for example, by providing three or more equiangular intervals, the wafer W can be supported horizontally and stably.

  A rinsing liquid supply pipe 21 is inserted through the hollow rotating spindle 11, and the lower surface processing nozzle 2 is coupled to the upper end thereof. The rinse liquid supply pipe 21 is connected to the rinse liquid supply unit 17, and DIW is supplied as the rinse liquid. Further, a gap between the inner wall surface of the rotating spindle 11 and the outer wall surface of the rinse liquid supply pipe 21 forms an annular gas supply path 23. The gas supply path 23 is connected to the gas supply unit 18, and a space in which nitrogen gas is sandwiched between the substrate back surface Wb and the upper surface 151 of the spin base 15 facing the substrate back surface Wb via the gas supply path 23. Supplied to SP1. In this embodiment, nitrogen gas is supplied from the gas supply unit 18, but air or other inert gas may be discharged.

  Above the spin chuck 1, a disc-shaped blocking member 5 that faces the substrate W supported by the support pins 152 is disposed horizontally. The blocking member 5 is attached to a lower end portion of a rotation support shaft 51 arranged coaxially with the rotation support shaft 11 of the spin chuck 1 so as to be integrally rotatable. A blocking member rotating mechanism 53 is connected to the rotation support shaft 51, and the blocking member 5 is driven around the rotation center A0 by driving the motor of the blocking member rotating mechanism 53 in accordance with an operation command from the control unit 8. Rotate. The control unit 8 controls the blocking member rotating mechanism 53 to synchronize with the chuck rotating mechanism 13, thereby rotating the blocking member 5 with the same rotation direction and the same rotation speed as the spin chuck 1.

  The blocking member 5 is connected to the blocking member elevating mechanism 55, and the substrate W holding the blocking member 5 on the spin base 15 by operating an elevating drive actuator (for example, an air cylinder) of the blocking member elevating mechanism 55. It is possible to make them face each other close to each other or to separate them. Specifically, the control unit 8 drives the blocking member raising / lowering mechanism 55 so that when the substrate W is loaded into or unloaded from the substrate processing apparatus, the control unit 8 is blocked at a spaced position sufficiently away from the spin chuck 1. The member 5 is raised. On the other hand, when a predetermined process such as an etching process is performed on the substrate W, the blocking member 5 is lowered to a facing position set very close to the surface Wf of the substrate W held by the spin chuck 1. . As a result, the lower surface 501 (substrate facing surface) of the blocking member 5 and the substrate surface Wf are arranged to face each other in a close proximity.

  The central opening of the blocking member 5 and the hollow portion of the rotation support shaft 51 form a gas supply path 57. The gas supply path 57 is connected to the gas supply unit 18, and nitrogen gas is introduced into a space SP <b> 2 sandwiched between the substrate surface Wf and the lower surface 501 of the blocking member 5 through a gas distribution space 503 and a gas discharge port 502 described later. Supply is possible.

  FIG. 3 is a bottom view of the blocking member. The planar size of the lower surface 501 of the blocking member 5 is formed to be equal to or larger than the diameter of the substrate W. For this reason, when the blocking member 5 is disposed at the facing position, the atmosphere on the substrate surface Wf can be blocked from the external atmosphere by covering the entire substrate surface. In addition, nozzle insertion holes 5A and 5B having a substantially cylindrical inner space penetrating the blocking member 5 in the vertical direction (vertical axis direction) are formed in the peripheral portion of the blocking member 5. It can be inserted individually. The nozzle insertion hole 5A and the nozzle insertion hole 5B are formed in the same shape at symmetrical positions with respect to the rotation center A0. On the other hand, the chemical liquid discharge nozzle 3 and the rinse liquid discharge nozzle 4 have the same nozzle outer diameter. For this reason, both the nozzles 3 and 4 can be inserted into any of the nozzle insertion holes 5A and 5B.

  A plurality of gas discharge ports 502 are formed on the lower surface 501 of the blocking member 5. The plurality of gas discharge ports 502 are arranged on the circumference centered on the rotation center A0 at a position facing the central portion of the surface of the substrate W held by the spin chuck 1, that is, the non-process region radially inward of the surface peripheral portion TR. It is formed at equiangular intervals along. These gas discharge ports 502 communicate with a gas circulation space 503 (FIG. 1) formed inside the blocking member 5, and when nitrogen gas is supplied to the gas circulation space 503 through the gas supply path 57, Nitrogen gas is supplied to the space SP2 through the plurality of gas discharge ports 502.

  When nitrogen gas is supplied from the plurality of gas discharge ports 502 to the space SP2 with the blocking member 5 positioned at the opposing position, the internal pressure of the space SP2 is increased and the substrate W is brought into contact with the back surface Wb. Press against the support pin 152. When the spin base 15 rotates in accordance with the operation command of the control unit 8 in this state, the substrate W rotates with the spin base 15 while being supported by the support pins 152 by the frictional force generated between the substrate back surface Wb and the support pins 152. To do. Note that the nitrogen gas supplied to the space SP2 flows outward in the radial direction of the substrate W.

  Returning to FIG. 1, the description will be continued. The chemical solution discharge nozzle 3 is connected to the chemical solution supply unit 16, and supplies the chemical solution from the chemical solution supply unit 16 to the chemical solution discharge nozzle 3 in response to an operation command from the control unit 8. As the chemical solution, a chemical solution suitable for etching a poorly soluble layer such as a TaN layer or a W layer, such as hydrofluoric acid, is used.

  The chemical liquid discharge nozzle 3 is attached to one end of a nozzle arm 31 extending in the horizontal direction. The other end of the nozzle arm 31 is connected to the first nozzle moving mechanism 33. The first nozzle moving mechanism 33 can swing the chemical liquid discharge nozzle 3 in the horizontal direction around a predetermined rotation axis and raise and lower the chemical liquid discharge nozzle 3. For this reason, the first nozzle moving mechanism 33 is driven in accordance with an operation command from the control unit 8, whereby the chemical liquid discharge nozzle 3 is inserted into the nozzle insertion hole 5 </ b> A of the blocking member 5 and the chemical liquid is supplied to the surface peripheral portion TR. It can be moved to a processing position (chemical solution supply position) P31 that can be supplied and a standby position P32 that is away from the substrate W. Further, when the chemical solution is pumped from the chemical solution supply unit 16 in a state where the chemical solution discharge nozzle 3 is inserted into the nozzle insertion hole 5A of the blocking member 5, the chemical solution is supplied from the chemical solution discharge nozzle 3 to the surface peripheral portion TR and is hardly soluble. Etching is removed. A region where the chemical liquid contacts the poorly soluble layer in the surface peripheral portion TR is referred to as “liquid contact portion Pe”.

  The rinse liquid discharge nozzle 4 is connected to the rinse liquid supply unit 17 and supplies DIW from the rinse liquid supply unit 17 to the rinse liquid discharge nozzle 4 in accordance with an operation command from the control unit 8. The rinsing liquid discharge nozzle 4 can supply the rinsing liquid to the substrate end face side from the liquid contact part Pe of the chemical liquid to the surface peripheral edge TR. Further, a second nozzle moving mechanism 43 is provided to drive the rinse liquid discharge nozzle 4. The second nozzle moving mechanism 43 has the same configuration as the first nozzle moving mechanism 33. In other words, the second nozzle moving mechanism 43 can swing the rinsing liquid discharge nozzle 4 attached to the tip of the nozzle arm 41 in the horizontal direction around a predetermined rotation axis, and can move the rinsing liquid discharge nozzle 4 up and down. . For this reason, the second nozzle moving mechanism 43 is driven in accordance with an operation command from the control unit 8, whereby the rinse liquid discharge nozzle 4 is inserted into the nozzle insertion hole 5 </ b> B of the blocking member 5 to rinse the surface peripheral portion TR. It can be moved to a processing position (rinsing liquid supply position) P41 where the liquid can be supplied and a standby position P42 which is away from the substrate W.

  Here, the nozzle insertion hole 5A and the nozzle insertion hole 5B have the same shape as the blocking member 5 and are formed symmetrically with respect to the rotation center A0, and in a direction extending from the rotation center A0 to the processing position P31 in plan view. The angle formed by the direction extending from the rotation center A0 to the processing position P41 is 180 °. Both nozzles 3 and 4 are configured identically except that the types of liquids to be discharged are different. Both nozzle insertion holes 5A and 5B have the same shape as the blocking member 5 and are formed symmetrically with respect to the rotation center A0. Therefore, only the configuration of the chemical solution discharge nozzle 3 and the nozzle insertion hole 5A will be described with reference to FIG.

  FIG. 4 is a diagram showing the configuration of the nozzle insertion hole provided in the chemical liquid discharge nozzle and the blocking member. The chemical liquid discharge nozzle 3 is formed in a substantially cylindrical shape in accordance with the shape of the nozzle insertion hole 5A provided in the blocking member 5, and is inserted into the nozzle insertion hole 5A so that the distal end side of the chemical liquid discharge nozzle 3 is the surface peripheral portion TR. It is arrange | positioned facing. A liquid supply path 301 is formed inside the chemical liquid discharge nozzle 3, and a tip end (lower end) of the liquid supply path 301 constitutes a discharge port 301 a of the chemical liquid discharge nozzle 3. The outer diameter of the chemical solution discharge nozzle 3 is, for example, about φ5 to 6 mm so as not to increase the diameter of the nozzle insertion hole 5A more than necessary. The chemical liquid discharge nozzle 3 is configured such that the cross-sectional area of the nozzle body formed in a substantially cylindrical shape is different between the nozzle front end side and the rear end side. Specifically, the cross-sectional area of the body 302 on the nozzle front end side is configured to be smaller than the cross-sectional area of the body 303 on the nozzle rear end side, and the body 302 on the nozzle front end side and the nozzle rear end side on the nozzle rear end side are configured. A step surface 304 is formed between the body portion 303 and the body portion 303. That is, the outer peripheral surface (side surface) of the body 302 on the nozzle front end side and the outer peripheral surface (side surface) of the body 303 on the rear end side of the nozzle are connected via the step surface 304. The step surface 304 is formed so as to surround the body portion 302 on the nozzle tip side and substantially parallel to the substrate surface Wf held by the spin chuck 1.

  An annular contact surface 504 that can contact the step surface 304 of the chemical liquid discharge nozzle 3 is formed on the inner wall of the nozzle insertion hole 5A. When the chemical liquid discharge nozzle 3 is inserted into the nozzle insertion hole 5A, the step surface 304 and the contact surface 504 come into contact with each other, whereby the chemical liquid discharge nozzle 3 is positioned at the processing position P31. In a state where the chemical liquid discharge nozzle 3 is positioned at the processing position P31, the tip surface around the discharge port 301a of the chemical liquid discharge nozzle 3 is flush with the opposing surface 501 of the blocking member 5. The contact surface 504 is formed substantially parallel to the facing surface 501 of the blocking member 5, that is, substantially parallel to the substrate surface Wf, and is in surface contact with the step surface 304 of the chemical liquid discharge nozzle 3. For this reason, when the chemical solution discharge nozzle 3 is positioned at the processing position P31, the chemical solution discharge nozzle 3 comes into contact with the blocking member 5 and is fixed in position, so that the chemical solution discharge nozzle 3 can be positioned stably.

  The discharge port 301a of the chemical solution discharge nozzle 3 is opened toward the outside in the radial direction of the substrate W, and the chemical solution is directed from the discharge port 301a toward the substrate end surface side from the upper center of rotation of the substrate W (arrows in FIGS. 6 and 8). Direction) and can be supplied to the surface peripheral portion TR. The liquid supply path 301 is connected to the chemical liquid supply unit 16 at the nozzle rear end. For this reason, when the chemical liquid is pumped from the chemical liquid supply unit 16 to the liquid supply path 301, the chemical liquid is discharged from the chemical liquid discharge nozzle 3 toward the outside in the radial direction of the substrate W. Thereby, the chemical solution supplied to the surface peripheral portion TR flows toward the outside in the radial direction of the substrate W and is discharged out of the substrate. Accordingly, the chemical solution is not supplied to the non-process region radially inward from the supply position of the chemical solution, and the thin film is etched away with a constant width (peripheral etching width) from the end surface of the substrate W to the inside. Further, the discharge port of the rinse liquid discharge nozzle 4 is also opened outward in the radial direction of the substrate W in the same manner as the chemical liquid discharge nozzle 3, and DIW can be discharged from the discharge port to the surface peripheral portion TR. Yes. For this reason, when DIW is pumped from the rinse liquid supply unit 17 to the rinse liquid discharge nozzle 4, DIW is discharged from the rinse liquid discharge nozzle 4 toward the radially outer side of the substrate W. Thus, DIW is supplied to the surface peripheral portion TR, flows toward the outside in the radial direction of the substrate W, and is discharged out of the substrate.

  The nozzle insertion holes 5 </ b> A and 5 </ b> B are formed to have a larger diameter than the outer diameters of the nozzles 3 and 4. Therefore, it is possible to position the nozzles 3 and 4 at different positions in the horizontal direction in the internal space of the nozzle insertion holes 5A and 5B, or to move the nozzles in the nozzle insertion holes 5A and 5B. In this embodiment, as will be described in detail later, the processing position P41 of the rinsing liquid discharge nozzle 4 is set on the outer side in the radial direction of the substrate W with respect to the processing position P31 of the chemical liquid discharge nozzle 3, and A rinse liquid is supplied to the substrate end face side from the liquid contact portion Pe of the chemical liquid. Further, the second nozzle moving mechanism 43 moves the rinsing liquid discharge nozzle 4 to the rotation center side of the substrate W with the progress of the etching removal of the hardly soluble layer by the chemical liquid.

  A gas introduction port 505 is opened on the inner walls of the nozzle insertion holes 5A and 5B of the blocking member 5, and nitrogen gas can be supplied from the gas introduction port 505 to the internal spaces of the nozzle insertion holes 5A and 5B. Yes. The gas inlet 505 communicates with the gas supply unit 18 through a gas circulation space 503 formed inside the blocking member 5. Therefore, when nitrogen gas is pumped from the gas supply unit 18, the nitrogen gas is supplied to the internal spaces of the nozzle insertion holes 5A and 5B. Thereby, when the nozzles 3 and 4 are positioned at the standby positions P32 and P42, that is, when the nozzles 3 and 4 are not inserted into the nozzle insertion holes 5A and 5B, both the upper and lower openings of the nozzle insertion holes 5A and 5B are opened. Nitrogen gas is ejected from For this reason, even when the nozzle is not inserted into the nozzle insertion holes 5A and 5B, the chemical liquid and the rinse liquid are prevented from adhering to the inner walls of the nozzle insertion holes 5A and 5B.

  Next, the operation of the substrate processing apparatus configured as described above will be described with reference to FIGS. FIG. 5 is a schematic diagram showing the operation of the substrate processing apparatus of FIG. FIG. 6 is a partial cross-sectional view of FIG. In this apparatus, when an unprocessed substrate W is carried into the apparatus, the control unit 8 controls each part of the apparatus to perform a series of film removal processes on the substrate W (etching process + rinse process + drying process). Is executed. Here, the foundation layer DL is formed on the entire surface of the substrate surface Wf, and the hardly soluble layer UL is formed on the foundation layer DL (FIG. 6). In this embodiment, the substrate W is carried into the apparatus with the substrate surface Wf facing upward. Note that the blocking member 5 is located at a separated position to prevent interference with the substrate W.

  When the unprocessed substrate W is placed on the support pins 152, the blocking member 5 is lowered to the facing position and is disposed close to the substrate surface Wf. Then, nitrogen gas is discharged from the gas discharge port 502. As a result, the internal pressure of the space SP2 sandwiched between the lower surface 501 of the blocking member 5 and the substrate surface Wf is increased, and the substrate W is pressed by the support pins 152 in contact with the lower surface (back surface Wb) and applied to the spin base 15. Retained. Further, the substrate surface Wf is covered with the lower surface 501 of the blocking member 5, and is reliably blocked from the external atmosphere around the substrate. At this time, the blocking member 5 does not rotate and remains stopped.

  Subsequently, an etching process is performed on the substrate W. In this etching process, the chemical liquid discharge nozzle 3 is positioned from the standby position P32 to the processing position P31. Specifically, the chemical solution discharge nozzle 3 is moved to a position above the nozzle insertion hole 5A of the blocking member 5 along the horizontal direction. Then, the chemical discharge nozzle 3 is lowered and inserted into the nozzle insertion hole 5A. Further, as will be described later, the rinse liquid discharge nozzle 4 is positioned from the standby position P42 to the process position P41 in the same manner as the chemical liquid discharge nozzle 3 in order to perform the cover rinse process in parallel during the etching process. 5A, the distance from the rotation center A0 of the substrate W to the rinse liquid discharge nozzle 4 is longer than that of the chemical liquid discharge nozzle 3, and the rinse liquid discharge nozzle 4 is compared with the chemical liquid discharge nozzle 3 at the end face of the substrate. Located on the side. Therefore, as will be described later, the liquid contact portion Pr where the rinsing liquid discharged from the rinsing liquid discharge nozzle 4 comes into contact with the surface peripheral portion TR is closer to the substrate end surface than the liquid contact portion Pe of the chemical liquid discharged from the chemical liquid discharge nozzle 3. Located on the side.

  When the positioning of the nozzles 3 and 4 is completed in this manner, the substrate W is rotated with the blocking member 5 stopped. At this time, the substrate W pressed by the support pins 152 rotates together with the spin base 15 while being held by the spin base 15 by a frictional force generated between the support pins 152 and the substrate back surface Wb. When the rotation speed of the substrate W reaches a predetermined speed (for example, 600 rpm), the chemical solution is continuously supplied from the chemical solution discharge nozzle 3 to the surface peripheral portion TR of the rotating substrate W. As a result, the chemical liquid discharged from the chemical liquid discharge nozzle 3 is supplied to the liquid contact portion Pe, and the chemical liquid is supplied to the surface peripheral portion TR of the substrate W as shown by the hatched area in FIG. Etching removal is started.

  In this embodiment, a chemical solution such as high-concentration hydrofluoric acid is used to etch away the sparingly soluble layer UL. Therefore, as described above, the etching process is not immediately performed at the liquid-contacting portion Pe of the chemical solution. The etching process is started on the substrate end face side with respect to the liquid part Pe. Further, the hardly soluble layer UL is thin on the substrate end face side. For this reason, the poorly soluble layer UL is first removed by etching on the substrate end face side in the surface peripheral portion TR, and the base layer DL is exposed. When the etching process is continued with the base layer DL exposed, the base layer DL is etched away at a high etching rate by the chemical liquid supplied from the chemical liquid discharge nozzle 3. The underlying layer DL should not be removed by etching, and if the non-processed portion that is not covered with the poorly soluble layer UL is subjected to the etching process, the above-described problem occurs.

  Therefore, in the present embodiment, when the base layer DL is exposed, the control unit 8 operates the rinse liquid supply unit 17 to discharge the rinse liquid from the rinse liquid discharge nozzle 4. As a result, the rinsing liquid is supplied to the substrate end surface side from the liquid contact portion Pe of the chemical liquid, and the chemical liquid adhering to the exposed underlayer DL is diluted with the rinse liquid and washed away to prevent etching of the underlayer DL. Further, as shown in FIGS. 5B and 6B, the exposed portion of the base layer DL is covered with the rinsing liquid by the rinsing liquid supply, and is protected by the cover rinsing section CL. And the etching removal of the sparingly soluble layer UL is continued, protecting the exposed part of the foundation layer DL from the chemical solution by the cover rinse part CL.

  Further, when the etching removal of the hardly soluble layer UL proceeds, the exposed portion of the base layer DL spreads toward the rotation center A0 side of the substrate W. Therefore, as shown in FIG. 5C and FIG. 6C, the control unit 8 controls the second nozzle moving mechanism 43 to control the second nozzle moving mechanism 43 as the exposed portion spreads, that is, as the etching process proceeds. 4 is moved to the rotation center A0 side of the substrate W. As a result, etching removal of the sparingly soluble layer UL proceeds while the entire exposed portion is covered with the cover rinse portion CL.

  Then, when the etching removal of the hardly soluble layer UL formed on the surface peripheral portion TR is completed, the rinsing liquid supply from the rinsing liquid discharge nozzle 4 is continued, while the chemical liquid supply from the chemical liquid supply unit 16 is stopped and the chemical liquid is stopped. The discharge of the chemical solution from the discharge nozzle 3 is stopped. Thereby, the rinse process with respect to the surface peripheral part TR is performed. At this time, the rinsing liquid may be simultaneously supplied from the lower surface processing nozzle 2 to the back surface Wb of the rotating substrate W. Further, after the rinsing process, the back surface cleaning process may be performed on the substrate back surface Wb by sequentially supplying the processing liquid and the rinsing liquid from the bottom surface processing nozzle 2 in the same manner as the apparatus described in Patent Document 1.

  Thus, when the rinsing process for a predetermined time is completed, the supply of the rinsing liquid to the rinsing liquid discharge nozzle 4 is stopped, and the rinsing liquid discharge nozzle 4 is positioned from the processing position P41 to the standby position P42. Subsequently, the blocking member 5 is rotated at a high speed (for example, 1500 rpm) in the same direction at substantially the same rotational speed as that of the spin base 15. Thereby, the substrate W is dried. At this time, the nitrogen gas is supplied from the gas supply path 23 together with the supply of the nitrogen gas to the substrate surface Wf, and the nitrogen gas is supplied to the front and back surfaces of the substrate W, thereby promoting the drying process of the substrate W.

  When the drying process of the substrate W is completed, the rotation of the blocking member 5 is stopped and the rotation of the substrate W is stopped. Then, by stopping the supply of nitrogen gas from the gas discharge port 502, the pressing and holding of the substrate W to the support pins 152 is released. Thereafter, the blocking member 5 is raised, and the processed substrate W is unloaded from the apparatus.

  As described above, in the present embodiment, the substrate end surface of the hardly soluble layer UL is supplied while the chemical solution is supplied to the hardly soluble layer UL formed on the surface peripheral portion TR of the substrate W and the hardly soluble layer UL is removed by etching. A rinsing liquid is supplied to the side to form a cover rinsing portion CL, and the underlying layer DL exposed by etching removal of the hardly soluble layer UL is covered with the rinsing liquid. For this reason, it is possible to suppress the etching of the exposed portion of the underlying layer DL by the chemical solution by diluting and washing away the chemical solution flowing to the underlying layer DL. Since the etching process is performed in such a manner that the exposed base layer DL is protected by providing the cover rinse portion CL on the substrate end surface side of the hardly soluble layer UL, the hardly soluble layer formed on the surface peripheral portion TR of the substrate W. Only the layer UL can be selectively etched away.

  As described above, in the present embodiment, the underlayer DL formed on the substrate surface Wf corresponds to the “lower layer” of the present invention, and the hardly soluble layer UL formed on the underlayer DL is the “upper layer” of the present invention. It corresponds to. Further, a region exposed by etching and removing the hardly soluble layer UL in the underlayer DL, that is, an exposed portion of the underlayer DL corresponds to a “non-processed portion” of the present invention. Further, the “chemical solution supply means” of the present invention is configured by the chemical solution discharge nozzle 3 and the chemical solution supply unit 16 to supply the chemical solution to the upper layer, and the rinse solution discharge nozzle 4 and the rinse solution supply unit 17 of the present invention “ Cover rinsing means ”is configured to form a cover rinse portion CL that covers the non-processed portion with a rinsing liquid. Further, the “cover rinsing means” includes a second nozzle moving mechanism 43, and is configured to move the rinse liquid discharge nozzle 4 in the radial direction of the substrate W.

  Further, the substrate processing apparatus can perform an etching process on the substrate W on which the hardly soluble layer UL is directly formed on the substrate surface Wf. That is, the substrate substrate corresponds to the “lower layer” of the present invention, and the surface region of the substrate substrate exposed by etching and removing the hardly soluble layer UL corresponds to the “non-processed portion” of the present invention. By supplying the rinsing liquid to the substrate end surface side to form the cover rinse portion CL, it is possible to selectively remove only the hardly soluble layer UL while effectively preventing the substrate substrate from being etched.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, a so-called bevel etching process is performed in which the hardly soluble layer UL is selectively etched from the surface peripheral portion TR with respect to the substrate W on which the hardly soluble layer UL is formed on the entire surface of the base layer DL. However, the object of application of the present invention is not limited to this. That is, for example, as shown in FIGS. 7A and 8A, the hardly soluble layer UL is formed on the surface peripheral portion TR of the substrate W so that the base layer DL is exposed in the substrate end surface or in the vicinity of the substrate end surface. Even in this case, the present invention can be applied. More specifically, only the sparingly soluble layer UL is selected from the surface peripheral portion TR for the substrate W shown in FIGS. 7A and 8A by partially changing the operation of the substrate processing apparatus shown in FIG. Can be etched away. Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8.

  FIG. 7 is a schematic view showing the operation of the second embodiment of the substrate processing apparatus according to the present invention. FIG. 8 is a partial cross-sectional view of FIG. The configuration of the substrate processing apparatus according to the second embodiment is the same as that of the first embodiment as described above, and only the substrate processing operation is partially different. Hereinafter, the difference will be mainly described.

  Also in the second embodiment, as in the first embodiment, when the unprocessed substrate W is carried into the apparatus and placed on the support pins 152, the blocking member 5 is lowered to the facing position, and the substrate surface Arranged close to Wf. Then, nitrogen gas is discharged from the gas discharge port 502 to hold the substrate W on the spin base 15.

  Then, the chemical liquid discharge nozzle 3 and the rinse liquid discharge nozzle 4 are positioned at the processing positions P31 and P41, respectively (FIGS. 7A and 8A). Subsequently, the substrate W is rotated in a state where the blocking member 5 is stopped, and the rinsing liquid is discharged from the rinsing liquid discharge nozzle 4 to form the cover rinsing portion CL, and the chemical liquid is contacted from the chemical liquid discharge nozzle 3. It supplies to Pe and an etching process is started (FIG.7 (b) and FIG.8 (b)). Thus, in 2nd Embodiment, a chemical | medical solution and a rinse liquid are supplied simultaneously, a chemical | medical solution is supplied with respect to the sparingly soluble layer UL among surface peripheral part TR, and the base layer DL which is not covered with the sparingly soluble layer UL of The rinse liquid is supplied to the exposed portion, that is, the “non-processing portion” of the present invention to form the cover rinse portion CL. Then, the hardly soluble layer UL is removed by the chemical solution while protecting the exposed portion of the base layer DL with the cover rinse portion CL.

  Also in the second embodiment, as in the first embodiment, the peripheral portion of the sparingly soluble layer UL is first completely peeled off from the base layer DL, and then the rotation center A0 side of the substrate W, that is, the liquid contact portion Pe of the chemical liquid. Etching removal proceeds toward the surface, and the exposed portion of the base layer DL spreads toward the rotation center A0 side of the substrate W. Thus, as in the first embodiment, the control unit 8 controls the second nozzle moving mechanism 43 to move the rinse liquid discharge nozzle 4 to the rotation center A0 of the substrate W as the exposed portion spreads, that is, as the etching process proceeds. (Fig. 7 (c) and Fig. 8 (c)). As a result, the hardly soluble layer UL is removed by etching while the entire exposed portion of the underlying layer DL is covered with the cover rinse portion CL.

  Then, when the etching removal of the hardly soluble layer UL formed on the surface peripheral portion TR is completed, after the rinsing process and the drying process are performed as in the first embodiment, the processed substrate W is unloaded from the apparatus. The

  As described above, according to the second embodiment, the rinsing liquid is supplied to the substrate end surface side of the hardly soluble layer UL, and the exposed portion of the foundation layer DL is protected by the cover rinse portion CL, while the hardly soluble layer UL is protected. Since the etching process is performed, only the hardly soluble layer UL formed on the surface peripheral portion TR of the substrate W can be selectively removed by etching without etching the base layer DL with the chemical solution.

  Moreover, in the said 2nd Embodiment, although the etching process was performed with respect to the board | substrate W in which the poorly soluble layer UL was formed on the base layer DL, the poorly soluble layer UL was directly formed on the board | substrate surface Wf. Etching can be performed on the substrate W by the substrate processing apparatus. That is, in this case, the substrate base corresponds to the “lower layer” of the present invention, and the surface area of the substrate surface Wf where the hardly soluble layer UL is not formed and the surface area of the substrate base exposed by etching away the hardly soluble layer UL. Corresponds to the “non-processed portion” of the present invention, and the effect of etching the substrate substrate by forming the cover rinse portion CL from the start of the etching process to the end of the etching as in the second embodiment. Thus, only the hardly soluble layer UL can be selectively removed by etching. This also applies to the case where the substrate processing apparatus performs an etching process on the substrate W on which the hardly soluble layer UL is directly formed on the entire substrate surface Wf. That is, it is difficult to effectively prevent the substrate base from being etched by forming the cover rinse portion CL in the surface region of the substrate base exposed by the etching removal of the hardly soluble layer UL as in the first embodiment. Only the soluble layer UL can be selectively removed by etching.

  In the above embodiment, DIW is used as the rinsing liquid. However, other liquids may be used as the rinsing liquid, and any liquid may be used as long as it is a liquid that can protect the base layer DL and the substrate substrate. Can be used.

  In the above embodiment, the W layer is formed as the upper layer (hardly soluble layer UL), and the Th-Ox (thermal oxidation) layer is formed as the lower layer (underlying layer DL), and the Th-Ox layer (non-treated portion) The etching process is performed on the substrate W whose etching selectivity is 3.4 with respect to the etching selectivity of the W layer. The object of application of the present invention is not limited to the substrate W having such an etching selectivity, but the present invention is applied to a substrate having a lower layer etching selectivity of 3.4 or less with respect to an upper layer etching selectivity. Is particularly effective.

  In the above embodiment, the direction extending from the rotation center A0 to the processing position P31 (chemical solution supply position) of the chemical liquid discharge nozzle 3 and the processing position P41 (rinsing liquid supply position) of the rinse liquid discharge nozzle 4 from the rotation center A0 in plan view. The angle formed by the extending direction is 180 °, but the angle is not limited to this.

  Moreover, in the said embodiment, when positioning the nozzles 3 and 4 in the process position P31 and P41 which can supply a chemical | medical solution and a rinse liquid to the surface peripheral part TR, respectively, nozzle insertion hole 5A, 5B formed in the interruption | blocking member 5 The nozzles 3 and 4 are inserted into the nozzle insertion holes 5 and 5B, but it is not always necessary to insert the nozzles 3 and 4 into the nozzle insertion holes 5A and 5B. For example, a blocking member having a planar size smaller than the planar size of the substrate W may be disposed to face the substrate surface Wf, and the nozzles 3 and 4 may be disposed close to the side wall of the blocking member. Further, only the nozzles 3 and 4 may be positioned on the substrate surface Wf side without disposing the blocking member 5 opposite to the substrate surface Wf.

  Further, in the above embodiment, the substrate W is pressed and supported by the support member such as the support pin 152 that contacts the back surface Wb of the substrate W to hold the substrate W. However, the holding member such as the chuck pin is used as the outer peripheral end portion of the substrate W. The substrate W may be held in contact with the substrate.

  In the above embodiment, the substrate processing apparatus is equipped with one chemical solution discharge nozzle 3 and one rinse solution discharge nozzle 4, but the number of nozzles is not limited to one, and a plurality of nozzles are provided. Also good.

  Further, with respect to the nozzle insertion holes of the blocking member 5, in the above embodiment, two nozzle insertion holes are formed in the blocking member 5 corresponding to the nozzles 3 and 4, but three or more nozzle insertion holes are formed. May be. For example, three or more nozzle insertion holes may be formed at different positions formed by a direction extending from the rotation center A0 to the first processing position and a direction extending from the rotation center A0 to the second processing position in plan view. Good. In particular, although the formation state and dimensions of the hardly soluble layer and the underlayer may differ depending on the substrate W, the nozzle insertion position in advance, the range in which the rinse liquid discharge nozzle 4 can move within the nozzle insertion hole, and the like are inserted. If each hole is different, the nozzles 3 and 4 are appropriately inserted into any of the three or more nozzle insertion holes according to the formation state or dimensions of the hardly soluble layer or the base layer, and the process is performed. The cover rinse portion CL can be formed at a position corresponding to the substrate W, can be applied to various substrates W, and versatility can be improved.

  The present invention relates to a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, a glass substrate for plasma display, a substrate for FED (Field Emission Display), a substrate for optical disk, a substrate for magnetic disk, a substrate for magneto-optical disk, etc. The present invention can be applied to a substrate processing apparatus and a substrate processing method for etching and removing a thin film adhering to the peripheral edge portion of the surface of the substrate.

DESCRIPTION OF SYMBOLS 3 ... Chemical liquid discharge nozzle 4 ... Rinse liquid discharge nozzle 16 ... Chemical liquid supply unit 17 ... Rinse liquid supply unit 43 ... 2nd nozzle moving mechanism CL ... Cover rinse part DL ... Underlayer (lower layer)
P31 ... Processing position (chemical solution supply position)
P41 ... Processing position (rinsing liquid supply position)
TR ... surface peripheral part UL ... poorly soluble layer (upper layer)
Wf ... substrate surface W ... substrate

Claims (7)

In the substrate processing apparatus for removing the upper layer formed on the peripheral edge of the surface of the rotating substrate,
Chemical supply means for supplying a chemical to the upper layer and etching away the upper layer;
Cover rinsing means for supplying a rinsing liquid to the substrate end surface side of the liquid contact portion, in which the chemical solution contacts the upper layer, and covering the non-treated portion that is not covered with the upper layer of the surface peripheral edge portion with the rinse liquid. A substrate processing apparatus comprising:   The substrate processing apparatus according to claim 1, wherein the cover rinsing means supplies the rinsing liquid in a direction from the upper center of rotation of the substrate toward the end face of the substrate.   The substrate processing apparatus according to claim 1, wherein the cover rinsing unit includes a nozzle that discharges the rinsing liquid to the non-processing unit and a moving mechanism that moves the nozzle in a radial direction of the substrate.   The substrate according to claim 3, wherein the moving mechanism moves the nozzle toward the rotation center side of the substrate as the non-processed portion spreads from the substrate end surface side toward the rotation center side of the substrate as the etching process proceeds. Processing equipment.   The chemical liquid supply position where the chemical liquid supply means supplies the chemical liquid and the rinse liquid supply position where the cover rinse means supplies the rinse liquid are arranged on opposite sides of the rotation center of the substrate. Item 5. The substrate processing apparatus according to any one of Items 1 to 4. An etching step of supplying a chemical solution to the upper layer formed on the peripheral edge of the surface of the rotating substrate and etching away the upper layer;
During the etching step, the chemical solution contacts the upper layer, and a rinse liquid is supplied to the substrate end surface side of the liquid contact portion, and the non-processed portion that is not covered with the upper layer in the surface peripheral portion is removed by the rinse liquid. And a cover rinsing step for covering with a substrate.   The substrate processing method according to claim 6, wherein an etching selectivity of the non-processed portion is 3.4 or less with respect to an etching selectivity of the upper layer.

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