JP2007317792A - Substrate-treating apparatus and substrate treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress electrostatic charge of a substrate due to treatment in a substrate-treating apparatus for supplying a treatment liquid to the substrate for treatment. <P>SOLUTION: The substrate-treating apparatus 1 comprises: a gas-liquid mixer 43 for generating water where carbon dioxide is dissolved that is a cleaning liquid by dissolving carbon dioxide in demineralized water; a discharge section 3 that is a two fluid nozzle for discharging a droplet of cleaning liquid toward the substrate 9; and a toroidal induction electrode 6 arranged near a discharge port 31 at the discharge section 3. In the substrate-treating apparatus 1, the specific resistance of the water where carbon dioxide is dissolved is set to not less than 1×10<SP>2</SP>Ω and not more than 4×10<SP>3</SP>Ωm. In the substrate-treating apparatus 1, by giving a potential difference between the induction electrode 6, and a cleaning liquid pipe at the discharge section 3, charge is induced in the cleaning liquid of which the specific resistance is smaller than that of the demineralized water, and the substrate 9 is cleaned with a droplet of cleaning liquid, thus suppressing the electrostatic charge of the substrate 9 due to cleaning treatment. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for processing a substrate by supplying a processing liquid to the substrate.

  Conventionally, in a manufacturing process of a semiconductor substrate (hereinafter simply referred to as “substrate”), various processes are performed by supplying a processing liquid to the substrate. For example, in the substrate cleaning process, particles attached to the surface of the substrate are removed by spraying a cleaning liquid such as pure water onto the substrate.

  By the way, in such a cleaning process, it is known that the entire surface of the substrate is charged by contact between the substrate having an insulating film formed on the surface and pure water having a high specific resistance. For example, the substrate is negatively charged when an oxide film is formed on the substrate surface, and positively charged when a resist film is formed on the substrate surface. Here, if the charge amount of the substrate becomes large, there is a risk of damage of the wiring due to reattachment of particles or discharge during or after cleaning. Thus, various techniques for suppressing the charging of the substrate have been proposed for the substrate processing apparatus.

  For example, in Patent Document 1, in a cleaning apparatus that supplies a cleaning liquid to a rotating substrate and performs cleaning, cleaning is performed while ionized nitrogen gas is purged into a processing space on the substrate, thereby suppressing charging of the substrate surface. Techniques to do this are disclosed. Further, in Patent Document 2, in a cleaning apparatus that immerses and cleans a substrate in a processing tank in which a cleaning liquid is stored, a liquid that is sprayed onto the substrate when the cleaning liquid is replaced is obtained from pure water by dissolving carbon dioxide gas in pure water. Also disclosed is a technique for suppressing the charging of the substrate surface by using carbon dioxide-dissolved water with reduced specific resistance.

  In Patent Document 3, pure water is ejected from a nozzle at a high speed to generate fine droplets of pure water charged by fluid friction with the nozzle, and the droplets are brought into contact with the charged substance. A static eliminator that removes static electricity is disclosed, and a charged semiconductor substrate after cleaning is cited as an application target of the static eliminator.

On the other hand, Non-Patent Document 1 describes an experiment relating to a mechanism for generating a charged mist generated when a jet of pure water ejected from a nozzle collides with a silicon wafer. In the apparatus used for the experiment, the charge amount of the charged fog is changed by controlling the charge amount of the jet by arranging the induction electrode in the pure water ejection path.
JP 2002-184660 A JP 2005-183791 A Japanese Patent Laid-Open No. 10-149893 Kazuaki Asano, Hirofumi Shimokawa, “Charged fog due to collision between water jet and silicon wafer”, Proceedings of the Electrostatic Society of Japan '00 (2000.3), Electrostatic Society, March 2000, p. 25-26

  By the way, in the cleaning process in the ionized gas atmosphere as in Patent Document 1, cleaning is performed using pure water having a high specific resistance, so that the substrate becomes highly charged. In addition, it is difficult to continuously and efficiently supply the ionized gas to the substrate surface, and there is a limit to the suppression of charging of the substrate during the cleaning process. On the other hand, in the apparatuses of Patent Document 2 and Patent Document 3, charging of the substrate during the cleaning process cannot be suppressed.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to suppress charging of a substrate due to processing in a substrate processing apparatus that supplies a processing liquid to a substrate for processing.

  The invention described in claim 1 is a substrate processing apparatus for processing a substrate by supplying a processing liquid to the substrate, and discharging the processing liquid in which carbon dioxide gas is dissolved in pure water toward the main surface of the substrate. A discharge unit, a treatment liquid supply unit that guides the processing liquid to the discharge unit, and is disposed in the vicinity of the discharge port of the discharge unit or at the position of the discharge port while being electrically insulated from the discharge unit; An induction electrode that induces electric charge in the treatment liquid in the vicinity of the discharge port by applying a potential difference between the treatment liquid supply part and the conductive liquid contact part.

Invention of Claim 2 is the substrate processing apparatus of Claim 1, Comprising: The specific resistance of the said process liquid is 1 * 10 < ² > (ohm) m or more and 4 * 10 < ³ > (ohm) m or less.

The invention according to claim 3 is a substrate processing apparatus for processing a substrate by supplying a processing solution to the substrate, and a processing solution having a specific resistance of 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less is applied to the substrate. A discharge portion that discharges toward the main surface; a treatment liquid supply portion that guides the treatment liquid to the discharge portion; and a portion near or at the discharge port of the discharge portion while being electrically insulated from the discharge portion. And an induction electrode that induces an electric charge in the processing liquid in the vicinity of the discharge port by applying a potential difference between the discharge section and the conductive liquid contact section of the processing liquid supply section.

A fourth aspect of the present invention is the substrate processing apparatus according to the third aspect, wherein the specific resistance of the processing liquid is 5 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less.

  The invention according to claim 5 is the substrate processing apparatus according to claim 3 or 4, wherein the processing liquid is a liquid obtained by dissolving a gas in pure water.

  A sixth aspect of the present invention is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the discharge section ejects droplets of the processing liquid toward the substrate.

  The invention according to claim 7 is the substrate processing apparatus according to claim 6, wherein the discharge unit mixes the processing liquid and the carrier gas in the discharge unit or in the vicinity of the discharge port. To produce the droplets of the treatment liquid.

  The invention according to claim 8 is a substrate processing method for processing a substrate by supplying a processing liquid to the substrate, wherein a) a processing liquid in which carbon dioxide gas is dissolved in pure water is connected to the processing liquid supply unit. A step of discharging from the discharged portion toward the main surface of the substrate; b) an induction electrode disposed in the vicinity of the discharge port of the discharge portion or at the position of the discharge port while being electrically insulated from the discharge portion; A step of inducing a charge in the treatment liquid in the vicinity of the discharge port in parallel with the step a) by applying a potential difference between the discharge part or the conductive liquid contact part of the treatment liquid supply part. Prepare.

The invention according to claim 9 is a substrate processing method for processing a substrate by supplying a processing solution to the substrate, and a) a processing solution having a specific resistance of 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less. A step of discharging toward the main surface of the substrate from the discharge unit connected to the treatment liquid supply unit; b) in the vicinity of the discharge port of the discharge unit or at the position of the discharge port while being electrically insulated from the discharge unit. By applying a potential difference between the arranged induction electrode and the conductive liquid contact part of the discharge part or the treatment liquid supply part, the treatment liquid is disposed in the vicinity of the discharge port in parallel with the step a). And a step of inducing charges.

  In the present invention, it is possible to suppress charging of the substrate by discharging the processing liquid toward the substrate.

FIG. 1 is a diagram showing a configuration of a substrate processing apparatus 1 according to a first embodiment of the present invention. The substrate processing apparatus 1 supplies particles with a cleaning liquid to a semiconductor substrate 9 (hereinafter simply referred to as “substrate 9”) having an insulating film formed on the surface thereof to perform cleaning processing. The substrate cleaning apparatus removes the foreign matter. In the present embodiment, carbon dioxide-dissolved water obtained by dissolving carbon dioxide (CO ₂ ) in pure water is used as the cleaning liquid. In the present embodiment, the substrate 9 having an oxide film formed on the surface is cleaned.

  As shown in FIG. 1, the substrate processing apparatus 1 is disposed above the substrate holding unit 2 that holds the substrate 9 from the lower side and the main surface on the upper side of the substrate 9 (hereinafter referred to as “upper surface”). The discharge unit 3 that discharges the cleaning liquid toward the surface, the circular cleaning liquid supply unit (that is, the processing liquid supply unit) 41 that guides the cleaning liquid to the discharge unit 3, and the cleaning liquid supply unit 41 lead the carrier gas to the discharge unit 3 separately. The gas supply unit 42, the gas-liquid mixer 43 that generates cleaning liquid (that is, carbon dioxide-dissolved water), and the non-conductive support member 35 are fixed to the discharge unit 3. The discharge electrode 3 disposed in the vicinity of the discharge port 31 of the discharge unit 3 and the discharge unit moving mechanism 5 that moves the discharge unit 3 relative to the substrate 9 along with the induction electrode 6 parallel to the upper surface of the substrate 9. Is provided. In FIG. 1, for convenience of illustration, a part of the substrate holding unit 2 is drawn in cross section.

  The substrate holding unit 2 includes a chuck 21 that holds the substantially disk-shaped substrate 9 from the lower side and the outer peripheral side, a rotating mechanism 22 that rotates the substrate 9 together with the chuck 21, and a processing cup 23 that covers the outer periphery of the chuck 21. . The rotation mechanism 22 includes a shaft 221 connected to the lower side of the chuck 21 and a motor 222 that rotates the shaft 221, and the substrate 9 rotates together with the shaft 221 and the chuck 21 by driving the motor 222. The processing cup 23 is disposed on the outer periphery of the chuck 21 to prevent the cleaning liquid supplied on the substrate 9 from scattering to the periphery, and the processing cup 23 is provided below the processing cup 23 and supplied to the substrate 9. A discharge port 232 for discharging the cleaning liquid is provided.

  The discharge unit moving mechanism 5 includes an arm 51 having the discharge unit 3 fixed at the tip, and a motor 52 that swings the arm 51. In the substrate processing apparatus 1, when the motor 52 is driven, the discharge unit 3 reciprocates in a circular arc shape that is close to a straight line parallel to the upper surface of the substrate 9 together with the arm 51.

  The gas-liquid mixer 43 is connected to the cleaning liquid supply unit 41. The gas-liquid mixer 43 includes a pure water supply pipe 44 and carbon dioxide gas connected to a pure water supply source and a carbon dioxide supply source (not shown), respectively. A supply pipe 45 is connected. Inside the gas-liquid mixer 43, a gas permeable and liquid impermeable gas dissolving membrane formed by a hollow fiber separation membrane or the like is provided. In the gas-liquid mixer 43, pure water and carbon dioxide are individually supplied to two supply chambers separated by a gas dissolution film, and the pressure of carbon dioxide is made higher than the pressure of pure water. Carbon dioxide gas permeates through the gas-dissolving membrane and dissolves in pure water to generate carbon dioxide-dissolved water. The carbon dioxide-dissolved water is supplied to the discharge unit 3 as a cleaning liquid via the cleaning liquid supply unit 41. Note that unnecessary gas dissolved in pure water is degassed by a vacuum pump (not shown).

In the gas-liquid mixer 43, the supply pressure or the like of carbon dioxide or pure water is controlled so that the specific resistance of the carbon dioxide dissolved water becomes a predetermined value. The specific resistance of the carbon dioxide-dissolved water is preferably 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less (more preferably 5 × 10 ² Ωm or more and 4 or more from the viewpoint of simplification of the gas-liquid mixer 43). × 10 ³ Ωm or less), and in this embodiment, about 1 × 10 ³ Ωm.

FIG. 2 is a longitudinal sectional view showing the vicinity of the discharge unit 3. In FIG. 2, the support member 35 is not shown for the sake of illustration. As shown in FIG. 2, the discharge unit 3 is an internal mixing type two-fluid nozzle, and includes a circular cleaning liquid pipe 32 centered on the central axis 30 of the discharge unit 3 (also the central axis of the discharge port 31). Prepare inside. The cleaning liquid pipe 32 is connected to the cleaning liquid supply section 41 at the upper part of the discharge section 3, and the space inside the cleaning liquid pipe 32 becomes a cleaning liquid flow path 321 through which the cleaning liquid supplied from the cleaning liquid supply section 41 flows. A space between the outer wall 34 of the discharge unit 3 and the cleaning liquid pipe 32 is a carrier gas (for example, nitrogen (N ₂ ) gas or air) supplied from the gas supply unit 42, and in this embodiment, nitrogen gas ) Flows, and the gas flow path 33 surrounds the cleaning liquid flow path 321.

  In the discharge unit 3, the tip of the cleaning liquid pipe 32 is located inside the discharge port 31 (that is, the upper side in FIG. 2), and the cleaning liquid ejected from the cleaning liquid pipe 32 is separated from the carrier gas in the discharge part 3. By mixing, minute droplets of the cleaning liquid are generated and ejected together with the carrier gas from the discharge port 31 toward the substrate 9 (see FIG. 1). The inner diameter of the discharge port 31 is about 2 to 3 mm.

  The cleaning liquid pipe 32 (that is, the part forming the cleaning liquid flow path 321 in the discharging section 3) and the cleaning liquid supply section 41 connected to the cleaning liquid pipe 32 are both conductive carbon (preferably amorphous carbon). Or glassy carbon such as glassy carbon) or a conductive resin (for example, conductive PEEK (polyether ether ketone) or conductive PTFE (polytetrafluoroethylene)). In the present embodiment, the cleaning liquid pipe 32 and the cleaning liquid supply unit 41 are formed of glassy conductive carbon. Glassy carbon is a hard carbon material having a homogeneous and dense structure, and is excellent in electrical conductivity, chemical resistance, heat resistance, and the like.

  In the substrate processing apparatus 1, the cleaning liquid pipe 32 and the cleaning liquid supply unit 41 are one cleaning liquid supply pipe that supplies the cleaning liquid to the substrate 9, and the entire cleaning liquid supply pipe is a conductive liquid contact part that contacts the cleaning liquid. . In the substrate processing apparatus 1, a conductive wire 82 is connected to a portion near the tip of the cleaning liquid pipe 32, and as shown in FIG. 1, the cleaning liquid pipe 32 (see FIG. 2) and the cleaning liquid supply unit 41 are connected via the conductive wire 82. Is grounded.

  As shown in FIG. 2, the induction electrode 6 is an annular plate-like member surrounding the central axis 30 of the discharge port 31, and has an outer diameter of about 15 mm and an inner diameter of about 8 mm. The distance between the induction electrode 6 and the discharge port 31 in the direction of the central axis 30 is about 3 to 4 mm, and conductive carbon (preferably glassy carbon such as amorphous carbon or glassy carbon) or conductive resin (for example, The induction electrode 6 formed of conductive PEEK or conductive PTFE and the discharge part 3 are electrically insulated.

  In the substrate processing apparatus 1 shown in FIG. 1, the induction electrode 6 is electrically connected to a power supply 81 outside the substrate processing apparatus 1, so that the cleaning liquid pipe 32 (see FIG. 2) that is a conductive liquid contact portion and the induction are used. A potential difference is applied to the electrode 6. As a result, a charge is induced in the cleaning liquid in the vicinity of the discharge port 31 of the discharge unit 3, and a droplet of the cleaning liquid having the charge is ejected from the discharge unit 3.

  Next, cleaning of the substrate 9 by the substrate processing apparatus 1 will be described. FIG. 3 is a diagram showing a flow of cleaning the substrate 9. In the substrate processing apparatus 1 shown in FIG. 1, first, after the substrate 9 is held by the chuck 21 of the substrate holding unit 2, the motor 222 of the rotation mechanism 22 is driven to start the rotation of the substrate 9 (step S11, S12).

  Subsequently, a potential difference is applied between the induction electrode 6 and the cleaning liquid tube 32 of the discharge unit 3, whereby charges are induced in a portion near the discharge port 31 of the discharge unit 3 (that is, the tip of the cleaning liquid tube 32). (Step S13). In the present embodiment, a positive charge is induced in the vicinity of the discharge port 31 of the discharge unit 3 by applying a potential of about −1000 V to the induction electrode 6.

  Next, the discharge unit moving mechanism 5 is driven to start the movement (ie, swing) of the discharge unit 3 and the induction electrode 6 (step S14). In the substrate processing apparatus 1, a positive charge is induced in the cleaning liquid in the vicinity of the discharge port 31 by supplying the cleaning liquid and nitrogen gas to the discharge unit 3 in a state where the charge is induced in the vicinity of the discharge port 31. At the same time, minute droplets of the cleaning liquid are generated, and the droplets of the cleaning liquid in which positive charges are induced are ejected (that is, discharged) toward the upper surface of the substrate 9 to clean the substrate 9 (step S15).

  The discharge unit 3 and the induction electrode 6 discharge the cleaning liquid toward the upper surface of the substrate 9 above the rotating substrate 9 and between the center and the peripheral portion of the substrate 9 in parallel with the upper surface of the substrate 9. By repeating reciprocating movement at a constant speed in an arc shape close to a straight line, droplets of the cleaning liquid are ejected onto the entire upper surface of the substrate 9 and foreign matters such as particles adhering to the upper surface are removed. In the substrate processing apparatus 1, while the droplets of the cleaning liquid are ejected to the substrate 9, the induction of the charge to the cleaning liquid in the vicinity of the discharge port 31 by the induction electrode 6 is continuously performed in parallel.

  When the ejection unit 3 is moved a predetermined number of times and the entire top surface is cleaned while the ejection of the cleaning liquid droplets onto the substrate 9 is continued, the ejection of the cleaning liquid from the ejection unit 3 and the ejection unit 3 is stopped, and application of a potential difference between the induction electrode 6 and the cleaning liquid pipe 32 (that is, induction of electric charge in the vicinity of the discharge port 31) is also stopped (step S16). Thereafter, the rotation of the substrate 9 is continued and dried, and then the rotation of the substrate 9 is stopped (step S17). The substrate 9 is unloaded from the substrate processing apparatus 1 and the cleaning process for the substrate 9 is completed (step S17). S18).

  In the substrate processing apparatus 1, fine droplets of the cleaning liquid collide with the upper surface of the substrate 9 at a high speed, so that the fine pattern formed on the upper surface is not damaged, and the minute matter such as organic matter adhering to the upper surface is damaged. Particles can be efficiently removed.

  FIG. A is a diagram showing a potential distribution on the upper surface of the substrate 9 after the cleaning process by the substrate processing apparatus 1. FIG. B is a diagram illustrating a potential distribution on the upper surface of the substrate when pure water is used as the cleaning liquid and cleaning is performed without performing charge induction on the cleaning liquid. FIG. C is a diagram showing a potential distribution on the upper surface of the substrate when carbon dioxide-dissolved water is used as the cleaning liquid and cleaning is performed without performing charge induction on the cleaning liquid.

  FIG. In B, the potential in the vicinity of the central portion of the substrate 9 having the largest charge amount (that is, the absolute value of the potential) is about −13V. In addition, FIG. A and FIG. Also in C, the upper side in the figure represents a negative potential. Note that the substrate is hardly charged in a state before cleaning, and the potential is considered to have been generated by the cleaning process by the substrate processing apparatus. FIG. B and FIG. As shown in C, when carbon dioxide-dissolved water having a specific resistance lower than that of pure water is used as the cleaning liquid, charging of the substrate surface caused by the cleaning process is reduced.

  In the substrate processing apparatus 1 according to the present embodiment, carbon dioxide-dissolved water having a specific resistance lower than that of pure water is used as a cleaning liquid, and the polarity is opposite to the substrate potential after cleaning when cleaning is performed without applying a potential difference. 4. By cleaning the substrate 9 with the droplets of the cleaning liquid in which the charges (ie, positive charges) are induced, FIG. A thru | or FIG. As shown in C, charging of the substrate 9 during and after cleaning (that is, charging of the substrate 9 by the cleaning process) is suppressed compared to cleaning without charge induction using pure water or carbon dioxide-dissolved water as a cleaning liquid. can do.

  In the substrate processing apparatus 1, by providing the induction electrode 6 in the vicinity of the discharge port 31 of the discharge unit 3, it is possible to easily realize charge induction for the cleaning liquid droplets while simplifying the structure of the substrate processing apparatus 1. .

  In the substrate processing apparatus 1, charging of the substrate 9 can be further suppressed by continuously inducing charge to the ejection unit 3 while the substrate 9 is being cleaned. Furthermore, the induction electrode 6 is formed in an annular shape surrounding the central axis 30 of the discharge port 31, so that electric charges can be induced approximately evenly in the vicinity of the discharge port 31 without disturbing the discharge of the cleaning liquid from the discharge port 31. it can. As a result, it is possible to induce charges almost uniformly with respect to a large number of droplets of the cleaning liquid, and to suppress charging almost uniformly over the entire surface of the substrate 9.

  In the substrate processing apparatus 1, since the carbon dioxide dissolved in the cleaning liquid is removed from the substrate 9 in the drying process after cleaning, the rinsing process of the substrate 9 becomes unnecessary, and the cleaning process of the substrate 9 is simplified. Can do. Further, by using a two-fluid nozzle as the discharge unit 3, it is possible to easily generate droplets of the cleaning liquid, and it is possible to reduce the size of the mechanism related to the generation and ejection of the droplets.

  In the substrate processing apparatus 1, instead of carbon dioxide-dissolved water, a liquid obtained by dissolving a rare gas such as xenon (Xe) or a gas such as methane gas in pure water may be used as the cleaning liquid. Also in this case, the specific resistance of the cleaning liquid is lower than that of pure water, and by cleaning the substrate 9 with the droplets of the cleaning liquid in which charges are induced, charging of the substrate 9 due to the cleaning process can be suppressed. Further, since the gas dissolved in the cleaning liquid is removed from the substrate 9 in the drying process after cleaning, the rinsing process of the substrate 9 becomes unnecessary, and the cleaning process of the substrate 9 can be simplified.

  Next, a substrate processing apparatus according to a second embodiment of the present invention will be described. FIG. 5 is a diagram showing a configuration of the substrate processing apparatus 1a. As shown in FIG. 5, the substrate processing apparatus 1a includes a mixing valve 43a and a chemical solution supply pipe 45a in place of the gas-liquid mixer 43 and the carbon dioxide supply pipe 45 shown in FIG. Other configurations are the same as those in FIGS. 1 and 2, and the same reference numerals are given in the following description.

In the present embodiment, dilute hydrochloric acid is supplied from the chemical solution supply pipe 45a to the mixing valve 43a, and a small amount of dilute hydrochloric acid is mixed with pure water in the mixing valve 43a, so that the cleaning liquid has a lower specific resistance than pure water. Is generated and supplied to the discharge unit 3 via the cleaning liquid supply unit 41. In the present embodiment, the specific resistance of the cleaning liquid is 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less (more preferably, 5 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less).

  The flow of cleaning the substrate 9 by the substrate processing apparatus 1a is the same as that of the first embodiment (see FIG. 3), and a potential is generated between the induction electrode 6 and the cleaning liquid pipe 32 (see FIG. 2) of the discharge unit 3. Is applied to the cleaning liquid having a specific resistance lower than that of pure water, and the substrate 9 is cleaned with the liquid droplets of the cleaning liquid, thereby cleaning without charge induction using pure water or the like as the cleaning liquid. In comparison, charging of the substrate 9 due to the cleaning process can be suppressed.

In the substrate processing apparatus 1a, the specific resistance of the cleaning liquid is set to 1 × 10 ² Ωm or more (preferably 5 × 10 ² Ωm or more), thereby preventing the acidity of the cleaning liquid from becoming excessively strong. The influence of the damage of the wiring of the board | substrate 9 by contact, etc. can be prevented. Further, by setting the specific resistance of the cleaning liquid to 4 × 10 ³ Ωm or less, charging of the substrate 9 can be further suppressed as compared with cleaning with pure water or the like having a high specific resistance.

  In the substrate processing apparatus 1a, instead of dilute hydrochloric acid, an aqueous solution obtained by slightly mixing a chemical solution such as an ammonia solution or a hydrogen peroxide solution with pure water may be used as a cleaning solution.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  In the substrate processing apparatus according to the above-described embodiment, the distance between the induction electrode 6 in the direction of the central axis 30 and the discharge port 31 of the discharge unit 3 can induce charge in the vicinity of the discharge port 31 using a realistic power supply. If it is a short distance, it may be different from the distance shown in the above embodiment. The induction electrode 6 may be disposed at the position of the discharge port 31 of the discharge unit 3 (that is, around the discharge port 31) in the direction of the central axis 30.

  In the substrate processing apparatus, the shape of the induction electrode is not necessarily limited to an annular plate shape. FIG. 6 is a longitudinal sectional view showing the vicinity of the discharge unit 3 of the substrate processing apparatus including the induction electrode 6a having another shape. The induction electrode 6a has an annular shape centering on the central axis 30 of the discharge port 31 of the discharge unit 3, and surrounds the periphery of the discharge port 31 and has an inclined surface 61 that is inclined with respect to the central axis 30 of the discharge port 31 inside ( That is, it is on the central axis 30 side). The inclined surface 61 is a part of a conical surface having an apex on the central axis 30 of the discharge port 31 on the substrate 9 (see FIG. 1) side of the discharge port 31. The angle formed is 45 °. Further, the position of the outer edge 611 of the inclined surface 61 in the direction of the central axis 30 coincides with the position of the discharge port 31 in the direction of the central axis 30.

  By forming the induction electrode 6 a in the above-described shape, the gap between the central axis 30 and the inclined surface 61 in the direction perpendicular to the central axis 30 in an arbitrary cross section of the inclined surface 61 of the induction electrode 6 a by the plane including the central axis 30. The distance becomes longer between the ejection part 3 and the upper surface of the substrate 9 as it approaches the ejection port 31. As a result, the area of the induction electrode 6 at a position close to the discharge port 31 can be increased, so that charges can be efficiently induced in the cleaning liquid. Further, since the inclined surface 61 is a part of the conical surface, the inclined surface 61 can be easily formed by cutting or the like.

  The liquid contact portion of the discharge unit 3 to which a potential difference is applied between the induction electrode and the induction electrode is not necessarily provided in the cleaning liquid pipe 32. For example, the cleaning liquid supply unit 41 may be grounded via the conductive wire 82. Further, the application of the potential difference between the induction electrode and the liquid contact part on the discharge unit 3 side may be performed, for example, by grounding the induction electrode and connecting the liquid contact part to the power source 81. These two electrodes may be connected to the induction electrode and the liquid contact part, respectively. However, from the viewpoint of simplifying the structure of the substrate processing apparatus, it is preferable that the liquid contact portion is grounded and the induction electrode is connected to the power source 81 as in the above embodiment.

  In the substrate processing apparatus 1 according to the first embodiment, the gas-liquid mixer 43 that generates carbon dioxide-dissolved water is not necessarily provided, and carbon dioxide-dissolved water generated by another apparatus is discharged as a cleaning liquid. It may be supplied to the section 3. Similarly, in the substrate processing apparatus 1 a according to the second embodiment, the mixing valve 43 a is not necessarily provided, and the cleaning liquid generated by another apparatus may be supplied to the discharge unit 3.

  The discharge unit 3 is not necessarily limited to the internal mixing type two-fluid nozzle. For example, the cleaning liquid and the carrier gas are individually ejected to the outside of the discharge unit, and mixed in the vicinity of the discharge port 31 to mix the cleaning liquid. It may be an externally mixed two-fluid nozzle that generates drops. Further, in the substrate processing apparatus, the droplets of the cleaning liquid generated by another apparatus may be supplied to the discharge unit 3 and the droplets may be ejected from the discharge unit 3 together with the carrier gas. May be supplied and ejected as droplets.

  In the substrate processing apparatus, the droplets of the cleaning liquid do not necessarily have to be discharged from the discharge unit 3. For example, the substrate 9 may be cleaned by discharging the cleaning liquid in a columnar flow, and ultrasonic waves may be generated. The substrate 9 may be cleaned by discharging the applied cleaning liquid. As described above, since the substrate processing apparatus can suppress charging due to cleaning of the substrate 9, it is particularly suitable for cleaning with droplets in which the charge amount of the substrate 9 is larger than cleaning with a liquid column.

  In the substrate processing apparatus according to the above embodiment, the polarity of the potential of the substrate and the amount of charge generated by the cleaning are determined depending on the type of the substrate (for example, the type of insulating film and the type of wiring metal on the upper surface of the semiconductor substrate, and combinations thereof). Therefore, the potential difference applied between the induction electrode and the ejection unit 3 in the substrate processing apparatus is variously changed according to the type of the substrate. For example, when a resist film is formed on the substrate, the upper surface of the substrate is positively charged by the cleaning, so that a positive voltage is applied to the induction electrode and a negative charge is induced in the cleaning liquid.

  The substrate processing apparatus according to the above embodiment may be used for various processes other than the cleaning of the substrate. For example, the substrate processing apparatus may be used for a rinsing process of the substrate after the chemical solution cleaning. In this case, a rinsing liquid such as pure water is used as a processing liquid supplied to the substrate. Further, the substrate processing apparatus may be used for processing various substrates other than the semiconductor substrate such as a glass substrate used for a printed wiring board or a flat panel display device.

It is a figure which shows the substrate processing apparatus which concerns on 1st Embodiment. It is a longitudinal cross-sectional view which shows the discharge part vicinity. It is a figure which shows the flow of washing | cleaning of a board | substrate. It is a figure which shows the electric potential distribution in the upper surface of a board | substrate. It is a figure which shows the electric potential distribution in the upper surface of the board | substrate after washing | cleaning without the charge induction by a pure water. It is a figure which shows the electric potential distribution in the upper surface of the board | substrate after washing | cleaning without the charge induction by a carbon dioxide dissolved water. It is a figure which shows the substrate processing apparatus which concerns on 2nd Embodiment. It is a longitudinal section showing other examples of an induction electrode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Substrate processing apparatus 3 Discharge part 6,6a Induction electrode 9 Substrate 31 Discharge port 32 Cleaning liquid pipe 41 Cleaning liquid supply part S11-S18 Step

Claims (9)

A substrate processing apparatus for processing a substrate by supplying a processing liquid to the substrate,
A discharge unit that discharges a treatment liquid in which carbon dioxide gas is dissolved in pure water toward the main surface of the substrate;
A processing liquid supply section for guiding the processing liquid to the discharge section;
Disposed in the vicinity of or at the position of the discharge port of the discharge unit while being electrically insulated from the discharge unit, a potential difference is applied between the discharge unit or the conductive liquid contact part of the processing liquid supply unit. An induction electrode that induces an electric charge in the treatment liquid in the vicinity of the discharge port,
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The substrate processing apparatus is characterized in that the specific resistance of the treatment liquid is 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less. A substrate processing apparatus for processing a substrate by supplying a processing liquid to the substrate,
A discharge unit that discharges a treatment liquid having a specific resistance of 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less toward the main surface of the substrate;
A processing liquid supply section for guiding the processing liquid to the discharge section;
Disposed in the vicinity of or at the position of the discharge port of the discharge unit while being electrically insulated from the discharge unit, a potential difference is applied between the discharge unit or the conductive liquid contact part of the processing liquid supply unit. An induction electrode that induces an electric charge in the treatment liquid in the vicinity of the discharge port,
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 3, wherein
The substrate processing apparatus is characterized in that the specific resistance of the treatment liquid is 5 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less. The substrate processing apparatus according to claim 3 or 4, wherein
The substrate processing apparatus, wherein the processing liquid is a liquid obtained by dissolving a gas in pure water. A substrate processing apparatus according to any one of claims 1 to 5,
The substrate processing apparatus, wherein the discharge unit ejects droplets of the processing liquid toward the substrate. The substrate processing apparatus according to claim 6,
The substrate processing apparatus, wherein the discharge unit generates the droplets of the processing liquid by mixing the processing liquid and a carrier gas in the discharge unit or in the vicinity of the discharge port. A substrate processing method for processing a substrate by supplying a processing liquid to the substrate,
a) discharging a treatment liquid obtained by dissolving carbon dioxide gas in pure water from a discharge unit connected to the treatment liquid supply unit toward the main surface of the substrate;
b) Inductive electrodes arranged in the vicinity of or at the position of the discharge port of the discharge unit while being electrically insulated from the discharge unit, and a conductive liquid contact portion of the discharge unit or the processing liquid supply unit Inducing a charge in the treatment liquid in the vicinity of the discharge port in parallel with the step a) by applying a potential difference between
A substrate processing method comprising: A substrate processing method for processing a substrate by supplying a processing liquid to the substrate,
a) discharging a treatment liquid having a specific resistance of 1 × 10 ² Ωm or more and 4 × 10 ³ Ωm or less from a discharge part connected to the treatment liquid supply part toward the main surface of the substrate;
b) Inductive electrodes arranged in the vicinity of or at the position of the discharge port of the discharge unit while being electrically insulated from the discharge unit, and a conductive liquid contact portion of the discharge unit or the processing liquid supply unit Inducing a charge in the treatment liquid in the vicinity of the discharge port in parallel with the step a) by applying a potential difference between
A substrate processing method comprising:

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