JP2013077626A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damages of a substrate due to movement of electric charges during processing by a process liquid, and to prevent adverse influence by mixing of the process liquid and another liquid.SOLUTION: In a substrate processing apparatus 1, an electricity removal liquid whose specific resistance is larger than that of an SPM liquid is supplied onto a substrate 9 by an electricity removal liquid supply part 6, the entire upper surface 91 of the substrate 9 is paddled with the electricity removal liquid, and thus the electricity of the substrate 9 is relatively gently removed. Then, by rotating the substrate 9 by a substrate rotating mechanism 5, the electricity removal liquid is removed from the substrate 9, then the SPM liquid is supplied onto the substrate 9 by a process liquid supply part 3, and SPM processing is performed. Thus, during the SPM processing, rapid movement of a large amount of electric charges from the substrate 9 to the SPM liquid is prevented, and the damages of the substrate 9 are prevented. Also, the adverse influence by mixing of the electricity removal liquid and the SPM liquid (for instance, the damages of the substrate 9 due to reaction heat between water in the electricity removal liquid and sulfuric acid in the SPM liquid) is prevented.

Description

  The present invention relates to a technique for processing a substrate.

  Conventionally, in a manufacturing process of a semiconductor substrate (hereinafter simply referred to as “substrate”), various processes are performed on a substrate having an insulating film such as an oxide film using a substrate processing apparatus. For example, by supplying a chemical solution to a substrate having a resist pattern formed on the surface, a process such as etching is performed on the surface of the substrate. In addition, after the etching or the like is finished, a process for removing the resist on the substrate is also performed.

  In the substrate processing apparatus of Patent Document 1, before processing with a chemical solution such as an SPM (sulfuric acid / hydrogen peroxide mixture) solution, a liquid having a lower electrical conductivity than the chemical solution is supplied to the processing region on the substrate, and the liquid By discharging the chemical solution to the processing region in a state where the substrate exists on the processing region, local damage to the substrate caused by contact between the substrate and the chemical solution is prevented. The local damage of the substrate is the destruction of the field oxide film or the gate oxide film in the processing region, and the destruction is the treatment of the substrate in a state where the chemical solution is charged by the frictional charging phenomenon between the chemical solution and the chemical solution nozzle. Caused by touching an area.

JP 2009-200365 A

  By the way, in the substrate processing apparatus of patent document 1, for example, when water is contained in the liquid supplied onto the substrate before the chemical processing, sulfuric acid and water in the SPM liquid, which is a chemical, are used during the chemical processing. And the reaction heat may cause damage to the substrate. In addition, the chemical solution supplied to the substrate is diluted with the liquid supplied in advance, so that the quality of the process is reduced, or the concentration of the chemical solution becomes non-uniform due to partial mixing with the liquid. There is also a possibility that the uniformity is lowered.

  On the other hand, the substrate processed by the substrate processing apparatus is subjected to a dry process such as dry etching or plasma CVD (Chemical Vapor Deposition) before being carried into the substrate processing apparatus. In such a dry process, since charges are generated in the device and charged, the substrate is carried into the substrate processing apparatus in a charged state (so-called carry-in charging). In the substrate processing apparatus, when a chemical solution having a small specific resistance such as an SPM solution is supplied onto the substrate, the electric charge in the device rapidly moves from the device to the chemical solution (that is, discharges into the chemical solution). ), The device may be damaged by the heat generated by the movement. In view of this, it is conceivable to neutralize the substrate with an ionizer before supplying the chemical solution to the substrate. However, it is difficult to efficiently eliminate the charge when the charge amount of the substrate is large.

  The present invention has been made in view of the above problems, and it is an object of the present invention to prevent damage to a substrate due to movement of electric charges during processing with a processing liquid and to prevent adverse effects due to mixing of the processing liquid with other liquids. It is said.

  The invention according to claim 1 is a substrate processing apparatus for processing a substrate, wherein a substrate holding unit that holds the substrate with the main surface facing upward, and a processing liquid is supplied onto the main surface of the substrate A treatment liquid supply unit that performs a neutralization liquid supply unit that supplies a neutralization liquid having a specific resistance larger than that of the treatment liquid onto the main surface of the substrate, and a liquid removal unit that removes the liquid on the main surface of the substrate. And controlling the treatment liquid supply unit, the neutralization liquid supply unit, and the liquid removal unit to supply the neutralization liquid onto the main surface of the substrate so that the entire main surface of the substrate is the neutralization liquid. And a controller that removes the static elimination liquid from the main surface and supplies the processing liquid onto the main surface of the substrate to perform a predetermined process.

  Invention of Claim 2 is the substrate processing apparatus of Claim 1, Comprising: The said liquid removal part passes the center of the said board | substrate, and it is centered on the rotating shaft perpendicular | vertical to the said main surface of the said board | substrate. A substrate rotation mechanism that removes the liquid on the main surface by rotating the substrate together with the substrate holding unit is provided.

  According to a third aspect of the present invention, in the substrate processing apparatus according to the second aspect of the present invention, the entire main surface of the substrate is paddle-processed by the neutralizing liquid while the substrate rotation mechanism is stopped.

  A fourth aspect of the present invention is the substrate processing apparatus according to any one of the first to third aspects, wherein the liquid removing unit supplies liquid isopropyl alcohol onto the main surface of the substrate. And an IPA supply section for extruding and removing the liquid on the main surface from the edge of the substrate.

  Invention of Claim 5 is the substrate processing apparatus in any one of Claim 1 thru | or 4, Comprising: The said process liquid is a SPM liquid which mixed the heated sulfuric acid and hydrogen peroxide water, The predetermined process is an SPM process.

  Invention of Claim 6 is a substrate processing apparatus in any one of Claim 1 thru | or 5, Comprising: The specific resistance setting part which sets the target specific resistance of the said static elimination liquid is further provided, The said static elimination liquid, It is a liquid containing ions or pure water, and is controlled by the control unit to control the ion concentration in the static elimination liquid to maintain the specific resistance of the static elimination liquid at the target specific resistance, while maintaining the target specific resistance of the substrate by the static elimination liquid. The entire main surface is subjected to paddle processing.

  A seventh aspect of the present invention is the substrate processing apparatus according to the sixth aspect, wherein the specific resistance setting unit has a larger target specific resistance as a size of a device formed in advance on the substrate is smaller. Is set.

  The invention according to claim 8 is the substrate processing apparatus according to claim 6 or 7, wherein the liquid containing ions dissolves carbon dioxide in pure water.

  The invention according to claim 9 is a substrate processing method for processing a substrate, wherein a) a charge removing liquid is supplied onto the main surface of the substrate held with the main surface facing upward. Padding the entire main surface with the neutralization solution, b) removing the neutralization solution from the main surface after the step a), c) after the step b), Supplying a treatment liquid having a specific resistance smaller than that of the charge removal liquid onto the main surface of the substrate to perform a predetermined treatment.

  In the present invention, it is possible to prevent the substrate from being damaged due to the movement of electric charges during the treatment with the treatment liquid, and to prevent adverse effects due to the mixing of the treatment liquid and other liquids.

It is a figure which shows the structure of the substrate processing apparatus which concerns on 1st Embodiment. It is a figure which shows the flow of a process of a board | substrate. It is a figure which shows surface potential distribution on the board | substrate before and behind static elimination processing. It is a figure which shows surface potential distribution on the board | substrate before and behind static elimination processing. It is a figure which shows surface potential distribution on the board | substrate before and behind static elimination processing. It is a figure which shows surface potential distribution on the board | substrate before and behind static elimination processing. It is a figure which shows the structure of the substrate processing apparatus which concerns on 2nd Embodiment. It is a figure which shows a part of flow of a process of a board | substrate.

  FIG. 1 is a diagram showing a configuration of a substrate processing apparatus 1 according to a first embodiment of the present invention. As shown in FIG. 1, the substrate processing apparatus 1 is a single-wafer type apparatus that processes semiconductor substrates 9 (hereinafter simply referred to as “substrates 9”) one by one. In the substrate processing apparatus 1, an SPM (sulfuric acid / hydrogen peroxide mixture) solution is supplied to the substrate 9 to perform an SPM process, that is, a resist film removal process on the substrate 9.

  The substrate processing apparatus 1 includes a substrate holding unit 2 that holds the substrate 9 with one main surface 91 (hereinafter referred to as “upper surface 91”) of the substrate 9 facing upward, and an SPM toward the upper surface 91 of the substrate 9. A processing liquid supply unit 3 for discharging a liquid such as a liquid, a cup unit 4 surrounding the substrate 9 and the substrate holding unit 2, a substrate rotating mechanism 5 for horizontally rotating the substrate 9 together with the substrate holding unit 2, and an upper surface 91 of the substrate 9 A neutralization liquid supply unit 6 for supplying a neutralization liquid, a specific resistance setting unit 81 for setting a target specific resistance of the neutralization liquid, and a control unit 8 for controlling these mechanisms are provided. The substrate 9 is rotated by the substrate rotating mechanism 5 together with the substrate holding unit 2 about a rotation axis that passes through the center of the substrate 9 and is perpendicular to the upper surface 91 of the substrate 9. Further, the specific resistance setting unit 81 is connected to the control unit 8. In the substrate processing apparatus 1, the substrate holding unit 2, the cup unit 4, the substrate rotating mechanism 5 and the like are accommodated in a chamber (not shown).

  The treatment liquid supply unit 3 generates a mixed liquid connected to the sulfuric acid supply unit 31 that supplies sulfuric acid, the hydrogen peroxide solution supply unit 32 that supplies hydrogen peroxide solution, the sulfuric acid supply unit 31, and the hydrogen peroxide solution supply unit 32. A processing liquid nozzle 34 that is disposed above the substrate 33 and that discharges liquid toward the substrate 9; and a processing liquid nozzle rotating mechanism 35 that rotates the processing liquid nozzle 34 horizontally around the rotation axis 351. Is provided. The processing liquid nozzle rotation mechanism 35 includes an arm 352 that extends in the horizontal direction from the rotation shaft 351 and to which the processing liquid nozzle 34 is attached.

  The sulfuric acid supply unit 31 is connected to the sulfuric acid storage unit 311 for storing sulfuric acid, the sulfuric acid storage unit 311 and the mixed liquid generation unit 33, and the sulfuric acid storage unit 311 to the mixed liquid generation unit 33 via the sulfuric acid piping 312. And a sulfuric acid pump 313 for supplying sulfuric acid, a sulfuric acid valve 314 provided on the sulfuric acid pipe 312, and a sulfuric acid heating unit 315 provided on the sulfuric acid pipe 312 between the sulfuric acid pump 313 and the sulfuric acid valve 314 for heating sulfuric acid. Prepare. The sulfuric acid pipe 312 branches between the sulfuric acid heating unit 315 and the sulfuric acid valve 314 and is connected to the sulfuric acid storage unit 311. When the sulfuric acid valve 314 is closed, the sulfuric acid heated by the sulfuric acid heating unit 315 is connected. Circulates between the sulfuric acid storage part 311 and the sulfuric acid heating part 315.

  The hydrogen peroxide solution supply unit 32 includes a hydrogen peroxide solution storage unit 321 for storing hydrogen peroxide solution, a hydrogen peroxide solution storage unit 321, and a hydrogen peroxide solution pipe 322 connected to the mixed solution generation unit 33. A hydrogen peroxide solution pump 323 for supplying hydrogen peroxide solution from the hydrogen water storage unit 321 to the mixed solution generating unit 33 through the hydrogen peroxide solution pipe 322, and a peroxide provided on the hydrogen peroxide solution tube 322 A hydrogen water valve 324 is provided. The sulfuric acid storage unit 311 and the hydrogen peroxide solution storage unit 321 may be provided outside the substrate processing apparatus 1, and the sulfuric acid supply unit 31 and the hydrogen peroxide solution supply unit 32 may be connected to each other.

  The mixed liquid generation unit 33 is provided on the mixing valve 331 to which the sulfuric acid pipe 312 and the hydrogen peroxide pipe 322 are connected, the discharge pipe 332 connected to the mixing valve 331 and the processing liquid nozzle 34, and the discharge pipe 332. A stirring flow pipe 333 is provided. In the mixed solution generation unit 33, the heated sulfuric acid from the sulfuric acid supply unit 31 and the hydrogen peroxide solution at room temperature (that is, a temperature similar to room temperature) from the hydrogen peroxide solution supply unit 32 are mixed with each other. Is mixed to produce an SPM liquid (sulfuric acid / hydrogen peroxide) as a mixed liquid. The SPM liquid passes through the stirring flow pipe 333 and the discharge pipe 332 and is sent to the processing liquid nozzle 34. In the stirring flow pipe 333, the chemical reaction between sulfuric acid and hydrogen peroxide solution is promoted by stirring the SPM liquid. The SPM liquid that is the processing liquid is discharged from the discharge port at the tip of the processing liquid nozzle 34 toward the upper surface 91 of the substrate 9. In the present embodiment, sulfuric acid heated to about 130 ° C. to 150 ° C. by the sulfuric acid heating unit 315 is supplied from the sulfuric acid supply unit 31 to the mixed liquid generation unit 33. Note that the temperature of the sulfuric acid supplied from the sulfuric acid supply unit 31 may be changed as appropriate.

The neutralization liquid supply unit 6 supplies a liquid containing ions or pure water (DIW: deionized water) onto the upper surface 91 of the substrate 9 as a neutralization liquid having a higher specific resistance than the SPM liquid that is the treatment liquid. In the present embodiment, a liquid in which carbon dioxide (CO ₂ ) is dissolved in pure water is used as the liquid containing ions. The neutralization liquid supply unit 6 is provided on a pure water pipe 61 connected to a pure water supply unit (not shown), a carbon dioxide dissolution unit 62 connected to the pure water pipe 61, and a flow rate of pure water provided on the pure water pipe 61. A flow meter 63 for measuring the charge, a charge removal liquid pipe 64 connected to the carbon dioxide dissolution unit 62, a charge removal liquid nozzle 65 provided at the tip of the charge removal liquid pipe 64, a charge removal liquid valve 66 provided on the charge removal liquid pipe 64, a charge removal liquid A resistivity meter 67 provided on the charge removal liquid pipe 64 between the valve 66 and the charge removal liquid nozzle 65, and a charge removal liquid nozzle turning mechanism 68 for turning the charge removal liquid nozzle 65 horizontally around the rotation axis 681. Is provided. The neutralization liquid nozzle rotating mechanism 68 includes an arm 682 that extends in the horizontal direction from the rotation shaft 681 and to which the neutralization liquid nozzle 65 is attached.

  The discharge outlet at the tip of the static elimination liquid nozzle 65 is located above the center of the upper surface 91 of the substrate 9. The specific resistance meter 67 measures the specific resistance of the static elimination liquid flowing through the static elimination liquid pipe 64. The output from the resistivity meter 67 is sent to the control unit 8. Further, the target specific resistance of the neutralizing liquid set by the specific resistance setting unit 81, that is, a preferable specific resistance of the neutralizing liquid in the neutralizing process described later is sent to the control unit 8 and stored in advance. The specific resistance setting unit 81 stores a table indicating the relationship between the size of a device formed in advance on the substrate 9 and the target specific resistance of the charge eliminating liquid. The specific resistance setting unit 81 inputs the size of the device. Then, the target specific resistance is set based on the size and the table. In the specific resistance setting unit 81, a larger target specific resistance is set as the size of a device formed in advance on the substrate 9 is smaller (that is, as the minimum width of the device wiring is smaller). In the present embodiment, the target specific resistance is set in the range of 0.05 to 18 MΩ · cm. When the target specific resistance is 18 MΩ · cm, the carbon dioxide dissolution unit 62 does not dissolve carbon dioxide in the pure water from the pure water pipe 61, and the pure water serves as a charge removal liquid from the charge removal liquid nozzle 65 to the substrate 9. To be supplied.

  In the substrate processing apparatus 1, the controller 8 supplies the neutralization liquid based on the output from the specific resistance meter 67 (that is, the measured value of the specific resistance of the neutralization liquid in the neutralization liquid pipe 64) and the above-described target specific resistance. The amount of carbon dioxide dissolved in the pure water from the pure water pipe 61 is controlled by feedback control of the carbon dioxide dissolution unit 62 of the unit 6. In other words, the ion concentration in the static elimination liquid sent from the carbon dioxide dissolution unit 62 to the static elimination liquid piping 64 is controlled. Thereby, the specific resistance of the static elimination liquid is maintained at the target specific resistance. Specifically, by the feedback control, the specific resistance of the static elimination liquid is maintained within a narrow specific resistance range (of course, including the target specific resistance) that can be said to be substantially equal to the target specific resistance.

  FIG. 2 is a diagram illustrating a processing flow of the substrate 9 in the substrate processing apparatus 1. In the substrate processing apparatus 1, first, the substrate 9 is loaded and held by the substrate holding unit 2. The substrate 9 is subjected to a dry process such as dry etching or plasma CVD (Chemical Vapor Deposition) before being carried into the substrate processing apparatus 1, and the substrate 9 is in a charged state.

  Subsequently, based on the size of the device on the substrate 9 input in advance, the target specific resistance of the static elimination liquid is set by the specific resistance setting unit 81 and stored in the control unit 8 (step S11). In the neutralization liquid supply unit 6, the neutralization liquid valve 66 is opened by the control unit 8 in a state where the neutralization liquid nozzle 65 is positioned at the standby position outside the substrate 9, and discharge of the neutralization liquid from the neutralization liquid nozzle 65 is started. The Then, feedback control is performed based on the output from the specific resistance meter 67 and the target specific resistance, the ion concentration of the static elimination liquid is controlled, and the specific resistance of the static elimination liquid is set as the target specific resistance (step S12).

  Next, the neutralization liquid nozzle 65 is moved from the standby position by the neutralization liquid nozzle rotating mechanism 68, and the discharge port at the tip of the neutralization liquid nozzle 65 faces the center of the upper surface 91 of the substrate 9 as shown in FIG. . At this time, the substrate rotating mechanism 5 is stopped or controlled by the control unit 8 so as to rotate at a small rotational speed, and the substrate 9 is not rotated or is at a small rotational speed (for example, 10 to 200 rpm). It is in the state of rotating at. Then, after a predetermined amount of the neutralizing liquid is supplied from the neutralizing liquid nozzle 65 onto the upper surface 91 of the substrate 9, the supply of the neutralizing liquid from the neutralizing liquid nozzle 65 is stopped (so-called liquid accumulation is performed). . The neutralizing liquid supplied from the neutralizing liquid nozzle 65 spreads from the center of the substrate 9 to the entire upper surface 91, and a thin layer (for example, a layer having a thickness of about 1 mm) of the neutralizing liquid is formed on the upper surface 91, so Is padded with a charge-removing solution. As a result, the charge on the substrate 9 moves relatively slowly to the charge removal solution, and the charge removal process (that is, the paddle process using the charge removal solution) is performed on the entire upper surface 91 of the substrate 9 (step S13). This paddle treatment with the charge-removing solution is a predetermined state in which the entire upper surface 91 of the substrate 9 is paddled with the charge-removing solution while the substrate rotation mechanism 5 is stopped or rotated at a low rotation speed (for example, 10 to 200 rpm). This is done by maintaining only time.

  FIG. A and FIG. B is a diagram showing the surface potential distribution of the substrate 9 before and after the charge removal process. FIG. A shows the surface potential distribution on one diameter of the substrate 9, FIG. B is shown in FIG. The surface potential distribution on one diameter orthogonal to the diameter corresponding to A is shown. FIG. A and FIG. The horizontal axis of B shows the position on the diameter of the substrate 9, and the vertical axis shows the potential at that position. A broken line 901 indicates the potential distribution before the charge removal process, and a solid line 902 indicates the potential distribution after the charge removal process. FIG. A and FIG. The above description regarding B is described later with reference to FIG. A and FIG. The same applies to B.

  FIG. A and FIG. B is a potential distribution of the substrate 9 when pure water is used as a charge removal solution because the size of the device on the substrate 9 is very small. FIG. A and FIG. As shown in B, the charge removal on the substrate 9 is reduced by the above-described charge removal process using pure water as a charge removal solution, and the potential of the substrate 9 is reduced as a whole.

FIG. A and FIG. B is a diagram showing the surface potential distribution of the substrate before and after the charge removal process on the substrate having a relatively large device size (that is, relatively high resistance to damage due to charge transfer). FIG. A and FIG. In the example shown in B, CO ₂ water in which carbon dioxide is dissolved in pure water so as to have the target specific resistance set by the specific resistance setting unit 81 is used as the static elimination liquid. FIG. A and FIG. As shown in B, the above-described charge removal process using CO ₂ water as a charge removal liquid reduces the charge on the substrate and reduces the overall potential of the substrate. By using CO ₂ water having a specific resistance smaller than that of pure water as the charge removal liquid, the time required for the charge removal process can be shortened.

  When the neutralization process of the substrate 9 is completed, the neutralization liquid nozzle 65 is returned to the standby position by the neutralization liquid nozzle rotating mechanism 68. Subsequently, the substrate rotating mechanism 5 is controlled by the control unit 8 to start the rotation of the substrate 9 (step S14). When the above-described charge removal process is performed in a state where the substrate 9 is rotating at a low rotation speed, the rotation speed of the substrate 9 is increased. Then, due to the rotation of the substrate 9, the static elimination liquid on the upper surface 91 of the substrate 9 moves toward the edge of the substrate 9, scatters from the edge of the substrate 9 to the outside, and is removed from the substrate 9 (step S <b> 15). . The neutralizing liquid scattered from the substrate 9 is received by the cup portion 4. In the substrate processing apparatus 1, the substrate rotation mechanism 5 functions as a liquid removal unit that removes the liquid on the upper surface 91 by rotating the substrate 9.

  When the removal of the charge removal liquid is completed, the number of rotations of the substrate 9 by the substrate rotation mechanism 5 is reduced and changed to the number of rotations during the SPM process. Also, the processing liquid nozzle rotating mechanism 35 starts to rotate the processing liquid nozzle 34, and the processing liquid nozzle 34 repeats reciprocating motion between the center portion and the edge of the substrate 9.

  Next, when the processing liquid supply unit 3 is controlled by the control unit 8, the sulfuric acid valve 314 of the sulfuric acid supply unit 31 is opened, and the sulfuric acid heated to about 130 ° C. to 150 ° C. by the sulfuric acid heating unit 315 is converted into sulfuric acid. The mixed liquid generation unit 33 is supplied via the pipe 312. Further, the control unit 8 opens the hydrogen peroxide solution valve 324, and normal temperature hydrogen peroxide solution is supplied from the hydrogen peroxide solution storage unit 321 to the mixing valve 331 via the hydrogen peroxide solution pipe 322. In the mixing valve 331, the heated sulfuric acid and the hydrogen peroxide solution at room temperature are mixed to generate the SPM liquid. The temperature of the SPM liquid is higher than the temperature of sulfuric acid supplied from the sulfuric acid supply unit 31 due to the reaction between sulfuric acid and hydrogen peroxide solution, and is about 150 ° C. to 195 ° C., for example.

  The SPM liquid passes through the discharge pipe 332 and the stirring flow pipe 333 and is supplied from the processing liquid nozzle 34 to the upper surface 91 of the substrate 9. In other words, heated sulfuric acid and hydrogen peroxide solution are mixed and supplied to the upper surface 91 of the substrate 9 by the processing liquid supply unit 3. The SPM liquid spreads over the entire upper surface 91 of the substrate 9 by the rotation of the substrate 9, scatters from the edge of the substrate 9 to the outside, and is received by the cup portion 4. In the substrate processing apparatus 1, the supply of the SPM liquid to the substrate 9 is continuously performed for a predetermined time, and the SPM process for the substrate 9, that is, the resist film on the substrate 9 due to the strong oxidizing power of caloic acid contained in the SPM liquid. A removal process is performed (step S16). In the substrate processing apparatus 1, the SPM liquid or the like may be supplied from the processing liquid nozzle 34 stopped above the center of the substrate 9.

  When the SPM treatment is completed, the sulfuric acid valve 314 is closed with the hydrogen peroxide solution valve 324 opened, and the hydrogen peroxide solution passes through the mixing valve 331, the discharge pipe 332, and the stirring flow pipe 333, and the treatment liquid From the nozzle 34, the resist film is supplied onto the substrate 9 (step S17). By the hydrogen peroxide supply process, the SPM liquid remaining in the mixing valve 331, the discharge pipe 332, the stirring flow pipe 333, and the processing liquid nozzle 34 is removed. Further, the hydrogen peroxide solution supplied onto the substrate 9 spreads over the entire upper surface 91 of the substrate 9 by the rotation of the substrate 9, and the SPM liquid remaining on the substrate 9 is moved outward from the edge of the substrate 9. Extrude and remove.

  When the hydrogen peroxide solution supply process is completed, the hydrogen peroxide solution valve 324 is closed and the supply of the hydrogen peroxide solution is stopped, and the treatment solution nozzle 34 is placed on standby outside the substrate 9 by the treatment solution nozzle rotating mechanism 35. Moved to position. Next, a rinsing process in which a rinsing liquid is supplied to the upper surface 91 of the substrate 9 is performed (step S18). Pure water is used as the rinse liquid. The rinsing liquid may be supplied from a rinsing liquid supply unit (not shown) or may be supplied by the charge removal liquid supply unit 6. The rinse liquid spreads over the entire upper surface 91 of the substrate 9 by the rotation of the substrate 9. Thereby, the hydrogen peroxide remaining on the substrate 9 is washed away. When the rinsing process is continuously performed for a predetermined time, the supply of the rinsing liquid is stopped. Then, the rotational speed of the substrate 9 is increased, and a drying process is performed to remove the rinse liquid remaining on the substrate 9 by the rotation of the substrate 9 (step S19). Thereafter, the rotation of the substrate 9 is stopped (step S20), and the substrate 9 is unloaded from the substrate processing apparatus 1.

  As described above, the substrate processing apparatus 1 has a specific resistance higher than that of the SPM liquid before the SPM process using the SPM liquid is performed on the substrate 9 that has been charged by a pre-process such as dry etching or plasma CVD. The neutralizing liquid is supplied, and the entire upper surface 91 of the substrate 9 is paddled by the neutralizing liquid. As a result, the entire upper surface 91 of the substrate 9 is discharged relatively slowly. At the time of static elimination, the charges on the substrate 9 do not suddenly move to the static elimination liquid and do not generate heat, so that damage to the device on the substrate 9 is prevented.

  Then, by supplying the SPM liquid to the substrate 9 after the charge removal process, even if the substrate 9 comes into contact with the SPM liquid having a specific resistance smaller than that of the charge removal liquid, a large amount from the substrate 9 to the SPM liquid is obtained. Therefore, even during the SPM treatment with the SPM liquid, it is possible to prevent device damage due to charge transfer, that is, damage to the substrate 9. Further, by controlling the neutralization liquid supply unit 6 so as to maintain the specific resistance of the neutralization liquid at the target specific resistance, the neutralization efficiency of the substrate 9 is improved and required for the neutralization process within a range where the substrate 9 is not damaged. Time can be shortened.

  In the substrate processing apparatus 1, the specific resistance setting unit 81 sets a larger target specific resistance as the device size on the substrate 9 is smaller, thereby preventing damage to the substrate 9 during the SPM process and the time required for the charge removal process. It is possible to appropriately balance the reduction of the size according to the size of the device. In addition, by controlling the amount of carbon dioxide dissolved in pure water in the carbon dioxide dissolution unit 62, it is possible to easily realize the control of the specific resistance of the static elimination liquid.

  As described above, in the substrate processing apparatus 1, the charge removal process using the charge removal liquid is performed, and after the charge removal liquid is removed from the upper surface 91 of the substrate 9, the SPM liquid is supplied to the substrate 9 and the SPM process is performed. Thereby, the bad influence by mixing with a static elimination liquid and a SPM liquid can be prevented. The adverse effects include, for example, damage to the substrate 9 due to reaction heat between water in the static elimination liquid and sulfuric acid in the SPM liquid (so-called heat shock), and the quality of the SPM treatment due to dilution of the SPM liquid by the static elimination liquid. It can be mentioned that the concentration of the SPM liquid becomes non-uniform due to the lowering and the partial mixing of the SPM liquid with the charge eliminating liquid, and the uniformity of the SPM process in the entire substrate 9 is reduced.

  In the substrate processing apparatus 1, the neutralizing solution on the substrate 9 can be easily removed by rotating the substrate 9 by the substrate rotating mechanism 5. Further, the substrate rotating mechanism 5 used for rotating the substrate 9 during the SPM process can remove the charge removal liquid from the substrate 9 in step S15, thereby simplifying the configuration of the substrate processing apparatus 1. be able to. Furthermore, by performing the charge removal process on the substrate 9 in a state where the substrate rotation mechanism 5 is stopped or rotating at a low rotation speed, the charge removal of the substrate 9 can be performed efficiently. The state in which the substrate rotation mechanism 5 is rotating at a small number of rotations means, for example, that the substrate 9 is rotated at 10 to 200 rpm by the substrate rotation mechanism 5, and the rotation causes This means a state where no substantial effect has occurred.

  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 a substrate processing apparatus 1a according to the second embodiment. In addition to the configuration of the substrate processing apparatus 1 shown in FIG. 1, the substrate processing apparatus 1 a includes an IPA supply unit 7 that supplies liquid isopropyl alcohol (hereinafter referred to as “IPA”) onto the upper surface 91 of the substrate 9. Other configurations are the same as those of the substrate processing apparatus 1 shown in FIG. 1, and the same reference numerals are given to the corresponding configurations in the following description. In FIG. 5, the processing liquid supply unit 3 is not shown for the sake of illustration, but the configuration of the processing liquid supply unit 3 is the same as that of the substrate processing apparatus 1 shown in FIG. In FIG. 5, illustration of the control unit 8 and the specific resistance setting unit 81 is also omitted.

  The IPA supply unit 7 includes an IPA pipe 71 connected to an IPA storage unit (not shown), an IPA nozzle 72 connected to the tip of the IPA pipe 71, an IPA valve 73 provided on the IPA pipe 71, and an IPA nozzle 72. An IPA nozzle rotation mechanism 74 that rotates horizontally around the rotation shaft 741 is provided. The IPA nozzle rotation mechanism 74 includes an arm 742 that extends in the horizontal direction from the rotation shaft 741 and to which the IPA nozzle 72 is attached.

  FIG. 6 is a diagram showing a part of the processing flow of the substrate 9 in the substrate processing apparatus 1a. In the substrate processing apparatus 1a, after steps similar to steps S11 to S13 shown in FIG. 2 are performed, steps S31 to S33 in FIG. 6 are performed, and thereafter steps similar to steps S16 to S20 shown in FIG. Is done.

  Specifically, first, in the specific resistance setting unit 81 (see FIG. 1), the target specific resistance of the static elimination liquid is set based on the size of the device on the substrate 9 and stored in the control unit 8 (step S11). ). In the neutralization liquid supply unit 6, the ion concentration of the neutralization liquid is controlled based on the output from the specific resistance meter 67 and the target specific resistance, and the specific resistance of the neutralization liquid is set as the target specific resistance (step S12). Then, the neutralizing liquid is supplied onto the substrate 9, and the entire upper surface 91 of the substrate 9 is padded with the neutralizing liquid, and the neutralizing process is performed (step S13).

  When the neutralization process of the substrate 9 is completed, the neutralization liquid nozzle 65 is rotated by the neutralization liquid nozzle rotation mechanism 68 and returned from the position shown in FIG. 5 to the standby position outside the substrate 9. Further, the IPA nozzle 72 is moved from the standby position by the IPA nozzle rotating mechanism 74, and the discharge port at the tip of the IPA nozzle 72 faces the center of the upper surface 91 of the substrate 9 as shown in FIG. 5. Subsequently, the control unit 8 opens the IPA valve 73 of the IPA supply unit 7 so that IPA is supplied onto the substrate 9. On the substrate 9, due to the IPA supplied to the central portion of the upper surface 91, the static elimination liquid moves toward the edge of the substrate 9 and is pushed out of the substrate 9 from the edge and removed from the upper surface 91 of the substrate 9. (Step S31). As described above, the IPA supply unit 7 functions as a liquid removing unit that removes the liquid such as the charge removing liquid on the substrate 9 from the upper surface 91 of the substrate 9 by replacing the liquid with the IPA.

  When the removal of the charge removal liquid is completed, the IPA nozzle 72 is returned to the standby position, and the substrate rotating mechanism 5 is controlled by the control unit 8, whereby the rotation of the substrate 9 is started (step S32). Then, due to the rotation of the substrate 9, the IPA on the upper surface 91 of the substrate 9 moves toward the edge of the substrate 9, scatters outward from the edge of the substrate 9, and is removed from the substrate 9 (step S33).

  When the removal of the IPA is completed, the number of rotations of the substrate 9 by the substrate rotation mechanism 5 is reduced and is changed to the number of rotations during the SPM process. Further, the processing liquid nozzle 34 starts rotating by the processing liquid nozzle rotating mechanism 35 shown in FIG. 1, and the processing liquid nozzle 34 repeats reciprocating motion between the center portion and the edge of the substrate 9. Then, the SPM liquid is supplied from the processing liquid nozzle 34 onto the upper surface 91 of the substrate 9, and the SPM process is performed on the substrate 9 (step S16). The supply of the SPM liquid to the substrate 9 may be started in a state where IPA remains on the substrate 9.

  When the SPM process is completed, hydrogen peroxide is supplied from the process liquid nozzle 34 onto the substrate 9, and the SPM liquid on the substrate 9 is removed (step S17). When the hydrogen peroxide solution supply process is completed, the process liquid nozzle 34 is returned to the standby position outside the substrate 9, and a rinse process is performed in which the rinse liquid (pure water) is supplied to the upper surface 91 of the substrate 9. Then, the hydrogen peroxide solution is removed from the substrate 9 (step S18). Then, the rotational speed of the substrate 9 is increased, and a drying process is performed to remove the rinse liquid remaining on the substrate 9 by the rotation of the substrate 9 (step S19). Thereafter, the rotation of the substrate 9 is stopped (step S20), and the substrate 9 is unloaded from the substrate processing apparatus 1a.

  In the substrate processing apparatus 1a, similarly to the substrate processing apparatus 1 shown in FIG. 1, before the SPM treatment with the SPM liquid is performed on the substrate 9 charged by the pretreatment such as dry etching or plasma CVD, the SPM liquid is used. In addition, the neutralization liquid having a large specific resistance is supplied, and the entire upper surface 91 of the substrate 9 is padded with the neutralization liquid. As a result, the entire upper surface 91 of the substrate 9 is discharged relatively slowly. Then, by performing the SPM process on the substrate 9 after the charge removal process, it is possible to prevent device damage due to charge transfer, that is, damage to the substrate 9. Further, by controlling the neutralization liquid supply unit 6 so as to maintain the specific resistance of the neutralization liquid at the target specific resistance, the neutralization efficiency of the substrate 9 is improved and required for the neutralization process within a range where the substrate 9 is not damaged. Time can be shortened.

  In the substrate processing apparatus 1a, after the static elimination liquid used for the static elimination process is removed from the upper surface 91 of the substrate 9, the SPM liquid is supplied to the substrate 9 to perform the SPM process. Thereby, the above-mentioned bad influence like the heat shock by mixing with a static elimination liquid and a SPM liquid can be prevented. Further, by supplying IPA onto the substrate 9 in step S31, the charge removal liquid can be removed without rotating the substrate 9. By the way, when it is going to remove the static elimination liquid by rotating the board | substrate 9, when the width | variety of the wiring pattern of the device on the board | substrate 9 is small, a wiring pattern may collapse by the surface tension of a static elimination liquid. In the substrate processing apparatus 1a, as described above, since the static eliminating liquid is removed from the substrate 9 by the IPA having a surface tension smaller than that of pure water or the like, the IPA is removed by the rotation of the substrate 9, so that the static eliminating liquid is removed. It is possible to prevent substrate damage such as collapse of the wiring pattern at the time.

  Since the substrate processing apparatus 1a includes the substrate rotation mechanism 5 and the IPA supply unit 7, one of the substrate rotation mechanism 5 and the IPA supply unit 7 is selected according to the size of the device on the substrate 9 and the like. You may utilize as a liquid removal part. That is, in the substrate processing apparatus 1a, the liquid removal unit includes the substrate rotation mechanism 5 and the IPA supply unit 7.

  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.

  For example, the neutralization process in step S13 may be performed while the substrate 9 is rotating as long as the layer of the neutralization solution on the substrate 9 is maintained without collapsing. In other words, the rotation of the substrate 9 may be started before the charge removal process. In addition, the target specific resistance of the static elimination liquid may be set based on conditions other than the size of the device (for example, the type of processing performed on the substrate before being loaded into the substrate processing apparatus).

  In the substrate processing apparatuses 1 and 1a, an air knife that ejects sheet-like air toward the upper surface 91 of the substrate 9 and scatters and removes the liquid on the substrate 9 may be provided as a liquid removal unit.

  In the substrate processing apparatuses 1 and 1a, in step S16, a processing liquid other than the SPM liquid may be supplied onto the substrate 9, and other processing may be performed on the substrate 9. For example, the substrate 9 may be etched by supplying buffered hydrofluoric acid (BHF) as a treatment liquid onto the substrate 9 on which the resist film is formed. In the substrate processing apparatuses 1 and 1a, as described above, since the substrate 9 can be prevented from being damaged due to a rapid movement of charges due to contact between the charged substrate 9 and the processing liquid, the structure of the substrate processing apparatus 1 is as follows. In particular, the present invention is particularly suitable for an apparatus that performs treatment with a treatment liquid having a very small specific resistance, such as SPM liquid or buffered hydrofluoric acid.

  The liquid containing ions used as a static elimination liquid is not limited to a liquid in which carbon dioxide is dissolved in pure water. For example, a solution obtained by dissolving ammonia in pure water or a solution obtained by adding a small amount of dilute hydrochloric acid to pure water may be used as a static elimination liquid, or a liquid containing various other ions may be used as a static elimination liquid. Good. Furthermore, the neutralization liquid is not limited to a liquid containing ions or pure water as long as the specific resistance is higher than that of the treatment liquid, and various types of liquids may be used as the neutralization liquid.

  In the substrate processing apparatuses 1 and 1 a, it is not always necessary to maintain the specific resistance of the static elimination liquid at the target specific resistance as long as the static elimination treatment is performed with the static elimination liquid having a specific resistance higher than that of the treatment liquid. In this case, the specific resistance setting unit 81 may be omitted.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1,1a Substrate processing apparatus 2 Substrate holding part 3 Processing liquid supply part 5 Substrate rotation mechanism 6 Static elimination liquid supply part 7 IPA supply part 8 Control part 9 Substrate 81 Resistivity setting part 91 Upper surface S11-S20, S31-S33 Step

Claims (9)

A substrate processing apparatus for processing a substrate,
A substrate holding part for holding the substrate with the main surface facing upward;
A treatment liquid supply unit for supplying a treatment liquid onto the main surface of the substrate;
A static elimination liquid supply unit for supplying a static elimination liquid having a specific resistance larger than that of the treatment liquid onto the main surface of the substrate;
A liquid removal unit for removing liquid on the main surface of the substrate;
By controlling the treatment liquid supply unit, the neutralization liquid supply unit, and the liquid removal unit, the neutralization liquid is supplied onto the main surface of the substrate, and the entire main surface of the substrate is used as the neutralization liquid. After the paddle, a controller that removes the static elimination liquid from the main surface, and further supplies the processing liquid onto the main surface of the substrate to perform a predetermined process;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The substrate that removes the liquid on the main surface by rotating the substrate together with the substrate holding unit about the rotation axis that passes through the center of the substrate and is perpendicular to the main surface of the substrate. A substrate processing apparatus comprising a rotation mechanism. The substrate processing apparatus according to claim 2,
The substrate processing apparatus, wherein a paddle process is performed on the entire main surface of the substrate by the charge eliminating liquid while the substrate rotating mechanism is stopped. A substrate processing apparatus according to any one of claims 1 to 3,
The liquid removing unit includes an IPA supply unit that pushes and removes the liquid on the main surface from the edge of the substrate by supplying liquid isopropyl alcohol onto the main surface of the substrate. A substrate processing apparatus. The substrate processing apparatus according to claim 1, wherein:
The substrate processing apparatus, wherein the processing liquid is an SPM liquid obtained by mixing heated sulfuric acid and hydrogen peroxide water, and the predetermined processing is SPM processing. A substrate processing apparatus according to any one of claims 1 to 5,
A specific resistance setting unit for setting a target specific resistance of the static elimination liquid;
The static elimination liquid is a liquid containing ions or pure water,
Under the control of the controller, the ion concentration in the static elimination liquid is controlled to maintain the specific resistance of the static elimination liquid at the target specific resistance, and the entire main surface of the substrate is padded with the static elimination liquid. A substrate processing apparatus. The substrate processing apparatus according to claim 6,
The substrate processing apparatus, wherein the specific resistance setting unit sets a larger target specific resistance as the size of a device formed in advance on the substrate is smaller. The substrate processing apparatus according to claim 6 or 7, wherein
The substrate processing apparatus, wherein the liquid containing ions is obtained by dissolving carbon dioxide in pure water. A substrate processing method for processing a substrate, comprising:
a) supplying a charge-removing solution onto the main surface of the substrate held with the main surface facing upward, and padding the entire main surface of the substrate with the charge-removing solution;
b) After the step a), the step of removing the static elimination liquid from the main surface;
c) after the step b), supplying a treatment liquid having a specific resistance smaller than that of the charge removal liquid onto the main surface of the substrate to perform a predetermined treatment;
A substrate processing method comprising:

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