JP4488780B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for performing processing using a processing liquid on a substrate.

  Processing to various substrates such as semiconductor wafers, flat panel display (FPD) substrates such as liquid crystal display substrates or plasma display substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photomask substrates, etc. A substrate processing apparatus that performs processing using a liquid is used.

  For example, in a development process for performing a development process on a photosensitive film such as a resist film formed on a substrate, a developer liquid film is supplied as a processing liquid onto the substrate, whereby a developer liquid film is formed on the upper surface of the substrate. The liquid film of the developer is formed on the substrate and held for a certain time. Thereby, development of the photosensitive film formed on the substrate proceeds.

  Further, in the resist stripping process for stripping the resist film formed on the substrate, a resist stripping liquid is formed on the top surface of the substrate by supplying the resist stripping liquid as a processing liquid on the substrate, The liquid film of the resist stripping solution is held for a certain time. Thereby, the resist film on the substrate is peeled off.

Furthermore, in the polymer removal cleaning process for removing polymers such as organometallic polymers, metal substances, and etching residues generated in the semiconductor device manufacturing stage, the cleaning liquid is supplied as a processing liquid on the substrate, thereby A liquid film of the cleaning liquid is formed on the upper surface, and the liquid film of the cleaning liquid is held on the substrate for a certain time (see, for example, Patent Document 1). Thereby, the polymer on the substrate is removed.
JP 2000-286180 A

  However, in the substrate processing apparatus using the processing liquid as described above, if the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate is uneven, the processing becomes non-uniform. Since the liquid film of the processing liquid formed on the upper surface of the substrate is as thin as 1 mm or less and is transparent, it is difficult to accurately measure the thickness of the liquid film of the processing liquid on the upper surface of the substrate. For this reason, it is not easy to uniformly control the thickness of the liquid film of the processing liquid formed on the substrate.

  An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of accurately measuring the thickness of a liquid film of a processing liquid formed on an upper surface of a substrate.

A substrate processing apparatus according to a first aspect of the present invention is a substrate processing apparatus that performs processing using a processing liquid on a substrate, the substrate holding means for holding the substrate substantially horizontally, and the substrate held by the substrate holding means. A processing liquid supply means for forming a liquid film of the processing liquid on the upper surface of the substrate by supplying the processing liquid; a distance measuring means for measuring a distance to the surface of the liquid film of the processing liquid formed on the upper surface of the substrate ; Control means for controlling the supply operation of the processing liquid by the processing liquid supply means based on the distance to the surface of the liquid film measured by the distance measuring means .

  In the substrate processing apparatus according to the present invention, the substrate is held substantially horizontally by the substrate holding means, and the processing liquid is supplied onto the substrate by the processing liquid supply means, whereby a liquid film of the processing liquid is formed on the upper surface of the substrate. The

Before forming the liquid film of the processing liquid, the distance to the upper surface of the substrate can be measured by the distance measuring means. Further, after the formation of the liquid film of the processing liquid, the distance to the surface of the liquid film can be measured by the distance measuring means. Accordingly, the thickness of the liquid film of the treatment liquid is determined based on the difference between the distance to the upper surface of the substrate before the formation of the liquid film of the treatment liquid and the distance to the surface of the liquid film after the formation of the liquid film of the treatment liquid. Can be calculated. Therefore, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately measured.
In addition, by controlling the supply operation of the processing liquid based on the distance to the surface of the liquid film measured by the distance measuring means, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate is accurately set to a predetermined value. Can be controlled.

  The distance measuring means may include an ultrasonic distance measuring sensor. In this case, the ultrasonic wave transmitted from the ultrasonic distance measuring sensor is reflected on the surface of the liquid film, and the reflected wave is received by the ultrasonic distance measuring sensor, thereby measuring the distance to the surface of the liquid film. Is done.

  Here, the ultrasonic waves are reflected on the surface of the object regardless of whether the object is transparent or opaque. Therefore, according to the ultrasonic distance measuring sensor, the distance to the upper surface of the substrate can be accurately measured before the liquid film of the processing liquid is formed. In addition, according to the ultrasonic distance measuring sensor, the distance to the surface of the liquid film can be accurately measured after the liquid film of the processing liquid is formed regardless of whether the liquid film is transparent or opaque. Accordingly, the thickness of the liquid film of the treatment liquid is determined based on the difference between the distance to the upper surface of the substrate before the formation of the liquid film of the treatment liquid and the distance to the surface of the liquid film after the formation of the liquid film of the treatment liquid. Can be calculated. Therefore, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately measured.

  The distance measuring means may include a laser type distance measuring sensor. In this case, the laser beam emitted from the laser type distance measuring sensor is reflected on the surface of the liquid film, and the reflected light is received by the laser type distance measuring sensor, whereby the distance to the surface of the liquid film is measured. .

  Here, the laser distance measuring sensor can measure the distance to the object with high resolution. Therefore, according to the laser type distance measuring sensor, the distance to the upper surface of the substrate can be accurately measured before the liquid film of the processing liquid is formed. Further, according to the laser type distance measuring sensor, the distance to the surface of the liquid film can be accurately measured after the liquid film of the processing liquid is formed. Accordingly, the thickness of the liquid film of the treatment liquid is determined based on the difference between the distance to the upper surface of the substrate before the formation of the liquid film of the treatment liquid and the distance to the surface of the liquid film after the formation of the liquid film of the treatment liquid. Can be calculated. Therefore, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately measured.

  The distance measuring means may include a microwave distance measuring sensor. In this case, the microwave transmitted from the microwave distance measuring sensor is reflected on the surface of the liquid film, and the reflected wave is received by the microwave distance measuring sensor, thereby measuring the distance to the surface of the liquid film. Is done.

  Here, the microwave is reflected on the surface of the object regardless of whether the object is transparent or opaque. Therefore, according to the microwave distance measuring sensor, the distance to the upper surface of the substrate can be accurately measured before the liquid film of the processing liquid is formed. Further, according to the microwave distance measuring sensor, the distance to the surface of the liquid film can be accurately measured after the liquid film of the processing liquid is formed regardless of whether the liquid film is transparent or opaque. Accordingly, the thickness of the liquid film of the treatment liquid is determined based on the difference between the distance to the upper surface of the substrate before the formation of the liquid film of the treatment liquid and the distance to the surface of the liquid film after the formation of the liquid film of the treatment liquid. Can be calculated. Therefore, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately measured.

  The substrate processing apparatus may further include a moving unit that moves the distance measuring unit relative to the substrate held by the substrate holding unit.

  In this case, by moving the distance measuring means relative to the substrate held by the substrate holding means by the moving means, the distance to the upper surface of the substrate at any position of the substrate and the liquid film at any position on the substrate It is possible to accurately measure the distance to the surface. Thereby, it is possible to accurately measure the thickness of the liquid film of the processing liquid at an arbitrary position on the substrate.

  Furthermore, if the distance to the surface of the liquid film is measured each time the distance measuring means and the substrate are moved relative to each other, the thickness of the liquid film of the treatment liquid at any of a plurality of positions on the substrate can be accurately measured. Can be measured.

  The distance measuring means may be provided so as to measure the distance to the surface of the liquid film of the processing liquid at least at substantially the center of the upper surface of the substrate.

  In this case, it is possible to accurately measure the distance to the surface of the liquid film of the processing liquid at least at substantially the center of the upper surface of the substrate. Thereby, it is possible to accurately measure the thickness of the liquid film of the processing liquid at least at the center of the upper surface of the substrate.

  The distance measuring means may include a plurality of distance measuring sensors.

  In this case, the distance to the surface of the liquid film of the processing liquid at a plurality of positions on the substrate can be measured. This makes it possible to accurately measure the thickness of the liquid film at a plurality of positions on the substrate.

  The control means causes the treatment liquid supply means to start supplying the treatment liquid, and when the distance to the surface of the liquid film measured by the distance measurement means reaches a predetermined value, The supply operation may be stopped.

  In this case, after the supply of the treatment liquid is started, the supply operation of the treatment liquid is stopped when the distance to the surface of the liquid film measured by the distance measuring unit reaches a predetermined value. It is possible to accurately control the liquid film of the formed processing liquid to a predetermined thickness.

  The distance measuring unit measures the distance to the surface of the liquid film at a plurality of positions, and the control unit uses the processing liquid supply unit based on the distance to the surface of the liquid film at the plurality of positions measured by the distance measuring unit. The processing liquid supply operation may be controlled.

  In this case, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be controlled more accurately.

  In particular, in the case where a moving means for moving the distance measuring means relative to the substrate held by the substrate holding means is further provided or when the distance measuring means includes a plurality of distance measuring sensors, The thickness of the liquid film may be measured, and the processing liquid supply operation may be controlled based on the average value, the minimum value, or the maximum value of the thickness of the liquid film at the plurality of positions.

  The distance measuring means measures the distance to the upper surface of the substrate before forming the processing liquid film by the processing liquid supply means, and reaches the surface of the processing liquid film after forming the processing liquid film by the processing liquid supply means. Calculating means for calculating the thickness of the liquid film based on the difference between the distance to the upper surface of the substrate measured by the distance measuring means and the distance to the surface of the liquid film measured by the distance measuring means May be further provided.

  In this case, the distance to the upper surface of the substrate is measured by the distance measuring means before the formation of the treatment liquid film, and the distance to the surface of the liquid film is measured by the distance measurement means after the formation of the treatment liquid film. The thickness of the liquid film of the processing liquid is calculated by the calculation means based on the difference between the distance to the upper surface of the substrate and the distance to the surface of the liquid film. Therefore, it is possible to automatically measure the thickness of the processing liquid formed on the upper surface of the substrate.

  The treatment is a treatment for removing the resist film formed on the substrate, and the treatment liquid may be a resist removal liquid.

  In this case, a liquid film of a resist stripping liquid having a predetermined thickness can be uniformly formed on the upper surface of the substrate. As a result, the resist film on the substrate can be stripped uniformly.

  The resist stripping solution may be sulfuric acid. In this case, a liquid film of sulfuric acid having a predetermined thickness can be uniformly formed on the upper surface of the substrate. As a result, the resist film on the substrate can be stripped uniformly.

A substrate processing method according to a second aspect of the present invention is a substrate processing method for performing processing on a substrate, the step of holding the substrate substantially horizontally, and supplying the processing liquid onto the held substrate so as to be applied to the upper surface of the substrate. A step of forming a liquid film of the treatment liquid, a step of measuring a distance to the surface of the liquid film of the treatment liquid formed on the upper surface of the substrate, and a treatment liquid based on the measured distance to the surface of the liquid film And a step of controlling the supply operation .

  In the substrate processing method according to the present invention, the substrate is held substantially horizontally, and the processing liquid is supplied onto the held substrate, whereby a liquid film of the processing liquid is formed on the upper surface of the substrate.

The distance to the upper surface of the substrate can be measured before forming the liquid film of the processing liquid. Moreover, the distance to the surface of a liquid film can be measured after formation of the liquid film of a process liquid. Accordingly, the thickness of the liquid film of the treatment liquid is determined based on the difference between the distance to the upper surface of the substrate before the formation of the liquid film of the treatment liquid and the distance to the surface of the liquid film after the formation of the liquid film of the treatment liquid. Can be calculated. Therefore, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately measured.
In addition, by controlling the processing liquid supply operation based on the measured distance to the surface of the liquid film, the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate can be accurately controlled to a predetermined value. Can do.

  According to the present invention, it is possible to accurately measure the thickness of the liquid film of the processing liquid formed on the upper surface of the substrate.

(1) First Embodiment FIG. 1 is a schematic diagram showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention. The substrate processing apparatus according to the present embodiment is a single wafer type resist stripping apparatus that strips a resist film on a substrate.

  The substrate W to be processed by the substrate processing apparatus according to the present embodiment includes a semiconductor wafer, a flat panel display (FPD) substrate, an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, and a photomask substrate. Various substrates such as a substrate are included.

  The substrate processing apparatus of FIG. 1 includes a spin chuck 1 that rotates while holding the substrate W in a substantially horizontal posture. The spin chuck 1 has a rotating shaft 11 extending in the vertical direction and an adsorption base 12 fixed to the upper end of the rotating shaft 11. An intake passage is formed in the suction base 12. By evacuating the suction passage formed in the suction base 12 with the substrate W placed on the suction base 12, the lower surface of the substrate W is vacuum sucked to the suction base 12, and the substrate W is held in a substantially horizontal posture. can do.

  A rotary drive mechanism 13 including a motor is coupled to the rotary shaft 11. When the rotational force is transmitted from the rotation drive mechanism 13 to the rotary shaft 11 while the substrate W is held by the suction base 12, the substrate W is rotated about the vertical axis in a substantially horizontal posture.

  Above the spin chuck 1, a nozzle 2 for supplying sulfuric acid to the upper surface of the substrate W and a soft spray nozzle 3 for supplying a jet of hydrogen peroxide droplets to the upper surface of the substrate W are movable. Is provided.

  An ultrasonic distance measuring sensor (ultrasonic measuring sensor) 4 is movably provided above the spin chuck 1. The ultrasonic distance measuring sensor 4 transmits the ultrasonic wave to the object, receives the ultrasonic wave reflected by the object, and measures the time from transmission to reception of the ultrasonic wave to determine the distance to the object. taking measurement. According to the ultrasonic distance measuring sensor 4, not only an opaque body but also a distance to an object made of a transparent body can be accurately measured.

  On the side of the spin chuck 1, a turning shaft 21 is disposed along the vertical direction, and an arm 22 extending from the upper end of the turning shaft 21 in a substantially horizontal direction is provided. The nozzle 2 is attached to the tip of the arm 22. The turning shaft 21 is coupled with a turning drive mechanism 23 for rotating the turning shaft 21 around the vertical axis and an elevating drive mechanism 24 for moving the turning shaft 21 up and down. The arm 22 can be swung in a horizontal plane above the substrate W held by the spin chuck 1 by reciprocatingly rotating the turning shaft 21 within a predetermined angle range by the turning drive mechanism 23.

A sulfuric acid supply pipe 25 that supplies sulfuric acid (H ₂ SO ₄ ) from a sulfuric acid supply source is connected to the nozzle 2. A sulfuric acid supply valve 27 for controlling discharge of sulfuric acid from the nozzle 2 and a temperature controller 26 for adjusting the temperature of sulfuric acid in order from the sulfuric acid supply source side are inserted in the sulfuric acid supply pipe 25. The temperature controller 26 adjusts the temperature of the sulfuric acid flowing through the sulfuric acid supply pipe 25 to about 80 ° C. The temperature controller 26 can adjust the temperature of sulfuric acid between room temperature and about 80 ° C.

  Further, a turning shaft 31 is disposed along the vertical direction on the side of the spin chuck 1, and an arm 32 extending in a substantially horizontal direction from the upper end portion of the turning shaft 31 is provided. A soft spray nozzle 3 is attached to the tip of the arm 32. The turning shaft 31 is coupled to a turning drive mechanism 33 that rotates the turning shaft 31 around a vertical axis and an elevating drive mechanism 34 that moves the turning shaft 31 up and down. The arm 32 can be swung in a horizontal plane above the substrate W held by the spin chuck 1 by reciprocatingly rotating the swing shaft 31 within a predetermined angle range by the swing drive mechanism 33.

The soft spray nozzle 3 is supplied with a nitrogen gas supply pipe 35 that supplies high-pressure nitrogen gas (N ₂ ) from a nitrogen gas supply source and hydrogen peroxide water (H ₂ O ₂ ) from a hydrogen peroxide solution supply source. A hydrogen peroxide solution supply pipe 38 to be supplied is connected. When high-pressure nitrogen gas and hydrogen peroxide water are simultaneously supplied to the soft spray nozzle 3, nitrogen gas and hydrogen peroxide water are mixed in the droplet formation chamber (mixing chamber) in the soft spray nozzle 3, resulting in peroxidation. Fine droplets of hydrogen water are formed. The droplets of the hydrogen peroxide solution form a jet and are supplied from the tip of the soft spray nozzle 3 to the upper surface of the substrate W.

  The nitrogen gas supply pipe 35 is provided with a temperature regulator 36 for adjusting the temperature of the nitrogen gas in order from the nitrogen gas supply source side and a nitrogen gas supply valve 37 for controlling the supply of the nitrogen gas to the soft spray nozzle 3. It is inserted. The temperature controller 36 adjusts the temperature of the nitrogen gas flowing through the nitrogen gas supply pipe 35 to about 80 ° C. The temperature controller 36 can adjust the temperature of the nitrogen gas between room temperature and about 80 ° C.

  The hydrogen peroxide solution supply pipe 38 is supplied with hydrogen peroxide solution to the temperature controller 39 and the soft spray nozzle 3 for adjusting the temperature of the hydrogen peroxide solution in order from the hydrogen peroxide solution supply source side. A hydrogen peroxide supply valve 40 for control is inserted. The temperature controller 39 adjusts the temperature of the hydrogen peroxide solution flowing through the hydrogen peroxide solution supply pipe 38 to about 40 ° C. The temperature controller 39 can adjust the temperature of the hydrogen peroxide solution between room temperature and about 80 ° C.

  Further, on the side of the spin chuck 1, a turning shaft 41 is arranged along the vertical direction, and an arm 42 extending in a substantially horizontal direction from the upper end portion of the turning shaft 41 is provided. An ultrasonic distance measuring sensor 4 is attached to the tip of the arm 42. The turning shaft 41 is coupled to a turning drive mechanism 43 that rotates the turning shaft 41 around a vertical axis. The revolving rotation of the swivel shaft 41 within a predetermined angle range by the swivel drive mechanism 43 allows the arm 42 to swing in the horizontal plane above the substrate W held by the spin chuck 1.

  FIG. 2 is a schematic plan view of the main part of the substrate processing apparatus of FIG.

  As shown in FIG. 2, the arm 22 can be swung above the substrate W by rotating the turning shaft 21 by the turning drive mechanism 23 shown in FIG. As a result, the nozzle 2 can be moved in the radial direction of the substrate W between the outer standby position of the substrate W and the central portion of the substrate W as indicated by an arrow P.

  Further, the arm 32 can be swung above the substrate W by rotating the turning shaft 31 by the turning drive mechanism 33 of FIG. As a result, the soft spray nozzle 3 can be moved in the radial direction of the substrate W between the standby position outside the substrate W and the central portion of the substrate W as indicated by an arrow Q.

  Furthermore, the arm 42 can be swung above the substrate W by rotating the turning shaft 41 by the turning drive mechanism 43 of FIG. As a result, the ultrasonic distance measuring sensor 4 is moved from the standby position outside the substrate W through the one outer peripheral portion of the substrate W and the substantially central portion of the substrate W as shown by the arrow R. It can be moved to the outer periphery. Therefore, the distance to the upper surface of the substrate W can be measured at an arbitrary position of the substrate W by the ultrasonic distance measuring sensor 4.

  FIG. 3 is a block diagram showing a configuration of a control system in the substrate processing apparatus of FIG.

  The control unit 50 includes a CPU (Central Processing Unit), a memory, and the like. The control unit 50 receives a detection signal from the ultrasonic distance measuring sensor 4, and according to a predetermined control program, the rotation drive mechanism 13, the swing drive mechanism 23, the lift drive mechanism 24, the swing drive mechanism 33, and the lift drive mechanism. 34, the turning drive mechanism 43, the sulfuric acid supply valve 27, the nitrogen gas supply valve 37, and the hydrogen peroxide solution supply valve 37 are controlled.

  FIG. 4 is a flowchart showing resist stripping processing by the substrate processing apparatus of FIG. This resist stripping process is performed by the control unit 50 controlling each unit in FIG. 3 according to a predetermined control program.

  First, the substrate W on which the resist film is formed is carried into the spin chuck 1 by a substrate transfer device (not shown). The controller 50 moves the ultrasonic distance measuring sensor 4 to substantially the center of the substrate W by rotating the turning shaft 41 by the turning drive mechanism 43.

  The ultrasonic distance measuring sensor 4 measures the distance to the upper surface of the substrate W (step S1), and gives a detection signal indicating the measured value to the control unit 50. In this case, the control unit 50 moves the ultrasonic distance measuring sensor 4 in the radial direction above the substrate W by the turning drive mechanism 43, so that the substrate W at any one or more positions of the substrate W is moved. The distance to the top surface can be measured.

  Next, the control unit 50 moves the nozzle 2 above the center portion of the substrate W by the turning drive mechanism 23 and the lift drive mechanism 24. In this state, the controller 50 opens the sulfuric acid supply valve 27 to supply sulfuric acid from the nozzle 2 to the center of the upper surface of the substrate W (step S2). At this time, the rotation drive mechanism 13 is not operating, and the substrate W is stationary. The sulfuric acid supplied to the upper surface of the substrate W spreads from the center of the upper surface of the substrate W to the outer peripheral portion, and a liquid film LF is formed on the upper surface of the substrate W by the surface tension.

  Further, the controller 50 rotates the substrate W at a low speed by the rotation drive mechanism 13 so that the sulfuric acid liquid film LF spreads uniformly over almost the entire upper surface of the substrate W (step S3). Specifically, after a predetermined amount of sulfuric acid is supplied to the central portion of the upper surface of the substrate W while the substrate W is stationary, the sulfuric acid is held on the spin chuck 1 by the rotary drive mechanism 13 while continuing to supply this sulfuric acid. The rotation speed of the substrate W is gradually increased to a relatively low rotation speed of 10 to 20 rpm, for example.

  The ultrasonic distance measuring sensor 4 measures the distance to the surface of the liquid film LF formed on the upper surface of the substrate W (step S4), and gives a detection signal indicating the measured value to the control unit 50. The control unit 50 calculates the thickness of the liquid film LF of sulfuric acid formed on the upper surface of the substrate W based on the detection signal given from the ultrasonic distance measuring sensor 4, and the thickness of the liquid film LF on the upper surface of the substrate W. It is determined whether or not the value has reached a predetermined value (step S5).

  In this case, the control unit 50 moves the ultrasonic distance measuring sensor 4 in the radial direction above the substrate W by the turning drive mechanism 43, so that the distance to the surface of the liquid film LF at an arbitrary position on the substrate W is reached. Can be measured. Thereby, the thickness of the liquid film LF at an arbitrary position on the substrate W can be calculated.

  Here, the arbitrary position may be, for example, one position in the vicinity of the rotation center of the substrate W or one position on the peripheral edge of the substrate. Alternatively, any plurality of positions on the locus drawn by the ultrasonic distance measuring sensor 4 on the substrate W may be used. Further, the plurality of arbitrary positions may be a plurality of positions having a predetermined interval on the trajectory, or may be a plurality of substantially continuous positions having a small interval.

  For example, when an arbitrary position is one position near the rotation center of the substrate W, the control is performed when the thickness of the liquid film LF on the upper surface of the substrate W does not reach a predetermined value (for example, 1.0 mm). The unit 50 returns to step S2 and continues to supply sulfuric acid from the nozzle 2 to the upper surface of the substrate W.

  When the thickness of the liquid film LF on the upper surface of the substrate W reaches the predetermined value in step S4, the controller 50 stops the supply of sulfuric acid from the nozzle 2 by closing the sulfuric acid supply valve 27 (step S4). S6).

  Further, for example, when an arbitrary position is a plurality of positions on the substrate W, in step S5, the average value of the thickness of the liquid film LF at the plurality of positions is compared with the predetermined value. Alternatively, it may be compared with the minimum value or the maximum value of a plurality of positions instead of the average value. Further, the determination may be made by a combination of at least two of the average value, the minimum value, and the maximum value. For example, step S5 is set such that the average value ≧ 1.0 mm and the minimum value ≧ 0.5 mm. It is good also as a condition.

  In this way, the sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the upper surface of the substrate W.

  Thereafter, the control unit 50 moves the nozzle 2 from above the substrate W to a standby position outside the substrate W by the turning drive mechanism 23 and the elevation drive mechanism 24. Next, the control unit 50 moves the soft spray nozzle 3 from the standby position outside the substrate W to a position above the substrate W by the turning drive mechanism 33 and the elevation drive mechanism 34.

  At this time, the substrate W continues to rotate at a low speed (10 to 20 rpm) from the time when the sulfuric acid is supplied. In this state, the control unit 50 opens the nitrogen gas supply valve 37 and the hydrogen peroxide solution supply valve 40 so that the hydrogen peroxide solution at approximately 40 ° C. is applied from the soft spray nozzle 3 to the liquid film LF on the upper surface of the substrate W. A droplet jet is supplied (step S7). Further, the control unit 50 moves the soft spray nozzle 3 from the center of the substrate W to the substrate W while the jet of hydrogen peroxide water droplets is supplied to the liquid film LF on the upper surface of the substrate W. Is repeatedly moved while drawing an arc-shaped trajectory within a range extending to the outer peripheral portion.

  While rotating the substrate W by the spin chuck 1 and scanning the jet of the hydrogen peroxide solution on the upper surface of the substrate W, the droplet of the hydrogen peroxide solution is uniformly jetted over the entire upper surface of the substrate W. Can be supplied.

A chemical reaction between sulfuric acid and hydrogen peroxide solution is performed on the substrate W by supplying a jet of hydrogen peroxide solution droplets from the soft spray nozzle 3 to the sulfuric acid liquid film LF formed on the upper surface of the substrate W. (H ₂ SO ₄ + H ₂ O ₂ → H ₂ SO ₅ + H ₂ O) is generated, and a resist stripping solution containing sulfuric acid having strong oxidizing power is generated. The temperature of the sulfuric acid liquid film LF formed on the upper surface of the substrate W is about 80 ° C., and the temperature of the hydrogen peroxide solution supplied from the soft spray nozzle 3 is about 40 ° C. The temperature of the resist stripping solution containing sulfuric acid reaches a temperature at which the resist film formed on the substrate W can be satisfactorily stripped (about 100 ° C. to 120 ° C.) due to the reaction product heat generated during the chemical reaction with hydrogen water. .

  Further, since the droplet jet from the soft spray nozzle 3 has a large kinetic energy (flow velocity), the droplet jet having a large kinetic energy is supplied to the upper surface of the substrate W, thereby supplying the droplet. The resist film formed at the position is physically peeled off. That is, the resist film formed on the substrate W is chemically and physically peeled off and removed by the oxidizing power of the sulfuric acid liquid film LF and the kinetic energy of the droplet jet from the soft spray nozzle 3.

  When the time necessary and sufficient for removing the resist film formed on the substrate W has elapsed, the control unit 50 closes the nitrogen gas supply valve 37 and the hydrogen peroxide solution supply valve 40. Further, the control unit 50 moves the soft spray nozzle 3 from a position above the substrate W to a standby position outside the substrate W by the turning drive mechanism 33 and the elevation drive mechanism 34.

  Next, the controller 50 performs a rinsing process for washing away the resist stripping solution (sulfuric acid and hydrogen peroxide solution) remaining on the surface of the substrate W with pure water for a predetermined time (step S8). That is, the control unit 50 supplies pure water from the pure water nozzle (not shown) to the upper surface of the substrate W while rotating the substrate W at a predetermined rotation speed (for example, about 1500 rpm) by the rotation drive mechanism 13. The pure water supplied to the upper surface of the substrate W receives a centrifugal force due to the rotation of the substrate W, and flows from the supply position toward the outer peripheral portion of the substrate W. Thus, pure water spreads over the entire upper surface of the substrate W, and the resist stripping solution is washed away from the surface of the substrate W by the pure water.

  Thereafter, the control unit 50 performs the drying process by rotating the spin chuck 1 at a high speed (for example, about 3000 rpm) for a predetermined drying time by the rotation drive mechanism 13 (step S9). Thereby, pure water is spun off from the upper surface of the substrate W by centrifugal force, and the upper surface of the substrate W is dried. After the drying process is completed, the control unit 50 stops the rotation of the spin chuck 1. Thereafter, the processed substrate W is unloaded from the spin chuck 1 by a substrate transfer device (not shown).

  In the substrate processing apparatus of the present embodiment, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the distance to the upper surface of the substrate W at an arbitrary position of the substrate W is measured. After the formation of the sulfuric acid liquid film LF, the distance to the surface of the sulfuric acid liquid film LF at any position of the substrate W can be measured.

  Thus, the thickness of the sulfuric acid liquid film LF at an arbitrary position on the substrate W can be accurately measured. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

  In the present embodiment, the spin chuck 1 corresponds to a substrate holding unit, the nozzle 2 corresponds to a processing liquid supply unit, and the ultrasonic distance measuring sensor 4 corresponds to a distance measuring unit or an ultrasonic distance measuring sensor. Further, the turning shaft 41, the arm 42, and the turning drive mechanism 43 correspond to a moving unit, and the control unit 50 corresponds to a control unit and a calculating unit.

(2) Second Embodiment FIG. 5 is a schematic view showing a configuration of a substrate processing apparatus according to a second embodiment of the present invention. The substrate processing apparatus according to the present embodiment is a single-wafer type resist stripping apparatus that strips a resist film on a substrate, similarly to the substrate processing apparatus of the first embodiment.

  The substrate processing apparatus of FIG. 5 is different from the substrate processing apparatus of FIG. 1 in that a plurality of ultrasonic distances are used instead of the ultrasonic distance measuring sensor 4, the turning shaft 41, the arm 42 and the turning drive mechanism 43 of FIG. The measurement sensors 4A, 4B, 4C are attached to the support plate 45. The support plate 45 is fixed above the spin chuck 1. In the present embodiment, three ultrasonic distance measuring sensors 4A, 4B, and 4C are attached to the support plate 45.

  The structure of the other part of the substrate processing apparatus of FIG. 5 is the same as that of the substrate processing apparatus of FIG. In FIG. 5, the sulfuric acid supply pipe 25, the temperature controller 26, the sulfuric acid supply valve 27, the nitrogen supply pipe 35, the temperature controller 36, the nitrogen supply valve 37, the hydrogen peroxide solution supply pipe 38, and the like shown in FIG. Illustration of the temperature controller 39 and the hydrogen peroxide solution supply valve 40 is omitted.

  FIG. 6 is a schematic plan view of the main part of the substrate processing apparatus of FIG. As shown in FIG. 6, the arm 22 can be swung above the substrate W by rotating the turning shaft 21 by the turning drive mechanism 23 of FIG. As a result, the nozzle 2 can be moved in the radial direction of the substrate W between the outer standby position of the substrate W and the central portion of the substrate W as indicated by an arrow P.

  Further, the arm 32 can be swung above the substrate W by rotating the turning shaft 31 by the turning drive mechanism 33 of FIG. As a result, the soft spray nozzle 3 can be moved in the radial direction of the substrate W between the standby position outside the substrate W and the central portion of the substrate W as indicated by an arrow Q.

  The ultrasonic distance measuring sensor 4A is held at a substantially central position of the substrate W by the support plate 45 of FIG. The ultrasonic distance measuring sensor 4B is held at a position between the central portion and the outer peripheral portion of the substrate W by the support plate 45 of FIG. Further, the ultrasonic distance measuring sensor 4C is held at a position near the outer peripheral portion of the substrate W by the support plate 45 of FIG. Accordingly, the upper surface of the substrate W at the position of the substantially central portion of the substrate W, the position between the central portion and the outer peripheral portion, and the position near the outer peripheral portion using the three ultrasonic distance measuring sensors 4A, 4B, and 4C. Can be measured.

  In the substrate processing apparatus of the present embodiment, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the position of the substantially central portion of the substrate W, the position between the central portion and the outer peripheral portion, and the vicinity of the outer peripheral portion. After the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the position of the substrate W, the position between the central portion and the outer peripheral portion, and the outer periphery are measured. The distance to the surface of the liquid film LF of sulfuric acid at a position near the part can be measured.

  Thereby, it is possible to accurately measure the thickness of the sulfuric acid liquid film LF at three positions, that is, the position of the substantially central portion of the substrate W, the position between the central portion and the outer peripheral portion, and the position near the outer peripheral portion. Become. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

  Specifically, as in the first embodiment, the controller 50 controls the sulfuric acid supply valve 27 based on the average value, the minimum value, or the maximum value of the thickness of the liquid film LF at these three positions. The opening / closing operation may be controlled, or the supply of sulfuric acid may be controlled based on a combination of at least two of the average value, the maximum value, and the minimum value.

  Thus, if the supply of sulfuric acid is controlled based on the thickness of the liquid film LF at a plurality of positions, the treatment of sulfuric acid on the surface of the substrate W can be made uniform.

  In the present embodiment, the ultrasonic distance measuring sensors 4A, 4B, and 4C correspond to distance measuring means or ultrasonic distance measuring sensors.

  In the substrate processing apparatus of FIG. 5, the holding plate 45 may be movably provided by the same structure as the turning shaft 41, the arm 42, and the turning drive mechanism 43 in the substrate processing apparatus of FIG. 1.

  In the first and second embodiments, the ultrasonic distance measuring sensors 4, 4A, 4B, and 4C are used only for measuring the thickness of the liquid film LF on the substrate W. In addition, it may be used for detecting the presence / absence of the substrate W on the spin chuck 1 and the mounting state (substrate displacement or inclination). In this case, the distance to the upper surface of the substrate W placed on the spin chuck 1 can be measured at any one or a plurality of positions by the ultrasonic distance measuring sensors 4, 4A, 4B, 4C.

(3) Third Embodiment FIG. 7 is a schematic diagram showing the configuration of the main part of a substrate processing apparatus according to a third embodiment of the present invention. The substrate processing apparatus according to the present embodiment is a single-wafer type resist stripping apparatus that strips a resist film on a substrate, similarly to the substrate processing apparatus of the first embodiment.

  The substrate processing apparatus of FIG. 7 is different from the substrate processing apparatus of FIG. 1 in that a laser distance measuring sensor (laser displacement sensor) 40a is used instead of the ultrasonic distance measuring sensor 4 of FIG. . The laser type distance measuring sensor 40 a is attached to the tip of the arm 42 and is movable above the spin chuck 1, similarly to the ultrasonic distance measuring sensor 4 of FIG. 1. The configuration of other parts of the substrate processing apparatus of FIG. 7 is the same as the configuration of the substrate processing apparatus of FIG. In the present embodiment, the laser distance measuring sensor 40a corresponds to a distance measuring means or a laser distance measuring sensor.

  FIG. 8 is a schematic diagram for explaining the configuration and operating principle of the laser distance measuring sensor 40a of FIG.

  As shown in FIG. 8, the laser type distance measuring sensor 40 a includes a laser light source 401, a CCD (charge coupled device) 402, and a light receiving lens 403. The laser beam emitted from the laser light source 401 is applied to the object OB. Reflected light from the object OB is received by the light receiving surface of the CCD 402 through the light receiving lens 403. In the laser type distance measuring sensor 40a, the distance to the object OB can be measured with high resolution (for example, 0.1 μm) by the triangular distance measuring method.

  As indicated by a solid arrow in FIG. 8, when the object OB is located at a position close to the laser distance measuring sensor 40a, the angle θ1 formed by the light incident on the object OB and the light incident on the CCD 402 is large. Become. On the other hand, as shown by a dotted arrow in FIG. 8, when the object OB is at a position far from the laser distance measuring sensor 40a, an angle θ2 formed between the incident light on the object OB and the incident light on the CCD 402. Becomes smaller. Thereby, the position of the light spot formed on the light receiving surface of the CCD 402 changes depending on the distance from the laser type distance measuring sensor 40a to the object OB. The laser distance measuring sensor 40 a outputs a voltage signal proportional to the distance to the object OB by detecting the position of the light spot on the light receiving surface of the CCD 402. Therefore, the distance to the object OB can be measured based on the voltage signal output from the laser type distance measuring sensor 40a.

  In the substrate processing apparatus of the present embodiment, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the distance to the upper surface of the substrate W at an arbitrary position of the substrate W is measured by the laser type distance measuring sensor 40a. After the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the distance to the surface of the sulfuric acid liquid film LF at an arbitrary position of the substrate W can be measured by the laser distance measuring sensor 40a.

  Thus, as in the first embodiment, the thickness of the sulfuric acid liquid film LF at an arbitrary position on the substrate W can be accurately measured. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

  In the substrate processing apparatus shown in FIG. 5, three laser distance measuring sensors 40a may be used instead of the plurality of ultrasonic distance measuring sensors 4A, 4B, 4C. In this case, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the three laser-type distance measuring sensors 40a are used to determine the position of the central portion of the substrate W between the central portion and the outer peripheral portion. And the distance to the upper surface of the substrate W at the position in the vicinity of the outer peripheral portion, and after the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the three laser-type distance measuring sensors 40a are used to measure the substrate W. It is possible to measure the distance to the surface of the sulfuric acid liquid film LF at a substantially central position, a position between the central portion and the outer peripheral portion, and a position in the vicinity of the outer peripheral portion.

  Accordingly, as in the second embodiment, the thickness of the sulfuric acid liquid film LF at the position of the substantially central portion of the substrate W, the position between the central portion and the outer peripheral portion, and the position near the outer peripheral portion is accurately determined. It becomes possible to measure. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

(4) Fourth Embodiment FIG. 9 is a schematic view showing the configuration of the main part of a substrate processing apparatus according to a fourth embodiment of the present invention. The substrate processing apparatus according to the present embodiment is a single-wafer type resist stripping apparatus that strips a resist film on a substrate, similarly to the substrate processing apparatus of the first embodiment.

  The substrate processing apparatus of FIG. 9 is different from the substrate processing apparatus of FIG. 1 in that a microwave distance measuring sensor (microwave displacement sensor) 40b is used instead of the ultrasonic distance measuring sensor 4 of FIG. It is. Similarly to the ultrasonic distance measuring sensor 4 of FIG. 1, the microwave distance measuring sensor 40 b is attached to the tip of the arm 42 and is movable above the spin chuck 1. The configuration of other parts of the substrate processing apparatus of FIG. 9 is the same as the configuration of the substrate processing apparatus of FIG. In the present embodiment, the microwave distance measuring sensor 40b corresponds to a distance measuring means or a microwave distance measuring means.

  The microwave distance measuring sensor 40b of FIG. 9 transmits a radio wave of a microwave band such as an X band to an object, receives a radio wave reflected by the object, and based on a time difference from transmission to reception. Measure the distance to the object.

  The microwave distance measuring sensor 40b outputs a voltage signal proportional to the distance to the object. Therefore, the distance to the object can be measured based on the voltage signal output from the microwave distance measuring sensor 40b. According to the microwave distance measuring sensor 40b, it is possible to accurately measure not only the opaque body but also the object made of the transparent body.

  In the substrate processing apparatus of the present embodiment, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the distance to the upper surface of the substrate W at an arbitrary position of the substrate W is measured by the microwave distance measuring sensor 40b. After the measurement and formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the distance to the surface of the sulfuric acid liquid film LF at any position of the substrate W can be measured by the microwave distance measuring sensor 40b.

  Thus, as in the first embodiment, the thickness of the sulfuric acid liquid film LF at an arbitrary position on the substrate W can be accurately measured. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

  In the substrate processing apparatus shown in FIG. 5, three microwave distance measuring sensors 40b may be used instead of the plurality of ultrasonic distance measuring sensors 4A, 4B, 4C. In this case, before the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the three microwave distance measuring sensors 40b are used to determine the position of the central portion of the substrate W, the central portion and the outer peripheral portion. The distance to the upper surface of the substrate W at the position between and in the vicinity of the outer peripheral portion is measured, and after the formation of the sulfuric acid liquid film LF on the upper surface of the substrate W, the substrate is measured using the three microwave distance measuring sensors 40b. It is possible to measure the distance to the surface of the sulfuric acid liquid film LF at a substantially central position of W, a position between the central part and the outer peripheral part, and a position near the outer peripheral part.

  Accordingly, as in the second embodiment, the thickness of the sulfuric acid liquid film LF at the position of the substantially central portion of the substrate W, the position between the central portion and the outer peripheral portion, and the position near the outer peripheral portion is accurately determined. It becomes possible to measure. As a result, a sulfuric acid liquid film LF having a predetermined thickness can be uniformly formed on the substrate W.

(5) Other Modifications In the above-described embodiment, the case where the substrate processing apparatus according to the present invention is applied to a substrate processing apparatus that performs resist stripping processing has been described. Various development devices such as a developing device that performs development processing using a polymer, a polymer removal cleaning device that performs polymer removal cleaning using a cleaning liquid, and a device that performs oxidation processing of a substrate surface using an oxidizing solution such as ozone water or hydrogen peroxide It can be applied to a substrate processing apparatus.

  The present invention can be used to perform various processes using a processing liquid on a substrate.

It is the schematic which shows the structure of the substrate processing apparatus which concerns on the 1st Embodiment of this invention. It is a schematic plan view of the principal part of the substrate processing apparatus of FIG. It is a block diagram which shows the structure of the control system in the substrate processing apparatus of FIG. It is a flowchart which shows the resist peeling process by the substrate processing apparatus of FIG. It is the schematic which shows the structure of the substrate processing apparatus which concerns on the 2nd Embodiment of this invention. It is a schematic plan view of the principal part of the substrate processing apparatus of FIG. It is the schematic which shows the structure of the principal part of the substrate processing apparatus which concerns on the 3rd Embodiment of this invention. It is a schematic diagram for demonstrating the structure and operating principle of the laser type distance measuring sensor of FIG. It is the schematic which shows the structure of the principal part of the substrate processing apparatus which concerns on the 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spin chuck 2 Nozzle 3 Soft spray nozzle 4,4A, 4B, 4C Ultrasonic distance measuring sensor 13 Rotation drive mechanism 21,31,41 Rotating shaft 22,32,42 Arm 23,33,43 Rotation drive mechanism 24,34 Elevating drive mechanism 40a Laser distance measuring sensor 40b Microwave distance measuring sensor 45 Support plate 50 Control unit 401 Laser light source 402 CCD
403 Light receiving lens W Substrate LF Liquid film

Claims (13)

A substrate processing apparatus for performing processing using a processing liquid on a substrate,
Substrate holding means for holding the substrate substantially horizontally;
A processing liquid supply means for forming a liquid film of the processing liquid on the upper surface of the substrate by supplying the processing liquid onto the substrate held by the substrate holding means;
Distance measuring means for measuring the distance to the surface of the liquid film of the processing liquid formed on the upper surface of the substrate ;
A substrate processing apparatus comprising: a control unit that controls a processing liquid supply operation by the processing liquid supply unit based on a distance to the surface of the liquid film measured by the distance measuring unit . The substrate processing apparatus according to claim 1, wherein the distance measuring unit includes an ultrasonic distance measuring sensor. The substrate processing apparatus according to claim 1, wherein the distance measuring unit includes a laser type distance measuring sensor. The substrate processing apparatus according to claim 1, wherein the distance measuring unit includes a microwave distance measuring sensor. 5. The substrate processing apparatus according to claim 1, further comprising a moving unit that moves the distance measuring unit relative to the substrate held by the substrate holding unit. The substrate processing according to claim 1, wherein the distance measuring unit is provided so as to measure a distance to a liquid film of the processing liquid at least at a substantially central portion of the upper surface of the substrate. apparatus. The substrate processing apparatus according to claim 1, wherein the distance measuring unit includes a plurality of distance measuring sensors. When the distance to the surface of the liquid film measured by the distance measuring unit reaches a predetermined value after causing the processing liquid supply unit to start supplying the processing liquid, the control unit supplies the processing liquid supply unit. the substrate processing apparatus according to any one of claims 1 to 7, characterized in that to stop the supply operation of the processing solution. The distance measuring means measures the distance to the surface of the liquid film at a plurality of positions,
The control means controls the processing liquid supply operation by the processing liquid supply means based on the distance to the surface of the liquid film at a plurality of positions measured by the distance measuring means . The substrate processing apparatus according to claim 8 . The distance measuring means measures the distance to the upper surface of the substrate before the formation of the treatment liquid film by the treatment liquid supply means, and after the formation of the treatment liquid film by the treatment liquid supply means, Measure the distance to the surface of the liquid film,
The thickness of the liquid film of the processing liquid based on the difference between the distance to the upper surface of the substrate measured by the distance measuring means and the distance to the surface of the liquid film of the processing liquid measured by the distance measuring means. the substrate processing apparatus according to any one of claims 1 to 9, further comprising a calculating means for calculating. The process is a process of peeling a resist film formed on a substrate,
Said processing liquid, the substrate processing apparatus according to any one of claims 1 to 10, characterized in that a resist stripping solution. 12. The substrate processing apparatus according to claim 11, wherein the resist stripping solution is sulfuric acid. A substrate processing method for performing processing using a processing liquid on a substrate,
A step of holding the substrate almost horizontally;
Forming a liquid film of the processing liquid on the upper surface of the substrate by supplying the processing liquid onto the held substrate;
Measuring the distance to the surface of the liquid film of the treatment liquid formed on the upper surface of the substrate ;
And a step of controlling the supply operation of the processing liquid based on the measured distance to the surface of the liquid film .

Images