JP3727166B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus having a step-out detection function of a pulse motor.
[0002]
[Prior art]
A substrate processing apparatus is used to perform predetermined processing on a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, and a substrate for an optical disk.
[0003]
FIG. 7 is a schematic diagram showing a configuration of a conventional rotary coating apparatus as an example of a substrate processing apparatus. In FIG. 7, the rotary coating apparatus includes a substrate holding unit 2 that holds a substrate W and a spin motor 1 that rotationally drives the substrate holding unit 2. Further, the rotary coating apparatus is provided with a resist solution supply system 3 for supplying a resist solution to the surface of the substrate W.
[0004]
The resist solution supply system 3 includes a resist container 8 that stores the resist solution 9, a resist nozzle 4 that discharges the resist solution 9, and a resist supply pipe 5 that communicates the resist container 8 with the resist nozzle 4. In the middle of the resist supply pipe 5, a discharge pump 6 for sending the resist solution 9 from the resist container 8 to the resist nozzle 4 is provided.
[0005]
The discharge pump 6 is driven by a pump drive motor 7 composed of a pulse motor. The pump drive motor 7 is rotationally driven by a drive signal output from the motor controller 10 under the control of the main controller 11.
[0006]
Then, the resist solution 9 discharged onto the surface of the substrate W receives a centrifugal force due to the rotation of the substrate W, and is uniformly spread over the entire surface of the substrate W. As a result, a resist thin film is formed on the substrate W.
[0007]
In recent years, in order to form a fine pattern on the resist thin film on the substrate W, it is required to control the thickness of the resist thin film thinly and accurately. The film thickness of the resist thin film depends on the discharge amount of the resist liquid 9 discharged from the resist nozzle 4 to the substrate W. Further, the discharge amount of the resist solution 9 from the resist nozzle 4 is defined by the rotation amount of the pump drive motor 7 that drives the discharge pump 6. Therefore, it is required to accurately control the rotational operation of the pump drive motor 7.
[0008]
For this reason, in the conventional rotary coating apparatus, the encoder 12 is attached to the pump drive motor 7, and the rotation speed of the pump drive motor 7 is detected by the output from the encoder 12. By detecting the rotational speed of the pump drive motor 7, it is possible to detect the amount of operation of the discharge pump 6 that operates in accordance with the rotation of the pump drive motor 7, and thereby the resist discharged from the resist nozzle 4 onto the substrate W. The amount of the liquid 9 can be grasped.
[0009]
[Problems to be solved by the invention]
Recently, various resist solutions have been developed in response to demands for miniaturization and high integration of semiconductor devices. In the conventional rotary coating apparatus, a plurality of resist liquid supply systems 3 are provided to select and supply an appropriate resist liquid according to the type of the substrate W. In this case, the pump drive motor 7 to which the discharge pump 6 and the encoder 12 are attached also needs to be installed for each resist solution supply system 3, and the occupied area in the rotary coating apparatus becomes relatively large, and the rotary coating is performed. It becomes a factor which enlarges the whole apparatus.
[0010]
On the other hand, in a clean room in which a substrate processing apparatus such as a rotary coating apparatus is installed, it is required to suppress an installation area (footprint) of the substrate processing apparatus in order to reduce equipment costs. For this reason, for example, in a rotary coating apparatus, even when the resist solution supply system 3 is added, a structure capable of suppressing an increase in the size of the entire rotary coating apparatus is desired.
[0011]
Further, not only in the rotary coating apparatus but also in other substrate processing apparatuses provided with a pulse motor having an encoder or the like, it is desired to simplify the structure around the pulse motor.
[0012]
An object of the present invention is to provide a substrate processing apparatus that can detect step-out of a pulse motor, can simplify the structure around the pulse motor, and can suppress an increase in size of the apparatus.
[0013]
[Means for Solving the Problems and Effects of the Invention]
The inventors studied to omit the encoder 12 in the process of simplifying the structure around the pulse motor provided in the substrate processing apparatus. In this case, simply omitting the encoder 12 makes it impossible to confirm whether the pulse motor has operated as controlled. Therefore, the following substrate processing apparatus has been devised in order to detect the step-out of the pulse motor and to simplify the structure.
[0014]
  A substrate processing apparatus according to a first aspect of the present invention is a substrate processing apparatus that performs a predetermined process on a substrate, and performs a predetermined process on a substrate holding unit that holds the substrate and a substrate held on the substrate holding unit. A processing unit, a moving member provided so as to be movable in relation to processing in the processing unit, a pulse motor that moves the moving member in one direction or in a reverse direction, and pulse generation means that applies a driving pulse to the pulse motor; A detected member that is provided on the moving member and reciprocates between the origin position and the end point position as the moving member moves in one direction or in the opposite direction, and a detection position that is a fixed distance away from the origin position to the end point position side And detecting means for detecting that the moving member has reached the detection position, and from the pulse generating means to the pulse motor while the detected member moves from the origin position to the detection position when moving in one direction of the moving member. Give The number of drive pulses, the number of drive pulses which the sensing member upon movement in the opposite direction is given from the pulse generating means to stop after reaching the detection position to the pulse motor of the moving memberIf the motors are different, it is determined that a step-out has occurred in the pulse motor while moving the moving member in one direction or the opposite direction.And step-out detection means.
[0015]
In the substrate processing apparatus according to the first aspect of the invention, the processing unit performs a predetermined process on the substrate held by the substrate holding unit by moving the moving member. The moving member is driven by a pulse motor. The driving amount of the pulse motor is controlled by the number of driving pulses given from the pulse generating means. Accordingly, the amount of movement of the moving member in one direction or in the opposite direction is regulated to the same amount by the number of drive pulses applied to the pulse motor during normal operation of the pulse motor. However, when a step-out occurs in the pulse motor, the rotation amount of the pulse motor corresponding to the number of drive pulses is different from the actual rotation amount of the pulse motor.
[0016]
  Therefore, the moving member driven by the pulse motor moves in one direction, and the number of drive pulses given from the pulse generating means to the pulse motor while the detected member moves from the origin position to the detection position is reversed. The number of drive pulses given to the pulse motor by moving in the direction and obtaining the number of drive pulses given to the pulse motor from the pulse generating means until the detected member reaches the detection position and stops Detects whether there is a difference between the amount of rotation of the pulse motor according to the actual amount of rotation of the pulse motor, andWhile moving the moving member in one direction or in the opposite directionThe presence / absence of a step-out of the pulse motor can be detected. Therefore, it is possible to detect step-out of the pulse motor without providing an encoder in the pulse motor, the structure of the substrate processing apparatus can be simplified, and an increase in the size of the apparatus can be suppressed.
[0017]
A substrate processing apparatus according to a second aspect of the present invention is the substrate processing apparatus according to the first aspect, wherein the detected member moves from the origin position to the detection position when the step-out detection means moves in one direction of the moving member. During this time, the number of drive pulses given to the pulse motor from the pulse generating means is counted as the first pulse number, and when the detected member reaches the detection position and stops when the moving member moves in the reverse direction. Counting means for counting the number of drive pulses given from the pulse generating means to the pulse motor as the second pulse number, and a pulse when the first pulse number and the second pulse number obtained by the counting means are different Determining means for determining that a step-out has occurred in the motor.
[0018]
In this case, the determining means is based on whether or not there is a difference between the number of driving pulses counted when the moving member moves in one direction and the number of driving pulses counted when moving in the reverse direction. However, it is possible to easily determine whether or not the pulse motor is out of step.
[0019]
  A substrate processing apparatus according to a third aspect of the invention is a substrate processing apparatus that performs a predetermined process on a substrate, and performs a predetermined process on a substrate holding unit that holds the substrate and a substrate held on the substrate holding unit. A processing unit, a moving member provided so as to be movable in relation to processing in the processing unit, a pulse motor that moves the moving member in one direction or in a reverse direction, and pulse generation means that applies a driving pulse to the pulse motor; A detected member that is provided on the moving member and reciprocates between the origin position and the end point position as the moving member moves in one direction or in the opposite direction, and a detection position that is a fixed distance away from the origin position to the end point position side And detecting means for detecting that the moving member has reached the detection position, and from the pulse generating means to the pulse motor while the detected member moves from the detection position to the end position when moving in one direction of the moving member. Give The number of drive pulses, the number of drive pulses reverse to the detected member when moving is given to the pulse motor from the pulse generating means to reach the detection position from the end position of the moving memberIf the motors are different, it is determined that a step-out has occurred in the pulse motor while moving the moving member in one direction or the opposite direction.And step-out detection means.
[0020]
  In the substrate processing apparatus according to the third aspect of the present invention, the moving member driven by the pulse motor moves in one direction, and the pulse detecting means applies the pulse motor to the pulse motor while the detected member moves from the detection position to the end point position. By determining the number of drive pulses that are applied and the number of drive pulses applied to the pulse motor from the pulse generation means until the detected member reaches the detection means from the end point position when the moving member moves in the opposite direction, The presence or absence of a difference between the amount of rotation of the pulse motor corresponding to the number of drive pulses given to the pulse motor and the amount of rotation of the actual pulse motor is detected.While moving the moving member in one direction or in the opposite directionThe presence / absence of a step-out of the pulse motor can be detected. Therefore, it is possible to detect the step-out of the pulse motor without providing an encoder in the pulse motor, the structure of the substrate processing apparatus can be simplified, and the enlargement of the apparatus can be suppressed.
[0021]
  A substrate processing apparatus according to a fourth aspect of the present invention is the configuration of the substrate processing apparatus according to the third aspect, wherein the detected member moves from the detection position to the end position when the step-out detection means moves in one direction of the moving member. During this time, the number of drive pulses given from the pulse generating means to the pulse motor is counted as the first pulse number, and the number of pulses until the detected member reaches the detection position from the end point position when the moving member moves in the reverse direction is counted. When the counting means for counting the number of drive pulses given from the generating means to the pulse motor as the second pulse number and the first pulse number obtained by the counting means and the second pulse number are different, the pulse motor A step-out occurredWhenIt has the determination means to determine, It is characterized by the above-mentioned.
[0022]
In this case, the determining means is based on whether or not there is a difference between the number of driving pulses counted when the moving member moves in one direction and the number of driving pulses counted when moving in the reverse direction. However, it is possible to easily determine whether or not the pulse motor is out of step.
[0023]
  A substrate processing apparatus according to a fifth aspect of the present invention is a substrate processing apparatus that performs a predetermined process on a substrate, and performs a predetermined process on the substrate holding unit that holds the substrate and the substrate held on the substrate holding unit. A processing unit, a moving member provided so as to be movable in relation to processing in the processing unit, a pulse motor for moving the moving member, a pulse generating means for providing a driving pulse to the pulse motor, and a moving member, Provided at the detection member that moves within a predetermined range defined by the movement start position and the movement end position together with the movement member, and at the detection position that is located between the movement start position and the movement end position. Detection means, and when the moving member moves, the detected member should be given to the pulse motor from the pulse generating means required for movement between the movement start position and the detection position or between the detection position and the movement end position. And Luz number, the detected member is required to move between the movement end position with the detection position or between the detection position and the movement start position actually when moving the moving memberPaBased on the number of drive pulses given to the pulse motor from the pulse generating means.While moving the moving memberAnd a step-out detecting means for detecting step-out of the pulse motor.Is.
[0024]
  In the substrate processing apparatus according to the fifth aspect of the invention, when the moving member driven by the pulse motor moves, the drive to be given to the pulse motor from the pulse generating means required for the detection member to move between the movement start position and the detection position. Based on the number of pulses and the number of drive pulses applied to the pulse motor from the pulse generating means required for the detected member to move between the movement start position and the detection position when the moving member is actually moved, the pulse motor is applied to the pulse motor. The presence / absence of a difference between the amount of rotation of the pulse motor corresponding to the number of drive pulses and the amount of rotation of the actual pulse motor can be detected, whereby the presence / absence of step-out of the pulse motor can be detected. Alternatively, when the moving member driven by the pulse motor moves, the number of driving pulses to be given to the pulse motor from the pulse generating means required for the detected member to move between the detection position and the movement end position, and the actual number of the moving member A pulse motor according to the number of drive pulses applied to the pulse motor based on the number of drive pulses applied to the pulse motor from the pulse generating means required for the detected member to move between the detection position and the movement end position during movement Detects whether there is a difference between the amount of rotation and the amount of actual pulse motor rotation,While moving the moving memberThe presence / absence of a step-out of the pulse motor can be detected. Therefore, it is possible to detect the step-out of the pulse motor without providing an encoder in the pulse motor, the structure of the substrate processing apparatus can be simplified, and the enlargement of the apparatus can be suppressed.
[0025]
A substrate processing apparatus according to a sixth aspect of the present invention is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the processing unit performs processing from a nozzle for discharging a processing liquid to the substrate and a processing liquid supply source. A pump that sucks the liquid and discharges the sucked processing liquid to the nozzle, and the moving member is provided so as to be movable in one direction or the reverse direction to operate the pump.
[0026]
In this case, the step-out detection means detects the occurrence of step-out of the pulse motor that drives the pump via the moving member, thereby quickly detecting the occurrence of processing liquid discharge failure from the nozzle and expanding the processing failure. Can be prevented.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram showing a configuration of a rotary coating apparatus according to a first embodiment of the present invention. In FIG. 1, the rotary coating apparatus includes a spin motor 1 and a substrate holding unit 2 that is attached to the tip of the rotation shaft of the spin motor 1 and is driven to rotate while holding the substrate W in a horizontal posture. Further, the rotary coating apparatus has a resist solution supply system 3 for supplying a resist solution to the substrate W.
[0028]
The resist solution supply system 3 includes a resist container 8 that stores the resist solution 9, a resist nozzle 4 that discharges the resist solution 9, resist supply pipes 5 a and 5 b that connect the resist nozzle 4 and the resist container 8, and resist supply A discharge pump 6 and a pump drive motor 7 disposed between the pipes 5a and 5b are provided.
[0029]
The resist nozzle 4 is formed to be movable between an upper position of the substrate W and a standby position outside the substrate W, and discharges the resist liquid 9 onto the surface of the substrate W.
[0030]
FIG. 2 is a schematic cross-sectional view of a discharge pump provided with a pump drive motor. The discharge pump 6 includes a pump unit 6a that discharges a resist solution and a cylinder unit 6b that applies a discharge pressure to the resist solution of the pump unit 6a. Further, a pump drive motor 7 is connected to the cylinder portion 6b. The pump part 6a of the discharge pump 6 is disposed adjacent to the cylinder part 6b, and the pump drive motor 7 is disposed adjacent to the cylinder part 6b opposite to the pump part 6a of the discharge pump 6.
[0031]
The cylinder body 29 of the cylinder portion 6 b is supported above the base 20 by the bracket 21 and the support column 22. A pressure space 30 is formed inside the cylinder body 29, and an expandable / contractible bellows 28 is disposed inside the pressure space 30. A lifting shaft 27 is attached inside the bellows 28. The upper end of the elevating shaft 27 is fixed to the inside of the bellows 28, and the lower end extends through the lower part of the cylinder body 29 and extends downward. A screw portion 27a is formed at the lower end portion of the elevating shaft 27, and the ball screw 26 is screwed to the screw portion 27a. The ball screw 26 is rotatably attached to the base 20, and a pulley 24 is attached to the lower side of the base 20 on the same axis as the ball screw 26.
[0032]
The pump drive motor 7 is fixed to the base 20, and a pulley 23 is attached to the rotating shaft of the pump drive motor 7 below the base 20. A pulley 23 attached to the rotating shaft of the pump drive motor 7, a ball screw 26 and a coaxial pulley 24 are connected by a timing belt 25.
[0033]
The pump part 6 a of the discharge pump 6 has a hollow pump chamber 33 inside the pump body 32. The pump body 32 is connected to the cylinder body 29 of the cylinder portion 6 b and has a communication hole 34 that communicates with the communication hole 31 of the cylinder body 29. The communication hole 34 communicates with the pump chamber 33.
[0034]
Inside the pump chamber 33, a hollow cylindrical tube 35 having elasticity is arranged. Between the cylindrical tube 35 and the pump chamber 33, an oily fluid supplied from the cylinder portion 6b is filled. A suction-side resist supply pipe 5b is connected to the lower end of the cylindrical tube 35 via a check valve 37, and a discharge-side resist supply pipe 5a is connected to the upper end of the cylindrical tube 35 via a check valve 36. Is connected. Further, a resist solution passage is formed inside the cylindrical tube 35.
[0035]
The check valve 37 at the lower end of the cylindrical tube 35 allows the resist solution to flow into the cylindrical tube 35 from the resist supply tube 5b side, and the resist solution flows back from the inside of the cylindrical tube 35 to the resist supply tube 5b side. Is prohibited. The check valve 36 above the cylindrical tube 35 allows the resist solution inside the cylindrical tube 35 to flow out to the resist supply tube 5a side, and the resist solution from the resist supply tube 5a side to the inside of the cylindrical tube 35. Is prohibited from flowing back.
[0036]
Further, the discharge pump 6 includes a sector 41 fixed to the lifting shaft 27 and a home sensor 40 that detects the movement of the sector 41. The home sensor 40 and the sector 41 are used for an origin return operation and a step-out detection operation of the pump drive motor 7 which will be described later.
[0037]
The pump drive motor 7 is composed of a pulse motor, and is driven forward and reverse by a drive pulse output from the motor controller 10. The motor controller 10 includes a pulse generator 10 a that generates a drive pulse for driving the pump drive motor 7 and a count unit 10 b that counts the number of drive pulses applied to the pump drive motor 7.
[0038]
The main controller 11 controls the operation of each part of the rotary coating apparatus according to a predetermined processing procedure, and outputs a control signal to the motor controller 10 to control the rotation operation of the pump drive motor 7.
[0039]
In this embodiment, the substrate holding unit 2 corresponds to the substrate holding unit of the present invention, the resist nozzle 4, the discharge pump 6, and the resist supply pipes 5a and 5b correspond to the processing unit, and the lifting shaft 27 corresponds to the moving member. The pump drive motor 7 corresponds to the pulse motor, the pulse generator 10a of the motor controller 10 corresponds to the pulse generator, the count unit 10b corresponds to the counter, the sector 41 corresponds to the detected member, and the home The sensor 40 corresponds to detection means, and the motor controller 10 and the main controller 11 correspond to step-out detection means.
[0040]
Here, the discharge operation of the resist solution in the rotary coating apparatus having the above configuration will be described. The discharge pump 6 performs an operation in which a discharge process for discharging a predetermined amount of resist liquid and a suction process for sucking and replenishing the same amount of resist liquid as the discharged resist liquid from the resist container 8 are performed as one cycle.
[0041]
In FIG. 1 and FIG. 2, in the resist solution discharging step, a drive pulse for normal rotation is given from the motor controller 10 to the pump drive motor 7. When the pump drive motor 7 rotates in the forward direction, the pulley 23, the timing belt 25, and the pulley 24 are rotated in the forward direction, whereby the ball screw 26 rotates in the forward direction. And the raising / lowering axis | shaft 27 screwed together with the ball screw 26 raises, and extends the bellows 28 upwards. When the bellows 28 is extended, the pressure space 30 is compressed. An oily fluid is sealed in the pressurizing space 30, and the bellows 28 compresses the pressurizing space 30, so that the oily fluid passes through the communication hole 31 provided in the cylinder body 29, and the pump chamber 33 of the pump unit 6 a. Move to.
[0042]
When the oily fluid is pressed into the pump chamber 33, the cylindrical tube 35 is compressed. As a result, an amount of resist liquid corresponding to the compression amount of the cylindrical tube 35 is discharged from the resist nozzle 4 to the substrate W through the resist supply pipe 5a.
[0043]
In the resist solution suction step, a reverse drive pulse is applied from the motor controller 10 to the pump drive motor 7. When the pump drive motor 7 rotates in the reverse direction, the pulley 23, the timing belt 25, and the pulley 24 are rotated in the reverse direction, and the ball screw 26 is rotated in the reverse direction. And the raising / lowering axis | shaft 27 screwed together with the ball screw 26 descend | falls and the bellows 28 is retracted below. When the bellows 28 is retracted, the pressurized space 30 is expanded and decompressed, and the oily fluid in the pump chamber 33 is sucked into the pressurized space 30.
[0044]
When the oily fluid in the pump chamber 33 is sucked back into the pressurized space 30 of the cylinder portion 6b, the pressure in the pump chamber 33 is reduced and the cylindrical tube 35 expands. Then, an amount of resist solution corresponding to the amount of expansion of the cylindrical tube 35 is sucked into the cylindrical tube 35 from the resist supply tube 5b on the suction side.
[0045]
In this way, by applying a drive pulse from the motor controller 10 and rotating the pump drive motor 7 forward and backward, the bellows 28 of the cylinder portion 6b is expanded and contracted, and the oily fluid in the pressurized space 30 is sent to the pump portion 6a side. Further, the resist solution is discharged from the discharge pump 6 by sucking from the pump unit 6 a, and the resist solution is sucked into the discharge pump 6 from the resist container 8.
[0046]
In the rotary coating apparatus, it is necessary to accurately control the amount of the resist solution discharged from the resist nozzle 4. As described above, the amount of resist solution discharged from the discharge pump 6 is defined by the amount of movement of the bellows 28 of the cylinder portion 6 b, and the amount of movement of the bellows 28 is defined by the amount of rotation of the pump drive motor 7. The rotation amount of the pump drive motor 7 is controlled by the number of drive pulses output from the pulse generator 10 a of the motor controller 10. For this reason, when the operation state of the pump drive motor 7 is normal, the pump drive motor 7 rotates in accordance with the number of drive pulses from the motor controller 10, and the bellows 28 moves in response to the rotation from the discharge pump 6. A fixed amount of resist solution is discharged to the substrate W through the resist nozzle 4.
[0047]
However, in the pump drive motor 7, a state where the pump drive motor 7 does not rotate by an amount corresponding to a given number of drive pulses, that is, a step-out may occur. When stepping out occurs in the pump drive motor 7, the discharge amount of the resist solution from the resist nozzle 4 is different from a desired amount, and defects such as non-uniform film thickness occur in the resist thin film formed on the surface of the substrate W. .
[0048]
Therefore, in the conventional rotary coating apparatus, the pump drive motor 7 is provided with an encoder to detect the presence of step-out. On the other hand, in the rotary coating apparatus of the present embodiment, the encoder is omitted in order to suppress an increase in the size of the rotary coating apparatus. In this embodiment, therefore, the out-of-step detection of the pump drive motor 7 is detected by the following method using the sector 41 fixed to the lifting shaft 27 of the discharge pump 6 and the home sensor 40 that detects the passage of the sector 41. Do.
[0049]
FIG. 3 is an explanatory view showing the movement state of the sector during the operation of the discharge pump. In FIG. 3, the X axis indicates the moving direction of the sector 41 corresponding to the lifting direction of the lifting shaft 27. In the X axis, MO indicates a mechanical limit position at which the sector 41 can move in the direction of the origin, O indicates the origin position of the sector 41, and S indicates the detection position of the home sensor 40. Further, X1 and X2 indicate the end point position of the sector 41 when the discharge of the discharge pump 6 is finished.
[0050]
3A shows a movement state of the sector 41 when the pump drive motor 7 is returned to the origin, FIG. 3B shows a movement state of the sector 41 when the pump drive motor 7 is normally operated, FIG. 3C shows a movement state of the sector 41 when the pump drive motor 7 is stepped out. In the following description, the motor controller 10 applies 4000 forward drive pulses to the pulse drive motor 7 to discharge 2 ml (milliliter) of the resist solution from the discharge pump 6, and then 4000 reverse drive pulses. An example in which 2 ml of resist solution is sucked from the resist container 8 by being applied to the pulse drive motor 7 will be described.
[0051]
(1) Return to origin operation
As an initial setting of the discharge pump 6, it is necessary to return the pump drive motor 7 to the origin position when the power is turned on. Therefore, as shown in FIG. 3 (a), a forward rotation drive pulse having a pulse number N1 (hundreds of pulses) is given to the pump drive motor 7 to temporarily move the sector 41 in the positive direction of the X axis, and then reverse rotation is performed. A drive pulse is applied to move the sector 41 in the negative direction of the X axis. When the home sensor 40 detects the sector 41, the count unit 10b of the motor controller 10 starts counting the number of drive pulses applied to the pump drive motor 7 using the detection signal of the home sensor 40 as a trigger. The origin position O of the pump drive motor 7 is set to a position returned from the detection position S of the home sensor 40 by a predetermined number of pulses N2 (for example, 600 pulses) in the negative direction of the X axis. Therefore, when the drive pulse count reaches the predetermined value N2, the movement of the sector 41 is stopped. As a result, the sector 41 stops at the origin position O of the pump drive motor 7.
[0052]
(2) Normal discharge operation
As shown in FIG. 3B, in the resist solution discharge process, the pulse generator 10a of the motor controller 10 is in a state where the sector 41 attached to the lifting shaft 27 of the discharge pump 6 is located at the origin position O. A drive pulse having a pulse number N3 (4000 pulses) corresponding to the discharge amount of the resist solution is applied to the pump drive motor 7, and the pump drive motor 7 rotates forward. As a result, the sector 41 moves to the normal end point position X1 corresponding to the drive pulse. The bellows 28 moves in accordance with the distance that the sector 41 moves from the origin position O to the normal end point position X1, whereby a predetermined amount (2 ml) of resist solution is discharged from the discharge pump 6.
[0053]
In the resist solution suction step, the pulse generator 10a of the motor controller 10 gives the drive pulses of the opposite phase to the pump drive motor 7 with the same number of pulses N4 (4000 pulses) as in the resist discharge step. The pump drive motor 7 reverses according to the applied drive pulse. As a result, the sector 41 moves from the normal end position X1 to the origin position O. During this time, the bellows 28 is degenerated, whereby a predetermined amount (2 ml) of the resist solution is sucked from the resist container 8 into the cylindrical tube 35 of the pump unit 6a.
[0054]
(3) Operation at the time of step-out of the pump drive motor 7
The step-out of the pump drive motor 7 often occurs in one of the resist solution discharge process and the suction process. In addition, the step-out of the pump drive motor 7 in the discharge process is particularly problematic because it causes a shortage of the resist solution discharge amount.
[0055]
As shown in FIG. 3C, when stepping out occurs in the pump drive motor 7 in the resist solution discharge process, the drive is performed with the same number of pulses N3 (4000 pulses) as in the normal operation shown in FIG. Although a pulse is given to the pump drive motor 7, the pump drive motor 7 does not move by the given number of drive pulses, and the sector 41 stops at the end point position X2 before the normal end point position X1. This end point position X2 corresponds to a driving pulse having a pulse number N30 smaller than the normal pulse number N3.
[0056]
Further, in the resist solution suction process, the sector 41 moves from the end point position X2 toward the origin position O side in accordance with the number N4 (4000 pulses) of the reverse drive pulses given from the motor controller 10. This pulse number N4 corresponds to the distance that the sector 41 moves from the normal end position X1 to the origin position O. For this reason, the sector 41 that has started to move from the end point position X2 passes through the origin position O, possibly reaches the machine origin position MO, and the movement is forcibly stopped. In this case, although the movement of the sector 41 is stopped and the rotation of the pump drive motor 7 is physically stopped, the drive pulse is continuously given from the motor controller 10, so that the pump drive motor 7 or the like fails. This is not preferable.
[0057]
In the present embodiment, the out-of-step detection is performed by the following method with respect to the occurrence of the out-of-step of the pump drive motor 7. FIG. 4 is an explanatory diagram showing the movement state of the sector during the step-out detection operation.
[0058]
(4) First step-out detection method
In the first step-out detection method, after the sector 41 reaches the detection position of the home sensor 40 in the resist solution suction step, the number of drive pulses applied to the pump drive motor 7 is counted until the sector 41 stops. Is the method. This step-out detection operation is performed simultaneously with the normal resist solution suction operation shown in (2) above.
[0059]
As shown in FIG. 4A, the origin position O of the sector 41 is set away from the detection position S of the home sensor 40 by a distance corresponding to a certain number of pulses N2 (for example, 600 pulses). Therefore, when the resist solution is sucked, the sector 41 reaches the detection position S of the home sensor 40, and the signal that the home sensor 40 detects the sector 41 is used as a trigger. The number of drive pulses NX output to the pump drive motor 7 from the detection position S until the actual stop is counted. The count unit 10b of the motor controller 10 counts the number N2 of drive pulses applied to the pump drive motor 7 while the sector 41 moves from the origin position O to the detection position S in the resist solution ejection process. Yes.
[0060]
The main controller 11 receives the pulse number N2 and the pulse number NX from the count unit 10b of the motor controller 10, and compares the two. If they match, the pump drive motor 7 has not stepped out. If they are different, it is determined that the pump drive motor 7 has stepped out. Thereby, the presence or absence of step-out of the pump drive motor 7 can be detected.
[0061]
(5) Second step-out detection method
In the second step-out detection method, in the resist solution suction step, the pump drive motor 7 performs an origin return operation to forcibly return the sector 41 to the origin position O, and the sector 41 returns to the origin position O. In this case, the number of drive pulses given to the pump drive motor 7 is detected to detect the presence of step-out.
[0062]
As shown in FIG. 4B, when a step-out occurs in the pump drive motor 7 in the resist solution discharge process, a drive pulse having a regular number of pulses N3 is supplied from the pulse generator 10a of the motor controller 10 to the pump drive motor 7. However, the sector 41 moves only to the end point position X2 corresponding to the pulse number N30 smaller than the normal pulse number N3.
[0063]
In this resist solution ejection process, when the sector 41 reaches the detection position S and the home sensor 40 detects the sector 41, the motor controller 10 receives the detection signal of the sector 41 from the home sensor 40. Then, the count unit 10b of the motor controller 10 starts counting drive pulses output from the motor controller 10 to the pump drive motor 7, and when the sector 41 moves from the detection position S to the end point position X2, the pump drive motor The total number of drive pulses N50 given to 7 is counted.
[0064]
In the resist solution suction step, the main controller 11 causes the pump drive motor 7 to perform an origin return operation. In the origin return operation, a reverse drive pulse is given to the pump drive motor 7. Then, when the sector 41 reaches the detection position S of the home sensor 40 from the end point position X2, and the home sensor 40 detects the sector 41, the motor controller 10 receives the detection signal of the sector 41 from the home sensor 40, and then A drive pulse having the number of pulses N2 (for example, 600 pulses) necessary to move the sector 41 from the detection position S of the home sensor 40 to the origin position O is output to the pump drive motor 7. As a result, the pump drive motor 7 stops after rotating until the sector 41 reaches the origin position O.
[0065]
The count unit 10b of the motor controller 10 receives the total number N40 of drive pulses given to the pump drive motor 7 when the sector 41 moves from the end point position X2 to the detection position S during the origin return operation of the pump drive motor 7. Count. The main controller 11 is given to the pump drive motor 7 when the total number N50 of drive pulses given from the motor controller 10 to the pump drive motor 7 in the resist discharge process of the discharge pump 6 and when the pump drive motor 7 returns to the origin. The total number of drive pulses N40 is compared. If the two values are equal, the step-out of the pump drive motor 7 has not occurred, and if the two values are different, it is determined that the step-out of the pump drive motor 7 has occurred. Thereby, the presence or absence of step-out of the pump drive motor 7 can be detected.
[0066]
FIG. 5 is a schematic diagram showing a schematic configuration of a substrate cleaning apparatus according to a second embodiment of the present invention, and FIG. 6 is a schematic plan view of the substrate cleaning apparatus of FIG. In this second embodiment, the step-out detection mechanism used in the rotary coating apparatus according to the first embodiment is applied to the moving mechanism of the cleaning liquid nozzle of the substrate cleaning apparatus.
[0067]
5 and 6, the substrate cleaning apparatus includes a spin motor 51 and a substrate holder 52 that is attached to the tip of the rotation shaft of the spin motor 51 and is driven to rotate while holding the substrate W in a horizontal posture. A hollow cup 53 is provided around the substrate holding part 52 to prevent the cleaning liquid or the like from splashing outside.
[0068]
A cleaning liquid nozzle 54 that is movable in the horizontal direction and the vertical direction is disposed above the substrate W held by the substrate holder 2. The cleaning liquid nozzle 54 is attached to the tip of the support arm 55. The base 55 a of the support arm 55 is attached to the rotation shaft 57 of the rotary motor 56. Accordingly, the cleaning liquid nozzle 54 and the support arm 55 can be rotated in a horizontal plane around the rotation shaft 57 of the rotary motor 56.
[0069]
Further, the rotary motor 56 is attached to the lift base 58, and the lift base 58 is screwed into a ball screw 59 connected to the rotary shaft of the lift motor 60. Accordingly, the cleaning liquid nozzle 54 and the support arm 55 can be moved up and down by the rotation of the lifting motor 60.
[0070]
The spin motor 51, the rotation motor 56, and the lifting motor 60 are controlled by a motor controller 63. An encoder 65 is attached to the lift motor 60, and the motor controller 63 controls the rotation operation of the lift motor 60 based on a detection signal from the encoder 65.
[0071]
A sector 61 is attached to the support arm 55, and a home sensor 62 for detecting the return of the sector 61 to the standby position is disposed inside the standby pot 64. A detection signal from the home sensor 62 is output to the motor controller 63.
[0072]
In the substrate cleaning apparatus having the above structure, the cleaning liquid nozzle 54 rotates in the horizontal direction from the standby position in the standby pot 64 during the substrate cleaning process. Then, while passing over the substrate W, a cleaning liquid to which ultrasonic vibration is applied is supplied from the cleaning liquid nozzle 54 to the surface of the substrate W to clean the surface of the substrate W. In this substrate cleaning process, the rotation range of the cleaning nozzle 54 in the horizontal direction is regulated so that the cleaning liquid is evenly supplied to the surface of the substrate W.
[0073]
Therefore, in this substrate cleaning apparatus, the out-of-step detection of the rotary motor 56 that rotates the cleaning liquid nozzle 54 is performed using the sector 61 and the home sensor 62. Note that the out-of-step detection operation in this substrate cleaning apparatus can apply the same method as the out-of-step detection operation in the rotary coating apparatus of the first embodiment. That is, the rotary motor 56 in the second embodiment corresponds to the pump drive motor 7 in the first embodiment, the motor controller 63 corresponds to the motor controller 10, and the main controller 66 corresponds to the main controller 11.
[0074]
In this embodiment, the cleaning liquid nozzle 54 corresponds to the processing section of the present invention, and the support arm 55 corresponds to the moving member.
[0075]
In the substrate cleaning apparatus according to the second embodiment, by omitting the encoder that detects the rotational operation of the rotary motor 56, the structure near the rotary motor 56 that rotates the cleaning liquid nozzle 54 and the support arm 55 is simplified, and the substrate is cleaned. The entire cleaning apparatus can be reduced in size.
[0076]
In the first and second embodiments, the rotary coating apparatus and the substrate cleaning apparatus have been described as examples of the substrate processing apparatus. However, the present invention is not limited to these, and the pulse motor is unidirectional or reverse. The step-out detection means of the present invention can be applied to other substrate processing apparatuses having members driven in the direction and detecting and controlling the rotational operation of the pulse motor.
[0077]
In the first out-of-step detection method and the second out-of-step detection method in the first and second embodiments, the lifting shaft 27 and the support arm 55 corresponding to the moving member are reciprocated so as to be detected members. The number of drive pulses actually given to move the sectors 41 and 61 from the origin position to the detection position on the forward path, and the number of drive pulses actually given to move from the detection position to the origin position on the return path , The presence or absence of step-out of the pulse motor is detected, but the present invention is not limited to this. For example, a detected member that moves in a predetermined range defined by a movement start position and a movement end position together with the moving member moves between the movement start position and the detection position or between the detection position and the movement end position as the movement member moves. If the number of pulses to be given to the pulse motor required for the movement in between is known in advance, the number of pulses and the detected member when the moving member is actually moved are between the movement start position and the detection position or the detection The presence / absence of step-out of the pulse motor may be detected based on the position and the number of drive pulses applied to the pulse motor required for movement between the movement end positions. In this case, it is not necessary to count the number of drive pulses over the reciprocation of the movement of the moving member.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the configuration of a rotary coating apparatus according to a first embodiment of the present invention.
FIG. 2 is a schematic sectional view of a discharge pump provided with a pump drive motor.
FIG. 3 is an explanatory diagram showing a movement state of a sector during operation of a discharge pump.
FIG. 4 is an explanatory diagram showing a sector movement state during a step-out detection operation;
FIG. 5 is a schematic diagram showing a configuration of a substrate cleaning apparatus according to a second embodiment of the present invention.
6 is a plan view of the substrate cleaning apparatus of FIG. 5. FIG.
FIG. 7 is a schematic diagram showing a configuration of a conventional rotary coating apparatus.
[Explanation of symbols]
1,51 Spin motor
2,52 Substrate holder
3 Resist solution supply system
4 resist nozzle
6 Discharge pump
6a Cylinder part of discharge pump
6b Pump part of the discharge pump
7 Pump drive motor
10, 63 Motor controller
10a Pulse generator
10b Count unit
11, 66 Main controller
26 Ball screw
27 Lifting shaft
28 Bellows
30 Pressurized space
31, 34 communication hole
33 Pump room
35 Cylindrical tube
40,62 Home sensor
41, 61 sectors
54 Cleaning liquid nozzle
55 Support arm
56 Rotating motor

Claims (6)

A substrate processing apparatus for performing predetermined processing on a substrate,
A substrate holder for holding the substrate;
A processing unit that performs a predetermined process on the substrate held by the substrate holding unit;
A movable member movably provided in connection with the processing in the processing unit;
A pulse motor for moving the moving member in one direction or in the opposite direction;
Pulse generating means for providing a driving pulse to the pulse motor;
A detected member that is provided in the moving member and reciprocates between an origin position and an end point position as the moving member moves in one direction or in the opposite direction;
Detection means provided at a detection position that is a fixed distance away from the origin position toward the end point position, and detecting that the moving member has reached the detection position;
During the movement of the moving member in one direction, the number of drive pulses given from the pulse generating means to the pulse motor while the detected member moves from the origin position to the detection position, and the reverse direction of the moving member When the number of drive pulses applied from the pulse generating means to the pulse motor is different from when the detected member reaches the detection position and stops when moving to A substrate processing apparatus comprising: step-out detection means for determining that step-out has occurred in the pulse motor during movement in the direction . The step-out detection means includes
The number of drive pulses applied from the pulse generation means to the pulse motor while the detected member moves from the origin position to the detection position when the moving member moves in one direction is counted as a first pulse number. Then, when the moving member moves in the reverse direction, the number of drive pulses given to the pulse motor from the pulse generating means until the detected member reaches the detection position and then stops is determined as a second pulse. Counting means for counting as numbers,
2. A determination means for determining that a step-out has occurred in the pulse motor when the first pulse number obtained by the counting means is different from the second pulse number. The substrate processing apparatus as described. A substrate processing apparatus for performing predetermined processing on a substrate,
A substrate holder for holding the substrate;
A processing unit that performs a predetermined process on the substrate held by the substrate holding unit;
A movable member movably provided in connection with the processing in the processing unit;
A pulse motor for moving the moving member in one direction or in the opposite direction;
Pulse generating means for providing a driving pulse to the pulse motor;
A detected member that is provided in the moving member and reciprocates between an origin position and an end point position as the moving member moves in one direction or in the opposite direction;
Detection means provided at a detection position that is a fixed distance away from the origin position toward the end point position, and detecting that the moving member has reached the detection position;
The number of drive pulses given from the pulse generating means to the pulse motor while the detected member moves from the detection position to the end position when the moving member moves in one direction, and the reverse direction of the moving member When the number of drive pulses applied from the pulse generation means to the pulse motor before the detected member reaches the detected position from the end point position during the movement to the position is different or reverse A substrate processing apparatus comprising: step-out detection means for determining that step-out has occurred in the pulse motor during movement in the direction . The step-out detection means determines the number of drive pulses applied from the pulse generation means to the pulse motor while the detected member moves from the detection position to the end position when the movement member moves in one direction. A driving pulse that is counted as the first pulse number and is given to the pulse motor from the pulse generating means until the detected member reaches the detection position from the end point position when the moving member moves in the reverse direction. Counting means for counting the number of the second pulses as a second pulse number;
4. A determination means for determining that a step-out has occurred in the pulse motor when the first pulse number obtained by the counting means is different from the second pulse number. The substrate processing apparatus as described. A substrate processing apparatus for performing predetermined processing on a substrate,
A substrate holder for holding the substrate;
A processing unit that performs a predetermined process on the substrate held by the substrate holding unit;
A movable member movably provided in connection with the processing in the processing unit;
A pulse motor for moving the moving member;
Pulse generating means for providing a driving pulse to the pulse motor;
A detected member that is provided in the moving member and moves together with the moving member within a predetermined range defined by a movement start position and a movement end position;
A detection means provided at a detection position located between the movement start position and the movement end position, and detecting the arrival of the detected member;
The number of pulses to be given to the pulse motor from the pulse generating means required for the detection member to move between the movement start position and the detection position or between the detection position and the movement end position when the movement member moves. The drive given to the pulse motor from the pulse generating means required for the detected member to move between the movement start position and the detection position or between the detection position and the movement end position when the moving member is actually moved A substrate processing apparatus, comprising: a step-out detecting means for detecting whether or not the pulse motor has stepped out during movement of the moving member based on the number of pulses. The processor is
A nozzle for discharging a processing liquid onto the substrate;
A pump that sucks the processing liquid from the processing liquid supply source and discharges the sucked processing liquid to the nozzle;
The substrate processing apparatus according to claim 1, wherein the moving member is provided so as to be movable in one direction or the reverse direction in order to operate the pump.

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