JP2010239014A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of reducing a rinsing processing time and reducing a use amount of a rinsing liquid.
A substrate processing apparatus that performs processing with a first processing liquid and then with a second processing liquid includes an upper nozzle body 51 that supplies the first and second processing liquids toward the semiconductor wafer, and a slant. Detected by the rectangular nozzle body 71, film thickness detecting means 81 and 82 capable of detecting the film thickness of the upper surface of the semiconductor wafer W, a database 90 storing information such as processing liquids and processing characteristics, and the film thickness detecting means. A control device 7 for determining whether or not the liquid film on the semiconductor wafer W has been replaced from the first processing liquid to the second processing liquid based on the film thickness and the information stored in the database 90; It is set as the structure provided with.
[Selection] Figure 2

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for processing a substrate with a processing liquid.

  For example, in the manufacturing process of a semiconductor device, there are a film forming process and a photo process for forming a circuit pattern on a substrate such as a disk-shaped semiconductor wafer. In these processes, a substrate is processed by using a substrate processing apparatus such as a so-called spin processing apparatus that holds and rotates a substrate on a rotary table. There is also known a substrate processing apparatus that performs substrate processing while transporting the substrate with rollers or the like without rotating the substrate.

  In the case of processing a substrate using the spin processing apparatus, for example, the substrate is processed with a processing solution such as an etching solution that is a chemical solution, and then rinsed with a rinsing solution such as pure water as the processing solution. Next, by rotating the rotary table at a high speed, a drying process for removing the cleaning liquid remaining on the substrate is performed.

  The spin processing apparatus has a processing tank as is well known, and a cup body is provided in the processing tank. In the cup body, there is provided the rotary table rotated by a drive source. The rotary table is provided with a plurality of holding members for holding the outer peripheral portion of the substrate at predetermined intervals along the circumferential direction, and the substrate is detachably held on the rotary table by these holding members.

  Therefore, the substrate can be processed by holding the substrate on the rotary table, rotating the rotary table and supplying the processing liquid to the substrate, and drying the substrate by rotating the rotary table at a high speed after processing. Can be processed.

  As processing for supplying a processing liquid and processing a substrate, chemical processing, physical processing, replacement processing, drying processing, and the like are known. For example, in the substrate rinsing process, mist droplets are supplied to the substrate, and the processing liquid on the substrate is replaced with the rinsing liquid using energy when the droplet collides with the substrate, and contaminants are removed from the substrate. Physical processing is used. A method is known in which a contaminant is removed from a substrate by this rinsing process, and then a rotating table is further rotated to discharge a treatment liquid containing the contaminant out of the substrate to dry the substrate.

  In order to prevent the generation of droplets on the surface of the substrate during the drying process after the rinsing process, in the rinsing process, the substrate is rotated at the number of rotations for forming a liquid film, and the cleaning liquid is supplied to the upper surface of the substrate. A processing apparatus and a processing method for forming a liquid film on the entire top surface of a substrate are also known (see, for example, Patent Document 1). Also known are those that control the amount of liquid supplied to the substrate.

  Furthermore, in order to suppress the atmosphere around the substrate from being caught around the peripheral edge of the substrate, there is also known a processing apparatus and a processing method for making the sponge member face the peripheral edge of the shielding plate and maintaining the space in a nitrogen gas atmosphere. (See, for example, Patent Document 2).

JP 2003-17461 A JP 2008-166574 A

  The substrate processing apparatus and the substrate processing method described above have the following problems. That is, in the rinsing process described above, the chemical solution is replaced with a rinsing liquid such as pure water. However, in order to reliably perform the rinsing process, the rinsing process is performed for a longer time. However, when the time for the rinsing process becomes longer, the amount of the rinsing liquid such as water used for the rinsing process is increased. Further, not only the rinsing liquid but also the productivity of the substrate is lowered. However, if the rinsing time is shortened, contaminants may remain on the substrate.

  Therefore, an object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of shortening the rinsing processing time.

  The present invention is a substrate processing apparatus for processing a substrate with a first processing liquid and then processing with a second processing liquid, wherein the first processing liquid supply supplies the first processing liquid onto the substrate. Means, second processing liquid supply means for supplying the second processing liquid onto the substrate supplied with the first processing liquid, and liquid on the substrate supplied with the second processing liquid. Film thickness detecting means for detecting a film thickness (film thickness), and whether or not the first processing liquid supplied to the substrate is replaced with the second processing liquid based on the detection by the film thickness detecting means. And a control unit having a determination unit for determining whether or not the substrate processing apparatus is provided.

  A drying means for drying the liquid film on the substrate supplied with the second treatment liquid; and a storage means for storing a drying characteristic at the time of drying of the second treatment liquid. And means for drying characteristics of the film thickness of the liquid film based on detection by the film thickness detection means when the liquid film is dried by the drying means, and the second processing liquid stored in the storage means. It is preferable to determine whether or not the first treatment liquid has been replaced with the second treatment liquid by comparing the characteristics during drying.

  Storage means storing characteristics of the second processing liquid, and the control means is supplied with the second processing liquid on the substrate by the second processing liquid supply means. Sometimes, the characteristics of the liquid film on the substrate are predicted based on the detection of the film thickness detection means, and the predicted characteristics of the second processing liquid and the second characteristics stored in the storage means It is preferable to determine whether or not the first treatment liquid is replaced with the second treatment liquid by comparing the characteristics of the treatment liquid.

  The control means causes the second processing liquid supply means to further supply the second processing liquid onto the substrate when the first processing liquid is not replaced with the second processing liquid. It is preferable.

  The present invention is a substrate processing method of processing a substrate with a first processing liquid and then processing with a second processing liquid, the step of supplying the first processing liquid onto the substrate, and the first Supplying the second processing liquid onto the substrate supplied with the processing liquid, detecting the film thickness of the liquid film on the substrate supplied with the second processing liquid, and the film And determining whether or not the first processing liquid supplied to the substrate is replaced with the second processing liquid based on thickness detection. .

  A step of drying the liquid film on the substrate supplied with the second treatment liquid, and the drying characteristics of the liquid film detected when the liquid film is dried, and the second It is preferable to determine whether or not the first treatment liquid has been replaced with the second treatment liquid by comparing the drying characteristics of the treatment liquid during drying.

  Predicting the characteristics of the liquid film from the detected liquid film thickness on the substrate when the second processing liquid is supplied onto the substrate by the second processing liquid supply means; And comparing the predicted characteristics of the liquid film with the characteristics of the second processing liquid to determine whether the first processing liquid has been replaced with the second processing liquid. It is preferable to determine.

  In the case where the first processing liquid is not replaced with the second processing liquid, it is preferable to further include a step of further supplying the second processing liquid onto the substrate.

  According to this invention, the confirmation of the replacement state in the rinsing process and the drying process, and the rinsing process and the drying process a plurality of times can reduce the rinsing process time and the amount of the rinsing liquid used. Thereby, the productivity of the semiconductor wafer W can be improved.

Explanatory drawing which shows typically the structure of the processing apparatus using the substrate processing tank which concerns on one embodiment of this invention. Sectional drawing which shows the structure of the same substrate processing tank. Explanatory drawing which shows an example of the relationship between the residual process liquid amount of the process liquid used for the substrate processing tank, and rinse time. Explanatory drawing which shows an example of the relationship between the film thickness on the board | substrate of the process liquid and rinse liquid used for the substrate processing tank, and drying time. The flowchart which shows an example of the flow of the rinse process in the same substrate processing tank, and a drying process. Explanatory drawing which shows an example of the relationship between the liquid film thickness on a board | substrate in the rinse process and a drying process, and time. Explanatory drawing which shows an example of the relationship between the adhesion contaminant amount of the board | substrate in the rinse process and a drying process, and time. Explanatory drawing which shows an example of the relationship between the liquid film thickness on a board | substrate in the rinse process and a drying process, and time.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a substrate processing apparatus 100. The substrate processing apparatus 100 is a processing apparatus for a single wafer type semiconductor wafer (substrate) W. The substrate processing apparatus 100 has a cassette station 101. The cassette station 101 includes a loader unit 103 in which an unprocessed semiconductor wafer W is accommodated in the cassette 102 and an unloader unit 104 that collects the rinsed semiconductor wafer W in the cassette 102 as will be described later.

  The cassette station 101 is provided with a delivery unit 105 adjacent thereto. The delivery unit 105 is provided with two substrate processing tanks 1.

  The delivery unit 105 includes a robot 106 that is driven in the X, Y, and θ directions. This robot 106 handles a semiconductor wafer W before processing and a semiconductor wafer W after processing separately, and has a pair of arms 107, and an unprocessed semiconductor wafer W accommodated in the cassette 102 of the loader unit 103 by one arm 107. Is taken out and supplied to the substrate processing tank 1. The semiconductor wafer W supplied to the substrate processing tank 1 is subjected to a cleaning process and a drying process.

  The semiconductor wafer W processed in the substrate processing tank 1 is taken out by the other arm 107 of the robot 106 and stored in the cassette 102 of the unloader unit 104 of the cassette station 101.

  When all of the semiconductor wafers W stored in the loader unit 103 are processed by the substrate processing tank 1 and stored in the unloader unit 104, the unloader unit 104 is transferred to an apparatus for performing the next process.

  Next, the substrate processing tank 1 will be described with reference to FIG. A cup body 2 is disposed in the substrate processing tank 1. The cup body 2 includes a lower cup 3 provided on the bottom plate of the substrate processing tank 1 and an upper cup 4 provided so as to be vertically movable with respect to the lower cup 3 by a vertical drive mechanism (not shown).

  A plurality of discharge pipes 5 are connected to the bottom wall of the lower cup 3 at predetermined intervals in the circumferential direction. These discharge pipes 5 communicate with an exhaust pump 6. The substrate processing tank 1 is provided with a control device (control means) 7. The exhaust pump 6 is formed such that the control device 7 can control the start and stop and the rotational speed.

  A base plate 8 is disposed on the lower surface side of the cup body 2. An attachment hole 9 is formed in the base plate 8 at a position corresponding to the lower cup 3. The upper end portion of the stator 12 of the control motor 11 constituting the driving means is fitted and fixed in the mounting hole 9. The control motor 11 is configured such that the start / stop and the number of rotations can be controlled by the control device 7.

  The stator 12 is formed in a cylindrical shape. Similarly, a cylindrical rotor 13 is rotatably inserted into the stator 12. A cylindrical connecting body 14 is integrally fixed to the upper end surface of the rotor 13 with the lower end surface in contact therewith. A flange 15 having a diameter larger than the inner diameter of the stator 12 is provided at the lower end of the connecting body 14. The flange 15 is slidably in contact with the upper end surface of the stator 12, thereby preventing the rotor 13 from falling out of the stator 12 without preventing the rotation of the rotor 13.

  A through hole 3 a is formed in the lower cup 3 at a portion corresponding to the rotor 13, and the connecting body 14 projects into the cup body 2 from the through hole 3 a. A turntable 16 is attached to the upper end of the connecting body 14. At the periphery of the turntable 16, six (two only shown) columnar holding members 17 are rotatably provided by a drive mechanism (not shown) at predetermined intervals in the circumferential direction, in this embodiment at intervals of 60 degrees. ing.

  A support pin 18 having a tapered surface is provided on the upper end surface of the holding member 17 at a position eccentric from the rotation center of the holding member 17. A semiconductor wafer W as a substrate is supplied to the turntable 16 so that the lower surface of the peripheral edge is in contact with the tapered surface of the support pin 18. If the holding member 17 is rotated in this state, the support pins 18 are eccentrically rotated, so that the semiconductor wafer W supplied to the turntable 16 is held by the support pins 18.

  The rotary table 16 is covered with a turbulent flow prevention cover 21. The turbulent flow prevention cover 21 has an outer peripheral wall 22 covering the outer peripheral surface of the rotary table 16 and an upper surface wall 23 covering the upper surface. The outer peripheral wall 22 is formed with a small diameter portion 22a on the upper side and a large diameter portion 22b on the lower side. Has been. The turbulent flow prevention cover 21 is formed to prevent turbulent flow from being generated on the upper surface of the rotary table 16 when the rotary table 16 is rotated. The upper surface of the upper cup 4 is open, and a ring-shaped member 25 is provided on the inner peripheral surface thereof.

  When the unprocessed semiconductor wafer W is supplied to the turntable 16 and when the dried semiconductor wafer W is taken out, the upper cup 4 is lowered as described later.

  An opening 31 is formed in the upper wall of the substrate processing tank 1. The opening 31 is provided with a fan / filter unit 32 such as ULPA or HEPA. The fan / filter unit 32 further cleans the air in the clean room and introduces it into the substrate processing tank 1. The amount of the clean air introduced is controlled by the control unit 7 using the drive unit 33 of the fan / filter unit 32. Control and do. That is, the drive unit 33 is configured to control the supply amount of clean air into the substrate processing tank 1 by controlling the number of rotations of a fan (not shown) of the fan / filter unit 32.

  A loading / unloading port 34 is formed on one side of the substrate processing tank 1. The entrance / exit 34 is opened and closed by a shutter 35 provided on one side of the substrate processing tank 1 so as to be slidable in the vertical direction. The shutter 35 is driven by a cylinder 36 that operates with compressed air. In other words, the cylinder 36 is provided with a control valve 37 for controlling the flow of compressed air, and the control valve 37 is controlled by the control device 7 so that the shutter 35 can be moved up and down.

  Above the semiconductor wafer W held on the turntable 16, an upper nozzle body 51 and obliquely supplying a processing liquid (first processing liquid and second processing liquid) to the upper surface of the semiconductor wafer W during each processing. A nozzle body 71 is arranged. The upper nozzle body 51 and the oblique nozzle body 71 are provided with a first processing liquid supply means and a second processing liquid supply means capable of supplying different first processing liquid and second processing liquid onto the semiconductor wafer W in each processing. Both functions of the processing liquid supply means are provided. That is, the upper nozzle body 51 and the oblique nozzle body 71 are provided so that different processing liquids can be supplied onto the semiconductor wafer W.

  The upper nozzle body 51 is attached to a first attachment member 53 provided at the tip of an arm body 52 arranged horizontally.

  The base end of the arm body 52 is connected to the upper end portion of the rotation shaft 55 arranged with the axis line vertical. The lower end of the rotation shaft 55 is connected to the output shaft 57 of the rotation drive source 56. The rotational drive source 56 is provided so that the rotational angle and rotational speed of the rotational shaft 55 can be controlled by the control device 7.

  The upper nozzle body 51 provided at the tip of the swinging arm body 52 is held by the rotary table 16 and passes from the outside on one end side in the radial direction of the semiconductor wafer W to the outside on the other end in the radial direction. It is driven to swing.

  The rocking speed, which is the moving speed of the rocking locus of the upper nozzle body 51, is controlled to gradually increase when going from the peripheral part of the semiconductor wafer W to the central part and gradually decelerate when going from the central part to the peripheral part. The

  The upper nozzle body 51 includes a first supply pipe 58 to which a supply source for supplying a processing liquid is connected, and a second supply pipe 59 to which a supply source for supplying a gas is connected. The upper nozzle body 51 is formed so that the processing liquid can be sprayed (supplied) onto the semiconductor wafer W by mist from the tip thereof. That is, the upper nozzle body 51 is provided so as to be able to perform physical processing on the semiconductor wafer W by supplying the mist-like processing liquid to the semiconductor wafer W and using energy when the processing liquid and the semiconductor wafer W collide. Yes.

  In the middle of the first supply pipe 58, a first electromagnetic valve 60 and an adjustment unit capable of adjusting the physical property value of the processing liquid are provided. In the middle of the first supply pipe 58, for example, a first temperature adjustment unit 61 capable of adjusting the temperature of the processing liquid and a first concentration adjustment unit 62 capable of adjusting the concentration of the processing liquid are provided as adjustment units. It has been. Such an adjustment unit is provided so that the film thickness of the liquid film of the processing liquid can be adjusted by adjusting the physical property value of the processing liquid.

  A second solenoid valve 63 and a second temperature adjustment unit 64 are provided in the middle of the second supply pipe 59. The first and second supply pipes 58 and 59 connected to the upper nozzle body 51 are provided, for example, inside the arm body 52, the rotation drive source 56, and the output shaft 57, and are connected to the upper nozzle body 51. Yes.

  The first supply pipe 58 supplies the upper nozzle body 51 with processing liquid such as pure water (hereinafter “water”), SC-1 such as hydrogen peroxide water or ammonia water, and etching liquid for removing the resist. The first electromagnetic valve 60 is connected to the control device 7, and the control device 7 is provided so that the flow path of the first supply pipe 58 can be opened and closed.

  The first temperature adjustment unit 61 is connected to the control device 7. The first temperature adjustment unit 61 uses a heater for fluid (liquid) heating formed so as to be able to adjust the temperature of the processing liquid supplied from the supply source.

  The first density adjustment unit 62 is connected to the control device 7. The first concentration adjusting unit 62 is provided so that the concentration of the processing liquid can be adjusted. Specifically, the first concentration adjustment unit 62 is connected to a plurality of supply sources that supply liquid. The first concentration adjustment unit 62 is supplied with water from any one of these supply sources and is supplied with a chemical solution for processing from another supply source. The first concentration adjusting unit 62 adjusts the concentration by mixing the water and the chemical solution at different ratios, and supplies the processing liquid to the upper nozzle body 51.

  The second supply pipe 59 supplies the nitrogen gas supplied from the supply source to the upper nozzle body 51. The second electromagnetic valve 63 is connected to the control device 7, and the control device 7 is formed so that the flow path of the second supply pipe 59 can be opened and closed.

  The second temperature adjustment unit 64 is connected to the control device 7. The second temperature adjustment unit 64 uses a heater for heating fluid (gas) formed so as to be able to adjust the temperature of nitrogen gas supplied from a supply source. The gas supplied from the supply source may not be nitrogen gas, but may be argon gas, for example.

  The oblique nozzle body 71 is attached to a second attachment member 72 provided obliquely above the semiconductor wafer W toward the main surface of the semiconductor wafer W. The second attachment member 72 is formed so that the oblique nozzle body 71 can be attached so that the oblique nozzle body 71 can eject the processing liquid toward the main surface of the semiconductor wafer W.

  The oblique nozzle body 71 includes a third supply pipe 74 to which a supply source for supplying the processing liquid is connected. The third supply pipe 74 is provided with a third electromagnetic valve 75 and an adjustment unit capable of adjusting the physical property value of the processing liquid in the middle thereof. In the middle of the third supply pipe 74, a third temperature adjustment unit 76 and a third concentration adjustment unit 77 are provided as adjustment units. The third supply pipe 74 is provided, for example, inside the second attachment member 72 and connected to the oblique nozzle body 71.

  The third supply pipe 74 is formed so as to be able to supply the oblique nozzle body 71 with processing liquid such as SC-1, resist stripping agent, etc., such as water, hydrogen peroxide solution, and ammonia water. The third electromagnetic valve 75 is connected to the control device 7, and the control device 7 is configured to open and close the flow path of the third supply pipe 74.

  The third temperature adjustment unit 76 is connected to the control device 7. The third temperature adjustment unit 76 uses a heater for fluid (liquid) heating formed so as to be capable of adjusting the temperature of the processing liquid supplied from the supply source.

  The third density adjustment unit 77 is connected to the control device 7. The third concentration adjusting unit 77 is provided so that the concentration of the processing liquid can be adjusted. Specifically, the third concentration adjustment unit 77 is connected to a plurality of supply sources that supply liquid. The third concentration adjustment unit 77 is supplied with water from one of these supply sources and is supplied with a chemical solution for processing from another supply source. The third concentration adjusting unit 77 adjusts the concentration by changing the ratio of the water and the chemical solution, and supplies the treatment liquid to the oblique nozzle body 71.

  The substrate processing tank 1 is provided with a monitor unit which is disposed above the turntable 16 and is a film thickness detecting means capable of detecting (monitoring) the film thickness of the entire liquid film on the upper surface of the semiconductor wafer W. Yes. The monitor unit includes a light source 81 that irradiates light to the semiconductor wafer W, a camera 82 that is a sensor that recognizes the light, and a control device 7.

  Note that such a monitor unit first irradiates the semiconductor wafer W with the light source 81. The light irradiated by the liquid film is reflected, and the reflected light is recognized by the camera 82. Specifically, the camera 82 recognizes the interference fringes generated by the reflection of the light irradiated by the light source 81 and the change of the liquid film. From the information recognized by the camera 82, the control device 7 monitors the liquid film on the semiconductor wafer W and detects the thickness of the liquid film as the liquid film on the semiconductor wafer W changes. As described above, the monitor unit is formed by the light source 81, the camera 82, and the control device 7 so that the thickness of the liquid film can always be detected.

  The light source 81 is connected to the control device 7 and is formed so as to be able to always irradiate light onto the upper surface of the semiconductor wafer W during processing of the semiconductor wafer W.

  The camera 82 is connected to the control device 7 and is configured to recognize reflected light reflected from the upper surface of the semiconductor wafer W and transmit information of the recognized reflected light to the control device 7.

  The control device 7 is connected to a database 90 which is a storage means. The database 90 stores information such as the liquid film thickness, the characteristics of the processing liquid used during preprocessing, the preprocessing conditions, the current characteristics of the liquid film on the semiconductor wafer W predicted from information such as the rinse liquid, and the like. Has been. This characteristic is, for example, viscosity, surface tension, temperature, viscosity and concentration. Further, the database 90 stores information such as necessary rinse processing conditions from the characteristics of each liquid film.

  An example of information stored in the database 90 will be described with reference to FIG. As shown in FIG. 3, when the rinsing process conditions such as the type and temperature of the process liquid and the number of rotations of the turntable 16 are the same as the database 90, the supply of the different process liquids A and B is stopped. The relationship of the amount of residual processing liquid over time is stored.

  As for the characteristics of the processing liquids A and B shown in FIG. 3, the processing liquid A is a processing liquid having a high viscosity, and the processing liquid B is a processing liquid having a low viscosity. Examples of these treatment liquids include high-viscosity treatment liquids such as sulfuric acid, hydrochloric acid, and organic solvents, and low-viscosity treatment liquids such as alcohol, IPA, acetone, and ammonia. Similarly, although not shown, changes in the amount of residual processing liquid in each processing liquid according to each rinsing processing condition, information on each processing liquid, and the like are also stored. As described above, the database 90 stores information such as the processing liquid, the rinsing liquid, and each processing.

  As described above, the control device 7 includes the exhaust pump 6, the control motor 11, the drive unit 33, the control valve 37, the first to third electromagnetic valves 60, 63, 75, and the first to third temperature adjustment units 61, 64. , 76, the first and third density adjustment units 62 and 77, the light source 81, the camera 82, and the database 90, respectively, are connected via signal lines S. The control device 7 is configured such that each component connected via these signal lines S can be independently controlled.

  The control device 7 is configured to be able to perform a rinsing process for replacing the liquid film on the semiconductor wafer W with a rinsing liquid and a drying process for the semiconductor wafer W. Specifically, the control device 7 replaces the treatment liquid (first treatment liquid) in the pretreatment of the rinse treatment on the semiconductor wafer W with the rinse liquid (second treatment liquid) by performing the rinse treatment. Is configured to be possible. In addition, the control device 7 is configured to be capable of performing a drying process in which the replaced rinse liquid is scattered by rotating the turntable 16 and the semiconductor wafer W is dried. That is, the controller 7 and the rotary table 16 constitute a semiconductor wafer W drying means.

  Furthermore, the control device 7 includes a determination unit 7a that determines a replacement state. With this determination unit, it is possible to determine whether or not the treatment liquid has been replaced with the rinse liquid during the rinsing process and the drying process. It is configured.

Moreover, the control apparatus 7 has the following functions as main functions.
(1) Function for predicting the characteristics of the liquid film on the semiconductor wafer W
(2) Function for setting the processing conditions of the semiconductor wafer W
(3) The function of monitoring the characteristics of the liquid film during processing of the semiconductor wafer W and optimizing the processing time
(4) Function to monitor the characteristics of the liquid film when drying the treatment liquid
In addition, the control apparatus 7 has a function other than said each function (1)-(4) suitably.

  Next, the functions (1) to (4) of the control device 7 will be described. In addition, the case where these functions (1)-(4) are used for the rinse process is demonstrated.

  The function (1) of the control device 7 detects the film thickness on the semiconductor wafer W by the monitor unit, and predicts the characteristics of the liquid film (first processing liquid) on the semiconductor wafer W from the detected film thickness. It is a function. Specifically, the control device 7 uses the light source 81 and the camera 82 to form a liquid film (first treatment liquid) that forms a liquid film on the upper surface of the semiconductor wafer W during the treatment of the semiconductor wafer W during the pretreatment of the rinse treatment. The film thickness of the liquid film is measured.

  The control device 7 determines the film thickness measurement result, information on the treatment liquid during the pretreatment, the use status during the pretreatment of each of the adjustment units 61, 62, 64, 76 and 77, the treatment conditions for the pretreatment, and each treatment. This is a function for predicting characteristics such as viscosity, surface tension, temperature, viscosity, and concentration of the liquid film on the semiconductor wafer W based on the liquid information.

  The function (2) of the control device 7 is a function in which the control device 7 determines the rinse condition from the characteristics of the liquid film on the semiconductor wafer W predicted by the function (1) and the information stored in the database 90. . That is, the optimum rinsing condition for the semiconductor wafer W is determined from the characteristics of the liquid film predicted by the function (1), the characteristics of the liquid film stored in the database 90, and the like. For example, the control device 7 determines the optimum processing liquid draining time, the processing liquid draining rotation speed, the rinsing time, the rinsing rotational speed, and the rinsing from the processing liquid stored in the database 90 and information on the rinsing processing conditions for the processing liquid. Select the type of treatment liquid.

  That is, the condition for the rinsing process is set based on the information in the database 90 so that the necessary rinsing process is performed with a processing solution or the like. Referring to FIG. 3, in the setting of the rinsing time, conditions for rinsing treatment are set (determined) such as increasing the rinsing time when the liquid film is the processing liquid A and shortening the rinsing time when the liquid film is the processing liquid B. )

  Note that the rinse condition is set so that the rinse process is completed by performing the rinse process a plurality of times. In other words, the rinsing process is controlled so that the processing liquid on the semiconductor wafer W is not replaced with the rinsing liquid in one rinsing process, but the processing liquid is replaced with the rinsing liquid at least twice. The device 7 determines the rinse condition.

  The function (3) of the control device 7 is a function for monitoring the characteristics of the liquid film during the rinsing process of the semiconductor wafer W performed under the rinsing condition determined in the function (2) and optimizing the rinsing time.

  In other words, the control device 7 performs the rinsing process of the semiconductor wafer W under the set rinsing condition, and always detects the film thickness of the liquid film on the semiconductor wafer (substrate) W by the monitor unit. From the detected characteristic of the liquid film on the semiconductor wafer W, the control device 7 resets the rinse time determined by the function (2) to an optimal rinse time and performs a rinse process.

  Specifically, during the rinsing process, the liquid film of the rinsing liquid is constantly monitored to predict the characteristics of the processing liquid in the same manner as the function (1). Is determined by the determination unit 7a, and the time for performing the rinsing process is reset. In other words, unnecessary rinsing treatment is prevented by resetting the preset rinsing time in accordance with the state of replacement of the liquid film by the rinsing treatment. As described above, the function (3) is a function of performing the rinsing process by feedback control based on the characteristics of the monitored liquid film. That is, the actual measurement result and the prediction are compared and resetting is performed.

  The function (4) of the control device 7 is a function for monitoring the drying characteristics of the rinsing liquid in the rinsing liquid drying process performed after the rinsing time reset in the function (3). Specifically, as shown in the relationship between the drying time of each solution and the film thickness of the film on the semiconductor wafer W in FIG. 4, when the rinse solution is dried, the rinse solution is A predetermined drying time is required to dry the predetermined film thickness. That is, the relationship between the film thickness of the rinse liquid film and the drying time has a predetermined inclination.

  The database 90 stores the characteristics (drying characteristics) at the time of drying the rinse liquid, which is the relationship (tilt) between the film thickness of the rinse liquid and the drying time shown in FIG. The drying characteristics of the liquid film and the drying characteristics of the rinse liquid stored in the database 90 are compared, and it is determined whether or not the processing liquid on the semiconductor wafer W has been replaced with the rinse liquid.

  When the drying characteristics of the rinsing liquid stored in the database 90 and the detected drying characteristics of the liquid film are the same, the control device 7 determines that the rinsing liquid has been replaced by the determination unit 7a, and performs the rinsing process. Exit. The control device 7 performs the rinsing process again when the rinsing liquid is not replaced, that is, when the drying characteristics of the rinsing liquid and the drying characteristics of the liquid film on the semiconductor wafer W are different.

Next, the rinsing process of the semiconductor wafer W by the substrate processing tank 1 of the substrate processing apparatus 100 configured as described above and the drying process after the rinsing process will be described with reference to the flowchart shown in FIG.
As shown in FIG. 5, first, the control device 7 emits light from the light source 81 and causes the camera 82 to recognize interference fringes of light reflected by the liquid film in the pretreatment of the rinsing process. The control device 7 measures the film thickness of the liquid film on the semiconductor wafer W by analyzing this information (step ST1). That is, the control device 7 measures the liquid film thickness of the treatment liquid used for the pretreatment of the rinse treatment.

  The control device 7 compares the processing liquid information such as the film thickness, the characteristics of the processing liquid used during preprocessing, and the data of the processing liquid with the characteristics of the processing liquid stored in the database 90. The control device 7 predicts the characteristics of the processing liquid, which is a liquid film on the semiconductor wafer W, as function (1) from the processing liquid information and the characteristics of the processing liquid stored in the database 90 (step ST2). Thereby, the control apparatus 7 determines the characteristic of a process liquid. In addition, the characteristics of the processing liquid to be predicted include the type, viscosity, surface tension, temperature, and concentration of the processing liquid.

  The control device 7 determines the rinse condition for the rinse process as function (2) from the predicted (determined) characteristic of the processing liquid (step ST3). The control device 7 performs a rinsing process from the determined rinsing condition (step ST4).

  In the explanatory view showing the relation between the liquid film thickness of the rinsing process and the processing time shown in FIG. 6, the rinsing process, that is, the replacement of the processing liquid and the removal of particles are performed on a line parallel to the drying time axis. Specifically, when the film thickness increases with time, the rinsing liquid is supplied onto the semiconductor wafer W so that the film thickness is gradually formed. When a certain amount of rinsing liquid is supplied, the rinsing liquid is supplied. A part of the rinsing liquid is scattered from the semiconductor wafer W, and the other part forms a liquid film having a constant film thickness. At this time, the treatment liquid and the particles are contained in the rinse liquid scattered from the semiconductor wafer W, so that the treatment liquid is gradually replaced with the rinse liquid.

  The control device 7 performs the rinsing process based on the rinsing condition, and confirms the replacement state by the rinsing process from the detected characteristics of the processing liquid (step ST5). When the replacement state predicted at the time of determining the rinse condition is different from the detected replacement state (YES in step ST5), the control device 7 again determines the rinse time of the rinse conditions as function (3). (Step ST6).

  If the replacement state predicted from the rinse condition is the same as the confirmed replacement state, that is, if the rinse process is performed according to the set rinse condition (NO in step ST5), has the rinse process time elapsed? It is determined whether or not (step ST7). If the rinse process time has not elapsed (NO in step ST7), the process returns to step ST4, and the rinse process is performed until the rinse process time elapses.

  If the rinsing process time has elapsed (YES in step ST7), the rinsing process is stopped (step ST8). Thereafter, the rinse liquid on the semiconductor wafer W is dried to perform a drying process (step ST9). As a function (4), the control device 7 monitors the drying characteristics as shown in FIGS. 4 and 6 from changes in the drying process time and the liquid film thickness during the drying process (step ST10).

  After the completion of the drying process, as shown in FIG. 4, the control device 7 determines whether or not the replacement is completed from the relationship between the film thickness during the drying process and the drying time, which is the monitored drying characteristics (step ST11). ). That is, the drying characteristics of the rinse liquid stored in the database 90 are compared with the monitored drying characteristics. If they are the same, it is determined that the treatment liquid has been replaced with the rinse liquid (YES in step ST11), and the rinsing process is performed. And a drying process is complete | finished. Thereby, the semiconductor wafer W is conveyed to the next process, and another process is performed in the next process.

  If the drying characteristics of the rinse liquid stored in the database 90 are different from the monitored drying characteristics, it is determined that the replacement with the rinse liquid is not completed (NO in step ST11), and the rinse condition is set again. Determination (step ST3) and rinsing processing are performed (step ST4). In this way, the control device 7 performs the rinsing process and the drying process a plurality of times until the replacement is completed. Note that the control device 7 determines the end of replacement when the monitored drying characteristics of the liquid film on the semiconductor wafer W are the same as the drying characteristics of the rinse liquid stored in the database 90.

  That is, as shown in FIG. 6, the rinsing liquid is supplied to perform the rinsing process, and the rinsing liquid supply is stopped to perform the drying process. The drying characteristics during the drying process are shown in FIG. The rinsing process and the drying process are repeated until the drying characteristics are similar to the stored drying characteristics of the rinse liquid and finally the drying characteristics are the same. In this way, the rinse process and the drying process are performed a plurality of times, and the monitored drying characteristics shown in FIG. 6 become the same as the drying characteristics stored in the database 90, thereby completing the replacement.

  In the explanation of the rinsing process and the drying process shown in FIG. 6, the processing liquid used in FIG. 6 has, for example, a quick drying time or a viscosity like the processing liquid B in FIGS. It is a processing solution with low characteristics. As shown in FIG. 6, the rinsing process and the drying process are performed a plurality of times, so that the drying time of the rinsing liquid (processing liquid) gradually increases, and finally the same inclination as the rinsing liquid shown in FIG. 5. Become. Thereby, it is determined that the treatment liquid has been replaced with the rinse liquid by the rinse treatment, and the rinse treatment is completed.

  According to the substrate processing apparatus 100 using the substrate processing tank 1 configured as described above, the rinse treatment and the drying treatment are repeatedly performed a plurality of times, thereby reducing the amount of contaminants attached to the semiconductor wafer W by replacing the rinse liquid. It becomes possible. Further, as shown in FIG. 7, by performing the rinse treatment and the drying treatment a plurality of times, it becomes possible to reduce the amount of substitution and the amount of contaminants as compared with the conventional rinse treatment and the drying treatment only once. At the same time, the rinsing time can be shortened and the amount of the rinsing liquid can be reduced.

  This is because, from a general flow velocity distribution, the flow velocity is large on the surface side of the liquid film, and the flow velocity of the liquid film is regarded as substantially zero on the surface of the semiconductor wafer W. The surface is the main. Therefore, in the liquid rinsing process, the liquid film on the semiconductor wafer W rotated by the turntable 16 stops the processing liquid located on the surface of the semiconductor wafer W, and is not easily replaced. Further, even if physical processing is performed by the rinsing liquid sprayed in the form of mist, the processing liquid and the rinsing liquid convect in the liquid film, so that there is a possibility that contaminants and processing liquid located on the surface side of the semiconductor wafer W may remain. is there.

  Due to such factors, the time required to replace the rinse liquid becomes longer. On the other hand, since the rinsing liquid containing the processing liquid on the semiconductor wafer W is scattered by rotation by stopping the supply of the rinsing liquid and performing the drying process, the processing liquid and the contaminants on the semiconductor wafer W are scattered. The amount is reduced. Thereby, the ratio of a process liquid and a contaminant in the next rinse process reduces with respect to a rinse liquid. For this reason, it becomes possible to perform a rinse process efficiently and it becomes easy to replace a process liquid with a rinse liquid. For this reason, the replacement time and the amount of rinse solution used are reduced.

  Further, by stopping the supply of the rinsing liquid, the liquid film thickness is gradually reduced, and the influence of the low flow velocity on the surface of the semiconductor wafer W due to the flow velocity distribution during rotation can be reduced. That is, in the liquid film immediately before the end of the drying process, the distance between the surface of the liquid film and the surface of the semiconductor wafer W can be shortened, so that the flow velocity on the surface side of the semiconductor wafer W increases and the flow velocity on the surface side of the semiconductor wafer W decreases. Thus, the processing liquid and contaminants near the surface of the semiconductor wafer W can be efficiently scattered. For this reason, it becomes possible to reduce the quantity of the rinse liquid required for substitution of the rinse liquid by a rinse process, and the time of a rinse process.

  Further, the liquid film thickness is constantly detected by the light source 81, the camera 82, and the control device 7, and the characteristics of the liquid film are predicted by comparing with the characteristics of the processing liquid stored in the database 90, thereby rinsing with high accuracy. It becomes possible to determine the conditions.

  By determining the characteristics of the processing liquid on the semiconductor wafer W before the rinsing process, it is possible not only to improve the accuracy of the rinsing conditions but also to find a failure in the substrate processing tank 1. That is, in the substrate processing, if the processing liquid being used and the characteristics of the detected liquid film are significantly different, it is determined that the first and third concentration adjustment units 62 and 77 have failed before rinsing. It is also possible to do.

  In addition, it is possible to optimize the rinsing time by checking the replacement state during the rinsing process, and it is possible to perform the rinsing process again by checking the replacement state during the drying process. That is, the liquid film is monitored to predict the characteristics of the liquid film, and the rinsing process is performed by feeding back the predicted characteristics, so that the rinsing process is wasteful compared to the case where the conventional rinsing time is determined in advance. Processing can be prevented. That is, the rinse time can be shortened, and the rinse process can be performed again as necessary, so that the rinse process can be performed with high accuracy.

  Thus, it is possible to reduce the rinsing process, and the rinsing process time is reduced. By reducing the rinsing time, the amount of rinsing liquid used is reduced and the productivity is improved.

  As described above, according to the substrate processing apparatus 100 according to the present embodiment, the confirmation of the replacement state in the rinsing process and the drying process, and the rinsing process and the drying process are performed a plurality of times, thereby reducing the rinsing process time. And it becomes possible to reduce the usage-amount of a rinse liquid. Thereby, the productivity of the semiconductor wafer W can be improved.

  The present invention is not limited to the above embodiment. In the example described above, after the drying process is completed, the control device 7 compares the monitored drying characteristics with the drying characteristics of the rinsing liquid in the database 90 to determine whether or not the replacement is completed. Not limited to. For example, as shown in FIG. 8, when the drying characteristics monitored during the drying process shown in FIG. 8 are compared with the drying characteristics of the rinsing liquid in the database 90 shown in FIG. The rinsing process may be performed by stopping the drying process at that time and supplying the rinse liquid.

  Moreover, in the example mentioned above, although the substitution state was confirmed during the rinse treatment and in the dry state, either the rinse treatment or the dry state may be used. By confirming the replacement state on either one, the accuracy of the rinsing process is improved as compared with the case where confirmation is not performed.

  Further, in the above-described example, the substrate processing apparatus 100 includes the rotary table 16 and the substrate processing tank 1 that rotates the semiconductor wafer W. However, instead of the substrate processing tank 1 including the rotary table 16, for example, Alternatively, a processing apparatus that transports the semiconductor wafer W by rollers or the like and processes the semiconductor wafer W at a certain position may be used.

  Further, in the above-described example, the monitor unit is configured to irradiate the semiconductor wafer W with light from the light source 81 and recognize the light reflected by the liquid film with the camera 82 as the film thickness detection means, but is not limited thereto. . For example, it may be a monitor unit that detects the thickness of the liquid film not by light but by laser light or electrostatic capacity, and may have another configuration as long as the thickness of the liquid film can be detected.

  Furthermore, in the above-described example, the upper nozzle body 51 and the oblique nozzle body 71 are provided as the plurality of nozzle bodies, but a configuration having other nozzle bodies may be employed. Moreover, the structure which has a nozzle body which can inject only the pure water used for a rinse process may be sufficient. In the case of this nozzle body, it is not necessary to provide an adjustment unit for adjusting the density, and only a temperature adjustment unit may be provided. Further, instead of the plurality of nozzle bodies, a configuration having only one, for example, the upper nozzle body 51 may be used.

  In the above-described example, a plurality of times of rinsing and drying are performed. However, the rinsing and drying may be performed only once. If the rinse process and the drying process are performed only once compared to the multiple rinse processes and the drying process, the effect of reducing the processing time cannot be expected. However, by detecting the film thickness of the liquid film and predicting the characteristics of the processing liquid (function (1)) and optimizing the processing time (function (3)), the processing effect and accuracy are improved. It becomes possible.

  Moreover, although the rinse process was demonstrated in the example mentioned above, it can be applied not only to the rinse process but also to other processes. In addition, various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Substrate processing tank, 2 ... Cup body, 3 ... Lower cup, 3a ... Through hole, 4 ... Upper cup, 5 ... Discharge pipe, 6 ... Exhaust pump, 7 ... Control device (Drying means, control means, film thickness detection) Means), 7a ... Determining part, 8 ... Base plate, 9 ... Mounting hole, 11 ... Control motor, 12 ... Stator, 13 ... Rotor, 14 ... Connector, 15 ... Bridge part, 16 ... Rotating table (drying means) ), 17 ... Holding member, 18 ... Support pin, 21 ... Turbulence prevention cover, 22 ... Outer peripheral wall, 22a ... Small diameter part, 22b ... Large diameter part, 23 ... Top wall, 25 ... Ring-shaped member, 31 ... Opening , 32... Fan / filter unit, 33... Drive unit, 34 .. inlet / outlet port, 35... Shutter, 36 .. cylinder, 37 .. control valve, 51 ... upper nozzle body (first and second processing liquid supply means), 52 ... arm body, 53 ... mounting member, 55 ... rotating shaft, 56 ... rotational drive source, DESCRIPTION OF SYMBOLS 7 ... Output shaft, 58 ... 1st supply pipe, 59 ... 2nd supply pipe, 60 ... 1st solenoid valve, 61 ... 1st temperature adjustment unit, 62 ... 1st density | concentration adjustment unit, 63 ... 2nd solenoid valve 64 ... second temperature adjustment unit, 71 ... oblique nozzle body (first and second processing liquid supply means), 72 ... third mounting member, 74 ... third supply pipe, 75 ... third solenoid valve, 76 ... third temperature adjustment unit, 77 ... third concentration adjustment unit, 81 ... light source (film thickness detection means), 82 ... camera (film thickness detection means), 90 ... database (storage means), 100 ... substrate processing apparatus, DESCRIPTION OF SYMBOLS 101 ... Cassette station, 102 ... Cassette, 103 ... Loader part, 104 ... Unloader part, 105 ... Unit, 106 ... Robot, 107 ... Arm, W ... Substrate (semiconductor wafer), S ... Signal line.

Claims (8)

A substrate processing apparatus for processing a substrate with a first processing liquid and then processing with a second processing liquid,
First processing liquid supply means for supplying the first processing liquid onto the substrate;
Second processing liquid supply means for supplying the second processing liquid onto the substrate supplied with the first processing liquid;
A film thickness detecting means for detecting the thickness of the liquid film on the substrate supplied with the second processing liquid;
Control means having a determination unit for determining whether or not the first treatment liquid supplied to the substrate is replaced with the second treatment liquid based on detection by the film thickness detection means;
A substrate processing apparatus comprising: Drying means for drying the liquid film on the substrate supplied with the second treatment liquid;
And further storing means for storing drying characteristics during drying of the second treatment liquid,
The control means, when the liquid film is dried by the drying means, based on the detection of the film thickness detection means, the drying characteristics of the film thickness of the liquid film, and the second stored in the storage means. The substrate processing apparatus according to claim 1, wherein it is determined whether or not the first processing liquid is replaced with the second processing liquid by comparing characteristics when the processing liquid is dried. . Storage means for storing the characteristics of the second treatment liquid,
When the second processing liquid is supplied onto the substrate by the second processing liquid supply means, the control means is configured to detect the liquid film on the substrate based on detection by the film thickness detection means. In addition to predicting the characteristics, comparing the predicted characteristics of the second processing liquid with the characteristics of the second processing liquid stored in the storage means, the first processing liquid is The substrate processing apparatus according to claim 1, wherein it is determined whether or not the second processing liquid has been replaced.   The control means causes the second processing liquid supply means to further supply the second processing liquid onto the substrate when the first processing liquid is not replaced with the second processing liquid. The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus is a substrate processing apparatus. A substrate processing method of processing a substrate with a first processing liquid and then processing with a second processing liquid,
Supplying the first treatment liquid onto the substrate;
Supplying the second processing liquid onto the substrate supplied with the first processing liquid;
Detecting the film thickness of the liquid film on the substrate supplied with the second treatment liquid;
Determining whether the first treatment liquid supplied to the substrate is replaced with the second treatment liquid based on the detection of the film thickness;
The substrate processing method characterized by comprising. Drying the liquid film on the substrate supplied with the second treatment liquid; and
By comparing the drying characteristics of the liquid film detected when the liquid film is dried with the drying characteristics of the second processing liquid during drying, the first processing liquid is converted into the second processing liquid. 6. The substrate processing method according to claim 5, wherein it is determined whether or not the processing liquid has been replaced. Predicting the characteristics of the liquid film from the detected liquid film thickness on the substrate when the second processing liquid is supplied onto the substrate by the second processing liquid supply means; Further comprising
By comparing the predicted characteristics of the liquid film with the characteristics of the second treatment liquid, it is determined whether or not the first treatment liquid has been replaced with the second treatment liquid. The substrate processing method according to claim 5.   6. The method according to claim 5, further comprising the step of further supplying the second processing liquid onto the substrate when the first processing liquid is not replaced with the second processing liquid. Item 8. The substrate processing method according to Item 7.

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