JP2010278374A - Adsorption detection resolving method, processing apparatus, and computer-readable storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adsorption detection resolving method that reduces the possibility that a substrate is damaged and detects whether the substrate is adsorbed on a placing table and resolves the adsorption. <P>SOLUTION: There are provided a process for supplying a fluid, from a placing surface of a placing table to the rear surface of a workpiece with a predetermined adsorption determining pressure (step 2); a process to detect a flow amount of the fluid, when the predetermined adsorption determining time has elapsed from the start of supplying the fluid with the adsorption determining pressure; a process to determine whether the fluid flow amount detected in the process is equal to or less than a predetermined adsorption determining flow amount (step 3); and a process for controlling the pressure to supply the fluid against the rear surface of the workpiece to be an adsorption resolution pressure higher than the adsorption determining pressure, when the fluid flow amount is equal to or less than the adsorption determining flow amount and the result of determining the process (step 7). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a suction detection cancellation method for detecting whether or not a substrate such as a glass substrate is sucked on a mounting table, a processing apparatus capable of executing this suction detection cancellation method, and the suction detection cancellation. The present invention relates to a computer-readable storage medium storing a program for causing a processing device to execute a method.

  When manufacturing a liquid crystal display, a plasma processing apparatus such as a dry etching apparatus is used to form an electrical element on a glass substrate. The plasma processing apparatus includes a mounting table on which a substrate is mounted, and the surface of the mounting table is covered with an insulator such as an anodic oxide film in order to prevent abnormal discharge due to plasma.

  When a glass substrate, which is an insulator, is subjected to plasma treatment on a mounting table covered with an insulating material, the surface of the substrate or the mounting table may be charged and both may be adsorbed. When the lifter pin is driven to carry out the substrate when both are adsorbed, the substrate cannot be lifted and cracks if the adsorbing force is strong.

  Therefore, in Patent Document 1, when the substrate is pushed up by the lifter pin, data on the electrostatic adsorption force to the substrate mounting table is detected, and when the electrostatic adsorption force is a predetermined value or more, the lifter pin pushes up. A method of handling a substrate whose operation is restricted is described.

  Further, in Patent Document 2, when the electrostatic attraction force is strong, the heat transfer gas is supplied between the substrate and the mounting table, and the substrate is pushed up by the lifting force by the lifter pin and the pressure by the heat transfer gas. A substrate removal control method is described.

  Further, in Patent Document 3, when the sample is separated from the sample holding part after film formation or etching treatment, a gas such as argon or helium is equally applied as a push-up force to many portions on the lower surface of the sample. The charge accumulated in the sample is released by irradiating with plasma. A sample detachment method is described in which the sample is detached from the sample holder when the residual adsorptive power becomes smaller than the gas pressure.

Japanese Patent Laid-Open No. 11-260897 Japanese Patent Laid-Open No. 2000-200245 JP-A-7-130825

  Glass substrates are becoming thinner and larger. For this reason, as in Patent Documents 1 and 2, in the method of determining the strength of the electrostatic adsorption force based on the pressure applied to the lifter pin, is the electrostatic adsorption force acting between the substrate and the mounting table? Regardless of whether or not the lifter pin is driven, there is an increased possibility that the glass substrate is damaged.

  Patent Document 3 only describes a sample detachment method, and does not determine whether the sample and the sample holder are adsorbed.

  Further, the detachment method described in Patent Document 3 increases the gas pressure until the sample is detached from the sample holder. For this reason, when the sample is easily damaged like a glass substrate, if the sample is strongly adsorbed to the sample holder, the sample may be damaged before it is detached from the sample holder. There is.

  The present invention has been made in view of the above circumstances, and a suction detection canceling method for detecting and canceling whether or not a substrate is sucked on a mounting table while reducing the possibility of the substrate being damaged, and this suction detection It is an object of the present invention to provide a processing apparatus capable of executing a resolution method and a computer-readable storage medium storing a program for causing the processing apparatus to execute the adsorption detection resolution method.

  In order to solve the above-mentioned problem, the suction detection elimination method according to the first aspect of the present invention provides a method in which the object to be processed is placed on the mounting table before the object to be processed is detached from the mounting table on which the object to be processed is mounted. It is an adsorption detection elimination method for detecting whether or not the sample is adsorbed on the surface and canceling the adsorption if adsorbed. (1) From the mounting surface of the mounting table to the back surface of the object to be processed A step of supplying a fluid at a predetermined adsorption determination pressure; and (2) a step of detecting a flow rate of the fluid when a predetermined adsorption determination time has elapsed after the fluid supply is started at the adsorption determination pressure. And (3) a step of determining whether or not the flow rate of the fluid detected in the step (2) is equal to or lower than a predetermined adsorption determination flow rate, and (4) a result of the determination in the step (3), If the fluid flow rate is less than or equal to the adsorption determination flow rate, Comprising a step of adsorption overcome the pressure of the high pressure, the than the suction determining pressure pressure supplying fluid to.

  Further, the processing apparatus according to the second aspect of the present invention is configured to be able to project and retract from the mounting table on which the object to be processed is mounted and the mounting surface of the mounting table, and above the mounting surface of the mounting table A lifter pin for moving the substrate up and down, a plurality of gas holes provided on the mounting surface of the mounting table, a gas supply pipe connected to the plurality of gas holes, and supplying gas to the gas supply pipe A gas supply mechanism, a pressure adjustment mechanism that is provided in the gas supply pipe and adjusts the flow rate of the gas supplied to the gas supply pipe so that the pressure in the gas supply pipe becomes a set pressure; And a control mechanism for controlling at least one of the pressure adjustment mechanism and the lifter pin so as to execute the adsorption detection elimination method according to the above aspect.

  A computer-readable storage medium according to a third aspect of the present invention is a computer-readable storage medium that stores a control program that operates on a computer and controls a processing device. At the time of execution, the processing apparatus is controlled so that the suction detection elimination method according to the first aspect is performed.

  According to the present invention, it is possible to execute the suction detection canceling method and the suction detection canceling method for detecting and canceling whether or not the substrate is sucked on the mounting table while reducing the possibility of the substrate being damaged. And a computer-readable storage medium storing a program for causing the processing apparatus to execute the adsorption detection elimination method.

Sectional drawing which shows roughly an example of the substrate processing apparatus which can implement the adsorption | suction detection cancellation method which concerns on 1st Embodiment of this invention The figure which shows the state which mounted the board | substrate on the mounting base Diagram showing the state without adsorption Diagram showing the state with adsorption Diagram showing changes in gas flow rate with and without adsorption The flowchart which shows an example of the adsorption | suction detection cancellation sequence which concerns on 1st Embodiment of this invention The flowchart which shows an example of the adsorption | suction detection cancellation sequence which concerns on 2nd Embodiment of this invention The figure which shows the change of the gas flow rate with the presence or absence of adsorption and the presence or absence of adsorption The figure which shows an example of the state which is bending the board | substrate G

  Embodiments of the present invention will be described below with reference to the drawings. Note that common parts are denoted by common reference numerals throughout the drawings.

(First embodiment)
FIG. 1 is a cross-sectional view schematically showing an example of a processing apparatus capable of carrying out the adsorption detection eliminating method according to the first embodiment of the present invention. In this example, as a processing apparatus, a plasma etching apparatus that performs plasma etching on a substrate that is an object to be processed, for example, a glass substrate (hereinafter simply referred to as “substrate”) G for a flat panel display (FPD) is illustrated. . The present invention is not limited to the plasma etching apparatus.

  As shown in FIG. 1, the plasma etching apparatus 1 is configured as a capacitively coupled parallel plate plasma etching apparatus that performs etching on a substrate G.

  The plasma etching apparatus 1 includes a chamber 2 as a processing container that accommodates the substrate G. The chamber 2 is made of, for example, aluminum whose surface is anodized (anodized), and is formed in a square tube shape corresponding to the shape of the substrate G.

  On the bottom wall of the chamber 2 is provided a mounting table (stage) 3 on which the substrate G is mounted via an insulator 3b. The mounting table 3 is formed in a square plate shape corresponding to the shape of the substrate G, and is connected to a high-frequency power source 7 in this example. In addition, a plurality of gas holes 4 through which an inert gas flows out toward the back surface of the substrate G are formed in the mounting surface 3 a on which the substrate G of the mounting table 3 is mounted. Each of the plurality of gas holes 4 is connected to an inert gas supply pipe 5 to which an inert gas is supplied. Although not particularly shown, the surface of the mounting table 3 is covered with an insulator such as an anodic oxide film in order to prevent abnormal discharge due to plasma.

  A shower head 6 for supplying a processing gas into the chamber 2 is provided on the upper wall of the chamber 2 so as to face the mounting table 3. The shower head 6 includes a gas diffusion space 6 a for diffusing the processing gas therein, and a plurality of discharge holes 6 b for discharging the processing gas on the surface facing the mounting table 3. In this example, the shower head 6 is grounded and constitutes a pair of parallel plate electrodes together with the mounting table 3.

A gas inlet 6 c is provided on the upper surface of the shower head 6. The gas inlet 6 c is connected to the processing gas supply pipe 8. A processing gas for etching is supplied to the processing gas supply pipe 8 from a processing gas supply source (not shown) via a valve and a mass flow controller (not shown). As the processing gas, a gas usually used in this field, such as a halogen-based gas, an O ₂ gas, or an Ar gas, can be used.

  An exhaust pipe 9 is connected to the bottom wall of the chamber 2. The exhaust pipe 9 is connected to an exhaust device (not shown). The inside of the chamber 2 can be evacuated to a predetermined reduced pressure atmosphere by exhausting it using an exhaust device (not shown).

  A loading / unloading port 10 for loading and unloading the substrate G is formed on the side wall of the chamber 2. The loading / unloading port 10 is opened and closed by a gate valve 11.

  The bottom wall of the chamber 2 and the mounting table 3 are formed with a plurality of insertion holes 12 penetrating therethrough. A lifter pin 13 that supports the substrate G from below and moves up and down is inserted into the plurality of insertion holes 12 so as to protrude and retract with respect to the placement surface 3a. FIG. 1 shows a state in which the lifter pins 13 protrude from the mounting surface 3 a and hold the substrate G above the mounting table 3. In FIG. 1, for the sake of convenience, the plurality of insertion holes 12 are illustrated only in the peripheral portion of the mounting table 3, but the plurality of insertion holes 12 are also formed in the central portion of the mounting table 3.

  The control unit 14 controls the plasma etching apparatus 1. The control unit 14 includes a controller 141, a user interface 142, and a storage unit 143. The user interface 142 includes a keyboard on which the process manager inputs commands to manage the plasma etching apparatus 1, a display that visualizes and displays the operating status of the plasma etching apparatus 1, and the like. The storage unit 143 stores a recipe in which a control program for realizing the processing by the plasma etching apparatus 1 under the control of the controller 141, driving condition data, and the like are recorded. The recipe is called from the storage unit 143 by an instruction from the user interface 142 as necessary, and the plasma etching apparatus 1 is controlled by causing the controller 141 to execute the recipe. For example, a recipe stored in a computer-readable storage medium such as a CD-ROM, a hard disk, or a flash memory may be used, or may be transmitted from another device at any time via a dedicated line, for example. It is also possible to use it.

  As described above, the mounting table 3 included in the plasma etching apparatus 1 is connected to the inert gas supply pipe 5 and the inert gas supply pipe 5 so that the inert gas flows from the mounting surface 3a toward the back surface of the substrate G. It has a plurality of gas holes 4 to be discharged. A pressure adjustment valve (PCV) 15 is provided upstream of the inert gas supply pipe 5, and is connected to the inert gas supply mechanism 16 via the pressure adjustment valve 15. As the inert gas, nitrogen gas can be used in addition to a rare gas such as helium (He) gas and argon (Ar) gas. The pressure adjustment valve 15 controls the flow rate of the inert gas supplied to the inert gas supply pipe 5 so that the pressure P1 in the inert gas supply pipe 5 becomes the pressure P0 preset by the controller 141.

  The gas hole 4, the inert gas supply pipe 5, the pressure adjustment valve 15, and the inert gas supply mechanism 16 may use a substrate cooling mechanism or the like that is already installed on the mounting table 3.

  First, a method for confirming the adsorption state according to the first embodiment of the present invention will be described.

  FIG. 2 is a diagram showing a state where a substrate is placed on a mounting table, FIG. 3 is a diagram showing a state without adsorption, and FIG. 4 is a diagram showing a state with adsorption.

  After the plasma processing is completed, the method for confirming the suction state in the state where the substrate G is placed on the placement surface 3a of the placement table 3 (see FIG. 2) is as follows.

  (1) The set pressure of the pressure adjusting valve 15 is set to P0, and the inert gas is supplied to the inert gas supply pipe 5. The set pressure P0 is set lower than the pressure of the back cooling gas used for substrate cooling.

  (2) After a predetermined adsorption determination time t1 has elapsed since the start of supplying the inert gas to the inert gas supply pipe 5, the gas flow rate Q flowing through the inert gas supply pipe 5 by the pressure adjustment valve 15 is detected. . Based on the magnitude of the gas flow rate Q at this time, the presence or absence of adsorption between the substrate G and the mounting table 3 is determined.

  When the substrate G is not adsorbed on the mounting table 3 or is weakly adsorbed (in the case of “no adsorption” or “adsorption weak”), when the inert gas is supplied to the inert gas supply pipe 5, the substrate G rises. A large gap 100 is generated between the mounting surface 3a and the back surface of the substrate G (see FIG. 3). Since the inert gas flowing out from the gas hole 4 flows through the large gap 100, the pressure P1 in the inert gas supply pipe 5 is difficult to increase. For this reason, even if the adsorption determination time t1 has elapsed from the start of the supply of the inert gas, the pressure P1 in the inert gas supply pipe 5 cannot reach the set pressure P0 (P0 >> P1). Since the pressure P1 in the inert gas supply pipe 5 does not reach the set pressure P0, the gas flow rate Q that the pressure adjustment valve 15 flows to the inert gas supply pipe 5 is the maximum gas flow rate Q1 that the pressure adjustment valve 15 can flow. It becomes.

  When the substrate G is adsorbed on the mounting table 3, that is, when the adsorption is strong (“with adsorption” or “adsorption strong”), the substrate G is unlikely to float. Since the substrate G hardly floats, there is no gap between the mounting table 3 and the substrate G, or only a small gap 101 is generated as compared with the case of “no suction” (see FIG. 4). The leakage of the inert gas flowing out from the gas hole 4 is greatly limited as compared with the case of “no adsorption”, and the pressure P1 in the inert gas supply pipe 5 is likely to increase. For this reason, when the adsorption determination time t1 has elapsed, the gas flow rate Q that the pressure adjusting valve 15 flows through the inert gas supply pipe 5 is a flow rate Q2 that is smaller than the gas flow rate Q1 in the case of “no adsorption”.

  Thus, depending on the presence or absence of adsorption, the gas flow rate Q that the pressure adjustment valve 15 flows through the inert gas supply pipe 5 when the adsorption determination time t1 has elapsed since the start of the supply of the inert gas to the active gas supply pipe 5 is apparent. There will be a difference. By utilizing this difference, the presence or absence of adsorption can be determined as follows.

  FIG. 5 is a diagram showing a change in gas flow rate depending on the presence or absence of adsorption.

As shown in FIG. 5, the adsorption determination time t <b> 1 is set to a time during which the gas flow rate Q <b> 1 flowing through the pressure adjustment valve 15 is almost stable when “no adsorption”.
Further, an adsorption determination flow rate A is set between a large gas flow rate Q1 that the pressure adjustment valve 15 flows when “no adsorption” and a small gas flow rate Q2 when “adsorption”. Then, whether the gas flow rate Q at the adsorption determination time t1 is equal to or higher than the adsorption determination flow rate A (or whether it exceeds the adsorption determination flow rate A) is determined as “with adsorption” or “without adsorption”.

  Next, a specific adsorption detection sequence will be described together with an adsorption elimination sequence.

  FIG. 6 is a flowchart showing an example of the adsorption detection cancellation sequence.

  First, the substrate G is mounted on the mounting table 3, and processing, for example, plasma processing is performed on the substrate G mounted on the mounting table 3, and this is finished (step 1).

  Next, with the substrate G having been subjected to the plasma treatment being placed on the placement table 3, the set pressure of the pressure adjustment valve 15 is set to the adsorption determination pressure P 0, and the inert gas is supplied to the inert gas supply pipe 5. Then, the gas is discharged from the gas hole 4 (step 2).

  After the adsorption determination time t1, elapses, it is determined whether or not the gas flow rate Q flowing through the pressure adjustment valve 15 is equal to or higher than the adsorption determination flow rate A (step 3).

  When the gas flow rate Q is equal to or higher than the adsorption determination flow rate A (YES), it is determined that “no adsorption (= adsorption weak)” (step 4), the supply of the inert gas is stopped, and the lifter pin 13 is driven (increase) The substrate G is detached from the mounting table 3 (step 5).

  Conversely, when the gas flow rate Q is less than the adsorption determination flow rate A (NO), it is determined that “with adsorption (= adsorption strength)” (step 6). If it is adsorbed in this way, the process proceeds to the adsorption elimination sequence.

  In the adsorption elimination sequence, the set pressure of the pressure adjustment valve 15 is set to an adsorption elimination pressure P3 that is higher than the adsorption determination pressure P0 (step 7).

  Whether the gas flow rate Q flowing through the pressure adjustment valve 15 is equal to or higher than the adsorption determination flow rate B after the set pressure of the pressure adjustment valve 15 is set to the adsorption cancellation determination pressure P3 until the adsorption cancellation determination time t2 elapses. It is determined whether or not (step 8). Here, the value of the adsorption elimination determination flow rate B is set smaller than the value of the adsorption determination flow rate A.

  If the gas flow rate Q does not reach the adsorption elimination determination flow rate B within the adsorption elimination judgment time t2 (NO), it is judged as “adsorption no elimination” and the process proceeds to a state confirmation sequence described later.

  On the contrary, when the gas flow rate Q reaches the cancellation determination flow rate B within the adsorption cancellation determination time t2 (YES), it is temporarily determined that “adsorption has been canceled”, and the process proceeds to Step 10.

  In step 10, it is determined again whether the gas flow rate Q supplied to the back surface of the substrate G is greater than or equal to the adsorption determination flow rate A or exceeds the adsorption determination flow rate A, and the substrate G is adsorbed to the mounting table 3. Re-determine whether or not

  When the gas flow rate Q is equal to or higher than the adsorption determination flow rate A (YES), it is determined that “adsorption is canceled (= adsorption weak)” (step 11), the supply of the inert gas is stopped, and the lifter pin 13 is driven (increase) The substrate G is detached from the mounting table 3 (step 5).

  On the other hand, when the gas flow rate Q is less than the adsorption determination flow rate A (NO), it is determined that “adsorption has not been resolved” and the process proceeds to a state confirmation sequence.

  In the state confirmation sequence, the supply of the inert gas to the inert gas supply pipe 5 is stopped, a warning is generated (step 14), and the process is stopped (step 15).

  Here, in steps 7 to 10, the pressure P0 is gradually increased to P3, and each time or in parallel with the increase in pressure, whether or not the adsorption determination flow rate B is equal to or higher than the adsorption determination flow rate A. It may be determined whether or not. In step 10, when it is determined again whether or not the substrate G is attracted to the mounting table 3, the determination may be performed after the pressure P3 is lowered to P0.

  As described above, in the first embodiment, the operation moves to the operation of driving (raising) the lifter pin 13 and removing the substrate G from the mounting table 3 only when there is no suction or when the suction is canceled. The possibility of breakage of the substrate can be reduced.

(Second Embodiment)
Next, an adsorption detection elimination method including another adsorption elimination method will be described as a second embodiment of the present invention.

  FIG. 7 is a flowchart showing an adsorption detection elimination sequence according to the second embodiment of the present invention. Steps 1 to 10 of the suction detection cancellation sequence according to the second embodiment shown in FIG. 7 are the same as Steps 1 to 10 in the suction detection cancellation sequence described in the first embodiment.

  However, in the suction detection cancellation sequence according to the second embodiment, if it is determined in step 8 or step 10 that “suction has not been canceled”, the lifter pin 13 below the peripheral edge of the substrate G is driven to drive the substrate G. The peripheral edge of the substrate G is lifted, and the peripheral edge of the substrate G is peeled off from the mounting table 3 within the allowable range of bending of the substrate G (step 9). An example of a state where the substrate G is bent is shown in FIG.

  As shown in FIG. 9, the substrate G is bent within the allowable bending range, and the peripheral edge of the substrate G is peeled off from the mounting surface 3 a of the mounting table 3. Thereby, the clearance gap between the back surface of the board | substrate G and the mounting surface 3a of the mounting base 3 spreads. As a result, the outflow amount of the inert gas from the gas hole 4 is increased, so that more inert gas comes into contact with the back surface of the substrate G and the mounting surface 3a, the charge removal of the substrate G proceeds, and the adsorption is eliminated. Is promoted. Since the range in which the peripheral edge of the substrate G is lifted is within the allowable bending range of the substrate G, there is no possibility that the substrate G is damaged.

  As the peripheral portion of the substrate G to be lifted, only the four corners of the substrate G may be used, only two opposite sides of the substrate G may be used, or all the peripheral portions of the substrate G may be lifted.

  In any case, it is sufficient that the substrate G is not simply lifted but can be lifted so that only the peripheral edge of the substrate G is peeled off from the mounting table 3.

  Furthermore, after driving the lifter pin 13 below the peripheral edge of the substrate G, whether or not the flow rate of the gas supplied to the back surface of the substrate G is equal to or higher than the adsorption determination flow rate A or exceeds the adsorption determination flow rate A. It is determined again whether or not the adsorption of the substrate G to the mounting table 3 has been resolved (step 12). This determination is continued until the time limit. A specific example is the same as step 3, and it is determined whether or not the gas flow rate Q flowing through the pressure adjustment valve 15 is, for example, equal to or higher than the adsorption determination flow rate A at the adsorption determination time t1.

  When the gas flow rate Q is equal to or higher than the adsorption determination flow rate A (YES), it is determined that “adsorption is canceled (= adsorption weak)” (step 13), the supply of the inert gas is stopped, and the lifter pin 13 is driven (increase) The substrate G is detached from the mounting table 3 (step 5).

  Specifically, as shown in FIG. 8, when the lifter pin 13 below the peripheral portion of the substrate G is driven, the gas flow rate Q increases and the adsorption determination pressure A is exceeded.

  On the other hand, when the gas flow rate Q is less than the adsorption determination flow rate A even if the time limit is exceeded (NO), as shown in FIG. 8, it is determined as “timeout” and, for example, a warning is generated (step) 14) The processing is stopped (step 15).

  As described above, according to the suction detection elimination method according to the second embodiment, when the suction is not eliminated even if the pressure applied to the back surface of the substrate G is increased, only the peripheral edge of the substrate G is peeled from the mounting table. To promote adsorption elimination. For this reason, compared with the case where adsorption is canceled only by the pressure of gas, the probability that adsorption can be canceled can be raised more.

  In addition, the lifter pin 13 below the peripheral edge of the substrate G is simply raised and the peripheral edge of the substrate G is not peeled off from the mounting table 3, but the lifter pin 13 is moved up and down within a time limit, so that the substrate G You may make it lift the outside repeatedly.

  As mentioned above, although this invention was demonstrated according to two embodiment, as shown to the flowchart of FIG.6 and FIG.7, the adsorption | suction detection cancellation method which concerns on these embodiments determines the presence or absence of adsorption | suction, and even when there exists adsorption | suction The adsorption can be eliminated and the production can be performed without stopping the operation of the apparatus. For this reason, it is possible to maintain the throughput of the product and further improve the throughput.

  Thus, according to the present invention, the suction detection canceling method for detecting and canceling whether or not the substrate G is sucked onto the mounting table 3 while reducing the possibility of the substrate G being damaged, and the suction detection canceling. A substrate processing apparatus capable of executing the method and a computer-readable storage medium storing a program for causing the substrate processing apparatus to execute the adsorption detection elimination method can be provided.

  The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above embodiment, the pressure adjustment valve 15 controls the flow rate of the inert gas supplied to the inert gas supply pipe 5 so that the pressure P1 in the inert gas supply pipe 5 becomes the set pressure P0. However, if the pressure is between the pressure adjusting valve 15 and just below the substrate G, such as the pressure between the substrate G and the mounting table 3 or the pressure in the gas hole 4, the pressure at an arbitrary position is not set to the set pressure P 0. The flow rate of the inert gas supplied to the active gas supply pipe 5 may be controlled.

  Further, when fluid is supplied from the mounting surface 3a of the mounting table 3 to the back surface of the substrate G, only the central portion of the substrate G may swell and the substrate G may be damaged. When it is desired to eliminate such a situation, the displacement of the bulge in the central portion of the substrate G is monitored using an optical sensor or the like, and when the bulge reaches, for example, the limit of deflection, the fluid supply is temporarily performed. Is stopped, and the flexure is eliminated. Then, the lifter pin 13 below the peripheral portion of the substrate G is driven together with the fluid supply to lift the peripheral portion of the substrate G, and the peripheral portion of the substrate G is bent. You may make it bend within the tolerance | permissible_range and make it peel from the mounting base 3. FIG. In this way, by peeling the peripheral edge of the substrate G from the mounting table 3, gas escapes from the bulge, and damage to the substrate G can be suppressed.

  Furthermore, a static elimination sequence for neutralizing the substrate G may be incorporated in the above embodiment. Examples of the charge removal include generating plasma in the chamber 2 and increasing the pressure in the chamber 2. For example, a neutralization sequence for neutralizing the substrate G can be incorporated between Step 1 and Step 2 or in parallel with Step 9 to Step 12.

  DESCRIPTION OF SYMBOLS 1 ... Plasma etching apparatus, 2 ... Chamber, 3 ... Mounting stand, 3a ... Mounting surface, 4 ... Gas hole, 5 ... Inert gas supply pipe, 6 ... Shower head, 7 ... High frequency power supply, 8 ... Process gas supply pipe DESCRIPTION OF SYMBOLS 9 ... Exhaust pipe, 10 ... Loading / unloading port, 11 ... Gate valve, 12 ... Insertion hole, 13 ... Lifter pin, 14 ... Control part, 15 ... Pressure adjustment valve, 16 ... Inert gas supply mechanism, 100, 101 ... A gap formed between the mounting surface and the back surface of the substrate.

Claims (16)

Before detaching the object to be processed from the mounting table on which the object is to be mounted, it is detected whether the object to be processed is adsorbed on the mounting table. A method for eliminating adsorption detection,
(1) supplying a fluid at a predetermined adsorption determination pressure from the mounting surface of the mounting table to the back surface of the object to be processed;
(2) a step of detecting a flow rate of the fluid when a predetermined adsorption determination time has elapsed after starting to supply fluid at the adsorption determination pressure;
(3) a step of determining whether or not the flow rate of the fluid detected in the step (2) is equal to or lower than a predetermined adsorption determination flow rate;
(4) If the flow rate of the fluid is equal to or lower than the adsorption determination flow rate as a result of the determination in the step (3), the pressure at which the fluid is supplied to the back surface of the workpiece is higher than the adsorption determination pressure. A process for reducing pressure,
A method for eliminating adsorption detection, comprising: (5) The fluid supplied to the back surface of the object to be processed until a predetermined adsorption canceling determination time elapses after the pressure for supplying the fluid to the back surface of the object to be processed is the adsorption canceling pressure. A step of determining whether the flow rate is equal to or higher than a predetermined adsorption elimination determination flow rate
The adsorption detection elimination method according to claim 1, further comprising:   The suction detection cancellation method according to claim 2, wherein a value of the adsorption cancellation determination flow rate is smaller than a value of the adsorption determination flow rate. As a result of the determination in the step (5), when the flow rate of the fluid is equal to or higher than the adsorption elimination determination flow rate,
(6) It is determined whether or not the flow rate of the fluid supplied to the back surface of the object to be processed is equal to or higher than the adsorption determination flow rate, and whether or not the adsorption of the object to be processed to the mounting table is eliminated. A step of determining
The adsorption detection elimination method according to claim 2, further comprising: As a result of the determination in the step (5), when the adsorption is not solved, or as a result of the redetermination in the step (6), the adsorption is not solved,
(7) A step of driving a lifter pin that lifts the peripheral edge of the object to be processed, lifting only the peripheral edge of the object to be processed within the allowable bending range of the object to be processed, and separating the object from the mounting table.
The adsorption detection eliminating method according to claim 4, further comprising:   6. The suction detection elimination method according to claim 5, wherein, in the step (7), peripheral portions of the object to be processed that drive and lift the lifter pins are four corners of the object to be processed.   The suction detection elimination method according to claim 5, wherein in the step (7), the peripheral portion of the object to be processed that drives and lifts the lifter pin is two opposite sides of the object to be processed. .   In the step (7), the operation of lifting only the peripheral portion of the object to be processed by the lifter pin is repeatedly performed for a predetermined time limit. Adsorption detection elimination method according to item.   The adsorption detection elimination method according to any one of claims 5 to 8, wherein the step (7) is performed while neutralizing the object to be processed.   In the step (7), it is determined again whether or not the flow rate of the fluid supplied to the back surface of the object to be processed is equal to or less than the adsorption determination flow rate, and the adsorption of the object to be processed is eliminated. It is determined whether it was carried out, The adsorption | suction detection elimination method as described in any one of Claims 5 thru | or 9 characterized by the above-mentioned. As a result of the determination in the step (3), when the adsorption is not performed, or as a result of the re-determination in the step (6), when the adsorption is eliminated, or as a result of the re-determination in the step (7), the adsorption is eliminated. If
The suction detection elimination method according to claim 10, wherein the object to be processed is detached from the mounting table using the lifter pin.   The re-determination in the step (7) is continued until a predetermined time limit, and the process is stopped when the adsorption of the object to be processed is not eliminated by the time limit. The adsorption detection elimination method according to claim 10 or 11. When the fluid is supplied from the mounting surface of the mounting table to the back surface of the object to be processed, when the swelling of the central portion of the object to be processed reaches the limit,
(8) The method further comprises the step of driving the lifter pin to lift the outside of the object to be processed and peeling the outside of the object to be processed from the mounting table within the allowable deflection range of the object to be processed. The adsorption detection elimination method according to any one of claims 1 to 12, characterized in that: Between the step (1) and the step (2),
(9) The adsorption detection elimination method according to any one of claims 1 to 13, further comprising a static elimination step of neutralizing the object to be processed. A mounting table for mounting the object to be processed;
A lifter pin configured to protrude and retract from the mounting surface of the mounting table, and lift and lower the substrate above the mounting surface of the mounting table;
A plurality of gas holes provided on the mounting surface of the mounting table;
A gas supply pipe connected to the plurality of gas holes;
A gas supply mechanism for supplying gas to the gas supply pipe;
A pressure adjusting mechanism that is provided in the gas supply pipe and adjusts the flow rate of the gas supplied to the gas supply pipe so that the pressure in the gas supply pipe becomes a set pressure;
A control mechanism for controlling at least one of the pressure adjustment mechanism and the lifter pin so as to execute the adsorption detection elimination method according to any one of claims 1 to 14.
A processing apparatus comprising: A computer-readable storage medium that operates on a computer and stores a control program for controlling a processing device,
15. A computer-readable storage medium characterized in that the control program controls the processing device so that the adsorption detection elimination method according to any one of claims 1 to 14 is performed at the time of execution.

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