CN106486411A - Substrate board treatment, the position detection of lifter pin, regulation and method for detecting abnormality - Google Patents

Abstract

The present invention provides the substrate board treatment of the height and position that can be properly positioned lifter pin at short notice.The driving instruction of motor is sent to the drive division of lifting pin assembly from the drive control part (51) of control unit (50).Receive the driving instruction, motor rises lifter pin and driven with rotary speed corresponding with command pulse and torque rotation driving.Abut test section (53) and monitor that be output valve in servo amplifier.For example, when the absolute value in the delay pulse of the aggregate-value of the command pulse as the offset counter in servo amplifier exceedes threshold value, judge that the front end of lifter pin is abutted with the lower surface of mounting thing.

Description

Substrate processing device, position detection, adjustment and abnormality detection method of lift pins

technical field

The present invention relates to a substrate elevating device for elevating a substrate such as a glass substrate for a flat panel display (FPD), a substrate processing device for processing a substrate, a height position detection method and a height position adjustment method of a lift pin, and an abnormality of the lift pin Detection method.

Background technique

In a substrate processing apparatus for performing processes such as etching and film formation on a substrate, a plurality of lift pins capable of protruding and sinking relative to the substrate mounting surface are provided on a mounting table on which the substrate is mounted. Substrate transfer is performed by raising and lowering these lift pins. During processing of the substrate, the lift pins are accommodated in holes formed in the stage.

Regarding the control of lift pins, a semiconductor substrate processing apparatus is proposed in Patent Document 1, which includes: a monitoring unit that constantly monitors changes in the load applied to a motor that drives the lift pins; The judging part that judges that the operation of the lift pin is abnormal when the variation of the value exceeds the rated value.

In addition, Patent Document 2 proposes the following technology: when the semiconductor substrate is electrostatically adsorbed by the electrostatic chuck, the tip of the lift pin is raised only by a predetermined amount from the adsorption surface of the electrostatic chuck, and the technology is based on the motor driving the lift pin. The motor torque signal of the driver is used to detect the adsorption state of the semiconductor substrate to the electrostatic chuck.

Furthermore, regarding the control of a motor in a semiconductor manufacturing apparatus, Patent Document 3 proposes a technique of constantly monitoring pulses generated by an encoder even when the motor is in a non-driving state. In addition, Patent Document 4 proposes a technique in which a current obtained by proportionally integrating the deviation is passed through the AC servo motor before the passive body reaches the target position, and a current proportional to the deviation is passed through the AC servo motor when the passive body reaches the target position. proportional to the value of the current.

prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 2010-278271 (FIG. 4 etc.)

Patent Document 2: Japanese Patent Laid-Open No. 2008-277706 (Scope of Claims, etc.)

Patent Document 3: Japanese Patent Laid-Open No. 2000-152676 (Scope of Claims, etc.)

Patent Document 4: Japanese Patent Application Laid-Open No. 9-201083 (FIG. 2 etc.)

Contents of the invention

The technical problem that the invention wants to solve

Glass substrates for FPDs tend to increase in size and become thinner in recent years. In order to stably support a large and thin glass substrate, it is necessary to increase the number of lift pins. Therefore, in the prior art, lift pins are arranged while avoiding the in-plane productization area of the glass substrate (the area where components, wiring, etc. are placed), but in the future there will also be a place under the in-plane productization area of the glass substrate. Configure the demand for lift pins. However, when the lift pins are arranged below the production area, when the position of the lift pins is too high, the lift pins come into contact with the substrate during processing of the substrate, causing process unevenness. On the other hand, when the position of the lift pin is too low during the processing of the substrate, an electric field falls into the gap between the substrate and the tip of the lift pin, causing processing unevenness such as etching spots. Therefore, it is very important to correctly grasp the position of the lift pin to ensure the reliability of the product.

However, there has not been a solution to automatically grasp the position of the lift pins. Instead, the operator measures the position of each lift pin using a measuring device such as a dial indicator. Therefore, it takes a long time for positioning, and there are devices problem of prolonged downtime.

An object of the present invention is to provide a substrate processing apparatus capable of accurately grasping the height positions of lift pins in a short time.

Technical Solutions for Solving Technical Issues

The substrate processing apparatus of the present invention includes: a mounting table on which a substrate is mounted; a substrate elevating device including lift pins provided so as to protrude and sink relative to the substrate supporting surface of the mounting table to transfer the substrate; a servo motor of a drive unit for raising or lowering the lift pin; and a control unit for controlling the above-mentioned substrate lifting device. Furthermore, in the substrate processing apparatus of the present invention, the control unit includes a contact detection unit that monitors an output value from a motor driver of the servo motor and detects contact between the tip of the lift pin and the object placed on the substrate support surface. The height position of the abutment of the lower surface.

In addition, in the substrate processing apparatus of the present invention, a droop pulse which is a difference between a command pulse and a feedback pulse of the servo motor may be monitored as the output value, or a torque value of the servo motor may be monitored as the output value. monitor.

In addition, in the substrate processing apparatus of the present invention, the control unit may further include a height position adjustment unit that lowers the lift pin by a predetermined amount after the tip of the lift pin comes into contact with the lower surface of the load.

In addition, in the substrate processing apparatus of the present invention, the control unit may further include an abnormality detection unit based on the amount of movement until the tip of the lift pin comes into contact with the lower surface of the load or the amount of movement until the contact stops. The movement amount detects the abnormality of the lift pin mentioned above.

Furthermore, in the substrate processing apparatus of the present invention, the control unit may further include a drive speed setting unit that sets a drive speed of the lift pins. In this case, the driving speed setting unit may set the following speeds: a first driving speed for driving the lift pins for transferring the substrate; The lift pin is driven at a second driving speed lower than the first driving speed at a height position where the lower surface of the loaded object abuts.

The height position detection method of lift pins of the present invention comprises a stage on which a substrate is placed, a lift pin disposed so as to be able to protrude and sink relative to the substrate support surface of the stage, and a lift pin as a means of raising or lowering the lift pin. A method of detecting the height position of the above-mentioned lift pin in a substrate processing apparatus with a servo motor of a lowering drive unit. The height position detection method of the lift pin includes: an ascending step of raising the lift pin from the first height position; and a detection step of detecting the distance between the front end of the lift pin and the position of the lift pin on the basis of an output value from the motor driver of the servo motor. The abutment of the lower surface of the placed object on the above-mentioned substrate supporting surface.

The height position adjustment method of the lift pins of the present invention comprises a stage on which a substrate is placed, a lift pin disposed so as to be able to protrude and sink relative to the substrate supporting surface of the stage, and a lift pin as a means of raising or lowering the lift pin. A method of adjusting the height position of the above-mentioned lift pins in a substrate processing apparatus using a servo motor in a lowering drive unit. The height position adjustment method includes: an ascending step of raising the lift pin from the first height position; a detection step of detecting the front end of the lift pin and the position placed on the substrate support surface based on the output value of the motor driver of the servo motor. contact of the lower surface of the load; and a stop step of stopping the lift pin at the second height position when the contact is detected in the detecting step.

In addition, the method for adjusting the height position of the lift pins of the present invention may further include lowering the lift pins to the third position based on the height position at which the front ends of the lift pins contact the lower surface of the load or the second height position. Descending steps at height position.

The abnormality detection method of the lift pin of the present invention comprises a stage on which a substrate is placed, a lift pin provided so as to protrude and sink relative to the substrate supporting surface of the stage, and a drive unit for raising or lowering the above-mentioned lift pin. A method for detecting the above-mentioned abnormality of the lift pin in the substrate processing apparatus of the servo motor. The method for detecting an abnormality of the lift pin includes: an ascending step of raising the lift pin from a first height position; abutment of the lower surface of the load on the support surface; and an abnormality detection step based on the movement amount from the first height position to the height position at which the tip of the lift pin abuts the lower surface of the load, or to Abnormality of the lift pin is detected by the amount of movement to the second height position at which the lift pin stops after contact.

In the height position detection method of the lift pins, the height position adjustment method of the lift pins, and the abnormality detection method of the lift pins of the present invention, the output value may be a droop pulse that is the difference between the command pulse and the feedback pulse of the servo motor. Monitoring is performed, or the torque value of the above-mentioned servo motor is monitored as the above-mentioned output value.

In addition, in the height position detection method of the lift pins, the height position adjustment method of the lift pins, and the abnormality detection method of the lift pins of the present invention, the servo motor may be provided so that the speed can be switched to: a first driving speed for driving the lift pins; and a second driving speed for driving the lift pins in order to detect contact between the front ends of the lift pins and the lower surface of the load, which is lower than the first drive speed, according to the above-mentioned The second driving speed performs the above-mentioned rising step.

Invention effect

According to the present invention, by using the output value of the motor driver from the drive unit as an index, it is possible to quickly and automatically detect that the tip of the lift pin has reached the load with an accuracy equal to or higher than that of manual positioning using a dial indicator, for example. condition of the lower surface. Thereby, the time required for the positioning of the lift pins can be significantly shortened, so that the downtime of the apparatus can be reduced, and the efficiency of substrate processing can be improved.

Description of drawings

FIG. 1 is a schematic cross-sectional view showing an example of a plasma etching apparatus according to an embodiment of the present invention.

Fig. 2 is a block diagram showing the configuration of a drive unit of the lift pin device.

FIG. 3 is a block diagram showing a hardware configuration of a control unit.

4 is a functional block diagram showing the functions of a control unit related to the control of the lift pin device.

5 is a partial cross-sectional view of the upper portion of the mounting table showing height positions of lift pins.

Fig. 6 is a partial cross-sectional view of the upper portion of the mounting table showing another height position of the lift pin.

FIG. 7 is a diagram schematically showing temporal changes of droop pulses accumulated by a deviation counter of a servo amplifier.

8 is a flowchart showing an example of the procedure of the height position detection/adjustment method of the lift pin according to the first embodiment of the present invention.

FIG. 9 is an explanatory view showing an example of a mounted object other than a substrate.

10 is a flowchart showing an example of the procedure of the height position adjustment method of the lift pins according to the second embodiment of the present invention.

Fig. 11 is a partial cross-sectional view of the upper portion of the mounting table showing still another height position of the lift pin.

FIG. 12 is a flowchart showing an example of the procedure of a lift pin abnormality detection method according to a third embodiment of the present invention.

FIG. 13 is a diagram schematically showing temporal changes in the torque value of the servo motor.

Explanation of reference signs

50...Control section, 51...Drive control section, 51a...Drive speed setting section, 51b...Height position adjustment section, 53...Abutment detection section, 53a...Threshold storage section, 53b...Determination section , 55...abnormality detection unit, 55a...threshold storage unit, 55b...judging unit.

detailed description

Embodiments of the present invention will be described in detail below with reference to the drawings. First, a plasma etching apparatus according to one embodiment of the present invention will be described with reference to FIG. 1 . The plasma etching apparatus 100 is configured as a capacitively coupled parallel plate plasma etching apparatus for etching a rectangular substrate S for FPD. Moreover, as FPD, a liquid crystal display (LCD), an electroluminescence (Electro Luminescence: EL) display, a plasma display panel (PDP), etc. can be illustrated.

<processing container>

This plasma etching apparatus 100 has a processing container 1 formed in a rectangular cylinder shape made of aluminum, the surface of which was subjected to anodization treatment (alumite treatment). The processing container 1 is composed of a bottom wall 1a and four side walls 1b. In addition, a cover body 1c is joined to the upper portion of the processing container 1 . The lid body 1c is configured to be openable and closable by an unillustrated opening and closing mechanism. When the lid 1c is closed, the junction between the lid 1c and each side wall 1b is sealed by a sealing member (not shown), and the airtightness in the processing container 1 is maintained.

<Place>

A mounting table 3 on which a substrate S is mounted is provided in the processing container 1 . The mounting table 3 also serving as a lower electrode includes: a base material 3 a made of a conductive material such as aluminum or stainless steel (SUS); and an insulating member (not shown) covering the base material 3 a. In addition, a high-frequency power supply is connected to the base material 3a via a power supply line and a matching box, and is not shown in the figure.

Furthermore, the stage 3 has an electrostatic adsorption electrode 5 on the base material 3a. The electrostatic adsorption electrode 5 has a structure in which a first insulating layer 5 a , an electrode 5 b , and a second insulating layer 5 c are stacked in order from below. By applying a DC voltage to the electrode 5b between the first insulating layer 5a and the second insulating layer 5c via the power supply line 5e from the DC power supply 5d, the substrate S can be electrostatically adsorbed by Coulomb force, for example.

Furthermore, the mounting table 3 has a plurality of lift pin devices 7 . Depending on the area of the substrate S, for example, several to several tens of lift pin devices 7 are arranged as a substrate lifting device. Each lift pin device 7 is driven by an independent drive source. Each lift pin device 7 includes: a lift pin 7a that is inserted into a hole 3b provided in the base material 3a of the mounting table 3 from below and is disposed so as to protrude and sink relative to the substrate supporting surface of the mounting table 3; The driving part 7b of the pin 7a. In addition, as shown in FIG. 1 , when the mounting table 3 has the electrostatic adsorption electrode 5 , "the substrate supporting surface of the mounting table" means the upper surface of the electrostatic adsorption electrode 5 . The lift pins 7a support the substrate S, and the drive unit 7b moves the substrate S up and down between the substrate support surface of the stage 3 and a position away from the substrate support surface. The detailed structure of the lift pin device 7 will be described later.

<Gas supply mechanism>

Shower head 9 functioning as an upper electrode is provided above mounting table 3 . The shower head 9 is supported by the upper lid body 1c of the processing container 1 . Shower head 9 is formed in a hollow shape, and gas diffusion space 9a is provided inside. In addition, a plurality of gas discharge holes 9 b for discharging etching gas as a processing gas are formed on the lower surface of the shower head 9 (the surface facing the mounting table 3 ). The shower head 9 is grounded, and constitutes a pair of parallel plate electrodes together with the mounting table 3 .

A gas introduction port 11 is provided near the upper center of the shower head 9 . A gas supply pipe 13 for supplying a processing gas is connected to the gas introduction port 11 . The other end side of the gas supply pipe 13 is connected to a gas supply source 15 for supplying an etching gas or the like as a processing gas, for example.

<Exhaust Mechanism>

Exhaust openings 1d (only two are shown) are formed at a plurality of positions on the bottom wall 1a near the four corners of the processing chamber 1 as through openings. An exhaust pipe 17 is connected to each exhaust opening 1d. The exhaust pipe 17 is connected to an exhaust device 19 having a vacuum pump such as a turbomolecular pump, for example. The inside of the processing container 1 can be evacuated to a predetermined reduced pressure atmosphere by the exhaust device 19 .

<Board loading and unloading port>

The side wall 1b of the processing container 1 is provided with an opening 1e for substrate transfer. The opening 1e for substrate transfer is opened and closed by a gate valve 21, and the substrate S can be transferred between the opening 1e and an adjacent transfer chamber (not shown).

<Lift pin device>

Next, the lift pin device 7 will be described in detail. As described above, one lift pin device 7 includes: lift pins 7a that perform lift-up displacement to transfer substrates S; and drive units 7b that drive lift pins 7a. FIG. 2 is a block diagram showing the configuration of the drive unit 7b. The driving unit 7 b is a servo motor including a pulse generating unit 31 , a servo amplifier 33 , a motor 35 , and an encoder 37 . The servo amplifier 33 is provided with a deviation counter 33 a.

The pulse generation unit 31 is, for example, a programmable logic controller (PLC), and generates command pulses for driving the motor 35 under the control of a higher-level control unit 50 (described later), and inputs them to the servo amplifier 33 .

The servo amplifier 33 outputs a command signal for driving the motor 35 to the motor 35 and receives a feedback signal generated by driving the motor 35 to control the output torque, rotational speed, position, etc. of the motor 35 . In addition, the servo amplifier 33 outputs various parameters based on the command signal and the feedback signal to the control unit 50 (described later). The servo amplifier 33 has a deviation counter 33a and a D/A conversion unit not shown. The command pulses from the pulse generator 31 are cumulatively counted in the deviation counter 33a.

The motor 35 is connected to the lift pin 7a, and when a command pulse is input to the servo amplifier 33, it is rotationally driven at a rotation speed and torque corresponding to the command pulse to drive the lift pin 7a up and down.

The encoder 37 generates a feedback pulse proportional to the rotation speed of the motor 35 when the motor 35 rotates, and feeds it back to the servo amplifier 33 .

In the lift pin device 7 having the above configuration, based on the command from the control unit 50 , the pulse generating unit 31 generates a command pulse for driving the motor 35 and inputs it to the servo amplifier 33 . The command pulses are accumulated in the deviation counter 33a in the servo amplifier 33, and the accumulated value of the command pulses (dripping pulses) is converted into a DC analog voltage to rotate the motor 35 and drive the lift pin 7a up and down. When the motor 35 rotates, a feedback pulse proportional to the rotational speed of the motor 35 is generated by the encoder 37 . This feedback pulse is fed back to the servo amplifier 33, and the droop pulse of the deviation counter 33a is subtracted.

<control department>

Each component of the plasma etching apparatus 100 is connected to the control unit 50 and is collectively controlled by the control unit 50 . The control unit 50 is a module controller (Module Controller) that controls each component of the plasma etching apparatus 100 . The control unit 50 is connected to an I/O module not shown. This I/O module has a plurality of I/O parts, and is connected to each terminal of the plasma etching apparatus 100 . The I/O section is provided with I/O ports for controlling input and output of digital signals, analog signals, and serial signals. Control signals for each terminal are output from the I/O section. In addition, output signals from each terminal are respectively input to the I/O section. In the plasma etching apparatus 100, as a terminal connected to the I/O unit, for example, the lift pin device 7, the exhaust device 19, and the like can be mentioned.

An example of the hardware configuration of the control unit 50 will be described with reference to FIG. 3 . The control unit 50 includes a main control unit 101 , an input device 102 such as a keyboard and a mouse, an output device 103 such as a printer, a display device 104 , a storage device 105 , an external interface 106 , and a bus 107 connecting them. The main control unit 101 has a CPU (Central Processing Unit) 111 , a RAM (Random Access Memory) 112 and a ROM (Read Only Memory) 113 . The form of the storage device 105 is not limited as long as it can store information, and is, for example, a hard disk device or an optical disk device. In addition, the storage device 105 records information on a computer-readable storage medium 115 and reads information from the storage medium 115 . The form of the storage medium 115 is not limited as long as it can record information, and is, for example, a hard disk, an optical disk, or a flash memory. The storage medium 115 may be a storage medium storing the recipe of the substrate processing method of this embodiment.

In control unit 50 , CPU 111 executes a program stored in ROM 113 or storage device 105 using RAM 112 as a work area, thereby performing plasma etching on substrate S in plasma etching apparatus 100 of the present embodiment.

FIG. 4 is a functional block diagram showing functions related to the control of the lift pin device 7 in the control unit 50 . As shown in FIG. 4 , the control unit 50 has a drive control unit 51 , a contact detection unit 53 , and an abnormality detection unit 55 .

The drive control section 51 performs drive control of the lift pin device 7 , specifically, controls such that vertical displacement of the lift pin 7 a relative to the drive section 7 b is driven and stopped. Moreover, the drive control part 51 has the drive speed setting part 51a and the height position adjustment part 51b. The drive speed setting unit 51a sets the speed at which the lift pin 7a moves up and down. In this embodiment, the following speeds are switchably set: the first driving speed for driving the lift pins 7a for transferring the substrate S; The second drive speed of the lift pin 7a is driven at the height position where the lower surface of the lift pin 7a abuts. The second driving speed is set to be lower than the first driving speed, and the lift pin 7 a is raised and lowered at about 1 mm/min to 10 mm/min, for example. Hereinafter, when the lift pin 7a is driven up and down to transfer the substrate S, it will be referred to as a "delivery mode". When the lift pin 7a is driven up and down according to the position, it is called "detection mode". In addition, in the detection mode of the present embodiment, the lift pin 7a is driven at a second driving speed that is lower than that in the transfer mode, but instead of the driving speed, other parameters such as speed gain and position gain may be set to each other. Each mode is set to a different value. In addition, the height position adjustment unit 51b can store the movement amount when the lift pin 7a is further driven to adjust the height position from the height position at which the tip of the lift pin 7a comes into contact with the lower surface of the load and stops (that is, the displaced lift pin 7a). 7a travel amount). In addition, a mounted object means the board|substrate S or the load 60 mentioned later (refer FIG. 9).

The contact detection unit 53 detects the height position at which the tip of the lift pin 7a contacts the lower surface of the load. Specifically, the contact detection unit 53 monitors the output value from the servo amplifier 33 as a motor driver, compares the output value with a preset threshold value, and determines whether the tip of the lift pin 7a is in contact with the lower surface of the load. catch. The contact detection unit 53 includes a threshold storage unit 53a that stores the above threshold, and a determination unit 53b that performs the above determination based on the threshold. In addition, the threshold storage unit 53 a may be provided in the storage device 105 . Here, the "output value from the servo amplifier 33" may be a parameter that fluctuates when the tip of the lift pin 7a comes into contact with the lower surface of the load, and may be a parameter based on a command signal to the motor 35 or based on a parameter from the motor. Any one of 35 parameters of the feedback signal. In addition, the output value may be, for example, a direct parameter output from the motor 35 side, or a binary parameter obtained through arithmetic processing on the direct parameter. Specific examples of output values include parameters such as droop pulses that are integrated values of command pulses in the servo amplifier 33 , torque values of the motor 35 , speed of the motor 35 , and temporal changes (speed waveforms) of the motor 35 . Among the above-mentioned output values, the droop pulse responds sensitively to the load of the motor 35, and therefore, it is most preferable as an index of contact detection of the lift pin 7a.

The abnormality detection unit 55 cooperates with the contact detection unit 53 to detect an abnormality of the lift pin. Here, the abnormality of the lift pin 7a mainly refers to cutting, bending, etc. of the tip of the lift pin 7a. The abnormality detection unit 55 is based on the height position at which the tip of the lift pin 7a is in contact with the lower surface of the load detected by the contact detection unit 53 and the height position of the lift pin 7a before reaching the height position obtained by the encoder 37 . The movement amount (stroke amount) from the lowered position is used to detect the abnormality of the lift pin. Specifically, it is determined that the lift pin 7 a is abnormal when the movement amount before the tip of the lift pin 7 a abuts against the lower surface of the load exceeds a threshold value. The abnormality detection unit 55 includes a threshold storage unit 55a that stores the above threshold, and a determination unit 55b that performs the above determination based on the threshold. In addition, the threshold storage unit 55 a may be provided in the storage device 105 .

The above processing of the control unit 50 can be realized by the CPU 111 executing the software (program) stored in the ROM 113 or the storage device 105 using the RAM 112 as a work area. In addition, the control unit 50 also has other functions, but description thereof is omitted here.

[How to detect the height position of the lift pin / How to adjust the height position of the lift pin]

Next, the height position detection method and the height position adjustment method of the lift pin 7a of the plasma etching apparatus 100 will be described.

<First Embodiment>

5 and 6 are partial cross-sectional views of the upper portion of the mounting table 3 including the lift pin 7a. Two lift pins 7a are representatively shown in FIGS. 5 and 6 .

First, FIG. 5 shows the position where the lift pin 7a descends the most (the position where the descending range is the largest). At the position where the drop range is the largest, the front end of the lift pin 7a is completely buried in the hole 3b. The maximum drop range corresponds to the first height position. In addition, although not shown in the figure, at the most raised position (maximum ascent position), the tip of the lift pin 7a protrudes from the substrate supporting surface of the mounting table 3 . The transfer of the board|substrate S is performed at the position of this rising range maximum, or its vicinity.

6 shows a state in which the lift pin 7a is raised in the detection mode from the state of FIG. 5 and the tip of the lift pin 7a abuts on the lower surface of the substrate S electrostatically attracted to the electrostatic adsorption electrode 5 . The position shown in FIG. 6 is called a "contact position". The height position detection method of the lift pins in this embodiment is to raise the lift pin 7a from the position with the maximum drop range in the detection mode, and detect the height position of the lift pin 7a based on the change of the dwell pulse when the lift pin 7a reaches the contact position. (i.e. reaching the abutment position).

FIG. 7 schematically shows the temporal change of the accumulated pulses in the deviation counter 33a of the servo amplifier 33 in the drive unit 7b of the lift pin device 7. As shown in FIG. FIG. 7 shows a state where the tip of the lift pin 7a reaches the contact position at time t, and then the driving is stopped. The droop pulse, which is the difference between the command pulse and the feedback pulse, fluctuates greatly when the motor 35 starts to rotate, but after the time t0, when the lift pin 7a is raised at a constant speed, as shown in FIG. 7, it maintains a fluctuation within a certain range. . However, when the lift pin 7a reaches the contact position at time t, the absolute value of the droop pulse greatly exceeds the threshold Th (here, the threshold Th refers to an absolute value. The same applies hereinafter) and fluctuates. Thereby, by detecting the fluctuation of this droop pulse, the height position of the lift pin 7a can be detected.

8 is a flow chart showing an example of the procedure of the height position adjustment method of the lift pins according to the first embodiment. The method for adjusting the height position of the lift pin in this embodiment can include the process from step S1 to step S5 shown in FIG. 8 . Here, step S1 to step S4 constitute the height position detection method of the lift pin of the first embodiment. Hereinafter, when the method of detecting the height position of the lift pins and the method of adjusting the height position of the lift pins are not distinguished in the first embodiment, they are referred to as "the method of detecting/adjusting the height position of the lift pins".

First, in step S1 , in the driving speed setting unit 51 a of the driving control unit 51 of the control unit 50 , the driving speed of the lift pins is set in the detection mode. As described above, in the detection mode, the lift pins 7a are driven at the second driving speed which is lower than the driving speed in the handover mode. By driving the lift pin 7a at the second driving speed, it is possible to reliably and accurately detect the height position while preventing accidents such as breakage of the lift pin 7a.

Next, in step S2 , a drive command for the motor 35 is issued from the drive control unit 51 of the control unit 50 to the drive unit 7 b of the lift pin device 7 . Receiving the drive command, the pulse generator 31 generates a command pulse for driving the motor 35 and inputs it to the servo amplifier 33 . When a command pulse is input to the servo amplifier 33, the motor 35 is rotationally driven at a rotational speed and torque corresponding to the command pulse, and the lift pin 7a is driven upward at the second speed from the position of the maximum descending range shown in FIG. 5 . Step S2 corresponds to an ascending step.

In step S3, while the lift pin 7a is rising, the contact detection part 53 of the control part 50 monitors the stagnation pulse of the deviation counter 33a. Specifically, the determination unit 53b of the contact detection unit 53 acquires the value of the staying pulse of the deviation counter 33a. Then, in step S4, the absolute value of the stagnant pulse acquired in step S3 is compared with a preset threshold Th, and it is judged whether or not the absolute value of the stagnant pulse exceeds the threshold Th. These steps S3 and S4 correspond to a detection step. The detection step is performed in parallel with the rising step of step S2. Here, during a certain period of time after the start of rotation of the motor 35 , the droop pulse fluctuates greatly (see 0 to t0 on the horizontal axis in FIG. 7 ), so it is preferable to exclude it from the comparison object in step S4. At this time, the elapsed time from the drive command in step S2 to the above-mentioned t0 can be known in advance, and this time can be removed from the comparison object, or the maximum deviation of the dwell pulse can be detected through monitoring, and the fluctuation converges within a certain range as trigger, and perform the comparison in step S4.

The threshold Th used in the determination of step S4 can be, for example, a value stored in the threshold storage unit 53 a of the contact detection unit 53 . The threshold Th is set based on, for example, experimentally obtained data, in accordance with the driving speed and driving torque of the lift pin 7a in the detection mode. In addition, the threshold Th can also be set by inputting from the input device 102 .

When it is judged in step S4 that the absolute value of the droop pulse exceeds the threshold value Th (Yes), it is detected that the tip of the lift pin 7 a has reached the contact position with the lower surface of the substrate S. At this time, in the next step S5, a command to stop the motor 35 is issued from the drive control unit 51 of the control unit 50 to the drive unit 7b of the lift pin device 7, and the drive of the lift pin 7a is stopped. This step S5 corresponds to the stopping step. Let the height position at the time of stopping the lift pin 7a in this way be a "detection stop position". This detection stop position corresponds to the "second height position". Due to the time lag in the control of the lift pin device 7, the detection stop position is a position slightly raised from the strict contact position, but may be the same height position as the contact position.

On the other hand, when it is judged in step S4 that the absolute value of the stagnant pulse does not exceed the threshold Th (No), in the contact detection unit 53, the monitoring of the stagnant pulse in step S3 and the determination of the threshold Th in step S4 are repeated. . Now, step S3 and step S4 continue to carry out, until according to the stop command that is not included in this process, for example, based on the stop command of the height position of the lift pin 7a obtained from the encoder 37 and the upper limit value of the predetermined height position, the lift The ascent of pin 7a stops.

The above process from step S1 to step S4 and step S5 can be performed on each lift pin device 7 . At this time, the above-described process can be performed simultaneously for a plurality of lift pin devices 7 . In addition, in this embodiment, by comparing the absolute value of the dwell pulse with the threshold value Th, it is detected that the tip of the lift pin 7a is in contact with the lower surface of the load. In some cases, it is also possible to use the original positive or negative threshold value (positive value or negative value) instead of the absolute value of the droop pulse for comparison.

According to the method of detecting and adjusting the height position of the lift pin in this embodiment, by using the stagnation pulse of the deviation counter 33a in the drive unit 7b as an index, it is possible to achieve the same or higher accuracy than manual positioning using a dial-type indicator, for example. , quickly and automatically detect that the front end of the lift pin 7a has reached the contact position. Accordingly, even when the lift pins 7a are disposed below the productization area of the substrate S, it is possible to ensure reliability of the product while avoiding processing unevenness such as etching spots, for example. In addition, the height position of the lift pin 7a can be automatically detected and adjusted without manual operation by the operator, thereby greatly shortening the time required for positioning the lift pin 7a, reducing the downtime of the device, and improving the efficiency of substrate processing. efficiency.

When using a substrate S as a mounted object, the height position of each substrate S may be detected or adjusted each time the substrate S to be processed is replaced on the stage 3, or the height position may be detected or adjusted every time a plurality of substrates S are replaced. The number of detection or adjustment of the height position. In this way, during the actual substrate processing, the height position at which the lift pins 7a contact the lower surface of the substrate S is periodically detected or adjusted, thereby extremely reducing the possibility of processing unevenness such as etching spots. , to ensure product reliability. In the height position detection and adjustment method of the lift pins according to the present embodiment, the more abruptly the dwell pulse fluctuates, the more precisely the contact between the lift pins 7 a and the substrate S can be detected. Therefore, it is preferable to apply a stress to the substrate S that can sufficiently resist the load of the ascending lift pin 7a. Therefore, it is more preferable to detect fluctuations in the dwell pulse more easily by performing the above steps S1 to S5 in a state where the substrate S is attracted by, for example, the electrostatic adsorption electrode 5 .

In addition, instead of the board|substrate S, as a mounted object, it may carry out in the state which arrange|positioned the load 60, such as the block with predetermined weight provided so that the hole 3b may be covered, as shown in FIG. In particular, when the electrostatic adsorption is not used or the mounting table 3 does not have the electrostatic adsorption electrode 5, by replacing the substrate S, a load 60 having a mass capable of sufficiently resisting the load of the rising lift pin 7a can be detected with high accuracy. Or adjust the height position where the lifting pin 7a abuts against the load 60 .

<Second Embodiment>

10 is a flow chart showing another example of the procedure of the height position adjustment method of the lift pins according to the second embodiment. Fig. 11 is a partial cross-sectional view of the upper portion of the mounting table 3 including the lift pin 7a. Two lift pins 7 a are representatively shown in FIG. 11 . The method for adjusting the height position of the lift pin in this embodiment includes the process of step S11 to step S17. Among them, Step S11 to Step S15 are the same as Step S1 to Step S5 in FIG. 8 , so description thereof will be omitted.

The height position adjustment method of the lift pins of this embodiment includes starting from the stopped state (detection of the stop position) after the tip of the lift pin 7a abuts against the lower surface of the substrate S, and further adjusting the position of the lift pin 7a to position the lift pin 7a. The lift pin 7a is additionally driven.

In step S15 of FIG. 10 , the tip of the lift pin 7 a reaches the detection stop position in a state where the lift drive of the lift pin 7 a is stopped in accordance with the stop command of the motor 35 . That is, the front end of the lift pin 7a is in contact with the lower surface of the substrate S. As shown in FIG. Then, in the next step S16, for example, as shown in FIG. 11 , the tip of the lift pin 7a is slightly lowered from the detection stop position, and moved to a standby position which is a height position at which the lift pin 7a stands by during processing. This standby position corresponds to the third height position. The movement amount (stroke amount) when the lift pin 7a is driven downward from the detection stop position to the standby position is determined based on the height data of the standby position stored in the height position adjustment unit 51b of the drive control unit 51 . This amount of movement can be grasped and controlled by the encoder 37 . The standby position can be set at a height that does not adversely affect the processing of the substrate S based on, for example, experimentally obtained data corresponding to the processing content of the substrate S, and is preferably in the range of about 0.05 to 1 mm based on the detection stop position. The height position where the lift pin 7a is lowered. In addition, this movement amount can be set by inputting from the input device 102 .

In this way, by adjusting the height position of the front end of the lift pin 7a to the standby position slightly lowered from the height of the lower surface of the substrate S as the detection stop position, when the lift pin 7a is arranged below the production area of the substrate S, the Processing unevenness such as etching spots can be reliably prevented. In addition, the standby position is set to be higher than the maximum drop width position and lower than the detection stop position and contact position.

Next, in step S17, the drive control unit 51 of the control unit 50 issues a command to stop the motor 35 to the drive unit 7b of the lift pin device 7, and the drive of the lift pins 7a is stopped.

Through the above-described procedure, in the present embodiment, the tip of the lift pin 7a is displaced to the standby position based on the detected stop position. Therefore, for example, even when the length of the lift pin 7a is shortened to some extent by cutting, bending, etc., the height position of the tip can be controlled to the standby position. Thus, even if the lift pins 7a are cut or bent, it is possible to prevent the positions of the tips of the lift pins 7a that are at the standby position during the processing of the substrate S from being uneven, and to avoid processing defects such as etching spots. The occurrence of uniformity ensures the reliability of the product.

Experimental results for confirming the effects of the present invention will be described. According to the procedure of step S11 to step S17 shown in FIG. 10 , in the state where the object is placed on the substrate support surface of the stage 3 , the lift pin device 7 is raised from the position with the largest descending range to the contact position, and the detection stops. After the position stops, further lower it to the standby position. In addition, in step S16, the amount of movement from the detection stop position to the standby position is set to 0.05 mm. In this process, the substrate support surface of the stage 3 is measured, and the detection stop position and standby position are measured using a dial indicator (model 1160T manufactured by Mitutoyo Corporation, 1 scale is 0.01mm) with the object removed. The height of the front end of the lift pin 7a. The results are shown in Table 1.

[Table 1]

From Table 1, it can be confirmed that, according to the procedure of step S11 to step S17 shown in FIG. 10 , the vehicle stops after contacting the loaded object, and then lowers and drives the preset movement amount from the stopped position.

Other configurations and effects of this embodiment are the same as those of the first embodiment.

[Abnormal detection method of lift pin]

Next, the abnormality detection method of the lift pin using the height position detection and adjustment method of the lift pin of the said 1st aspect is demonstrated.

<Third Embodiment>

12 is a flowchart showing an example of a procedure of a lift pin abnormality detection method according to a third embodiment of the present invention. The abnormality detection method of the lift pin of this embodiment includes the process of step S21 - step S29. Among them, Step S21 to Step S25 are the same as Step S1 to Step S5 in the first embodiment ( FIG. 8 ), and therefore description thereof will be omitted.

In step S25 of FIG. 12 , the tip of the lift pin 7 a reaches the detection stop position in a state where the lift drive of the lift pin 7 a is stopped in accordance with the stop command of the motor 35 . That is, the front end of the lift pin 7a is in contact with the lower surface of the substrate S. As shown in FIG. Next, in step S26, the determination unit 55b of the abnormality detection unit 55 obtains the movement amount (stroke amount) for displacing the lift pin 7a from the maximum descending position to the detection stop position from the encoder 37 of the drive unit 7b. Then, in step S27, the determination part 55b compares the movement amount acquired in step S26 with the preset threshold value, and determines whether the movement amount exceeds a threshold value. Here, as the threshold value used for determination, for example, a value stored in the threshold value storage unit 55 a of the abnormality detection unit 55 can be used. The threshold value is set by the threshold value storage unit 55 a based on data obtained through experiments, for example, based on the movement amount of the lift pin 7 a when it is normal. In addition, the threshold value can also be set by inputting from the input device 102 .

If the lift pin 7a is in a normal state, the amount of movement when the lift pin 7a is displaced from the maximum drop position to the detection stop position is substantially constant. However, the amount of movement when the lift pin 7a is abnormal due to wear, such as chipping or bending, is significantly larger than the amount of movement in the normal state. Then, in step S27, when it is judged that the movement amount of the lift pin 7a exceeds the threshold value (Yes), it is detected in the next step S28 that the lift pin 7a is abnormal. At this time, for example, an error message is displayed on the display device 104 of the control unit 50 , or a maintenance message for prompting replacement of the lift pin 7 a is displayed.

On the other hand, when it is determined in step S27 that the movement amount of the lift pin 7a does not exceed the threshold value (No), it is detected in the next step S29 that the lift pin 7a has no abnormality (normal).

In this way, the abnormality detection method of the lift pins of this embodiment drives the lift pin 7a upwardly from the position with the maximum drop range, and detects, for example, the lift pin 7a according to the movement amount of the lift pin 7a when the front end abuts against the lower surface of the substrate S to reach the detection stop position. There are abnormalities such as cutting and bending of the front end. When the lift pin 7a is shortened by cutting or bending, it will adversely affect the transfer of the substrate S and cause etching spots and the like. The abnormality detection method of the lift pin of this embodiment can detect the abnormality of the lift pin 7a simply and quickly by utilizing the height position detection and adjustment method of the lift pin of the said 1st embodiment.

Other configurations and effects of this embodiment are the same as those of the first embodiment. In addition, in this embodiment, instead of displacing the movement amount when the lift pin 7a is displaced from the maximum descending width position to the detection stop position, the movement amount when shifting from the descending width maximum position to the contact position and a threshold value may be used. Compare structure. In this case, the processing of step S25 in FIG. 12 can be omitted. That is, when it is judged in step S24 that the absolute value of the dwell pulse exceeds the threshold value (Yes), then step S26 is executed, and the determination part 55b of the abnormality detection part 55 obtains the value from the encoder 37 of the drive part 7b to move the lift pin 7a from the position with the maximum drop width. The amount of movement from the position to the contact position is sufficient.

<Modification>

As a modified example of the first to third embodiments described above, a case where the torque value of the electrode 35 is monitored instead of the dwell pulse will be described. FIG. 13 is a diagram schematically showing temporal changes in the torque value of the electric motor 35 in the drive unit 7 b of the lift pin device 7 . The vertical axis of FIG. 13 is the ratio [%] of the torque value to the driving of the lift pin 7a, and the torque value becomes larger toward the upper part of the figure. FIG. 13 shows a state where the tip of the lift pin 7a reaches the contact position at time t, and then the drive is stopped. The torque value of the electrode 35 fluctuates greatly at the start of the rotation operation, but when the lift pin 7a is raised at a constant speed after time _t0 , it advances within a certain range as shown in FIG. However, when the lift pin 7 a reaches the abutment position at time t, the absolute value of the torque value largely exceeds the threshold value Th and fluctuates. Therefore, by detecting the fluctuation of the torque value, the height position of the lift pin 7a can be detected.

As described above, in the plasma etching apparatus 100, by monitoring the fluctuation of the torque value of the motor 35, the method of detecting the height position of the lift pin (first embodiment) and the control of the lift pin can be implemented similarly to the case of monitoring the droop pulse. Height position adjustment method (second embodiment) and lift pin abnormality detection method (third embodiment). In these modified examples, the "retention pulse accumulated in the deviation counter 33a" in the first to third embodiments described above is replaced with "torque value". In addition, the threshold Ta of the torque value used for determination in the modified example is set according to the driving speed and driving torque of the lift pin 7 a in the detection mode, for example, based on experimentally obtained data. In addition, the torque value can be detected as, for example, a torque current, a torque voltage, or the like.

As mentioned above, although the embodiment of this invention was described in detail for illustration, this invention is not limited to the said embodiment, Various deformation|transformation is possible. For example, the present invention is not limited to a substrate processing apparatus that processes an FPD substrate, but is also applicable to a substrate processing apparatus that processes a semiconductor wafer, for example.

In addition, the plasma etching apparatus is not limited to the parallel plate type shown in FIG. 1 , and, for example, a plasma etching apparatus using microwave plasma, a plasma etching apparatus using inductively coupled plasma, or the like can be used. In addition, the present invention is not limited to a plasma etching device, and can also be applied to a plasma processing device for other processing purposes such as a plasma ashing device, a plasma CVD film forming device, a plasma diffusion film forming device, and the like. It can also be applied to a substrate processing apparatus for processing other than plasma processing.

Furthermore, for example, the abnormality detection method of the lift pin of the third embodiment may be combined with the height position adjustment method of the second embodiment. For example, steps S26 to S29 in the third embodiment ( FIG. 12 ) may be executed after implementing the procedures in steps S11 to S17 in the second embodiment ( FIG. 10 ). In addition, for example, when it is confirmed in step S29 of the third embodiment ( FIG. 12 ) that the lift pin 7 a is normal (normal), steps S16 to S17 of the second embodiment ( FIG. 10 ) may be executed.

In addition, in the contact detection part 53, various output values from the deviation counter 33a can be monitored simultaneously. For example, the contact detection unit 53 can monitor both the dwell pulse and the torque value, and determine whether the tip of the lift pin 7a is in contact with the lower surface of the load based on the results of both. In addition, in the above-mentioned embodiment, the example in which the servo motor is used as the drive unit 7b was given, but in the case of monitoring only the torque value, it is not limited to this, and a form other than the torque value output from the motor driver can also be used. Motors (such as stepping motors, etc.).

Claims (20)

1. a kind of substrate board treatment, it is characterised in that include：

The mounting table of mounting substrate；

Substrate lifting device, it include to be arranged to project with respect to the substrate supporting face of the mounting table and submerge and carry out The lifter pin of the handing-over of the substrate and the servomotor as the drive division for rising or falling the lifter pin；With

Control the control unit of the substrate lifting device,

The control unit includes to abut test section, and which monitors the output valve of the motor driver from the servomotor, The height and position that the front end for detecting the lifter pin is abutted with the lower surface of the mounting thing for being placed in the substrate supporting face.

2. substrate board treatment as claimed in claim 1, it is characterised in that：

To carry out as the command pulse of the servomotor and the delay pulse of the difference of feedback pulse as the output valve Monitor.

3. substrate board treatment as claimed in claim 1, it is characterised in that：

The torque value of the servomotor is monitored as the output valve.

4. substrate board treatment as claimed in claim 1, it is characterised in that：

The control unit also includes height and position adjustment portion, and which is supported with the lower surface of the mounting thing in the front end of the lifter pin After connecing, the lifter pin is made to decline ormal weight.

5. substrate board treatment as claimed in claim 1, it is characterised in that：

The control unit also includes abnormity detection portion, and which is supported based on the lower surface to the front end of the lifter pin with the mounting thing Amount of movement being connected in amount of movement only or stopping to after abut, detects the exception of the lifter pin.

6. the substrate board treatment as any one of Claims 1 to 5, it is characterised in that：

The control unit also includes the actuating speed configuration part of the actuating speed for setting the lifter pin.

7. substrate board treatment as claimed in claim 6, it is characterised in that：

The actuating speed configuration part sets following speed：

The first actuating speed of the lifter pin is driven in order to carry out the handing-over of the substrate；With

Abut with the lower surface of the mounting thing for being placed in the substrate supporting face to detect the front end of the lifter pin Height and position and drive the lifter pin, less than first actuating speed the second actuating speed.

8. a kind of height position detection method of lifter pin, its include the mounting table of mounting substrate, be arranged to respect to The substrate supporting face of the mounting table projects and the lifter pin that shifts with submerging and as rising or falling the lifter pin The height and position of the lifter pin, the height position of the lifter pin is detected in the substrate board treatment of the servomotor of drive division Put detection method to be characterised by, including：

The up step for making the lifter pin increase from the first height and position；With

Detecting step, according to the output valve of the motor driver from the servomotor, before detecting the lifter pin Hold the abutting with the lower surface of the mounting thing for being placed in the substrate supporting face.

9. the height position detection method of lifter pin as claimed in claim 8, it is characterised in that：

To carry out as the command pulse of the servomotor and the delay pulse of the difference of feedback pulse as the output valve Monitor.

10. the height position detection method of lifter pin as claimed in claim 8, it is characterised in that：

The torque value of the servomotor is monitored as the output valve.

The height position detection method of 11. lifter pins as claimed in claim 8, it is characterised in that：

The servomotor is arranged to switch following speed：

The first actuating speed of the lifter pin is driven in order to carry out the handing-over of the substrate；With

In order to detect the front end of the lifter pin with described mounting thing lower surface abutting and drive the lifter pin, compare institute The second little actuating speed of the first actuating speed is stated,

The up step is carried out with second actuating speed.

A kind of height and position control method of 12. lifter pins, its include mounting substrate mounting table, be arranged to respect to The substrate supporting face of the mounting table projects and the lifter pin that shifts with submerging and as rising or falling the lifter pin The height and position of the lifter pin, the height position of the lifter pin is adjusted in the substrate board treatment of the servomotor of drive division Put control method to be characterised by, including：

The up step for making the lifter pin increase from the first height and position；

Detecting step, according to the output valve of the motor driver of the servomotor, detect the front end of the lifter pin with It is placed in the abutting of the lower surface of the mounting thing in the substrate supporting face；With

Detect in the detecting step when abutting, the stopping step for making the lifter pin stop in the second height and position.

The height and position control method of 13. lifter pins as claimed in claim 12, it is characterised in that：

Delay pulse of the command pulse of the servomotor with the difference of feedback pulse is monitored as the output valve.

The height and position control method of 14. lifter pins as claimed in claim 12, it is characterised in that：

The torque value of the servomotor is monitored as the output valve.

The height and position control method of 15. lifter pins as claimed in claim 12, it is characterised in that：

The servomotor is arranged to switch following speed：

The first actuating speed of the lifter pin is driven in order to carry out the handing-over of the substrate；With

In order to detect the front end of the lifter pin with described mounting thing lower surface abutting and drive the lifter pin, compare institute The second little actuating speed of the first actuating speed is stated,

The up step is carried out with second actuating speed.

The height and position control method of 16. lifter pins as claimed in claim 12, it is characterised in that also include：

The height and position abutted with the lower surface of the mounting thing with the front end of the lifter pin or second height and position are Benchmark, makes the lifter pin drop to the decline step of third height position.

A kind of 17. method for detecting abnormality of lifter pin, its are including the mounting table of mounting substrate, are being arranged to respect to described The substrate supporting face protrusion of mounting table and the lifter pin for submerging and watching as the drive division for rising or falling the lifter pin The exception of the lifter pin is detected in the substrate board treatment for taking motor, and the feature of the method for detecting abnormality of the lifter pin exists In, including：

The up step for making the lifter pin increase from the first height and position；

Detecting step, according to the output valve of the motor driver from the servomotor, before detecting the lifter pin Hold the abutting with the lower surface of the mounting thing for being placed in the substrate supporting face；With

Anomalies detecting step, based on front end and the following table for loading thing from first height and position to the lifter pin Amount of movement till the height and position that face abuts or the shifting to the second height and position for stopping the lifter pin after abutting Momentum, detects the exception of the lifter pin.

The method for detecting abnormality of 18. lifter pins as claimed in claim 17, it is characterised in that：

To carry out as the command pulse of the servomotor and the delay pulse of the difference of feedback pulse as the output valve Monitor.

The method for detecting abnormality of 19. lifter pins as claimed in claim 17, it is characterised in that：

The torque value of the servomotor is monitored as the output valve.

The method for detecting abnormality of 20. lifter pins as claimed in claim 17, it is characterised in that：

The servomotor is arranged to switch following speed：

The first actuating speed of the lifter pin is driven in order to carry out the handing-over of the substrate；With

In order to detect the front end of the lifter pin with described mounting thing lower surface abutting and drive the lifter pin, compare institute The second little actuating speed of the first actuating speed is stated,

The up step is carried out with second actuating speed.