JPH0676193A - Method and device for measuring information in vacuum chamber - Google Patents

Abstract

PURPOSE:To measure information in a vacuum chamber simply and in time series and to transmit it to the outside of the vacuum chamber by transmitting data measured by a sensor in the vacuum chamber by radio. CONSTITUTION:A substrate 5 to be processed in the vacuum chamber 4 is set on a substrate holder 6 to be processed, and the sensor 3 which measures temperature, processing speed (film thickness, etc.), pressure, and a plasma parameter (floating potential), etc., that are the information is mounted on the substrate 5 to be processed. The information detected by the sensor 3 is converted to radio information by a transmitter connected to the sensor 3 by an electric cable 8 and a sensor information processor 1, and is sent to the outside of the vacuum chamber 4. A receiver and a sensor information processor 2 installed outside the vacuum chamber 4 receive the radio information sent from the transmitter and the sensor information processor 1, and the information detected by the sensor 3 can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides information on the inside of a vacuum chamber in a vacuum apparatus used for semiconductors, liquid crystal panels, etc., particularly information on a substrate to be processed such as a semiconductor wafer or a glass substrate to be processed in the vacuum chamber. TECHNICAL FIELD The present invention relates to a method for measuring and transmitting and a device therefor.

[0002]

2. Description of the Related Art Pressure, temperature, gas species, plasma parameters (floating potential), processing speed (film thickness), etc. can be considered as information inside a vacuum chamber.
Conventionally, in order to measure such information, it is general to use a fixed sensor and take out the information to the outside of the vacuum chamber with an electric cable connected to it. At this time, a vacuum seal is required by some method.

FIG. 14 shows an example of a conventional information measuring device in a vacuum chamber.

A substrate 5 to be processed in the vacuum chamber 4 is set on a substrate holder 6 to be processed, and the substrate 5 to be processed has temperature, film thickness, pressure, flow, which is information on the surface of the substrate to be processed.
A sensor 3 for measuring a toning potential or the like is attached. The information detected by the sensor 3 is transmitted to the sensor signal processing device 7 outside the vacuum chamber 4 through the electric cable 8 connected to the sensor 3 to obtain the measurement result.

Further, the sensor 3 is not limited to measuring information on the substrate 5 to be processed, but is arranged at various places in the vacuum chamber 4 to measure information.

[0006]

However, in the above-mentioned prior art, the information of the surface of the substrate to be processed, that is, the temperature, which is most desired to know,
When measuring film thickness, floating potential, etc.,
Particularly, in a vacuum device having a structure in which a substrate to be processed moves according to a processing process, there is a problem that it is difficult to route an internal electric cable.

Further, in a vacuum apparatus having a multi-chamber structure, each vacuum chamber is closed by a vacuum valve, so that it is practically impossible to perform measurement.

Therefore, the present invention solves such a problem, and the purpose thereof is to simplify the information in the vacuum chamber, particularly the information on the surface of the substrate to be processed, regardless of the structure of the vacuum apparatus. In addition, there is provided a method and an apparatus for measuring and transmitting time-sequentially to the outside of the vacuum chamber.

[0009]

A method for measuring information in a vacuum chamber according to the present invention is a method for measuring and transmitting information in the vacuum chamber, wherein a sensor for measuring information is arranged in the vacuum chamber. The basic characteristic is that the information measured by the sensor is wirelessly transmitted to the outside of the vacuum chamber, and the information provided in the vacuum chamber is transmitted to the outside of the vacuum chamber by being received by a receiver provided outside the vacuum chamber. To do.

Further, it is desirable to provide a plurality of the sensors for measuring information in the vacuum chamber, and to dispose the plurality of sensors at a plurality of places in the vacuum chamber,
In that case, a plurality of wireless carrier frequencies transmitted from inside the vacuum chamber and received outside the vacuum chamber are used, and a plurality of pieces of information measured by the plurality of sensors are assigned to the respective carrier frequencies to be transmitted and received. It is desirable to transmit information by doing so, or to transmit information by sequentially transmitting and receiving a plurality of information obtained from the plurality of sensors one by one in a time division manner.

Further, the information measured by the sensor is expressed by a time interval of a pulse train, and the pulse train generates a pulse burst wave of a wireless carrier frequency to be transmitted from inside the vacuum chamber and received outside the vacuum chamber to display the information. Transmitting, or expressing the information measured by the sensor in a digital code string, by the digital code string to generate a pulse burst wave of a wireless carrier frequency to be transmitted from inside the vacuum chamber and received outside the vacuum chamber It is desirable to convey information.

The information measuring device in the vacuum chamber of the present invention is a device for measuring and transmitting information in the vacuum chamber, and a sensor for measuring information in the vacuum chamber and a sensor for measuring the information. A modulation circuit for converting information into a signal for wireless transmission, a transmission circuit for wirelessly transmitting a signal from the modulation circuit, and a device for receiving information transmitted from the transmission circuit outside the vacuum chamber. It is basically characterized by comprising a receiving circuit and a demodulation circuit for converting a signal from the receiving circuit into information measured by the sensor.

Further, the sensor, which is generated in response to a change in environment in the vacuum chamber or a change in a circuit portion arranged in the vacuum chamber with time, caused by a change in environment in the vacuum chamber or a change in circuit portion arranged in the vacuum chamber with time. It is desirable to include an error detection circuit that detects a measurement error of the measured information of.

Further, it is desirable to add a carrier frequency switching circuit for selectively switching a wireless carrier frequency transmitted from inside the vacuum chamber and received outside the vacuum chamber to the transmission circuit and the reception circuit.

In addition, it is desirable to add a reception monitor circuit for monitoring the quality of the wireless reception state to the circuit portion arranged outside the vacuum chamber.

Further, it is desirable to provide a primary battery or a secondary battery as a power source for the circuit portion arranged in the vacuum chamber. In that case, a power supply voltage is supplied to the power source for the circuit portion arranged in the vacuum chamber. To add a constant voltage circuit to keep constant, or to separate or connect the circuit unit and the power source of the circuit unit arranged in the vacuum chamber, and to connect or disconnect the power source of the circuit unit and the power source of the circuit unit. Is desirable.

Further, in the information measuring device in the vacuum chamber of the present invention, the location of the sensor placed in the vacuum chamber and the location of the circuit part other than the sensor placed in the vacuum chamber are determined separately. It is characterized by doing.

Further, the information measuring device in the vacuum chamber of the present invention is such that the periphery of the circuit section arranged in the vacuum chamber is
The present invention is characterized in that the circuit portion arranged in the vacuum chamber is covered with a material that blocks a gas emitted from the material used for the circuit portion, or the circuit portion arranged in the vacuum chamber is subjected to a treatment for blocking the emitted gas.

Further, in the information measuring device in the vacuum chamber of the present invention, the difference or ratio between the information measured by the sensor and the information measured by the sensor different from the sensor, or the sensor different from the sensor. The information itself to be measured as a correction value is calculated and stored in advance at a plurality of points within the information measurement range measured by the sensor, and the information measured by the sensor in the vacuum chamber is corrected by the correction value. Is characterized by.

Further, the information measuring device in the vacuum chamber of the present invention constitutes a vacuum device having a vacuum chamber in which the sensor measures the information measured by the sensor, or a pre-process process related to the vacuum device. It is characterized by being used as control information of device operating conditions in the device.

[0021]

According to the above configuration of the present invention, the information in the vacuum chamber, particularly the information on the substrate to be processed which is processed while moving, is measured and measured by the sensor arranged on the substrate. Information is continuously transmitted outside the vacuum chamber by cordless wireless means. Since the wireless means is cordless, it does not depend on the movement of the substrate to be processed. In addition, by installing the circuit parts other than the sensor in the vacuum chamber on the substrate holder, it is possible to move outside the environment of heat and plasma on the substrate while moving along with the substrate. .

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an information measuring device in a vacuum chamber according to an embodiment of the present invention.

The target substrate 5 in the vacuum chamber 4 is set on the target substrate holder 6, and the target substrate 5 has temperature, processing speed (film thickness, etc.), pressure, which is information of the target substrate surface. A sensor 3 for measuring plasma parameters (floating potential) and the like is attached. The information detected by the sensor 3 is converted into wireless information by the transmitter and the sensor information processing device 1 connected to the sensor 3 by the electric cable 8 and sent to the outside of the vacuum chamber 4. The receiver / sensor information processing device 2 outside the vacuum chamber 4 receives the wireless information sent from the transmitter / sensor information processing device 1, and obtains the information detected by the sensor 3 from the received wireless information.

If the substrate 5 to be processed is fixed in a fixed position in the vacuum chamber 4 and does not move, the mounting position of the transmitter and the sensor information processing device 1 may be any position in the vacuum chamber 4. However, in an in-line configuration or a multi-chamber configuration in which the substrate 5 to be processed moves in the vacuum chamber 4, or a configuration in which the substrate 5 to be processed is rotationally moved, it is preferable to set it separately from the sensor 3. In this case, the transmitter and the sensor information processing device 1 are attached to the processing substrate 5 such that the transmitter and the sensor information processing device 1 do not interfere with the connection with the sensor 3 that moves along with the processing substrate 5. Mounted directly on the
It may be mounted in a place such as a processed substrate holder 6 that conveys the processed substrate 5 as shown in (4) where the positional relationship with the processed substrate 5 does not change and is maintained within a certain distance range. With this mounting method, the transmitter and the sensor information processing device 1 can transmit the measurement information obtained from the sensor 3 without interruption. Further, when the transmitter and the sensor information processing device 1 are attached to a target substrate holder 6, such as a target substrate holder 6, where the positional relationship with the target substrate 5 does not change, the target substrate 5 is mounted. The effect of reducing the influence of the action (temperature, voltage, plasma, etc.) on the transmitter and the sensor information processing device 1 and the attachment structure of the transmitter and the sensor information processing device 1 which are heavy objects on the substrate 5 to be processed are required. There is convenience not to do.

Further, the sensor 3, the transmitter, and the sensor information processing device 1 may be attached to the side wall of the vacuum chamber 4 or in a vacuum atmosphere to detect information other than the surface information of the substrate 5 to be processed. In this case, as compared with the conventional method shown in FIG. 14 in which a fixed sensor 3 is used and information is taken out of the vacuum chamber 4 by an electric cable 8 connected thereto, a vacuum seal is not required. And that it is easy to change the sensor mounting position,
Further, it is particularly advantageous in that no modification work of the vacuum chamber 4 is required when it is necessary to attach the information measuring device after the completion of the vacuum chamber 4.

FIG. 2 shows an information measuring device in a vacuum chamber for multipoint measurement according to an embodiment of the present invention.

The target substrate 5 in the vacuum chamber 4 is set on the target substrate holder 6, and the target substrate 5 has information on the surface of the target substrate such as temperature, film thickness, pressure and flow.
A plurality of sensors 3 for measuring the toning potential and the like are attached. The information detected by the sensor 3 is converted into wireless information by the transmitter and the sensor information processing device 1 connected to the sensor 3 by the electric cable 8 and sent to the outside of the vacuum chamber 4. The receiver / sensor information processing device 2 outside the vacuum chamber 4 receives the wireless information sent from the transmitter / sensor information processing device 1, and obtains the information detected by the sensor 3 from the received wireless information.

As described above, by installing the sensor 3 attached to the substrate 5 to be processed at a plurality of places on the substrate 5 to be processed, it is possible to grasp the distribution of the amount of measurement information and to measure the measurement time axis. Two-dimensional data can be obtained in combination with.

FIG. 3 is a main block diagram of an information measuring device in a vacuum chamber according to an embodiment of the present invention.

The information obtained from the sensor circuit 11 is converted by the modulation circuit 12 into an electric signal required by the transmission circuit 13. The transmission circuit 13 generates radio information 19 based on the electric signal obtained from the modulation circuit 12, and transmits the radio information from the transmission antenna 14. The receiving circuit 16 converts the wireless information 19 received through the receiving antenna 15 into an electric signal and sends it to the demodulation circuit 17. The demodulation circuit 17 converts the electric signal from the reception circuit 16 into measurement information obtained by the sensor circuit 11 and sends it to the processing / display means 18. The processing / display means 18 corrects / measures the measurement information obtained by the sensor circuit 11.
It takes charge of output or storage of measurement results or control of other circuits by adding necessary information such as conversion.

The sensor used in the sensor circuit 11 is
When measuring temperature, use a thermistor, platinum resistance thermometer,
When measuring the film thickness of a thermocouple, the vibration frequency is stable due to the film thickness generated by the sensor. When measuring pressure, the vibration frequency is stable due to the pressure change. A crystal oscillator for pressure measurement that changes to 1 is used, and a voltage detection element is used when measuring the floating potential.

FIG. 4 is a transmission circuit diagram of an information measuring device for measuring temperature as information in the vacuum chamber according to the present invention.

The NTC thermistor 21 is a temperature sensor having a property that the electric resistance decreases as the temperature rises. The NTC thermistor 21 is used as a resistor, and the capacitor 22 and the inverter 24 form an oscillation circuit 29. The oscillator circuit 29 corresponds to the sensor circuit 11 in FIG. The resistor 23 is a resistor for linearization correction of the NTC thermistor 21. The oscillation frequency of the oscillation circuit 29 is inversely proportional to the product of the combined resistance value of the NTC thermistor 21 and the resistor 23 and the capacitance of the capacitor 22, and when the resistance value of the NTC thermistor 21 decreases as the measurement temperature rises, the oscillation frequency of the oscillation circuit 29. Will be higher.

NTC thermistor 21 which is a temperature sensor
Oscillation circuit 2 that converts the temperature information measured by
An output 101 of 9 is input to a frequency divider (counter) 25 and converted into a carrier signal 102 and a burst generation timing signal 103. Burst generation timing circuit 26
Generates a timing to turn on / off the carrier signal 102 by the burst generation timing signal 103 to generate a burst signal 104. Therefore, the burst generation time interval of the burst signal 104 becomes shorter as the cycle time of the burst generation timing signal 103 decreases, that is, the measured temperature rises. Output 101 of oscillator circuit 29
To the burst signal 104 correspond to the modulation circuit 12 of FIG.

The burst signal 104 is transmitted to the transistor 28.
Is transmitted to the transmitting antenna 27 via the radio wave and is wirelessly transmitted.

The signal wirelessly transmitted at this time is as shown in FIG. The burst wave 68 is formed by the carrier signal repeatedly generated at the cycle Tc, and the burst wave 6
The occurrence time interval Ts of 8 represents information on the measured temperature.

The carrier signal 102 which is a radio frequency is also used.
The frequency can be switched by the carrier frequency switching circuit composed of the switch 30, and when a plurality of this measuring apparatus are used at the same time, different radio frequencies can be used by each measuring apparatus.

FIG. 5A is a transmission circuit diagram 1 of an information measuring device for multipoint measurement for measuring temperature as information in the vacuum chamber according to the present invention.

NTC thermistor 31 which is a temperature sensor
3 are used, each of which is connected to the oscillation circuit 29 shown in FIG.
Is output. The oscillation frequency of the oscillation circuit 29 increases as the temperature of the NTC thermistor 31 rises. The output 111 of the oscillation circuit obtained by converting the temperature information measured by the temperature sensor into the oscillation frequency is input to the selector (selector) 36.

The reference oscillating circuit 38 composed of the resistor 33, the capacitor 32, and the inverter 34 has a role of sequentially selecting the outputs 111 of the three oscillating circuits 29 one by one and wirelessly transmitting the outputs 111. It plays the role of an identification signal of each sensor, and also plays the role of an error detection circuit that detects a measurement error caused by environmental changes in the vacuum chamber or changes over time in the entire transmission circuit section.

The output 112 of the reference oscillation circuit 38 is the frequency divider 3
5 is connected to the input of 5 and outputs 114, 11 of the frequency divider 35.
It is the original number of 5,116. Output 11 of frequency divider 35
4, 115 and 116 are connected to the selection signal input of the selector 36. The selector 36 outputs this output 114, 115, 11
6, the input signals D0 to D3 are sequentially placed on the output 113 of the selector 36. The output 113 of the selector 36 is input to the wireless circuit 37. The wireless circuit 37 turns on / off the transmission of the wireless carrier frequency at the timing of the input signal and wirelessly transmits the input signal.

The output 112 of the reference oscillation circuit 38 is also connected to the input of the selector 36, so that the radio signal transmitted from the radio circuit 37 is as shown in FIG. 8 (a). Signal 6 including burst wave 69 by carrier signal
The signals 61, 62, 63, and 64 are the same as the reference oscillation circuit 38.
And the signals 62, 63, and 64 are output from the oscillation circuit 29, and signals are repeatedly generated in this order. There is no signal between each signal for the same time as the signal oscillation time T, which is advantageous in terms of power consumption as compared with the case where signals are continuously transmitted. The signal 61 output from the reference oscillating circuit 38 is used for recognition of the signals 62, 63, 64, that is, plays the role of an identification signal of each sensor, and the oscillation frequency of the reference oscillating circuit 38 changes with temperature. By setting it outside the range of change of the oscillation frequency of the oscillation circuit 29, it is possible to discriminate from other signals and fulfill the above-mentioned role.

Further, the reference oscillator circuit 38 is an oscillator circuit 29.
With the same circuit configuration as the above, it is possible to detect the deviation of the oscillation frequency caused by the environmental change in the vacuum chamber occurring in the oscillation circuit 29 or the numerical change of the circuit element or the like due to the temporal change of the entire transmission circuit section. Since the oscillating circuit 29 and the reference oscillating circuit 38 have an oscillating circuit configuration having almost the same configuration, the deviation of the oscillating frequency due to the circuit system caused by the change in the surrounding environment or the change over time changes at the same ratio. Therefore, if the change in the oscillation frequency of the reference oscillation circuit 38 is monitored, the error amount of each sensor can be calculated. In FIG. 8A, when the initial frequency of the signal 61 that is the output of the reference oscillation circuit 38 is f1, the measured frequency of the sensor at a certain time point is fs, and the frequency of the signal 61 at that time point is f2, The corrected measurement frequency f of the sensor excluding the error can be calculated by f = fs × (f1 / f2). As described above, the reference oscillation circuit 38 functions as an error detection circuit that detects a measurement error.

FIG. 5 (b) is a transmission circuit diagram 2 of the information measuring device for multipoint measurement for measuring the temperature as the information in the vacuum chamber according to the present invention.

When a plurality of sensors are used, FIG.
As shown in (a), in addition to the method of transmitting and receiving the information obtained from each sensor one by one in a time division manner using only one radio frequency, a plurality of radio frequencies used for transmission and reception are used. There is a way.

The circuit diagram of FIG. 5 (b) corresponds to that, three NTC thermistors 31 which are temperature sensors are used, and the oscillation circuits 29 shown in FIG. 4 are connected to each of them, and the oscillation circuit output from each sensor is output. 111 is output. The output 111 of each oscillation circuit, which is obtained by converting the temperature information measured by the temperature sensor into the oscillation frequency, is input to another radio circuit 37. Each radio circuit 37 performs transmission on / off of different radio carrier frequencies at the timing of the input signal and wirelessly transmits the input signal.

The radio signal is simultaneously transmitted as a signal in which burst waves 65, 66 and 67 having different carrier frequencies are continuously generated as shown in FIG. 8B. The generation interval times T1, T2, and T3 of the burst waves 65, 66, and 67 in the wireless signals A, B, and C represent the temperature information measured by the respective sensors.

FIG. 10 is a transmission circuit diagram of a temperature measuring device for transmitting digital data according to the present invention.

In the configurations of FIGS. 4, 5A, and 5B, the oscillation frequency of the oscillation circuit connected to the sensor, that is, FIG.
The time interval Ts of the continuous pulse generated from the oscillation circuit like the pulse signal of 1 represents the temperature information, and the transmission / reception of the wireless carrier frequency is performed at the time interval Ts of the continuous pulse generation. The burst wave 68 is wirelessly transmitted. On the other hand, there is a method in which the measurement information measured by the sensor is converted into digital data, and the converted digital data codes 1 and 0 are assigned without a burst wave like the digital code in FIG. 9 and wirelessly transmitted.

The circuit diagram of FIG. 10 corresponds to this. An NTC thermistor 71, which is a temperature sensor, and a resistor 72 are connected in series and a constant voltage is applied. NTC thermistor 7
The voltage 121 divided by the resistance ratio of 1 and the resistance 72 changes depending on the temperature detected by the NTC thermistor 71, which is a temperature sensor. The voltage 121 is connected to the serial A / D converter 74 through the buffer amplifier 73, where the temperature information is converted into a serialized digital code string. The output 122 of the A / D converter 74, which is a serialized digital code string, is input to the wireless circuit 75,
Transmission / reception of the wireless carrier frequency is performed at the timing of the input signal, and the input signal is wirelessly transmitted.

FIG. 6 is a film thickness measurement transmission circuit diagram for multipoint measurement according to the present invention.

The crystal oscillator 4 for film thickness measurement in which the vibration frequency is stably changed by the film thickness (film weight) generated in the sensor.
Oscillation circuit 42 including a resistor, a capacitor, and an inverter is connected to each of the three, and each film thickness sensor outputs an oscillation circuit output 131. The oscillation frequency of the oscillator circuit 42 decreases in proportion to the thickness of the film formed on the crystal oscillator 41. The output 131 of the oscillation circuit obtained by converting the film thickness information measured by the film thickness sensor into the oscillation frequency is input to the selector 44 after being frequency-divided via the frequency divider 43.

The reference oscillating circuit 47 composed of a resistor, a capacitor, and an inverter has a role of sequentially selecting one from the outputs 131 of the three oscillating circuits 42 for wireless transmission, and the output of the three oscillating circuits, that is, of each sensor. It plays the role of an identification signal, and also the role of an error detection circuit that detects a measurement error that occurs due to environmental changes in the vacuum chamber or changes over time in the entire transmission circuit section.

The output 132 of the reference oscillation circuit 47 is the frequency divider 4
6 inputs and outputs 134, 13 of divider 46
It is the original vibration of 5,136. Output 13 of frequency divider 46
4, 135 and 136 are connected to the selection signal input of the selector 44. The selector 44 outputs these outputs 134, 135, 13
According to 6, input signals D0 to D3 are sequentially output from the selector 1
I will put it on 33. The output 133 of the selector 44 is input to the wireless circuit 45. The wireless circuit 45 performs transmission ON / OFF of the wireless carrier frequency at the timing of the input signal and wirelessly transmits the input signal.

The output 132 of the reference oscillation circuit 47 is also connected to the input of the selector 44, and as a result, the radio signal transmitted from the radio circuit 45 is as shown in FIG. 8 (a). Signal 6 including burst wave 69 by carrier signal
The signals 61, 62, 63, and 64 are the same as the reference oscillation circuit 47.
From the oscillator circuit 42 via the frequency divider 43, and the signals 62, 63, 64 are repeatedly generated in this order. There is no signal between each signal for the same time as the signal oscillation time T, which is advantageous in terms of power consumption as compared with the case where signals are continuously transmitted. The signal 61 output from the reference oscillation circuit 47 is a signal 62,
It is used for recognition of 63, 64, that is, plays a role of an identification signal of each sensor, and the oscillation frequency of the reference oscillation circuit 47 is set outside the variation range of the oscillation frequency of the oscillation circuit 42 due to temperature change. It can be distinguished from the signal of and can play the above-mentioned role.

Further, the reference oscillation circuit 47 includes an oscillation circuit 42.
By adopting the same kind of circuit configuration as described above, it is possible to detect the deviation of the oscillation frequency caused by the environmental change in the vacuum chamber in the oscillation circuit 42 or the numerical change of the circuit element or the like due to the temporal change of the entire transmission circuit section. Since the oscillating circuit 42 and the reference oscillating circuit 47 have an oscillating circuit configuration having almost the same configuration, the deviation of the oscillating frequency due to the circuit system caused by the change in the surrounding environment or the change over time changes at the same ratio. Therefore, if the change in the oscillation frequency of the reference oscillation circuit 47 is monitored, the error component of each sensor can be calculated. In FIG. 8A, the initial frequency of the signal 61 which is the output of the reference oscillation circuit 47 is f1, the measured frequency of a sensor at a certain time point is fs, and the signal 61 at that time point is
If the frequency is f2, the corrected measurement frequency f of the sensor excluding the error can be calculated by f = fs × (f1 / f2). As described above, the reference oscillation circuit 47 serves as an error detection circuit that detects a measurement error.

FIG. 7 is a receiving circuit diagram according to the present invention.

The information measured by the sensor is converted into a burst wave generation time interval by a carrier signal, and the signal transmitted wirelessly is caught by the receiving antenna 51, and RF is transmitted.
After being amplified by the amplifier 52, it is input to the demodulation circuit 53. The demodulation circuit 53 tunes to a radio carrier frequency to discriminate a signal of a designated frequency, then eliminates the carrier signal through a low-pass filter, and outputs only a pulse signal which is information measured by the sensor. That is, a pulse signal is generated from the radio signal in FIG. The output 141 of the demodulation circuit 53 converted into the pulse signal which is the information measured by the sensor is input to the counter 55. Counter 55
Then, the pulse time interval of the output 141 of the demodulation circuit 53 is measured by the time unit of the reference oscillator 56. Counter 55
The result 142 counted by is read into a microcomputer or the like and finally converted into the true information measured by the sensor, and the sensor measurement value can be obtained.

In the demodulation circuit 53, if the carrier frequency switching circuit is provided on the transmitter side and the carrier frequency can be switched, the frequency tuned to the carrier frequency is changed according to the carrier frequency set on the transmitter side.

Further, as shown in FIG. 5B, when a plurality of radio frequencies used for a plurality of transmissions / receptions are used, the configuration shown in FIG. 7 may be adopted as many as the number of radio frequencies used.

Further, when the information measured by the sensor as shown in FIG. 10 is converted into digital data and serially transmitted, a serial data conversion circuit for recognizing the serial data may be formed instead of the counter 55. .

The comparator 54 outputs the output 1 of the demodulation circuit 53.
It is a monitor circuit that inputs 41 and monitors the quality of the wireless reception state. Output 1 if there is no problem in the reception status
LED57 blinks regularly at 41 pulse generation intervals,
When the reception state is bad or no reception is being made, the LED 57 keeps on or off, or blinks irregularly.

In this embodiment, as the modulation mode of wireless transmission, the information measured by the sensor is converted into the burst wave generation time interval by the carrier signal and wirelessly transmitted, but instead of pulse modulation. Even if a frequency modulation (FM modulation) system or an amplitude modulation (AM modulation) system is adopted for the above, it does not fall within the scope intended by the present applicant. From the material used for the transmission circuit section arranged in the vacuum chamber, if no measures are taken as it is, an outgassing gas which is inconvenient for processing the substrate to be processed is generated. Therefore, the periphery of the transmission circuit portion arranged in the vacuum chamber is covered with a material that blocks the emitted gas, or the transmission circuit portion is treated to block the emitted gas.

The transmitter arranged in the vacuum chamber is
As shown in FIG. 12B, one or more sensors 83 are composed of a circuit section 81 and a battery section 82 connected by an electric cable 85. In FIG. 12B, the circuit section 81
The battery unit 82 is solidified with a sealing material or an adhesive agent that blocks the released gas, and does not pollute the inside of the vacuum chamber. The sensor 83 and the electric cable 85 are covered with a tube that does not release the released gas.

As a power source for the circuit section arranged in the vacuum chamber, a primary battery, a secondary battery, or both of them are used together.

FIGS. 12 (a) and 12 (b) are circuit diagrams and battery configuration diagrams 1 and 2 in the vacuum chamber according to the present invention.

The transmitter arranged in the vacuum chamber is
One or a plurality of sensors 83 are connected to each other by an electric cable 85, and are composed of a circuit portion 81 and a battery portion 82. The circuit section 81 and the battery section 82 serve as power terminals
Connected at 4.

When the transmitting device is not used, FIG.
As shown in (a), the circuit section 81 and the battery section 82 are separated, and the circuit section 81 is not supplied with power. When the transmitter is used, the circuit unit 81 and the battery unit 82 are connected by the connector 84 as shown in FIG. 12B, power is supplied to the circuit simultaneously with the connection, and the operation as the transmitter is started.

With this structure, parts such as a power switch are not necessary, and the portion not covered with the material used for blocking the emission gas emitted from the transmitter is minimized to a necessary minimum such as a part of the connector 84. You can hold it down.

FIG. 12 (c) is a circuit diagram of the circuit section and battery connection in the vacuum chamber according to the present invention.

The circuit section 81 to which one or more sensors 83 are connected by the electric cable 85 and the battery section 82 are connected by the connector 84 which is a power supply terminal. The battery unit 82 includes a battery 86, a three-terminal regulator 87 that makes the battery voltage output a constant voltage, and a smoothing capacitor 88.

The output voltage of the battery decreases with the consumption of the battery and affects the performance of the transmitter. Therefore, the power supply voltage supplied to the circuit unit 81 is stabilized by using a constant voltage circuit composed of the three-terminal regulator 87 and the smoothing capacitor 88. Further, by inserting the constant voltage circuit, the power supply voltage supplied to the circuit unit 81 becomes lower than the initial battery voltage, so that low power consumption can be realized and the battery life is extended.

Of course, the constant voltage circuit may be provided on the circuit section 81 side.

In order to improve the measurement accuracy of the information measuring device of the present invention, the correction value is actually measured before actually using the information measuring device in the vacuum chamber. The correction value is
It is used to match the information measured by the sensor of this measuring device with the true amount of information being measured, and adds or multiplies the correction value to the information measured by the sensor of this measuring device. It is to get the true amount of information. In other words, the information measured by the sensor of this measurement device and the information measured by the sensor other than the sensor of this measurement device, the difference or ratio of the measurement information of both sensors, or measured by the sensor different from this measurement device. The information itself is used as a correction value and is calculated and stored in advance while controlling the amount of measurement information so that it can be collected at multiple points within the sensor measurement range of the measurement device. The information measured by is corrected by the correction value.

For example, consider the temperature as the information to be measured. Put a sensor of this measuring device and a temperature sensor other than the sensor of this measuring device in a thermostatic chamber that can change the temperature, and change the temperature within the measurable range of the sensor of this measuring device, and measure both sensors. Get the value over multiple points.
The difference or ratio between the obtained temperature measurement values from both sensors is calculated, and the calculated result is stored as a correction value.
If the measured value obtained from the sensor of the present measuring device at a certain temperature T is T1 and the measured value obtained from another temperature sensor is T2, the correction value C is obtained in the form of C = T2-T1. At this time, the temperature measurement value that can be obtained by another temperature sensor must be sufficiently higher in accuracy than the temperature measurement value that can be obtained by the sensor of the present measurement device, and T2 = It is assumed that T 1 is almost satisfied. A plurality of these correction values are collected and stored while changing the temperature. FIG. 11 is a measurement information correction graph according to the present invention, which is a graph of the above-described correction values obtained by collecting a plurality of points. The correction value on the vertical axis is associated with the measurement value measured by the sensor of the measuring device on the horizontal axis.

When the measurement device is actually used in the vacuum chamber, the measurement value measured by the sensor of the measurement device is corrected according to the correction value shown in FIG. Assuming that the temperature measured by the sensor of the present measurement device is Ta in FIG. 11, the temperature measurement result T is obtained by adding the correction value Ca to T = Ta + Ca.

In addition to the method of storing the difference from the true value as the correction value as described above, a method of storing and using the ratio to the true value and the method of measuring the value measured by the sensor of the measuring device and the true value are used. It is also possible to store both of the values and refer to the true value with respect to the measured value measured by the sensor of the measuring device.

FIG. 13 is a vacuum process control chart according to the present invention.

As an information measuring device in the vacuum chamber of the present invention, a transmitter 95 is provided in the vacuum chamber of the vacuum device 91.
However, the receiving unit 94 is installed outside the vacuum device 91. In the front and rear steps of the vacuum device 91, devices including vacuum device 91, devices for forming a vacuum device for processing a substrate to be processed or devices or processes 92 and 93 constituting other processes are arranged. The substrate to be processed is sequentially processed along the process flow 96 in the drawing. Vacuum device 91 obtained by receiving unit 94
The information in the vacuum chamber is transmitted to the vacuum device 91, the devices or steps 92 and 93 that constitute the vacuum device or other processes along the information flow 97, and the processing conditions of the substrate to be processed are indicated in each device or step. Used as control information to change.

The information in the vacuum chamber of the vacuum apparatus 91 obtained by the receiving unit 94 is related to all the apparatus related to the target substrate to be processed by the vacuum apparatus 91 irrespective of only the immediately preceding and succeeding steps of the vacuum apparatus 91. , Can be used in the process.

[0082]

As described above, according to the present invention, a sensor for measuring information is arranged in the vacuum chamber,
The data measured by this sensor is wirelessly transmitted to the outside of the vacuum chamber, and the receiver installed outside the vacuum chamber transmits the data to the outside of the vacuum chamber, so that the vacuum device of any configuration can generate a vacuum. It has an effect that information in the chamber, particularly information on the surface of the substrate to be processed can be easily and time-sequentially measured and transmitted to the outside of the vacuum chamber. Further, when the apparatus of the present invention is installed in the vacuum chamber, there is an effect that it can be installed without any work or modification that breaks the vacuum tightness.

[Brief description of drawings]

FIG. 1 is a diagram of an information measuring device in a vacuum chamber according to an embodiment of the present invention.

FIG. 2 is a diagram of an information measuring device in a vacuum chamber for multipoint measurement according to an embodiment of the present invention.

FIG. 3 is a main configuration diagram of an information measuring device in a vacuum chamber according to an embodiment of the present invention.

FIG. 4 is a temperature measurement transmission circuit diagram according to the present invention.

FIG. 5 (a) is a temperature measurement transmission circuit diagram 1 for multipoint measurement according to the present invention. (B) Temperature measurement transmission circuit for multipoint measurement according to the present invention FIG. 2
Is.

FIG. 6 is a film thickness measurement transmission circuit diagram for multipoint measurement according to the present invention.

FIG. 7 is a receiving circuit diagram according to the present invention.

FIG. 8A is a radio signal diagram using multiple waves according to the present invention. (B) is a radio signal diagram for single wave use according to the present invention.

FIG. 9 is a converted signal diagram of information according to the present invention.

FIG. 10 is a transmission circuit diagram of a temperature measurement transmission device for transmitting digital data according to the present invention.

FIG. 11 is a measurement information correction graph according to the present invention.

FIG. 12 (a) is a circuit configuration diagram and a battery configuration diagram 1 in a vacuum chamber according to the present invention. (B) FIG. 2 is a circuit configuration diagram and a battery configuration diagram in the vacuum chamber according to the present invention. (C) It is a circuit diagram and a battery connection circuit diagram in the vacuum chamber according to the present invention.

FIG. 13 is a vacuum process control chart according to the present invention.

FIG. 14 is a diagram of a conventional information measuring device in a vacuum chamber.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transmitter and sensor information processing device 2 ... Receiver and sensor information processing device 3 ... Sensor 4 ... Vacuum chamber 5 ... Processed substrate 6 ... Processed substrate holder 7 ... ..Sensor signal processing device 8,85 ... Electrical cable 11 ... Sensor circuit 12 ... Modulation circuit 13 ... Transmission circuit 14,27 ... Transmission antenna 15, 51 ... Reception antenna 16. ..Reception circuit 17, 53 ... Demodulation circuit 18 ... Processing / display means 19 ... Radio information 21, 31, 71 ... NTC thermistor 22, 32 ... Capacitor 23, 33, 72 ... -Resistance 24, 34 ... Inverter 25, 35, 43, 46 ... Divider 26 ... Burst generation timing circuit 28 ... Transistor 29, 42 ... Oscillation circuit 30 ...・ Switches 36, 44 ... Selectors 37, 45, 75 ... Wireless circuits 38, 47 ... Reference oscillation circuit 41 ... Film thickness measuring crystal oscillator 52 ... RF amplifier 54 ... Comparator 55 ... Counter 56 ... Reference oscillator 57 ... LED 61 ... Output from reference oscillation circuit 62, 63, 64 ... Output from frequency divider 65, 66, 67, 68, 69 ... Burst wave 73 ... Buffer amplifier 74 ... Serial A / D converter 81 ... Circuit part 82 ... Battery part 83 ... Sensor 84 ... Connector 86 ... Battery 87 ...・ Three-terminal regulator 88 ・ ・ ・ Smoothing capacitor 91 ・ ・ ・ Vacuum device 92, 93 ・ ・ ・ Vacuum device or other device or process constituting the process 94 ・ ・ ・ Reception unit 95 ・ ・ ・ Transmission unit 9・ ・ ・ Process flow 97 ・ ・ ・ Information flow 101, 111, 131 ・ ・ ・ Oscillation circuit output 102 ・ ・ ・ Carrier signal 103 ・ ・ ・ Burst generation timing signal 104 ・ ・ ・ Burst signal 112,132 Output of reference oscillation circuit 113, 133 ... Output of selector 114, 115, 116, 134, 135, 136 ...
Output of frequency divider 121 ... Divided voltage 122 ... Output of A / D converter 141 ... Output of demodulation circuit 142 ... Result counted by counter

Claims (17)

[Claims] 1. A method for measuring and transmitting information in a vacuum chamber, wherein a sensor for measuring information is arranged in the vacuum chamber, and the information measured by the sensor is wirelessly transmitted to the outside of the vacuum chamber. Then, the information measuring method in the vacuum chamber is characterized in that the information in the vacuum chamber is transmitted to the outside of the vacuum chamber by receiving the information in a receiver provided outside the vacuum chamber. 2. A device for measuring and transmitting information in a vacuum chamber, comprising: a sensor for measuring information in the vacuum chamber; and a signal for wirelessly transmitting the information measured by the sensor. A modulation circuit for conversion,
A transmission circuit for wirelessly transmitting a signal from the modulation circuit,
Further, a vacuum characterized by comprising a reception circuit for receiving information transmitted from the transmission circuit and a demodulation circuit for converting a signal from the reception circuit into information measured by the sensor, outside the vacuum chamber. Information measuring device in the chamber. 3. The vacuum chamber according to claim 1, wherein a plurality of the sensors for measuring information in the vacuum chamber are provided, and the plurality of sensors are arranged at a plurality of places in the vacuum chamber. Information measurement method. 4. A plurality of pieces of information measured by the plurality of sensors using a plurality of wireless carrier frequencies transmitted from inside the vacuum chamber and received outside the vacuum chamber,
The information measuring method in the vacuum chamber according to claim 3, wherein the information is transmitted by allocating and transmitting to each of the carrier frequencies. 5. The information measurement in the vacuum chamber according to claim 3, wherein a plurality of pieces of information obtained from the plurality of sensors are sequentially transmitted and received one by one in a time division manner. Method. 6. The information measured by the sensor is expressed by a time interval of a pulse train, and the pulse train generates a pulse burst wave of a wireless carrier frequency to be transmitted from inside the vacuum chamber and received outside the vacuum chamber to display the information. The method for measuring information in a vacuum chamber according to claim 1, wherein the information is transmitted. 7. The information measured by the sensor is represented by a digital code string, and the digital code string generates information by generating a pulse burst wave of a wireless carrier frequency to be transmitted from inside the vacuum chamber and received outside the vacuum chamber. The method for measuring information in a vacuum chamber according to claim 1, wherein the information is transmitted. 8. In response to a change in environment in the vacuum chamber or a change over time in a circuit portion arranged in the vacuum chamber,
3. The error detection circuit according to claim 2, further comprising an error detection circuit for detecting a measurement error of information measured by the sensor caused by a change in environment in the vacuum chamber or a change with time in a circuit unit arranged in the vacuum chamber. Information measuring device in the vacuum chamber. 9. A carrier frequency switching circuit for selectively switching a wireless carrier frequency transmitted from inside the vacuum chamber and received outside the vacuum chamber is added to the transmission circuit and the reception circuit. Two
The information measuring device in the vacuum chamber according to. 10. The information measuring device in the vacuum chamber according to claim 2, wherein a reception monitor circuit for monitoring the quality of the wireless reception state is added to a circuit portion arranged outside the vacuum chamber. 11. The information measuring device in the vacuum chamber according to claim 2, wherein a primary battery or a secondary battery is provided as a power source of a circuit unit arranged in the vacuum chamber. 12. The information measuring device in the vacuum chamber according to claim 11, wherein a constant voltage circuit for maintaining a constant power supply voltage is added to the power source of the circuit section arranged in the vacuum chamber. 13. The circuit unit arranged in the vacuum chamber and the power supply for the circuit unit are separate bodies, and the circuit unit and the power supply for the circuit unit are connected or separated. The information measuring device in the vacuum chamber according to. 14. The arrangement place of the sensor arranged in the vacuum chamber and the arrangement place of the circuit part other than the sensor arranged in the vacuum chamber are separately determined and arranged. Information measuring device in the vacuum chamber. 15. A circuit part arranged in the vacuum chamber is covered with a material that blocks outgas emitted from a material used for the circuit part arranged in the vacuum chamber, or in a circuit part arranged in the vacuum chamber, The information measuring device in the vacuum chamber according to claim 2, wherein a process of blocking the released gas is performed. 16. Information measured by the sensor,
The difference or ratio with the information measured by the sensor different from the sensor, or the information itself measured by the sensor different from the sensor is used as a correction value, and is calculated in advance at a plurality of points within the information measurement range measured by the sensor. The information measuring device in the vacuum chamber according to claim 2, wherein the information measured by the sensor in the vacuum chamber is corrected by the correction value. 17. The information measured by the sensor,
3. The inside of the vacuum chamber according to claim 2, wherein the sensor is used as control information of a device operating condition in a vacuum device having a vacuum chamber as a measurement target or a device constituting a front-back process related to the vacuum device. Information measuring device.