JP2005194575A - Thin film deposition apparatus, method for controlling exhaust means of the thin film deposition apparatus, and method for producing substrate with thin film deposited thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film deposition apparatus which is unnecessary for any sophisticated flow rate control, simple in structure, compact, inexpensive and easy in maintenance, a method for controlling an exhaust means of the thin film deposition apparatus, and a method for producing a substrate with a thin film deposited thereon. <P>SOLUTION: In the thin film deposition apparatus, high frequency electric field is generated between electrodes facing each other under the atmospheric pressure or the pressure in a vicinity of the atmospheric pressure to form a discharge space, a film-deposition gas and discharge gas to be fed in the discharge space is plasmatized, a thin film is deposited on a substrate by exposing the substrate to the plasmatized gas. The thin film deposition apparatus has an exhaust means to exhaust waste gas containing particles generated in a film deposition chamber. The exhaust means measures the state of floating particles and dust such as particles in the film deposition chamber, and controls the exhaust of a discharge means according to the result of measurement. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus that generates plasma in an atmospheric pressure environment to form a thin film, a method for controlling an exhaust means of the thin film forming apparatus, and a method for producing a substrate on which a thin film is formed. The present invention relates to a method for controlling exhaust means and a method for producing a substrate on which a thin film is formed.

  Conventionally, various materials such as LSIs, semiconductors, display devices, magnetic recording devices, photoelectric conversion devices, Josephson devices, solar cells, photothermal conversion devices, etc. have used many materials with a high-functional thin film on a substrate. It has been.

  These highly functional thin films include, for example, electrode films, dielectric protective films, semiconductor films, transparent conductive films, electrochromic films, fluorescent films, superconducting films, dielectric films, solar cell films, antireflection films, anti-reflection films, Abrasion film, optical interference film, reflection film, antistatic film, conductive film, antifouling film, hard coat film, undercoat film, barrier film, electromagnetic wave shielding film, infrared shielding film, ultraviolet absorption film, lubricating film, shape memory A film, a magnetic recording film, a light emitting element film, a biocompatible film, a corrosion-resistant film, a catalyst film, a gas sensor film, a decorative film, and the like.

  Conventionally, such a high-functional thin film is formed by a wet film formation method represented by a coating method, or a dry film formation method using a vacuum such as a sputtering method, a vacuum evaporation method, or an ion plating method. Has been.

  In recent years, for example, the atmospheric pressure plasma discharge treatment thin film formation method can provide a higher performance thin film than the above-described wet film formation method, and the productivity is higher than the dry film formation method using a vacuum. Etc. are being devised and put into practical use. The greatest merit of the atmospheric pressure plasma discharge processing method is that continuous film formation is possible because it is not necessary to use a vacuum.

  When forming a highly functional thin film, it is of course desirable that the film thickness be uniform over the entire surface of the substrate. In particular, an optical thin film such as an antireflective film is required to have a higher level of film thickness uniformity because the film thickness accuracy directly becomes the film performance.

  In addition, since an optical thin film such as an antireflection film is an extremely thin film, even if a foreign object having a diameter of, for example, about 1 μm, which is smaller than the conventional one, adheres to the substrate or the thin film, a quality abnormality such as a point failure occurs. I understand that.

  The film formation method by atmospheric pressure plasma discharge has a characteristic that particles are likely to be generated by activated unreacted film-forming gas etc. in a portion where the oxygen concentration in the vicinity of the discharge space is high. It has become necessary to remove particles at the time of manufacturing such as.

In film formation using atmospheric pressure plasma discharge, the gas supply amount in the discharge space is made constant by adjusting the flow rate of inflow and outflow of mixed gas. There is known a method (for example, Patent Document 1) for removing foreign substances on a material by adhering them.
JP 2001-98093 A (paragraph numbers 0061 to 0064 FIG. 1)

However, this method of adjusting each flow rate of inflow and outflow requires highly accurate flow rate control on both the gas supply and exhaust sides.
Furthermore, the method of removing foreign matter with the adhesive roller is, for example, the disadvantage that if the adhesive roller is disposed on the base material portion, the foreign matter attached to the film forming portion cannot be removed, such as being restricted by the location of the adhesive roller. Depending on the selection of adhesive strength, the base material and film may be damaged, or the foreign material may not be removed. In addition, the foreign material attached to the adhesive roller will reattach to the base material or film forming part. There is a drawback that there is a possibility.

  As described above, the control method is complicated, the equipment structure is complicated, the size is large, and the cost is high, and it is difficult to manage and maintain the adhesive roller to keep the adhesive force constant.

  In view of the above-mentioned problems, the present invention does not require advanced flow rate control as much as the method for adjusting each flow rate of inflow / outflow described in the background art, has a simple structure of the exhaust means, and is small, inexpensive, and maintenance. It is an object of the present invention to provide an easy-to-use thin film forming apparatus, a method for controlling an exhaust means of the thin film forming apparatus, and a method for producing a substrate on which a thin film is formed.

  Particles mainly refer to fine particles that are generated along with the formation of thin films by plasma, and if they adhere, the quality of the thin film is impaired. For example, a gas mixture that is still active in the vicinity of the discharge space is generated as particles. To do.

  The substrate refers to a base material on which a thin film such as the above-described electrode film or dielectric protective film is formed.

  The above object is achieved by the following components.

1) A discharge space is formed by generating a high-frequency electric field between opposing electrodes under atmospheric pressure or a pressure near atmospheric pressure, and a mixed gas of a film forming gas and a discharge gas supplied to the discharge space A film forming chamber for forming a thin film on the substrate by exposing the mixed gas that has been converted to plasma to a substrate, a mixed gas supply means for supplying the mixed gas into the film forming chamber, and a film forming chamber In a thin film forming apparatus having exhaust means for exhausting waste gas containing generated particles and the like,
A thin film forming apparatus comprising: exhaust means for measuring a state of suspended particles such as particles in the film forming chamber and dust and controlling an exhaust amount of the exhaust means according to the measurement result.

  2) The state of suspended particles such as particles and dust is measured by measuring the number of suspended particles such as particles and dust.

3) The exhaust means includes at least one exhaust port for exhausting the waste gas inside the film forming chamber;
The thin film forming apparatus according to 1) or 2), further comprising a single exhaust member that is connected to the exhaust port via an exhaust path and whose exhaust amount is controlled by a control unit.

4) The exhaust means includes at least one exhaust port for exhausting the waste gas inside the film forming chamber;
At least one exhaust amount adjusting means connected to the exhaust port via an exhaust path, the exhaust amount being controlled by the control means;
The thin film forming apparatus according to 1) or 2), further comprising a single exhaust member connected to the exhaust amount adjusting means via an exhaust path.

5) The exhaust means includes a plurality of exhaust ports for exhausting the waste gas inside the film forming chamber;
The thin film forming apparatus according to 1) or 2), further comprising a plurality of low exhaust amount exhaust members that are connected to the exhaust port via an exhaust path and whose exhaust amount is controlled by a control unit.

  6) The measurement means includes detection means for detecting suspended particles such as particles and dust, and a counter for counting the number of detected suspended particles such as particles and dust. 1) to 5) The thin film forming apparatus according to any one of the above.

  7) The detection means is detection means for detecting floating particles and dust such as particles in the waste gas sampled by sampling means for sampling the waste gas at least in the vicinity of the discharge space. The thin film forming apparatus according to item 6).

8) The high frequency electric field generated between the opposing electrodes is a superposition of the first high frequency electric field and the second high frequency electric field,
The frequency ω2 of the second high frequency electric field is higher than the frequency ω1 of the first high frequency electric field,
The relationship between the first high-frequency electric field strength E1, the second high-frequency electric field strength E2, and the discharge starting electric field strength IE is:
E1 ≧ IE> E2
Or E1> IE ≧ E2
The thin film forming apparatus according to item 7), wherein the output density of the second high-frequency electric field is 1 W / cm ² or more.

9) A discharge space is formed by generating a high-frequency electric field between opposing electrodes under atmospheric pressure or a pressure near atmospheric pressure, and a mixed gas of a film forming gas and a discharge gas supplied to the discharge space A film-forming chamber for forming a thin film on the substrate by exposing the mixed gas that has been converted to plasma to a substrate, a mixed gas supply means for supplying the mixed gas into the film-forming chamber, In the control method of the exhaust means of the thin film forming apparatus having the exhaust means for exhausting the waste gas,
Measuring the quantity of the state of particles generated in the film forming chamber;
Determining an exhaust amount corresponding to the measured value from information of each exhaust amount of the exhaust means for each measured value of the quantity of particle states stored in advance;
And a step of driving the exhaust unit based on the determined exhaust amount to exhaust the waste gas containing particles.

  10) A plurality of thin film forming apparatuses described in 6) are provided in a clean room, and a plurality of the thin film forming apparatuses described in 6) are discharged while exhausting waste gas containing particles according to the state of particles generated in the thin film forming apparatus. A method for producing a substrate in which a thin film having a predetermined thickness is formed on a base material by continuously conveying a web-shaped base material to a thin film forming apparatus.

According to the present invention, the following effects can be obtained. That is,
In a thin film forming apparatus that forms a thin film with plasma generated in an atmospheric pressure environment, the number of particles in the film forming chamber forming the thin film is measured, and the amount of gas exhausted from the film forming chamber is measured based on the measured value. By controlling the flow rate of the thin film forming apparatus and the thin film forming apparatus, which does not require high-accuracy flow rate control, has a simple structure, is small, inexpensive, easy to maintain, and does not adhere to minute foreign matters such as particles. A method for controlling the exhaust means and a method for producing a substrate on which a thin film is formed can be provided.

  The present invention will be described below with reference to the drawings, but the present invention is not limited thereto, and the description in this section is not intended to limit the technical scope of the claims or the meaning of terms.

  Hereinafter, the thin film forming apparatus (atmospheric pressure plasma discharge processing apparatus) of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view showing an example of a thin film forming apparatus of the present invention.

  In the apparatus of FIG. 1, a discharge space is formed by a roll electrode and a plurality of rectangular tube-shaped rod-like electrodes, and a high frequency power source having a frequency of at least 0.5 KHz is connected to each electrode to connect both electrodes. In this configuration, two types of high frequency voltages are applied to the electrode, and an electric field is generated by superimposing the two types of high frequency voltages between the two electrodes.

  By superimposing the high-frequency electric field in this way, even when a discharge gas such as nitrogen having a high discharge start electric field strength is used, a stable and uniform discharge can be obtained.

  100 is a thin film forming apparatus, 140 is a high-frequency electric field generating means having two high-frequency power supplies, 150 is a gas supply means, and 160 is an electrode temperature adjusting means.

  Reference numeral 135 denotes a roll electrode, and a discharge space 132 is formed between a plurality of rectangular tube electrodes 136 disposed to face the roll electrode 135.

  The roll electrode 135 is supplied with a first high-frequency voltage of the voltage V1 from the first power supply 141, and the plurality of rectangular tube electrodes 136 are supplied with a frequency ω2 higher than the frequency ω1 from the second power supply 142. A second high frequency voltage of voltage V2 is applied.

  As a result, an electric field is generated in each electrode, and when the superimposed high-frequency electric field is both a sine wave, the frequency ω1 of the first high-frequency electric field and the frequency ω2 of the second high-frequency electric field higher than the frequency ω1 are superimposed. The waveform becomes a sawtooth waveform in which a sine wave with a higher frequency ω2 is superimposed on a sine wave with a frequency ω1.

  Here, the strength of the electric field at which discharge starts is the minimum electric field intensity that can cause discharge in the discharge space (electrode configuration, etc.) and reaction conditions (gas conditions, etc.) used in the actual thin film formation method. . The discharge start electric field strength varies somewhat depending on the type of gas supplied to the discharge space, the dielectric type of the electrode, or the distance between the electrodes, but is controlled by the discharge start electric field strength of the discharge gas in the same discharge space.

  By applying a high-frequency electric field as described above to the discharge space, it is presumed that a discharge capable of forming a thin film is caused and high-density plasma necessary for forming a high-quality thin film can be generated.

The relationship between the strength E1 of the high-frequency electric field generated by the first power source, the strength E2 of the high-frequency electric field generated by the second power source, and the strength IE of the discharge start electric field.
E1 ≧ IE> E2
Or E1> IE ≧ E2
The power density of the high frequency electric field of the second electrode, 1W / cm ² or more 50 W / cm ² or less (preferably 1.2 W / cm ² or more 20W / cm ² or less) has a,
The output density of the high frequency electric field of the first electrode is 1 W / cm ² or more (preferably 5 W / cm ² or more) and 50 W / cm ² or less.

  The frequency is set so that ω1 is 200 KHz or less, ω2 is 800 KHz or more, or the ratio of ω2 to ω1 is 100 times or more.

  A first filter 143 is installed between the first power supply 141 and the roll electrode 135, and a second filter 144 is installed between the second power supply 142 and the plurality of square tube electrodes 136.

  The first filter 143 passes the first high-frequency voltage current from the first power source 141 to the roll electrode 135 and grounds the second high-frequency voltage, and the second high-frequency voltage from the second power source to the first power source. Makes it difficult to pass current.

  On the contrary, the second filter passes the current of the first high-frequency voltage from the second power source 142 to the plurality of rectangular tube-shaped electrodes 136 to ground the first high-frequency voltage, and the first power source to the second power source. It is difficult to pass the current of the first high-frequency voltage to.

  The long base material F is unwound from the original winding (not shown) and is transported or is transported from the previous process, and is guided by the nip roll 165 via the guide roll 164 serving as the transport means for the base material F. Air or the like accompanying the substrate is cut off, transported into the film forming chamber 131, and transported between the plurality of rectangular tube electrodes 136 while being wound while being in contact with the roll electrode 135.

  Inside the film forming chamber 131, a high-frequency electric field is generated between the roll electrode 135 and the above-described voltages applied to a plurality of opposing rectangular tube-shaped electrodes 136 to form a discharge space 132, thereby forming a discharge space. The mixed gas G of the film forming gas and the discharge gas supplied to 132 is turned into plasma at atmospheric pressure or near atmospheric pressure, and the plasma mixed gas is exposed to the substrate F to form a thin film on the substrate. Is done.

  Here, the gas supply means 150 supplies the mixed gas G from the gas supply port 152 at a predetermined flow rate to the inside of the film forming chamber 131, particularly to the discharge space 132.

  Reference numerals 168 and 169 denote partition plates that separate the film forming chamber 131 from the outside.

  The waste gas Ga containing particles and the like that has been subjected to the discharge treatment is exhausted by the exhaust means 110 that exhausts the film forming chamber 131.

The film forming chamber 131 is provided with a sampling nozzle 121 for locally sucking the gas in the film forming chamber in order to measure the state of particles inside the film forming chamber.
For example, the number of particles of the waste gas Ga including the sampled particles is measured by the measuring unit 120 described later.

  Then, the blower 113 that exhausts the waste gas Ga containing particles inside the film forming chamber adjusts the exhaust amount according to the measured value by the control means 101 and removes the particles inside the film forming chamber.

  The base material F on which the thin film is formed passes through the nip roll 166 and the guide roll 167, and is taken up by a winder (not shown) or transferred to the next process.

  During the formation of the thin film, in order to heat or cool the roll electrode 135 and the plurality of rectangular tube electrodes 136, the medium whose temperature is adjusted by the electrode temperature adjusting means 160 is sent to both electrodes via the pipe 161 by the liquid feed pump P. Adjust the temperature from the inside of the electrode.

  The exhaust means and the measurement means according to the present invention will be described in detail below.

  The exhaust unit 110 includes an exhaust port 111 that discharges the processing waste gas Ga in the film forming chamber 131, a blower 113 whose exhaust amount is controlled by the control unit 101, and an exhaust path that connects the exhaust port 111 and the blower 113 ( 112) (hereinafter, the exhaust path is also referred to as an exhaust duct).

  Here, a plurality of exhaust ports 111 are provided in order to reliably and uniformly exhaust air from the film forming chamber, and a plurality of exhaust ducts 112 connected to each exhaust port are collected in one blower 113, and are controlled by the control means 101. The exhaust amount of the blower 113 is adjusted according to the measured value of the measuring means 120 described later, and the processing waste gas Ga in the film forming chamber 131 is discharged with the adjusted exhaust amount.

  Further, in order to discharge particles and the like reliably and efficiently, the exhaust port 111 is in the vicinity of the discharge space 132 where the particles are likely to be generated (for example, A part in FIG. 4), and the film forming chamber where the generated particles are likely to be stagnant. It is good to arrange in the area | region (for example, B section of FIG. 4) etc. where the flow of this gas stagnates.

  When one blower is provided, a plurality of measuring means for measuring the state of the particles, for example, the quantity, are provided, and the measured values are averaged by the control means, and the exhaust amount of the blower 113 is adjusted based on the average value.

The measuring means 120 measures the number of particles in the film forming chamber, and in order to detect particles and the like reliably and efficiently,
In the vicinity of the film forming region of the film where particles are likely to be generated (for example, part A in FIG. 4) and / or in the region where the air current in the thin film forming chamber in which the generated particles are likely to be stagnated (for example, part B in FIG. 4) A plurality of sampling nozzles 121 for sampling waste gas Gb including particles and the like,
A plurality of sensor heads 124 disposed in the middle of a sampling path 123 connecting a plurality of sampling nozzles 121 and a sampling means 122 described later, and detecting particles flowing in the sampling path;
The sampling means 122 for sucking (sampling) gas composed of a blower or the like having a constant flow rate;
The sensor amplifier 125 counts the quantity value of the detected particles and inputs it to the control means 101.

  As the sensor head 124, one that can detect particles having a diameter of 1 μm, preferably 0.5 μm is used, although it varies depending on the type of thin film to be formed.

  Here, the sensor head may directly measure the number of particles floating in the film forming chamber. In this case, the sensor head is disposed in the vicinity of the thin film forming region (for example, part A) in the film forming chamber 131 and / or manufactured. It arrange | positions in the area | region (for example, B section) where the airflow in a membrane chamber stagnates.

  Further, the exhaust capacity of the blower 113 is the maximum gas supply capacity that can be supplied by the gas supply means 150 in order to sufficiently cope with fluctuations in the required exhaust flow rate due to fluctuations in power supply voltage, gas supply, and gas distribution in the film forming chamber. Those having a capacity of about 1 to 10 times, preferably about 1 to 5 times are used.

  FIG. 9 is an explanatory diagram of the exhaust amount of the exhaust means.

  The horizontal axis indicates time t, and the vertical axis indicates the exhaust amount V of the exhaust means 110.

  For example, a is a time when the time has not passed since the start of thin film formation and the amount of particles is small, and the control means drives the blower with the same exhaust amount as when the exhaust amount is not controlled by the state of the particles.

  b is a time when the amount of particles has increased as the thin film is continuously formed, and the exhaust amount is increased in accordance with the amount of particles (number of particles) so as not to increase the amount of particles (number of particles) from a predetermined amount. .

  c is a time when particles are decreased due to an increase in the displacement, and the displacement is also decreased.

  d is a time when particles increase due to a decrease in the displacement, and the displacement also increases.

  Thereby, exhaust gas containing particles can be exhausted based on the actually measured number of particles.

  Although the example which provided the exhaust port in three places was demonstrated, you may provide for every sampling nozzle or each square tube type electrode, for example.

  FIG. 2 is a diagram for explaining another exhaust means.

  The illustration and description of the same parts as in FIG. 1 are omitted.

  In the middle of the exhaust duct 112 connected to the plurality of exhaust ports 111, the exhaust for adjusting the exhaust flow rate by the control means 101 according to the measured value of the measuring means for measuring the quantity of particles (not shown for the same reason as in FIG. 1). A flow rate control valve 115 may be provided to adjust the exhaust flow rate of each exhaust port 111, and exhaust gas from each exhaust flow rate control valve 115 may be collectively discharged by the blower 113a having a constant exhaust flow rate. .

  In this case, an exhaust capacity of the blower 113a having a capacity that is greater than (for example, 2 to 5 times) the total exhaust capacity of each exhaust flow rate control valve 115 is used.

  Each exhaust flow rate control valve 115 connected to each exhaust port 111 is based on the average value of the measured values of the number of particles of waste gas Gb collected from a plurality of sampling nozzles located in the vicinity of each exhaust port 111, respectively. The exhaust flow rate of each exhaust flow rate adjustment valve 115 is adjusted by the control means 101.

  Thereby, exhaust gas containing particles can be exhausted based on the actually measured number of particles.

  FIG. 3 is a view for explaining still another exhaust means.

  The illustration and description of the same parts as in FIG. 1 are omitted.

  A blower 113b for adjusting the exhaust flow rate by the control means 101 according to the measured value of the measuring means (not shown for the same as FIG. 1) for measuring the quantity of particles is provided in the exhaust duct 112 connected to the plurality of exhaust ports 111. It is also possible to exhaust the processing waste gas in the film forming chamber 131 by adjusting the exhaust flow rate of each exhaust port 111.

  In this case, the exhaust capacity of the blower 113b is a blower 113b having a smaller exhaust flow rate than the blower 113 described in FIG. 1 in which the entire exhaust is performed by a single blower.

  Further, the blower 113b connected to each exhaust port 111 has a control means based on the average value of the measured values of the number of particles of the waste gas Gb collected from a plurality of sampling nozzles located in the vicinity of each exhaust port 111, respectively. 101 is used to adjust the exhaust flow rate of each exhaust flow rate adjustment valve 115.

  Needless to say, the same exhaust flow rate may be provided although the cost increases.

  Thus, exhaust gas containing particles can be exhausted based on the actually measured number of particles.

  FIG. 4 is a view showing the electrode part of FIG.

  The two electrodes 240 of the plurality of rectangular tube electrodes 136 and the roll electrode 135 constitute a counter electrode, and a discharge space 132 is formed between them. The two electrodes 240 form a slit 242 that supplies a gas G containing a discharge gas and a thin film forming gas to the discharge space 132. The slit 242 is connected to the gas supply means 150 by a gas supply pipe 243. An outlet on the slit 242 side of the gas supply pipe 243 is a gas supply port 152.

  A thin film is formed on the base material F by exposing the base material F to the gas Gc that has been plasmatized in the discharge space 132.

  FIG. 5 is a perspective view showing an example of the structure of the conductive metallic base material of the roll electrode shown in FIG. 1 and the dielectric material coated thereon.

  In FIG. 5, a roll electrode 135 is formed by covering a conductive metallic base material 135A and a dielectric 135B thereon. In order to control the electrode surface temperature during the plasma discharge treatment, a temperature adjusting medium (for example, water or silicon oil) can be circulated inside the metallic base material 135A.

  FIG. 6 is a perspective view showing an example of the structure of the conductive metallic base material of the rectangular tube electrode and the dielectric material coated thereon.

  In FIG. 6, a rectangular tube-shaped electrode 136 has a coating of a dielectric 136B on a conductive metallic base material 136A as in FIG. 5, and the electrode 136 is formed of a metallic pipe so The temperature control medium can be circulated so that the temperature can be adjusted during discharge.

  Note that a plurality of rectangular tube-shaped electrodes 136 are installed along a circumference larger than the circumference of the roll electrode, and the discharge area of the electrodes is a full angle facing the rotating roll electrode 135. It is represented by the sum of the area of the cylindrical electrode surface.

  Although the rectangular tube electrode 136 may be a cylindrical electrode, the rectangular tube electrode is preferably used in the present invention because it has an effect of expanding the discharge range (discharge area) as compared with the cylindrical electrode.

  5 and 6, the roll electrode 135 and the rectangular tube electrode 136 are formed by spraying ceramics as dielectrics 135B and 136B on conductive metallic base materials 135A and 136A, respectively, and then sealing the inorganic compound. Is subjected to a sealing treatment. The ceramic dielectric may be a single-walled coating with a thickness of about 1 mm. As the ceramic material used for thermal spraying, alumina, silicon nitride, or the like is preferably used. Among these, alumina is particularly preferable because it is easily processed. Further, the dielectric layer may be a lining-processed dielectric provided with an inorganic material by glass lining.

  As the conductive metallic base materials 135A and 136A, titanium metal or titanium alloy, metal such as silver, platinum, stainless steel, aluminum, iron, etc., a composite material of iron and ceramics, or a composite material of aluminum and ceramics Among them, titanium metal or titanium alloy is particularly preferable.

  FIG. 7 is a schematic view showing another example of the thin film forming apparatus of the present invention.

  In FIG. 7, 10 is a plasma discharge vessel which is a film forming chamber, 11 is a square tube electrode composed of a plurality, 12 is disposed facing the square tube electrode 11, and is mounted with a sheet-like substrate F It is a ground electrode that also functions as a mounting base. A discharge space 13 is formed on the opposing surfaces of the rectangular tube electrode 11 and the ground electrode 12. The ground electrode 12 is configured to reciprocate in the direction of the arrow in the figure. By reciprocating the earth electrode 12 with respect to the rectangular tube electrode 11, it is possible to form a film having a larger area than the discharge space 13. In addition, even when there is non-uniform discharge in the reciprocating direction (substrate transport direction), there is an effect of leveling this, and as a result, uniform film formation in the reciprocating direction becomes possible.

  The gas G supplied to the discharge space 13 includes a discharge gas and a thin film forming gas. The gas G is filled into the plasma discharge vessel 10 from a gas supply means (not shown) through a gas supply tube. The outlet of the gas supply pipe is a gas supply port 25 in the figure. The gas G passes through the mesh 26 disposed in the plasma discharge vessel 10 so that the flow velocity is made uniform.

  When a high frequency voltage is applied from a high frequency power source 21 connected to the rectangular tube electrode 11, the gas G is turned into plasma in the discharge space 13. The base material F is exposed to the gasified gas Gc, and a thin film is formed on the base material F. Depending on the temperature of the substrate during plasma discharge treatment during thin film formation, the properties and composition of the resulting thin film may change, so the electrode is heated or cooled to an appropriate temperature by an electrode temperature adjusting means (not shown). It is desirable.

  Also in such a thin film forming apparatus, the exhaust means 110 shown in FIG. 1 and the measuring means 120 shown in FIG. Needless to say, particles inside the plasma discharge vessel 10 can be removed.

  Hereinafter, a control method of the thin film forming apparatus will be described using a flowchart.

  FIG. 8 is a flowchart for explaining a control method related to exhaust of particles in the thin film forming apparatus.

  Hereinafter, the control method related to the exhaust of particles will be described with reference to FIG. 8A and FIG. 1 regarding the first method.

  Step 1 The control means 101 drives the sampling means 122, and the gas Gb containing particles and the like by the plurality of sampling nozzles 121 including a plurality of sampling nozzles located in the vicinity of the film forming region and in the region where the airflow in the film forming chamber stagnates. To suck.

  Then, the particles in the gas Gb passing through the plurality of sampling paths 123 within a predetermined time are detected by each sensor head 124, the number of detected particles is counted by the sensor amplifier 125, and the measured value (count) of each sensor amplifier is counted. Value) is input to the control means 101 and step 2 is performed.

  Step 2 The control means 101 stores the inputted measurement value (count value) of the sensor amplifier in the storage means 102 and calculates the average value by calculating the measurement values of all sampling nozzles measured at substantially the same time. Step 3

  Step 3 The control means 101 reads out from the storage means a pre-stored table describing the exhaust amount of the blower with respect to the average value of the number of particles of all the sensor amplifiers, and proceeds to Step 4.

  Step 4 The control means 101 reads the exhaust amount corresponding to the average value calculated in Step 2 from the read table, determines the exhaust amount value, and proceeds to Step 5.

Step 5 The control means 101 inputs an exhaust command value to the blower 113 based on the determined exhaust amount value,
The blower 113 exhausts an amount corresponding to the input exhaust command value, and sucks / excludes waste gas containing particles in the film forming chamber 131 from the exhaust port 111 through the exhaust duct 112, and advances to the end. To do.

  Next, the second method will be described with reference to FIG. 8B and FIG.

  Step 1 The description is omitted because it is the same as the first method.

  Step 2 The control means 101 stores the measurement value of the sensor amplifier input in Step 1 in the storage means 102, and for each of a plurality of predetermined areas (for example, each outlet) measured at substantially the same time from the stored measurement value. The measured values in the vicinity of the film forming region near each and the region where the airflow in the film forming chamber stagnates are read out, the average value is obtained, and the process proceeds to step 3.

  Step 3 The control means 101 reads a table describing the exhaust amount of the exhaust control valve 115 with respect to the average value obtained in Step 2 from the storage means, and proceeds to Step 4.

  Step 4 The control means 101 reads the exhaust amount corresponding to the average value calculated in Step 2 from the read table, determines the read exhaust amount as a necessary exhaust amount value, and proceeds to Step 5.

Step 5 The control means 101 drives the blower 113a and inputs the determined exhaust amount value to the exhaust control valve 115,
Waste gas containing particles in the film forming chamber 131 is removed from each exhaust port 111 by the blower 113a through each exhaust control valve 115 for exhausting an amount corresponding to the exhaust amount value, and the process proceeds to the end.

  Thus, for each exhaust port, exhaust gas containing particles in the vicinity of the film forming region near each exhaust port and in the region where the airflow in the film forming chamber stagnates can be exhausted.

  Next, the third method will be described with reference to FIG. 8C and FIG.

  Step 1 The description is omitted because it is the same as the first method.

  Step 2 The explanation is omitted because it is the same as the second method.

  Step 3 The control means 101 reads out from the storage means a table describing the exhaust amount of the blower 113b with respect to the average value obtained in Step 2, and proceeds to Step 4.

  Step 4 The description is omitted because it is similar to the second method.

  Step 5 The control means 101 inputs the determined exhaust amount values to the plurality of blowers 113b, each of the blowers 113b exhausts an amount corresponding to the input exhaust command value, and from the exhaust port 111 through the exhaust duct 112, The waste gas containing particles in the film forming chamber 131 is sucked and removed, and the process proceeds to the end.

  Thus, for each exhaust port, exhaust gas containing particles in the vicinity of the film forming region near each exhaust port and in the region where the airflow in the film forming chamber stagnates can be exhausted.

  The configuration of the thin film forming apparatus described above and the control method thereof enable exhaust of waste gas containing particles based on the number of particles actually measured, and does not require high-precision flow rate control, and has a simple structure. In addition, it is possible to provide a thin film forming apparatus that is small, inexpensive, easy to maintain, a method for controlling the exhaust means of the thin film forming apparatus, and a method for producing a substrate on which a thin film is formed.

  FIG. 10 is an explanatory diagram of a method for producing a substrate on which a thin film is formed.

  The thin film forming apparatus 100 has the configuration described in FIG. 1, FIG. 2, or FIG. 3, and the exhaust unit is controlled by the control method described in the flow of FIG. 8. For this reason, the thin film forming apparatus 100 is kept to the minimum necessary source.

  A cleaning room 50 is filled with clean air by a dust removing device (not shown) that removes dust and the like.

  A plurality of thin film forming apparatuses 100 are installed in a straight line in the cleaning room 50, and a web-like base material F is continuously transported in the direction of the arrow by a base material transport apparatus (not shown). Be transported.

  Then, each thin film forming apparatus 100 sequentially forms a thin film on the base material to have a predetermined thickness.

  In the thin film forming apparatus 100, the mixed gas of the film forming gas and the discharge gas formed into plasma is exposed on the substrate F conveyed to the film forming chamber 131 or on the thin film formed by the upstream thin film forming apparatus, A thin film is formed.

During the formation of the thin film, the quantity of the state of particles generated in the film forming chamber 131 is measured by the measuring means described above,
Based on the measured value, the control unit described above adjusts the exhaust amount of the exhaust unit described above, and particles are discharged together with the waste gas.

  Note that the waste gas containing particles is cleaned and discharged outside the cleaning room.

It is the schematic which shows an example of the thin film forming apparatus of this invention. It is a figure explaining another exhausting means. It is a figure explaining other exhausting means. It is the figure which took out the electrode part of FIG. It is a perspective view which shows an example of the structure of the electroconductive metal base material of the roll electrode shown in FIG. 1, and the dielectric material coat | covered on it. It is a perspective view which shows an example of the structure of the electroconductive metal preform | base_material of a rectangular tube type electrode, and the dielectric material coat | covered on it. It is the schematic which shows another example of the thin film forming apparatus of this invention. It is a flowchart explaining the control method which concerns on the exhaust of the particle | grains of a thin film forming apparatus. It is explanatory drawing of the exhaust_gas | exhaustion amount of an exhaust means. It is explanatory drawing of the production method of the board | substrate which formed the thin film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Thin film forming apparatus 101 Control means 110 Exhaust means 113, 113a, 113b Blower 115 Exhaust control valve 120 Measuring means 121 Sampling nozzle 122 Sampling means 124 Sensor head 125 Sensor amplifier 131 Film forming chamber 132 Discharge space 135 Roll electrode 136 Square tube type electrode 150 Gas supply means 152 Gas supply port F Base material G Gas

Claims (10)

Under atmospheric pressure or near atmospheric pressure, a high frequency electric field is generated between the opposing electrodes to form a discharge space, and the mixed gas of the film forming gas and the discharge gas supplied to the discharge space is turned into plasma. Generated in the film forming chamber, a film forming chamber for exposing the plasma mixed gas to the substrate to form a thin film on the substrate, a mixed gas supplying means for supplying the mixed gas into the film forming chamber, and In a thin film forming apparatus having exhaust means for exhausting waste gas containing particles and the like,
A thin film forming apparatus comprising: exhaust means for measuring a state of suspended particles such as particles in the film forming chamber and dust and controlling an exhaust amount of the exhaust means according to the measurement result. The thin film forming apparatus according to claim 1, wherein the state of suspended particles such as particles and dust is measured by measuring the number of suspended particles such as particles and dust. The exhaust means includes at least one exhaust port for exhausting the waste gas inside the film forming chamber;
The thin film forming apparatus according to claim 1, further comprising: a single exhaust member connected to the exhaust port via an exhaust path, the exhaust amount of which is controlled by a control unit. The exhaust means includes at least one exhaust port for exhausting the waste gas inside the film forming chamber;
At least one exhaust amount adjusting means connected to the exhaust port via an exhaust path, the exhaust amount being controlled by the control means;
The thin film forming apparatus according to claim 1, further comprising a single exhaust member connected to the exhaust amount adjusting unit via an exhaust path. The exhaust means includes a plurality of exhaust ports for exhausting the waste gas inside the film forming chamber;
The thin film forming apparatus according to claim 1, further comprising: a plurality of low exhaust amount exhaust members that are connected to the exhaust port via an exhaust path and whose exhaust amount is controlled by a control unit. The said measurement means is provided with the detection means which detects floating particles, such as particles, and dust, and the counter which counts the quantity of suspended particles, such as detected particles, and dust, The any one of Claims 1-5 characterized by the above-mentioned. 2. The thin film forming apparatus according to item 1. The detection means is detection means for detecting floating particles and dust such as particles in the waste gas sampled by sampling means for sampling the waste gas at least in the vicinity of the discharge space. 7. The thin film forming apparatus according to 6. The high frequency electric field generated between the opposing electrodes is a superposition of the first high frequency electric field and the second high frequency electric field,
The frequency ω2 of the second high frequency electric field is higher than the frequency ω1 of the first high frequency electric field,
The relationship between the first high-frequency electric field strength E1, the second high-frequency electric field strength E2, and the discharge starting electric field strength IE is:
E1 ≧ IE> E2
Or E1> IE ≧ E2
The thin film forming apparatus according to claim 7, wherein an output density of the second high frequency electric field is 1 W / cm ² or more. Under atmospheric pressure or near atmospheric pressure, a high frequency electric field is generated between the opposing electrodes to form a discharge space, and the mixed gas of the film forming gas and the discharge gas supplied to the discharge space is turned into plasma. A film forming chamber for forming the thin film on the substrate by exposing the plasma mixed gas to the substrate, mixed gas supply means for supplying the mixed gas into the film forming chamber, and waste gas in the film forming chamber In the control method of the exhaust means of the thin film forming apparatus having the exhaust means for exhausting
Measuring the quantity of the state of particles generated in the film forming chamber;
Determining an exhaust amount corresponding to the measured value from information of each exhaust amount of the exhaust means for each measured value of the quantity of particle states stored in advance;
And a step of driving the exhaust unit based on the determined exhaust amount to exhaust the waste gas containing particles. A plurality of thin film forming devices according to claim 6 are provided in a clean room, and a plurality of thin film forming devices according to claim 6 are formed while exhausting waste gas containing particles according to the state of particles generated in the thin film forming device. A method for producing a substrate in which a thin film having a predetermined thickness is formed on a base material by continuously conveying a web-like base material to the apparatus.

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