JP4121320B2 - Remote plasma cleaning device for deposition chamber - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a remote plasma cleaning apparatus for a deposition chamber. Specifically, the remote of the deposition chamber used to clean the inside of the deposition chamber of a film forming apparatus used in various semiconductor and flat display manufacturing processes such as chemical vapor deposition (for example, plasma CVD) and a sputtering apparatus. The present invention relates to a plasma type cleaning apparatus.
[0002]
[Prior art]
  For example, in plasma CVD, a substrate is placed in a vacuum deposition chamber having a pair of thin plate parallel electrodes, a reactive gas is flowed into the deposition chamber through the upper electrode, and a radio frequency (RF) voltage is applied to the pair of parallel electrodes. By generating plasma in the reaction gas, the reaction gas is decomposed and a material such as silicon nitride (SiN) is deposited on the surface of the substrate to manufacture a predetermined semiconductor product.
[0003]
  In a film forming apparatus used in such a semiconductor or flat display manufacturing process, a material such as silicon nitride is designed to be preferentially deposited on the substrate surface. Therefore, it is difficult to avoid that a part of the material is deposited on the components exposed to the surface, and therefore, it is necessary to perform cleaning to remove the material deposition layer which is accumulated in the chamber by repeated use of the deposition chamber. .
[0004]
  As a cleaning means for this kind of deposition chamber, a method that has been generally adopted in the past is that a precursor gas is directly introduced into the deposition chamber and a glow discharge plasma is generated in the deposition chamber. Is applied locally to the precursor gas to generate reactively excited species, which form a volatile compound with the material deposition layer in the chamber to clean the surface inside the chamber. This is an in-situ cleaning method (common name: in-situ cleaning method).
[0005]
  However, in-situ cleaning methods such as those described above generate plasma in the deposition chamber to generate reactively excited species, so that a cleaning rate that does not reduce product productivity is obtained. Requires a high level of output, and the higher the output level, the greater the damage to the hardware inside the deposition chamber and the shorter the useful life of the deposition chamber itself. The cost per substrate of the manufactured product increases. In addition, because the power level is set high, residues and by-products that can damage other system components and parts, or can only be removed by physical means such as wiping, are inside the chamber. There is a problem that occurs.
[0006]
  As a cleaning means for solving such various problems of the conventional general in-situ cleaning method, as disclosed in, for example, Japanese Patent Application Laid-Open No. 10-149899, etc., it is separated from the deposition chamber. A plasma is generated in a separate chamber installed at a remote location to activate a precursor gas supplied to the remote chamber to generate a reactive excited species, and this reactive excited species is introduced into the deposition chamber Thus, a remote plasma type cleaning apparatus for cleaning the inside of the deposition chamber has been proposed.
[0007]
  By the way, as a high frequency power generation source (power source) for plasma generation in a conventionally proposed remote plasma type cleaning apparatus, conventionally, a fixed frequency oscillator whose oscillation frequency is assigned for industrial use and the like, The output impedance of the high-frequency power applied to the high-frequency discharge tube under a fixed oscillation frequency is variably controlled to automatically match the load impedance of the high-frequency discharge tube through a phase / impedance adjustment mechanism such as a servo motor. A device provided with a high-frequency power matching circuit has been used.
[0008]
[Problems to be solved by the invention]
  However, in this type of remote plasma cleaning device, the type and concentration of the precursor gas used, changes in the operating pressure range, etc., or fluctuations in capacitance under transient conditions where the plasma is unstable before and after ignition of the discharge plasma, etc. As a result, the load impedance is likely to fluctuate. In particular, in the case of the remote plasma method, in order to increase the plasma generation efficiency in the remote chamber, the frequency effect of the high frequency power applied to the high frequency discharge tube is set high, so the skin effect is remarkable and the high frequency discharge Large fluctuation in tube load impedance. In order to cope with such fluctuations in load impedance, the conventional remote plasma cleaning device establishes a resonance condition for the capacitance or inductance, which is a component of the high-frequency power matching circuit, via a phase / impedance adjustment mechanism such as a servo motor. Because the output impedance is automatically matched to the load impedance by adjusting so that many mechanical elements are required, not only the cost increase and the size of the apparatus are unavoidable, but also a movable mechanical element such as a servo motor. It takes time to complete alignment due to the influence of inertia of the material and lacks responsiveness to generate stable plasma.As a result, the processing time under unstable plasma is not only long, The time required for alignment is the roster for a given cleaning process. A beam, which leads to deterioration of the cleaning performance.
[0009]
  Furthermore, if the frequency of the electric power applied to the high-frequency discharge tube remains fixed at a high value, the electrode itself generates heat due to the skin effect, and not only the electrode but also the remote chamber, the deposition chamber, and a tube connecting both chambers, etc. There is also a problem that the durability (lifetime) of the whole apparatus is shortened due to wear and damage of movable mechanical elements such as a servo motor and a link mechanism operating in conjunction with the servo motor.
[0010]
  The present invention has been made in view of the above circumstances, while suppressing deterioration in durability due to burnout, wear and damage of electrodes, etc., wear of movable mechanical elements, and the like, while making the whole compact and low cost. An object of the present invention is to provide a deposition chamber remote plasma cleaning device that improves the response to sudden fluctuations in load impedance, stabilizes the plasma quickly, and performs a predetermined cleaning process with high performance and efficiency. Yes.
[0011]
[Means for Solving the Problems]
  In order to achieve the above object, a remote plasma cleaning apparatus for a deposition chamber according to the present invention has an inductively coupled high frequency discharge electrode wound in a spiral coil around the outer periphery of an insulating tubular container to which a precursor gas is supplied. A high-frequency discharge tube configured to rotate, a high-frequency power generation source for generating plasma in the container by applying high-frequency power to a coiled high-frequency discharge electrode of the high-frequency discharge tube, and an output of the high-frequency power generation source A high-frequency power matching circuit that matches the impedance to the load impedance of the high-frequency discharge tube, and activates the precursor gas by the plasma generated in the tubular vessel to generate reactive excited species, and this reactive excited species Is installed in the deposition chamber to clean the interior of the deposition chamber. A large-diameter conductive metal tube wound in a spiral coil around the outer periphery of an insulating tubular container in a state in which cooling water can flow through the electrode, and the large-diameter conductive electrode A small-diameter high-frequency power line that is disposed between the helical pitches of the conductive metal tube and wound in a spiral coil around the outer periphery of the insulating tubular container, on the exhaust gas outlet side of the large-diameter conductive metal tube The end and the end on the exhaust gas inlet side of the small-diameter high-frequency power line are electrically connected, and the above-mentioned high-frequency power matching circuit is a fixed type that holds the impedance fixed at a preset value or a semi-fixed that can be finely adjusted manually. The oscillator of the high frequency power generation source is configured to be a variable frequency type, and the output impedance of the high frequency power generation source is matched to the load impedance by the oscillation frequency of the oscillator. It is characterized in that control to the frequency control circuit is provided.
[0012]
  According to the present invention having the above-described characteristic configuration, the high-frequency discharge electrode for generating plasma is wound around the outer periphery of the insulating tubular container in a spiral coil shape and disposed outside the plasma region. It is possible to reduce as much as possible the wear and damage to the electrodes, etc., caused by the direct contact of the high-frequency discharge electrode and its protective material with fluorine radicals and fluorine ions generated due to the presence of excited NF3, etc. In addition, the high-frequency power matching circuit is configured as a fixed type or semi-fixed type and does not use movable mechanical elements that are easily worn or damaged, such as a servo motor. Is possible. In addition, changes in the type and concentration of the precursor gas used, the operating pressure range, etc., or fluctuations in capacitance under transient conditions before and after discharge plasma ignition, and plasma generation efficiency in a remote chamber If the load impedance suddenly fluctuates due to the effect of the skin effect associated with the use of high frequency power applied to the high frequency discharge tube to increase the Components of a high-frequency power matching circuit using mechanical elements such as a servo motor and its control circuit by controlling the oscillation frequency of the oscillator in the power generation source so that the output impedance of the high-frequency power generation source is matched to the load impedance The capacitance or inductance is so that the resonance condition is satisfied Compared to conventional devices that adjust the dynamics, the entire device is made compact and low-cost, and discharge plasma can be generated stably by following responsiveness to sudden fluctuations in load impedance. Can be quickly and stably maintained to perform a predetermined cleaning process with high performance and efficiency.
[0013]
  In the remote plasma cleaning apparatus for a deposition chamber according to the present invention having the above-described configuration, the reflected wave of the high-frequency power applied to the high-frequency discharge electrode is detected, and the detected reflected wave power is previously detected. When the reflected wave power generated at the time of the cleaning process by the remote plasma is increased above the set value by adding a traveling wave power suppression circuit that reduces the traveling wave power of the high frequency power when the set value is exceeded, Lowering the traveling wave power, that is, limiting the effective power to rise above a certain level, and protecting the high frequency power generation source without requiring a special power adjustment device or magnetic field application device, etc. Can be further improved, and adverse effects on the vicinity of the power generation source can be avoided.
[0014]
  In the remote plasma cleaning apparatus for a deposition chamber according to the present invention having the above-described configuration, the output impedance of the high-frequency power generation source is matched with the load impedance of the oscillation frequency of the oscillator of the high-frequency power generation source. By attaching a frequency switching circuit that can be switched between a state that is variably controlled and a state that is fixed to the set frequency, the impedance of the load is subject to abrupt fluctuations, such as before plasma ignition or immediately after ignition. Then, by switching the oscillation frequency of the oscillator to the variable control state, the plasma can be quickly stabilized by quickly responding to fluctuations in the load impedance, and the predetermined cleaning process can be performed efficiently, as well as after the plasma ignition. , Because the precursor gas is constantly supplied If the oscillation frequency of the oscillator is switched to a fixed state under conditions where there is no fluctuation in the oscillation or very little fluctuation, the unstable elements associated with variable feedback control of the oscillation frequency can be eliminated, and a predetermined cleaning process can be performed. Two usage modes, a state in which the oscillation frequency is variably controlled and a state in which the oscillation frequency is fixed, can be arbitrarily selected so that it can always be performed properly and stably.
[0015]
  Furthermore, the high-frequency discharge tube in the remote plasma cleaning apparatus for a deposition chamber according to the present invention having the above-described configuration is configured by winding an inductively-coupled high-frequency discharge electrode in a spiral coil around the outer periphery of an insulating tubular container. As described in claim 1, the high-frequency discharge electrode is a large-diameter conductive coil wound around the outer periphery of an insulating tubular container in a state in which cooling water can flow therethrough. A large-diameter conductive metal tube, and a small-diameter high-frequency power line disposed between the helical pitches of the large-diameter conductive metal tube and wound in a spiral coil around the outer periphery of the insulating tubular container. The end of the metal tube on the exhaust gas outlet side and the end of the small-diameter high-frequency power line on the exhaust gas inlet side are electrically connected.
[0016]
  ThisTherefore, even if the frequency of the power applied to the electrode is set high to increase the plasma generation efficiency by inductive coupling by circulating cooling water inside the large-diameter conductive metal tube at the time of plasma generation, While suppressing heat generation and reducing power loss, it is possible to further improve the durability of the entire apparatus by preventing burning of electrodes, a high-frequency discharge tube serving as a remote chamber, and a tube connecting between the deposition chamber and the like. . In addition, since the small-diameter high-frequency power line is disposed in the dead space between the helical pitches of the large-diameter conductive metal tube, the cooling action for the small-diameter high-frequency power line is maintained, and while using a short-length high-frequency discharge tube, The number of turns of the entire high-frequency discharge electrode can be increased, and the reduction in effective power for stable plasma generation and the durability of the electrode can be further improved.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to the drawings.
  FIG. 1 is a schematic configuration diagram of an entire deposition chamber remote plasma type cleaning apparatus according to the present invention. For example, fluorination of PCF (perfluorinated carbon) gas such as CF4, C2 F6, C3 F8, C6 F14, NF3, etc. Precursor gas G selected from nitrogen gas, fluorinated sulfur gas such as SF6, and mixed gas thereof can be supplied, and this precursor gas G is activated and activated as plasma is generated. A high-frequency discharge tube 1 (remote chamber) capable of generating excited species is installed at a remote position at an appropriate distance from a deposition chamber 2 of a film forming apparatus used in various semiconductor and flat display manufacturing processes. Has been. The deposition chamber 2 and the high-frequency discharge tube 1 are connected via a pipe 3, and unnecessary material is removed from the reactive excited species before being introduced into the deposition chamber 2 in the middle of the pipe 3. A filter 4 is interposed.
[0018]
  As shown in FIG. 2, the high-frequency discharge tube 1 has a supply port 5a for the precursor gas G and a discharge port 5b for reactive excited species connected to the pipe 3, for example, a heat-resistant ceramic or quartz glass. Plasma is generated in the tubular container 5 by applying a high-frequency power from an insulating tubular container 5 such as the like and a spiral coil wound around the outer periphery of the insulating tubular container 5 to be described later. Inductive coupling type high-frequency discharge electrode 7 is possible.
[0019]
  Here, as an example of the high-frequency discharge electrode 7, as clearly shown in FIG. 3, for example, the electrode 7 is wound around the outer periphery of the insulating tubular container 5 in a spiral coil shape so that the cooling water CW can be circulated therein. A large-diameter conductive metal tube 8 such as a copper tube and a dead coil between the spiral pitches of the large-diameter conductive metal tube 8 are arranged one by one on the outer periphery of the insulating tubular container 5. The small-diameter high-frequency power line 9 such as a litz wire wound in the shape of a large-diameter conductive metal tube 8 on the exhaust gas outlet 5b side end 8b and the small-diameter high-frequency power line 9 on the exhaust gas inlet 5a side. Of the large-diameter conductive metal tube 8 on the side of the exhaust gas inlet 5a and the end portion of the small-diameter high-frequency power line 9 on the side of the exhaust gas outlet 5b. 9b is connected to the high-frequency power source 8, thereby 7 used that constitutes the coil turns of the whole to twice the number of turns of the coils of the large 径導 conductive metal tube 8.
[0020]
  FIG. 4 is a configuration diagram of a high-frequency power generation source (power source) 6 that applies high-frequency power to the high-frequency discharge electrode 7 of the high-frequency discharge tube 1 in the deposition chamber remote plasma cleaning apparatus having the above basic configuration. In the figure, reference numeral 11 denotes a frequency variable crystal oscillator whose oscillation frequency has a center frequency of 2 MHz or 4 MHz and is within a range of ± 0.5 MHz with respect to the center frequency, that is, 1.5 to 2.5 MHz. It is configured to be variably controllable in the range of 3.5 to 4.5 MHz. Reference numeral 12 denotes a phase-locked loop (PLL) that variably controls the oscillation frequency of the oscillator 11 at a center frequency of 2 MHz or 4 MHz and in the above range (1.5 to 2.5 MHz or 3.5 to 4.5 MHz). When the frequency switching circuit 13 configured to be switched to the state is switched to the fixed frequency side, the output frequency is fed back to automatically adjust the oscillation frequency to a fixed frequency necessary for generating discharge plasma. Yes.
[0021]
  Reference numerals 14 and 15 denote power amplifiers, which use an operational amplifier 18 to calculate a deviation between the set power Ptf preset by the power setter 16 and the traveling wave power Pf detected and fed back by the power directional coupler 17. Based on the output signal of the effective power automatic adjustment circuit 19 that calculates the power amplification factor corresponding to the deviation, the oscillation frequency is amplified and the high frequency power is output. The operational amplifier 22 calculates a deviation between the reflected wave power Pr detected and fed back by the power directional coupler 17 and the set reflected wave power Ptr whose upper limit is set in advance by the reflected power setting unit 21. This is a traveling wave power suppression circuit that reduces (droops) traveling wave power so that the deviation is less than or equal to zero, and a high-frequency power generation source (power source) 6 is configured by each of the above components 11 to 22.
[0022]
  Reference numeral 23 denotes a V-I phase difference detection circuit for detecting a phase difference between the voltage V and the current I of the high-frequency power. When the frequency switching circuit 13 is switched to the frequency variable side, this V-I phase difference detection circuit The oscillation frequency of the oscillator 11 based on the detection signal S from the operational amplifier 26 that detects the phase difference between the voltage and current of the high-frequency power generated by the power supply 23 is in the above-described range (1.5 to 2.5 MHz or 3.5 to 4.5 MHz. The voltage variable frequency control circuit (VCO) 24 that is variably controlled in () is interposed in the feedback system of the frequency variable loop. Reference numeral 25 denotes a high-frequency power matching circuit composed of a capacitance and an inductance, which matches the output impedance of the high-frequency power generation source (power source) 6 with the load impedance of the high-frequency discharge tube 1. The fixed value is fixedly held at a preset value, or is semi-fixed that can be finely adjusted manually.
[0023]
  According to the deposition chamber remote plasma cleaning apparatus configured as described above, the precursor gas G is supplied into the insulating tubular container 5 of the high-frequency discharge tube 1 and the high-frequency power generation source (power source) 6 generates a high frequency. By applying a high frequency power of about 2 MHz or 4 MHz to the discharge electrode 7 to generate plasma in the tubular vessel 5 by inductive coupling, the precursor gas G is activated and reactive excited species such as ions and radicals. Is generated. This reactive excited species is passed through the filter 4 before being introduced into the deposition chamber 2 through the pipe 3, and unnecessary materials such as particulate matter and reaction by-products contained in the reactive excited species. Is removed, and is introduced into the deposition chamber 2, and a predetermined cleaning process for removing the material deposition layer adhering to the inner wall surface of the chamber 2 and the components exposed in the chamber 2 by the etching action. Is done.
[0024]
  During the cleaning process in the deposition chamber 2 by such inductively coupled remote plasma, the frequency switching circuit 13 is normally switched to the variable frequency side, and the type and concentration of the precursor gas G to be used, the operating pressure range, etc. When the load impedance changes suddenly due to the change of the capacitance of the high-frequency discharge tube 1 or the like under a transient condition where the plasma before and after plasma ignition is unstable, the voltage and current of the high-frequency power by the VI phase difference detection circuit 23 The phase difference detection signal S is fed back to the voltage variable frequency control circuit (VCO) 24, and the oscillation frequency of the oscillator 11 of the high frequency power generation source 6 is changed to the load impedance according to the feedback signal. 6 is variably controlled to match the output impedance of 6. As a result, even if the high-frequency power matching circuit 25 is of a fixed type or a semi-fixed type, the discharge plasma is promptly generated by following the rapid fluctuation of the load impedance with good response, and the generated discharge plasma is stable. The predetermined cleaning process can be performed with high performance and efficiency while maintaining the state.
[0025]
  In the cleaning process, the reflected wave of the high-frequency power applied to the high-frequency discharge electrode 7 is always detected, and when the detected reflected wave power Pr becomes equal to or higher than a preset value Ptr, the traveling wave The traveling wave power Pf can be lowered (drooped) through the power suppression circuit 20 so that the deviation is less than or equal to zero, whereby the reflected wave power that is unavoidable during the cleaning process using the discharge plasma is set to the set value. The increase in traveling wave power accompanying the increase, that is, the abnormal increase in effective power can be suppressed, the high frequency power generation source 6 can be protected, and the durability of the entire apparatus can be improved. An adverse effect on the vicinity of the generation source 6 can be avoided.
[0026]
  Further, by allowing the cooling water CW to circulate inside the large-diameter conductive metal tube 8 constituting the high-frequency discharge electrode 7 of the high-frequency discharge tube 1, the frequency of the electric power applied to the electrode 7 exceeds 2 MHz or 4 MHz. Even if it is set to a high value, the heat loss due to the skin effect can be suppressed and the power loss can be reduced, and the electrode 7, the high-frequency discharge tube 1 and the piping 3 can be prevented from being burned and their durability can be improved. In addition, since the small-diameter high-frequency power line 9 is disposed in the dead space between the helical pitches of the large-diameter conductive metal tube 8, the cooling effect on the small-diameter high-frequency power line 9 is maintained well, and the overall length L of the high-frequency discharge tube 1 is reduced. It is possible to increase the number of coil turns of the entire high-frequency discharge electrode 7 while shortening the size of the entire apparatus, thereby reducing the plasma ignition power and improving the durability of the electrode 7. Can be planned.
[0027]
  In the above embodiment, in order to explain the response operation under the condition that the load impedance of the high-frequency discharge tube 1 is likely to fluctuate rapidly, such as the change of the type of the precursor gas or from immediately before plasma ignition to immediately after ignition. In addition, the frequency switching circuit 13 is switched to the variable control side and used. However, under the condition that the precursor gas is constantly supplied and the load impedance does not vary or the variation is very small as after plasma ignition. By switching the frequency switching circuit 13 to the fixed side and using it, the unstable element accompanying the feedback variable control of the oscillation frequency is eliminated, and the plasma is always stably maintained, and a predetermined cleaning process is performed for the residue and by-product. It can always be performed reliably and properly in a state where there is no occurrence.
[0028]
【The invention's effect】
  As described above, according to the present invention, it is possible to reduce the wear and damage of the electrode and its protective material as much as possible by adopting the inductively coupled high-frequency discharge electrode, and fixed or semi-fixed high-frequency power matching. By using the circuit and eliminating the use of movable mechanical elements such as servo motors that are likely to be worn, damaged or broken down, the durability of the entire apparatus can be significantly improved. In addition, changes in the type and concentration of the precursor gas used, the operating pressure range, etc., or fluctuations in capacitance under transient conditions where the plasma is unstable before and after plasma ignition, and also in order to increase the plasma generation efficiency, For sudden fluctuations in load impedance due to the effect of the skin effect associated with setting the frequency of the high-frequency power applied to the discharge tube high, the oscillation frequency of the oscillator of the high-frequency power generation source is variably controlled. The output impedance of the power generation source can be matched to the load impedance, making the entire device more compact and lower in cost than using a conventional automatic matching circuit that requires mechanical elements such as a servo motor. The discharge plasma can be made faster by following the rapid fluctuation of the load impedance with good responsiveness. Causes generated, by maintaining the generated plasma is always in a stable state is an effect that a predetermined cleaning treatment can be performed very high performance and efficiency.
[0029]
  Further, by adding the traveling wave power suppression circuit as described in claim 2, an effective power abnormality caused by an increase in reflected wave power that cannot be avoided during the cleaning process using remote plasma exceeds a set value. Without increasing the power consumption, and without requiring a special power adjustment device or magnetic field application device, the high-frequency power generation source can be protected to further improve the durability of the entire device, and adverse effects on the periphery of the power generation source can be achieved. Can be avoided.
[0030]
  Further, by providing the frequency switching circuit as claimed in claim 3, under the condition that the load impedance is likely to fluctuate rapidly, the effect of improving the responsiveness of early ignition and stable maintenance of the plasma is obtained, and after the plasma ignition If there is no fluctuation in load impedance, or if the fluctuation is very small, the oscillation frequency of the oscillator is switched to a fixed state to eliminate unstable elements associated with variable feedback control of the oscillation frequency. A reliable and appropriate cleaning process can always be performed without generation of products and by-products.
[0031]
  Further, since the high-frequency discharge tube having the structure described in claim 1 is used, even if the frequency of the power applied to the electrode is set high in order to increase the plasma generation efficiency by inductive coupling, heat generation due to the skin effect As a result, it is possible to reduce power loss and prevent burnout of electrodes, high-frequency discharge tubes, pipes, and the like, thereby further improving their durability, and thus the durability of the entire apparatus. In addition, since the small-diameter high-frequency power line is arranged in the dead space between the helical pitches of the large-diameter conductive metal tube, the cooling action for the small-diameter high-frequency power line is maintained, and the high-frequency discharge tube with a short overall length is used. The number of turns of the entire discharge electrode can be increased, and the effective power for stable plasma generation can be reduced and the durability of the electrode can be further improved.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an entire remote plasma cleaning apparatus for a deposition chamber according to the present invention.
FIG. 2 is a front view showing a configuration of a high-frequency discharge tube in the apparatus.
FIG. 3 is an enlarged front view of the main part of FIG. 2;
FIG. 4 is a configuration diagram of a high-frequency power generation source in the apparatus.
[Explanation of symbols]
  1 High frequency discharge tube (remote chamber)
  2 Deposition chamber
  3 Connection piping
  5 Insulating tubular container
  6 High-frequency power source
  7 High frequency discharge electrode
  8 Large-diameter conductive metal tube
  9 Small diameter high frequency power line
  11 Frequency variable oscillator
  13 Frequency switching circuit
  20 Reflected power suppression circuit
  24 Frequency control circuit
  25 High frequency power matching circuit
  G Precursor gas

Claims (3)

A high frequency discharge tube configured by winding an inductive coupling type high frequency discharge electrode in a spiral coil around the outer periphery of an insulating tubular container to which a precursor gas is supplied, and a coiled high frequency discharge electrode of the high frequency discharge tube A high frequency power generating source for generating plasma in the container by applying a high frequency power to the container, and a high frequency power matching circuit for matching an output impedance of the high frequency power generating source to a load impedance of the high frequency discharge tube, A deposition chamber configured to activate a precursor gas by plasma generated in a vessel to generate reactive excited species, introduce the reactive excited species into the deposition chamber, and clean the interior thereof. A remote plasma cleaning device,
The high-frequency discharge electrode has a large-diameter conductive metal tube wound in a spiral coil around the outer periphery of the insulating tubular container in a state in which cooling water can flow therein, and a spiral of the large-diameter conductive metal tube A small-diameter high-frequency power line arranged between the pitches and wound around the outer periphery of the insulating tubular container in a spiral coil shape, and an end on the exhaust gas outlet side of the large-diameter conductive metal tube and a small-diameter high-frequency power line Is electrically connected to the end of the exhaust gas inlet side of the
The high-frequency power matching circuit is configured as a fixed type that holds the impedance fixed at a preset value or a semi-fixed type that can be finely adjusted manually, and the oscillator of the high-frequency power generation source is configured as a variable frequency type. A remote plasma cleaning apparatus for a deposition chamber, characterized in that a frequency control circuit is provided for controlling the oscillation frequency of the oscillator so that the output impedance of the high frequency power generation source is matched with the load impedance.   A traveling wave power suppression circuit is provided for detecting a reflected wave of the high frequency power applied to the high frequency discharge electrode and reducing the traveling wave power of the high frequency power when the detected reflected wave power exceeds a preset value. The remote plasma cleaning device for a deposition chamber according to claim 1.   A frequency switching circuit capable of switching the oscillation frequency by the oscillator of the high frequency power generation source to a state in which the output impedance of the high frequency power generation source is variably controlled to a load impedance and a state in which the oscillation frequency is fixed to a set frequency is attached. The remote plasma cleaning apparatus for a deposition chamber according to claim 1 or 2.

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