JP2014072508A - Plasma processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma processing apparatus in which generation of foreign matters or adhesion of reaction products can be suppressed while optimizing gas supply state.SOLUTION: Faraday shields 18a, 18b and a gas release plate 11 are provided at positions facing each other while holding a dielectric vacuum window 2 therebetween. The gas release plate 11 has an opening (gas release port) for releasing gas into a processing chamber, and the Faraday shields are divided into the Faraday shield 18a disposed in a region facing the opening, and the Faraday shields 18b disposed at other regions. The voltages being applied to respective Faraday shields 18a, 18b can be controlled independently by a matching unit 16.

Description

  The present invention relates to a plasma processing apparatus, and more particularly to an inductively coupled plasma processing apparatus.

  In the semiconductor device industry today, the market for nonvolatile RAM (Random Access Memory) is expanding. Among them, new nonvolatile RAMs such as FeRAM (Ferroelectric Random Access Memory) and MRAM (Magnetic Random Access Memory) are being developed by various companies due to advantages of low power consumption and high-speed operation. These mass productions require etching of non-volatile materials such as PZT (lead zirconate titanate) in FeRAM and CoFe in MRAM. However, in etching these non-volatile materials, reaction products having a low vapor pressure are likely to deposit on the plasma processing chamber inner wall. For this reason, there is a problem in mass production stability, such as frequent occurrence of foreign matters due to deposits being peeled off and adhering to the sample, and changes in the process over time due to changes in the plasma bonding state.

  In the conventional semiconductor device manufacturing field, as an etching or surface treatment technique, an inductively coupled type (in which a processing gas inserted into a processing chamber is turned into plasma by flowing a high-frequency current through an induction coil disposed outside the plasma processing chamber ( Inductively Coupled Plasma) is used. However, in the plasma apparatus, since measures against deposits on the inner wall of the plasma processing chamber when etching a non-volatile material are not sufficient, manual cleaning with air release is repeatedly performed. When the manual cleaning is started, it takes 6 to 12 hours to start the processing of the next sample, so that the operation efficiency of the apparatus is lowered.

  Therefore, a plasma processing apparatus described in Patent Document 1 is used as an inductively coupled plasma processing apparatus. As described in Patent Document 1, a conical dielectric bell jar constituting the upper portion of the processing chamber is installed in the plasma processing chamber, and an induction coil for generating plasma is further installed on the upper portion of the plasma processing chamber. . A conical Faraday shield is installed between the bell jar and the induction coil. By applying a high voltage to the conical Faraday shield, it is possible to control a reaction product adhering to the inner wall of the bell jar. Further, in the gas supply method, the processing gas is supplied through a gas ejection hole installed on the side surface of the plasma processing chamber. The apparatus described in Patent Document 1 realizes plasma processing excellent in mass productivity and etching performance by converting the processing gas into plasma by the induction magnetic field of the induction coil.

  Further, as another inductively coupled plasma processing apparatus, a plasma apparatus described in Patent Document 2 is used. Patent Document 2 has a structure similar to that of Patent Document 1, and a split Faraday shield is installed between a dielectric bell jar and an induction coil for plasma generation. Since each of the divided Faraday shields is independent and voltage control is possible, it is possible to control reaction product adhesion more precisely. The gas supply system has the same structure as that of Patent Document 1, and by using these, a plasma processing apparatus having excellent mass productivity and etching performance is realized.

  Further, as another inductively coupled plasma apparatus, a plasma apparatus described in Patent Document 3 is used. As described in Patent Document 3, a parallel plate dielectric window constituting an upper portion of the processing chamber is installed in the plasma processing chamber, and an induction coil for generating plasma is further installed on the upper portion of the plasma processing chamber. . A parallel plate Faraday shield is installed between the window and the induction coil, and by applying a high voltage to the Faraday shield, a reaction product adhering to the inner wall of the window can be controlled. In the gas supply method, a plurality of radial gas flow paths are provided in the window, and the gas flow paths are manufactured so as to merge at the center of the window. As a result, the supplied processing gases merge at the center of the window and are supplied from the shower hole into the plasma processing chamber. Furthermore, the gas flow path is manufactured with a width equal to or less than the mean free path of the supplied gas, thereby enabling suppression of abnormal discharge in the gas flow path. The apparatus described in Patent Document 3 realizes a plasma processing apparatus excellent in mass productivity and etching performance by the above structure.

JP 2004-235545 A JP 2011-253916 A JP 2011-187902 A

  In recent years, in the field of semiconductor device manufacturing, with the increase in diameter and performance of wafers and displays that are objects to be processed, in plasma processing equipment, the uniformity of plasma generated during sample processing and the stability of mass production are stable. The demand for sex is increasing. In particular, as the diameter of the sample increases, the generated plasma also needs to have a corresponding increased diameter, so that a more uniform and higher density plasma must be generated. For this reason, in order to process the sample uniformly, it is important to supply the processing gas while controlling the sample surface. This is because the process gas supplied dissociates and ionizes, the spatial distribution of the plasma distribution is determined, and the process gas is excited in the plasma to become a reactive radical, which directly affects the distribution of plasma processing characteristics. It is. In addition, the flow distribution of the processing gas affects the exhaust of reaction products that inhibit the processing as well as the transport of reactive radicals used for the processing.

  Also, depending on the processing gas supply location, the capacitive coupling state between the Faraday shield, which serves as a cleaning electrode, and the plasma changes within the processing chamber top plate, and the amount of reaction products adhering to the top plate changes within the surface. There is a problem that a uniform cleaning action cannot be given.

  In the plasma processing apparatuses described in Patent Documents 1 and 2, since the processing gas is supplied by the gas ejection holes installed on the side surface of the plasma processing chamber, most of the processing gas is exhausted as it is. For this reason, there is a problem that the gas concentration on the sample is dilute with respect to the supply amount of the processing gas, and the etching performance such as the etching rate and uniformity is lowered. Further, the relationship between the supply position of the processing gas and the capacitive coupling state is not considered.

  In the inductively coupled plasma processing apparatus described in Patent Document 3, the problems described in Patent Documents 1 and 2 are solved by supplying the processing gas from the center of the window. However, the gas flow path must be processed directly into a dielectric window, and the gas flow path width must be 1 mm or less in order to suppress abnormal discharge in the gas flow path. Since it is not easy to actually process these with high accuracy and the processing cost is very expensive, it is difficult to say that this is a realistic method in an apparatus intended for mass production. Furthermore, only the abnormal discharge suppression technique in Patent Document 3 does not have a sufficient amount of electric field reduction in the gas flow path, and thus abnormal discharge may occur. Further, the relationship between the supply position of the processing gas and capacitive coupling is not considered.

  In view of the above-described problems, one of the objects of the present invention is to provide a plasma processing apparatus capable of suppressing generation of foreign matters or adhesion of reaction products while optimizing a gas supply state. There is. The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of a typical embodiment will be briefly described as follows.

  The plasma processing apparatus according to the present embodiment includes a processing chamber, a dielectric window, an induction coil, a Faraday shield, a high frequency power supply, a matching unit, a gas supply unit, and a gas discharge plate. The processing chamber performs plasma processing on the sample, and the dielectric window seals the upper portion of the processing chamber in a vacuum. The induction coil is disposed above the dielectric window, and the Faraday shield is installed between the dielectric window and the induction coil. The high frequency power supply supplies high frequency power to both the induction coil and the Faraday shield, and the matching unit suppresses the reflected power of the high frequency power. The gas supply means supplies gas into the processing chamber, and the gas discharge plate is provided at a position facing the Faraday shield with the dielectric window interposed therebetween, and discharges the gas supplied from the gas supply means into the processing chamber. Here, the gas discharge plate has an opening for discharging the gas supplied from the gas supply means into the processing chamber, and the Faraday shield has a first region facing the opening and a first region. It is divided into a second region which is a region other than. The matching unit has control means that can independently control the high-frequency voltages applied to the first region and the second region.

  Of the inventions disclosed in this application, the effects obtained by typical embodiments will be briefly described. It is possible to suppress the generation of foreign substances or the attachment of reaction products while optimizing the gas supply state. become.

It is the schematic which shows the structural example of the plasma processing apparatus by Example 1 of this invention. It is a figure which shows the detailed structural example of the periphery of the divided Faraday shield in the plasma processing apparatus of FIG. In the plasma processing apparatus used as the comparative example of FIG. 1, it is the figure which showed typically the actual voltage distribution produced | generated on the lower surface of a gas discharge | release board by a typical Faraday shield. In the plasma processing apparatus of FIG. 1, it is the figure which showed typically the real voltage distribution produced | generated by the Faraday shield on the lower surface of a gas discharge | release board. In the plasma processing apparatus by Example 2 of this invention, it is the schematic which shows the structural example of the principal part, and the figure which showed typically the actual voltage distribution produced | generated by the Faraday shield on the lower surface of a gas emission plate. is there. In the plasma processing apparatus by Example 3 of this invention, it is the schematic which shows the structural example of the principal part, and the figure which showed typically the actual voltage distribution produced | generated by the Faraday shield on the lower surface of a gas emission plate. is there. (A) And (b) is a figure which shows an example of the result of having analyzed the electric field distribution of the Faraday shield in the present Example 1. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for explaining the embodiments, the same reference numerals are given to the same members in principle, and the repeated explanation thereof is omitted.

  FIG. 1 is a schematic diagram illustrating a configuration example of a plasma processing apparatus according to a first embodiment of the present invention. The plasma processing chamber (hereinafter, abbreviated as processing chamber) includes a chamber 1 whose side wall is subjected to surface treatment, for example, an aluminum base material, and a dielectric vacuum window 2 which is a flat dielectric window installed above the chamber 1. Composed. The dielectric vacuum window 2 is made of, for example, quartz and is a member for sealing the upper portion of the processing chamber to a vacuum. An induction coil 17 is disposed above the dielectric vacuum window 2, and Faraday shields 18 a and 18 b are disposed between the dielectric vacuum window 2 and the induction coil 17. A sample stage 4 for placing a sample 3 such as a semiconductor substrate is installed below the processing chamber. By applying a high frequency of several tens of MHz or less from the high frequency power source 6 to the sample 3 via the matching unit 5, the ion energy from the plasma 7 incident on the sample 3 is controlled. In this embodiment, the sample 3 is a 300 mm diameter wafer for semiconductor devices, for example, and the high frequency power source 6 uses a frequency 800 KHz power source.

The chamber 1 is provided with an exhaust port 8. An exhaust device 9 is provided at the tip of the exhaust port 8, and thereby, the pressure in the processing chamber is controlled to be a set pressure within a range of 0.1 Pa to several tens of Pa. A gas used for plasma processing is introduced from a gas supply pipe 10 provided in the chamber 1 of the processing chamber, passes through a gas flow path 12 between the dielectric vacuum window 2 and the gas discharge plate 11, and is located at the center of the gas discharge plate 11. The sample gas 13 is discharged upward as a processing gas 13 from a circular opening provided in the section. The gas discharge plate 11 is made of, for example, quartz. In addition, a large number of high dielectrics 14 serving as high dielectric constant members are installed between the dielectric vacuum window 2 and the gas discharge plate 11 in an island shape, and the gas flow paths 12 are formed by gaps between the high dielectrics 14. It is made. At this time, a member (for example, made of aluminum oxide (Al ₂ O ₃ )) having a higher dielectric constant than the dielectric vacuum window 2 and the gas discharge plate 11 (for example, made of quartz) is used as the high dielectric 14. In this case, the high dielectric 14 absorbs the electric field generated by the induction coil 17 or the Faraday shields 18a and 18b, so that the electric field in the gas channel 12 can be reduced and generated in the gas channel 12. Abnormal discharge can be suppressed.

  The electromagnetic field for generating the plasma 7 is radiated into the processing chamber by applying the output of the high frequency power supply 15 having a frequency of 13.56 MHz to the coiled induction coil 17 through the matching unit 16. When the output of the high frequency power supply 15 is several kW, the inductance of the induction coil 17 is several μH and the high frequency current is several tens of amperes, so the voltage between the terminals of the induction coil 17 is several kW. In order to prevent the high voltage of the induction coil 17 from being directly applied to the plasma 7, divided Faraday shields 18 a and 18 b are installed between the induction coil 17 and the plasma 7.

  The induction coil 17 and the Faraday shields 18a and 18b are connected in series with a high-frequency power source 15 serving as a high-frequency power supply source via a matching unit 16. In the matching unit 16, in order to suppress the reflected power from the induction coil 17 and the reflected power from the Faraday shields 18a and 18b (that is, to perform impedance matching), the variable capacitors VC1 and VC2 whose impedance magnitudes can be variably set. Is connected. A variable capacitor VC4 for controlling the high frequency current supplied to the induction coil 17 is connected. Further, a circuit (variable capacitors VC3, VC5, coils L2, L3) capable of variably setting the magnitude of impedance is connected in parallel with the Faraday shields 18a, 18b. The magnitude of the high frequency power (high frequency voltage) applied to the Faraday shield 18a is controlled by the serial LC circuit of VC3 and L3, and the magnitude of the high frequency power (high frequency voltage) applied to the Faraday shield 18b by the serial LC circuit of VC5 and L2. Is controlled.

  By dividing the Faraday shield in this way and independently controlling the high-frequency voltage applied to each, the ion sputtering rate toward the inner surface of the dielectric vacuum window 2 is controlled for each Faraday shield placement region, and the dielectric vacuum Control (removal) of reaction products adhering to the inner surface of the window 2 can be carried out accurately and over a wide range. Further, capacitors C4 and C5 are connected to the Faraday shields 18a and 18b, respectively. As a result, the impedance of the high frequency power applied to the Faraday shields 18a and 18b can be made zero, and the phase of the high frequency power can be inverted at the resonance point.

  FIG. 2 is a diagram showing a detailed structure example around the divided Faraday shield in the plasma processing apparatus of FIG. The Faraday shields 18a and 18b and the induction coil 17, the dielectric vacuum window 2, the gas discharge plate 11, the high dielectric 14 and the gas flow path 12 shown in FIG. 1 are arranged as shown in FIG. 2, for example. In the example of FIG. 2, the dielectric vacuum window 2 has a circular flat plate shape (disc shape), and the gas release plate 11 has a circular flat plate shape (thick ring shape) with a hollow center. have.

  Here, the outer periphery of the Faraday shield 18a has the same dimensions as the outer periphery of the opening provided in the gas discharge plate 11 in order to supply (discharge) the processing gas to the processing chamber. Moreover, A shown in the drawing indicates the dimension of the gap between the Faraday shields 18a and 18b. Generally, the electric field distribution generated from the Faraday shield draws contour lines and reaches the processing chamber. At this time, if the dimension of the gap A is too short, the electric fields generated by the Faraday shields 18a and 18b may interfere with each other, and the voltage of each Faraday shield may not be controlled. For this reason, the gap A needs to have a sufficient gap so that the electric fields do not interfere with each other. In this embodiment, the dimension of the gap A is set to 4 mm with reference to the analysis results described later.

  FIG. 3 is a diagram schematically showing an actual voltage distribution generated on the lower surface of the gas discharge plate 11 by a typical Faraday shield 19 in the plasma processing apparatus as a comparative example of FIG. In the plasma processing apparatus of the first embodiment, as described above, a large number of high dielectrics 14 are installed between the dielectric vacuum window 2 and the gas discharge plate 11. Therefore, as shown in FIG. 3, when one Faraday shield 19 is provided on the dielectric vacuum window 2, a high dielectric that is other than the opening (gas discharge port) 30 on the lower surface of the gas discharge plate 11. The electric field generated immediately below the region having 14 is smaller than the electric field generated immediately below the region of the opening (gas discharge port) 30. As a result, a non-uniform electric field distribution is generated on the lower surface of the gas discharge plate 11 as shown in FIG.

  FIG. 4 is a diagram schematically showing an actual voltage distribution generated on the lower surface of the gas discharge plate 11 by the Faraday shields 18a and 18b in the plasma processing apparatus of FIG. As in FIG. 3, since the electric field is absorbed by the high dielectric 14, the effective voltage value decreases immediately below the region having the high dielectric 14 other than the opening (gas discharge port) 30. However, in the Faraday shields 18a and 18b of the first embodiment, it is possible to independently control the voltage, so that the voltage value applied to the Faraday shield 18a is reduced or the voltage value applied to the Faraday shield 18b. As a result, the actual voltage distribution on the lower surface of the gas discharge plate 11 can be made uniform as shown in FIG.

  Thereby, on the lower surface of the gas discharge plate 11, the plasma sheath voltage between the region of the opening (gas discharge port) 30 and the plasma 7, and the region between the region other than the opening (gas discharge port) 30 and the plasma 7. The plasma sheath voltage is substantially uniform. As a result, the distribution of the sheath voltage generated on the lower surface of the gas discharge plate 11 even if the processing gas supply port is provided in the arrangement range of the electrodes (in this case, the Faraday shields 18a and 18b) that cause a cleaning action on the processing chamber wall surface. Can be optimized, and the generation of foreign matters or the adhesion of reaction products can be suppressed.

  FIGS. 7A and 7B are diagrams illustrating an example of a result of electric field analysis using simulation to confirm the electric field distribution of the Faraday shield in the first embodiment. The simulation analysis is performed under the condition that the Faraday shields 18a and 18b made of aluminum having a thickness of 2 mm are placed on the dielectric vacuum window 2 made of quartz having a thickness of 15 mm (relative dielectric constant 3.5). Further, an air layer 24 (24a, 24b) (relative dielectric constant 1) is provided between the Faraday shields 18a and 18b, and a voltage of 1000 V is applied to the Faraday shield 18a and 500 V is applied to the Faraday shield 18b. .

  As shown in FIG. 7A, when the air layer 24a is 0.4 mm, it can be seen that the electric field distribution applied from the Faraday shield 18a reaches the Faraday shield 18b and interferes therewith. Since the voltage control of the Faraday shield of the plasma processing apparatus according to the first embodiment is monitored by a circuit mounted in the matching unit 16 and is controlled using the value, the influence of the voltage generated from other Faraday shields is affected. If it is received, malfunction may occur in voltage control. For this reason, when installing the Faraday shields 18a and 18b, it is better to provide a sufficient gap so as not to interfere with each other's electric field. However, if the gap is excessively large, the electric field distribution in the gap is lowered, and the plasma 7 generated on the lower surface of the gas discharge plate 11 becomes non-uniform or adheres directly below the gap. In order to reduce the effect of removing reaction products, it is preferable to optimize the size of the gap in the gap by using electric field analysis as in the first embodiment.

  FIG. 7B shows the electric field distribution when the air layer 24b is 4 mm. As shown in FIG. 7B, it can be seen that the electric field of the Faraday shield 18a does not reach the Faraday shield 18b by providing a sufficient gap between the Faraday shield 18a and the Faraday shield 18b. In Example 1, the dimension of the gap A in FIG. 2 is set to 4 mm from the result of performing the electric field analysis several times as described above.

  As described above, the plasma processing apparatus according to the first embodiment includes the Faraday shields 18a and 18b and the gas discharge plate 11 at positions facing each other across the dielectric vacuum window 2. The gas discharge plate 11 includes an opening (gas discharge port) 30 for discharging (supplying) gas to the processing chamber, and the Faraday shield includes a Faraday shield 18a disposed in a region facing the opening, and the others. And the Faraday shield 18b disposed in the region. Further, the voltages applied to the Faraday shields 18a and 18b can be controlled independently. With such a configuration, the plasma sheath voltage in the region of the opening (gas discharge port) 30 and the plasma sheath voltage in the other region can be independently controlled. It is possible to optimize the distribution of the sheath voltage generated in the processing chamber wall surface while providing a degree of freedom. That is, it is possible to suppress the generation of foreign matters or the adhesion of reaction products while optimizing the gas supply state.

  In the first embodiment, the opening (gas discharge port) 30 is arranged at the center of the gas discharge plate 11. Thereby, the situation where most of the gas is exhausted as it is can be suppressed, and the etching performance such as etching rate and uniformity can be improved. Further, here, a plurality of high dielectrics 14 are provided between the dielectric vacuum window 2 and the gas discharge plate 11. As a result, even when the electromagnetic field intensity is strong as in the inductively coupled plasma processing apparatus, it is possible to generate uniform plasma on the sample without causing abnormal discharge. As a result, a plasma processing apparatus having high etching performance and mass production stability can be realized.

  FIG. 5 is a schematic view showing a configuration example of the main part of the plasma processing apparatus according to the second embodiment of the present invention, and schematically shows the actual voltage distribution generated on the lower surface of the gas discharge plate by the Faraday shield. FIG. In FIG. 5, the same reference numerals as those in FIG. FIG. 5 is different from FIG. 3 in that a gas discharge plate 22 having a ring-shaped opening (gas discharge port) 31 is provided, and a Faraday divided according to the shape of the opening (gas discharge port) 31. It is a point provided with shields 20a and 20b. At this time, the ring-shaped opening (gas discharge port) 31 is provided at an intermediate portion between the center and the outer periphery of the gas discharge plate 22, and accordingly, the Faraday shield 20 b is connected to the dielectric vacuum window 2. It is arranged in a ring-shaped region facing the opening (gas discharge port) 31 with a gap therebetween.

  The processing gas passes through the gaps between the high dielectrics 14 between the dielectric vacuum window 2 and the gas discharge plate 22, and from a ring-shaped opening (gas discharge port) 31 provided at an intermediate portion of the gas discharge plate 22. Released. At this time, the divided Faraday shields 20a and 20b can be independently voltage controlled using the same means as in the first embodiment. As a result, in the conventional Faraday shield, the effective voltage becomes non-uniform as shown in FIG. 3, but by using the Faradales 20a and 20b of the second embodiment, a uniform voltage distribution as shown in FIG. Can be obtained.

  As described above, according to the second embodiment, the same effect as in the first embodiment can be obtained, and the diameter of the ring-shaped opening (gas discharge port) 31 is arbitrarily set. As a result, it is possible to construct a process gas supply path that is optimal for a predetermined plasma process. Thereby, the plasma processing can be made uniform.

  FIG. 6 is a schematic diagram showing a configuration example of the main part of the plasma processing apparatus according to the third embodiment of the present invention, and schematically shows the actual voltage distribution generated on the lower surface of the gas discharge plate by the Faraday shield. FIG. In FIG. 6, the same reference numerals as those in FIG. 3 denote the same members, and a description thereof will be omitted. FIG. 6 differs from FIG. 3 in that a gas discharge plate 23 having a ring-shaped opening (gas discharge port) 32 is provided, and a Faraday divided according to the shape of the opening (gas discharge port) 32. It is a point provided with shields 21a and 21b. At this time, the ring-shaped opening (gas discharge port) 32 is provided on the outer peripheral portion of the gas discharge plate 23, and accordingly, the Faraday shield 21 b is sandwiched between the dielectric vacuum window 2 and the opening ( It is arranged in a ring-shaped region facing the gas discharge port 32.

  The processing gas passes through the gaps between the high dielectrics 14 between the dielectric vacuum window 2 and the gas discharge plate 23, and from a ring-shaped opening (gas discharge port) 32 provided on the outer periphery of the gas discharge plate 23. Released. At this time, the divided Faraday shields 21a and 21b can be independently voltage controlled using the same means as in the first embodiment. As a result, in the conventional Faraday shield, the effective voltage becomes nonuniform as shown in FIG. 3, but by using the Faradales 21a and 21b of the third embodiment, a uniform voltage distribution as shown in FIG. Can be obtained.

  As described above, according to the third embodiment, the same effect as in the first embodiment can be obtained, and the diameter of the ring-shaped opening (gas discharge port) 32 is arbitrarily set. As a result, it is possible to construct a process gas supply path that is optimal for a predetermined plasma process. Thereby, the plasma processing can be made uniform.

  In addition, this invention is not limited to these Examples mentioned above, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Also, a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of a certain embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  For example, here, the gas discharge plate 11 having one disc-shaped opening 30 in the center and the gas discharge having one ring-shaped opening 31 (or 32) in the middle (or outer periphery). A plate 31 (or 32) is shown. By combining these appropriately, for example, the gas discharge plate may have two ring-shaped openings, or one disk-shaped opening and one ring-shaped opening. Can be changed as appropriate. Here, the plurality of high dielectrics 14 are arranged in an island shape on the gas discharge plate, but the shape and size of each of the high dielectrics 14 can be appropriately determined as necessary.

DESCRIPTION OF SYMBOLS 1 Chamber 2 Dielectric vacuum window 3 Sample 4 Sample stand 5,16 Matching device 6,15 High frequency power supply 7 Plasma 8 Exhaust port 9 Exhaust device 10 Gas supply pipe 11, 22, 23 Gas discharge plate 12 Gas flow path 13 Process gas 14 High dielectric 17 induction coil 18a, 18b, 19, 20a, 20b, 21a, 21b Faraday shield 24a, 24b Air layer 30, 31, 32 Opening (gas discharge port)
L Coil VC Variable capacitor C Capacitor

Claims (5)

A processing chamber for performing plasma processing on the sample;
A flat dielectric window that seals the upper portion of the processing chamber to a vacuum;
An induction coil disposed above the dielectric window;
A Faraday shield installed between the dielectric window and the induction coil;
A high frequency power supply for supplying high frequency power to both the induction coil and the Faraday shield;
A matching unit for suppressing the reflected power of the high-frequency power;
Gas supply means for supplying gas into the processing chamber;
A sample stage provided in the processing chamber for mounting the sample;
A gas release plate that discharges gas supplied from the gas supply means into the processing chamber and is provided at a position facing the Faraday shield across the dielectric window;
The gas discharge plate has an opening for discharging the gas supplied from the gas supply means into the processing chamber,
The Faraday shield is divided into a first region facing the opening and a second region which is a region other than the first region,
The said matching device is a plasma processing apparatus which has a control means which can control each high frequency voltage applied to said 1st area | region and said 2nd area | region independently. The plasma processing apparatus according to claim 1,
The control means includes
First control means for controlling a high-frequency voltage applied to the first region;
Second control means for controlling the high-frequency voltage applied to the second region,
The first control means and the second control means each have a series LC circuit,
Each of the series LC circuits is a plasma processing apparatus having a variable capacitor. The plasma processing apparatus according to claim 2, wherein
The first region is circular;
The said opening part is a plasma processing apparatus arrange | positioned in the center part of the said gas discharge | release board. The plasma processing apparatus according to claim 3, further comprising:
The plasma processing apparatus which has several 1st member used as a dielectric between the area | regions other than the said opening part of the said gas emission plate, and the said dielectric material window. The plasma processing apparatus according to claim 4, wherein
The gas release plate is a dielectric;
The plasma processing apparatus, wherein a relative dielectric constant of the first member is higher than a relative dielectric constant of the dielectric window and the gas discharge plate.