JP6526568B2 - Parts for plasma apparatus and method for manufacturing the same - Google Patents

Description

  The present invention relates to an oxide film-coated plasma device component which is excellent in corrosion resistance to a halogen-based corrosive gas and plasma and can be suitably used for a plasma device component for semiconductor / liquid crystal production or the like.

  Among semiconductor manufacturing equipment, parts for equipment in the etching process, the CVD film formation process, and the ashing process for removing the resist, in which the plasma process is mainstream, are exposed to halogen-based corrosive gases such as highly reactive fluorine and chlorine. .

  Therefore, ceramic materials such as alumina (aluminum oxide), aluminum nitride, yttria (yttrium oxide) and YAG are widely used as constituent materials of parts exposed to halogen plasma in the above-described steps.

  For example, in Patent Document 1, the base material is made of a metal or a ceramic provided with a metal electrode, and the outermost surface on the base material is 5% by weight or more and less than 60% by weight of tungsten or molybdenum based on yttrium oxide. It is described that parts for plasma apparatus (electrostatic chuck) having a stable low volume resistivity dielectric layer can be obtained by dispersing and forming a yttrium oxide based plasma spray coating having a porosity of 5% or less. ing.

  Further, in Patent Document 2, a dielectric layer composed of aluminum oxide as a main component and a resistivity adjusting component containing titanium oxide and a group 5A metal is formed on the surface of a ceramic substrate such as aluminum oxide by air plasma spraying. It is described that by doing so, a component for plasma apparatus (electrostatic chuck) having a stable low volume resistivity dielectric layer is obtained.

JP, 2011-60826, A Unexamined-Japanese-Patent No. 2003-282693

  However, since the coating such as yttrium oxide or aluminum oxide formed by the thermal spraying method is formed by depositing the raw material powder such as yttrium oxide or aluminum oxide in the molten state, the molten particles are rapidly solidified by the thermal spraying heat source At the time of adhesion, a large number of micro cracks are generated in the particles deposited in a flat state, and further, a strain generated by rapid cooling and solidification remains in each flat particle, and a film is formed. When active radicals generated by plasma discharge are irradiated to a film such as yttrium oxide or aluminum oxide in such a state, the active radicals attack the microcracks to propagate the cracks and further release the internal strain. Further, there is a problem that the crack propagates and the thermal spray coating is broken to cause generation of particles.

  In addition, since parts for plasma apparatus having a ceramic spray-coated film have a structure in which flat particles are deposited, irregular irregularities remain on the surface even when polishing and the like are performed, and dielectrics are generated during processing such as etching. The particles present on the surface of the layer fall off, and there is a concern about the generation of particles resulting from these.

  As described above, since a coating such as yttrium oxide or aluminum oxide formed by thermal spraying is a deposited film in a molten state, it tends to be a source of generation of particles and causes a decrease in product yield. Formation is prone to problems.

  Furthermore, in the case of forming a thermal spray coating on a component, in order to deposit a thermal spray coating on the surface previously subjected to a blasting treatment that sprays abrasive grains and the like on the substrate surface together with high pressure particles, Remaining pieces of the blast material (abrasive) may be present, or a fragile fractured layer may be formed on the surface of the part by blasting. As described above, since the thermal spray coating is deposited on the surface of the component, a stress acts on the interface between the component and the thermal spray coating due to the thermal stress generated by the temperature change due to the plasma discharge, and the thermal spray coating easily causes film peeling. . In particular, when the pressure for blasting and the abrasive grain size are increased, the occurrence of film peeling becomes remarkable. Therefore, the life of the thermal spray coating is a factor which is greatly influenced by the conditions of the blast treatment in addition to the configuration of the thermal spray coating itself.

  As described above, since there are defects in the yttrium oxide coating formed by the thermal spraying method and at the interface with the parts, even a yttrium oxide coating having plasma resistance and corrosion resistance can be extended in life of the coating formed by the thermal spraying method There is a big problem from

  Further, in the case of plasma spraying, the particle diameter of the yttrium oxide powder supplied as a raw material is as large as about 10 to 45 μm, so pores (voids) of up to about 15% occur in the formed sprayed coating and The roughness is coarsened to about 6 to 10 μm on the basis of the arithmetic average roughness Ra, and there is a problem that it takes a long time to planarize by polishing treatment. When using such an electrostatic chuck on which a thermal spray coating has been formed, plasma etching proceeds through the pores. Furthermore, when the surface roughness is large, the plasma discharge is struck on the convex portion of the sprayed surface in a concentrated manner. Thus, in addition to the concentration of plasma attack on internal defects, the thermal spray coating becomes brittle due to surface defects, so the amount of particles generated due to the wear of the thermal spray coating increases and the service life of parts for plasma apparatus decreases. There was also a problem that

  That is, in parts for plasma apparatus where both plasma resistance and corrosion resistance are required, particles are easily generated even in the yttrium oxide film formed by the thermal spraying method, and film replacement defects occur. The increase leads to a decrease in productivity and an increase in etching cost.

  In recent semiconductor devices, narrowing (for example, 24 nm, 19 nm) of the line width has progressed in order to achieve a particularly high degree of integration. In such a narrowed wiring and an element having the same, for example, even if very fine particles (fine particles) having a diameter of about 40 nm are mixed, causes of wiring defects (breaks), element defects (shorts), etc. Therefore, it is strongly required to more strictly suppress the generation of fine particles resulting from the device components.

  The present invention has been made to solve the above-described conventional problems, and improves plasma resistance and corrosion resistance of the coating film itself during the etching step to stably and effectively suppress the generation of particles, and can be used for apparatus cleaning and parts. It is possible to prevent film peeling and effectively suppress the generation of fine particles and to prevent contamination by impurities, while suppressing the decrease in productivity and the increase in etching and film formation costs associated with replacement and the like. It is an object of the present invention to provide a component for a plasma device, a component for a plasma device that does not cause damage such as corrosion or deformation to a member by chemical treatment or blast treatment in regeneration treatment, and a method of manufacturing the same.

In the plasma device component having the yttrium oxide film formed by the impact sintering method of the present invention, the substrate is made of metal or ceramic, and the outermost surface on this substrate has a film thickness of 10 to 200 μm, While the film density is 90% or more and the area ratio of particles in which grain boundaries can be confirmed in a unit area of 20 μm × 20 μm is 5 to 80%, the area ratio of particles in which grain boundaries can not be confirmed is 20 to 95% An yttrium oxide film containing an oxide of a lanthanoid element, and the yttrium oxide film is at least one selected from lanthanoid elements consisting of La, Ce, Sm, Dy, Gd, Er, and Yb. the containing 1-8 wt% in terms of oxide, upon XRD analysis of the yttrium oxide coating containing an oxide of the lanthanoid elements, pairs strongest peak Ic cubic Yttrium oxide having a ratio (Im / Ic) of the strongest peak Im of monoclinic crystals of 0.2 to 0.6, an average particle diameter of the oxide particle of the lanthanoid element and an oxide of the lanthanoid element It is characterized in that the average particle diameter of the particles is 0.05 to 5 μm .

  The yttrium oxide film containing an oxide of a lanthanoid element preferably has a thickness of 10 to 200 μm, and a density of the film of 99% to 100%. The above-mentioned oxide particles of yttrium oxide and lanthanoid elements contain fine particles having a particle diameter of 1 μm or less, and the yttrium oxide particles capable of confirming the grain boundaries preferably have an average particle diameter of 2 μm or less. In addition, it is preferable that the average particle diameter of the whole of the oxide particle of a yttrium oxide and a lanthanoid type element is 5 micrometers or less.

  In addition, when the yttrium oxide film containing an oxide of the lanthanoid element is subjected to XRD analysis, the ratio (Im / Ic) of the strongest peak Im of monoclinic crystal to the strongest peak Ic of cubic crystal is 0.2 to 0.6. Is preferred. Furthermore, it is preferable that the yttrium oxide film containing an oxide of the lanthanoid element have a surface roughness Ra of 0.5 μm or less by polishing treatment.

  A method of manufacturing a component for a plasma device having an yttrium oxide film containing an oxide of a lanthanoid element formed by the impact sintering method of the present invention comprises: supplying a slurry containing oxide particles to a combustion flame; And a step of spraying oxide particles of a lanthanoid element at a spraying speed of 400 to 1000 m / sec onto the base material.

  Here, the average particle diameter of the yttrium oxide particles and the oxide particles of the lanthanoid element is preferably 0.05 to 5 μm. The film thickness of the yttrium oxide film containing an oxide of a lanthanoid element is preferably 10 μm or more. It is preferable to supply a slurry containing yttrium oxide particles and oxide particles of lanthanoid elements to the center of the combustion flame.

  As in the present invention, an oxide of a lanthanum-based element using impact sintering, which is deposited without melting a supplied powder containing fine particles having an average particle size of 5 μm or less and a particle size of 1 μm or less at the time of film formation. According to the yttrium oxide film containing the above, it is difficult to form flat molten particles and to deposit fine particles having a particle size of 1 μm or less, thereby reducing microvoids and reducing surface defects.

  Yttrium oxide coatings containing oxides of lanthanide series elements such as La, Ce, Sm, Dy, Gd, Er, and Yb in the coating achieve higher density and surface smoothing than coatings with yttrium oxide alone As a result, internal defects in the coating can be reduced. As a result, the densification of the film is improved and the stability of the crystal structure of the oxide constituting the film is enhanced as compared with the film composed of yttrium oxide alone, so that the chemical stability of the film can be improved. It is possible to improve plasma resistance and corrosion resistance.

The above-mentioned lanthanoid element can be suitably used in any of a simple metal, an oxide, and a composite oxide with Y ₂ O ₃ . Preferably, it is an oxide or a composite oxide. An oxide or a composite oxide can further improve the corrosion resistance.

  By applying such an oxide film to a plasma device component utilizing plasma discharge, the plasma resistance of the component can be improved, and the amount of particle generation and the amount of impurity contamination can be suppressed. The number of times of device cleaning and parts replacement can be significantly reduced because the members are not damaged by corrosion, deformation or the like in the chemical treatment or the blast treatment in the regeneration treatment. The reduction of the particle generation amount greatly contributes to the improvement of the yield of various thin films to be subjected to plasma etching, and elements and parts using the thin films. In addition, the reduction of the number of times of device cleaning and part replacement greatly contributes to the improvement of the productivity and the reduction of the etching cost and the film forming cost.

  According to the present invention, the generation of fine particles generated from parts is stably and effectively suppressed, and the reduction in productivity and the increase in parts cost accompanying frequent device cleaning, parts replacement, etc. are suppressed. A component for a plasma device, which is applicable to the manufacture of highly integrated semiconductor devices, and can also reduce the cost of etching and film formation by improving the operation rate, and a method of manufacturing the same. be able to.

FIG. 1 is a cross-sectional view schematically illustrating a cross-sectional structure of a plasma device component of the present invention. FIG. 5 is a microscopic view showing an example of a yttrium oxide film containing a lanthanoid oxide.

  Hereinafter, modes for carrying out the present invention will be described.

  The component for a plasma device having an yttrium oxide film formed by the impact sintering method of the present invention is a lanthanoid selected from La, Ce, Sm, Dy, Gd, Er, Yb and 1 to 8% by mass on the yttrium oxide film. A film containing an oxide of a base element, having a film thickness of 10 μm or more, a film density of 90% or more, and particles in which grain boundaries present in a film unit area of 20 μm × 20 μm can be confirmed The area ratio of is 0 to 80%, while the area ratio of particles in which grain boundaries can not be confirmed is 20 to 100%.

  FIG. 1 shows an example of the configuration of an electrostatic chuck component as a component for a plasma apparatus according to the present invention. In the figure, reference numeral 1 is a component for a plasma apparatus, 2 is a yttrium oxide film containing an oxide of a lanthanoid element, and 3 is a substrate.

  Yttrium oxide alone has strong resistance to chlorine-based plasma attack, fluorine-based plasma attack, and radical attack (for example, active F radical and Cl radical), but has corrosion resistance La, Ce, Sm, Dy, Gd, Er, When an oxide of a lanthanoid element selected from Yb is contained in yttrium oxide in a proportion of 1 to 8% by mass, the corrosion resistance can be further improved.

  These lanthanoid-based oxide particles bind yttrium oxide particles to improve the strength at the grain boundary, exhibit an effect of eliminating the particle level difference in polishing finish and the like, and it becomes possible to adjust the volume resistivity of the film. When the addition amount of the oxide of the lanthanoid element is less than 1% by mass, the above effect is not sufficiently exhibited. On the other hand, when the addition amount exceeds 8% by mass, the grain boundary layer becomes thick, which leads to a decrease in the film strength, and the particle level difference becomes remarkable. A more preferable addition amount is 2 to 6% by mass.

  The yttrium oxide film containing an oxide of a lanthanoid element has yttrium oxide particles containing an oxide of a lanthanoid element. For example, when a film is formed by a general thermal spraying method, the film is formed in a state in which yttrium oxide particles containing an oxide of a lanthanoid element are dissolved. Therefore, yttrium oxide particles containing an oxide of a lanthanoid element are flat. On the other hand, in the present invention, while the area ratio of particles in which grain boundaries can be identified in a unit area of 20 μm × 20 μm of the coating structure is 0 to 80%, the area ratio of particles in which grain boundaries can not be identified is 20 to 100% It is characterized by being.

  The yttrium oxide particles containing an oxide of a lanthanoid element which can confirm the grain boundaries can be confirmed by a magnified photograph. For example, a scanning electron micrograph is taken at 5000 × magnification.

The figure (enlarged photograph) which shows an example of the yttrium oxide film containing the oxide of a lanthanoid type element in FIG. 2 was shown. In the figure, reference numeral 4 is a particle whose grain boundary can not be confirmed, and 5 is a particle whose grain boundary can be confirmed.

  In the "particles whose grain boundaries can be identified", the grain boundaries of individual particles can be identified by the difference in contrast. On the other hand, in the “particles in which grain boundaries can not be confirmed”, adjacent particles are bonded to each other, and grain boundaries of individual particles can not be confirmed. The unit area of the coated tissue was 20 μm × 20 μm. Also, the unit area is measured at any three points, and the average value is defined as the area ratio of "particles whose grain boundaries can be confirmed" and "particles containing oxides of lanthanoid elements whose grain boundaries can not be confirmed". In FIG. 2, the particle group of "particles whose grain boundaries can be confirmed" and the particle group of "particles whose grain boundaries can not be confirmed" are mixed.

  The impact sintering method is a coating method in which particles are jetted to form a film by a combustion flame, and the particles collide at a high speed, and sinter bond by the heat of crushing of the particles due to the collision to form a film. is there. Therefore, the yttrium oxide particles in the yttrium oxide coating containing the oxide of the lanthanoid element tend to form a coating having a fractured shape more easily than the particle shape of the raw material powder.

  In addition, the yttrium oxide particles containing the oxide of the lanthanoid element are melted by controlling the injection speed of the yttrium oxide particles containing the oxide of the lanthanoid element to a high speed and accelerating the particle velocity to a critical speed or more at which the particle starts to deposit. It is possible to obtain a yttrium oxide film containing an oxide of a lanthanoid-based element with a high film density, which can maintain the particle shape of the raw material powder without forming a film. In the impact sintering method, since high-speed injection is possible, it is easy to obtain a structure in which "particles whose grain boundaries can be confirmed" and "particles whose grain boundaries can not be confirmed" are mixed.

  Assuming that the total of the area ratio of "particles whose grain boundaries can be confirmed" and "particles whose grain boundaries can not be confirmed" is 100%, while the area ratio of "particles whose grain boundaries can be confirmed" is 0 to 80%, It is important that the area ratio of "particles whose grain boundaries can not be confirmed" is 20 to 100%.

  The impact sintering method is a film forming method in which yttrium oxide particles containing an oxide of a lanthanoid element are jetted at high speed, and the particles are deposited by destructive heat when colliding with a substrate. Yttrium oxide particles containing an oxide of a lanthanoid element are thermally bonded during deposition by heat of destruction, whereby yttrium oxide particles containing an oxide of a lanthanoid element whose grain boundaries can not be identified are formed.

  In addition, since the raw material powder is melted and not jetted by performing high-speed injection, deposition can be performed while maintaining the powder shape of yttrium oxide particles containing an oxide of a lanthanoid element as the raw material powder. Therefore, no stress is generated inside the film, and a dense film having a strong bonding force can be formed.

  If the area ratio of "particles whose grain boundaries can be confirmed" exceeds 80%, the heat of destruction due to impact is insufficient, and the deposition is rapidly cooled during deposition, resulting in a decrease in film density and bonding strength, and in some cases Cracks occur. The area ratio of "particles whose grain boundaries can be confirmed" is preferably 0 to 50%. This means that the area ratio of "particles whose grain boundaries can not be confirmed" is preferably in the range of 50 to 100%.

  Further, the thickness of the yttrium oxide film containing an oxide of a lanthanoid element is required to be 10 μm or more. If the film thickness is less than 10 μm, the effect of providing a yttrium oxide film containing an oxide of a lanthanoid element can not be sufficiently obtained, and on the contrary, the film may be a cause of peeling.

  The upper limit of the thickness of the yttrium oxide film containing an oxide of the above-mentioned lanthanoid element is not particularly limited, but even if it is excessively thick, no further effect can be obtained, and it also causes a cost increase. Therefore, the thickness of the yttrium oxide film containing the oxide of the lanthanoid element is in the range of 10 to 200 μm, and the more preferable range is 50 to 150 μm.

  Also, the density of the coating needs to be 90% or more. The density of the film is the opposite term of the porosity, and the density of 90% or more has the same meaning as the porosity of 10% or less.

The film density is measured by taking a 500 × magnified photo of an yttrium oxide film containing an oxide of a lanthanoid element in the film thickness direction with an optical microscope and calculating the area ratio of pores taken there. In particular,
"Film density (%) = 100-area ratio of pores"
The coating density is calculated by the following equation. When calculating the film density, the area of a unit area of 200 μm × 200 μm of tissue is analyzed. In addition, when the thickness of a film is thin, it shall measure in multiple places until the unit area of a sum becomes 200 micrometers x 200 micrometers.

  The film density is preferably 90% or more, more preferably 95% or more, and still more preferably 99% or more and 100% or less.

  When a large number of pores (voids) exist in the yttrium oxide film containing an oxide of a lanthanoid element, erosion such as plasma attack proceeds from the pore and the life of the yttrium oxide film containing an oxide of a lanthanoid element is reduced. . In particular, it is important that the surface of the yttrium oxide film containing the oxide of the lanthanoid element has few pores.

  The surface roughness of the yttrium oxide film containing an oxide of a lanthanoid element is preferably set to a surface roughness of Ra 0.5 μm or less by polishing treatment. When the surface roughness after polishing is not more than 0.5 μm, the wafer is in close contact with the dielectric layer, and the etching uniformity is improved. On the other hand, when the surface roughness after polishing exceeds Ra 0.5 μm, the wafer is deformed and the adhesion is lowered, the etching property is not uniform, and particles are easily generated.

  In addition, the average particle diameter of the yttrium oxide particles containing an oxide of a lanthanoid element which can confirm the grain boundary is 2 μm or less, and the whole lanthanoid element including the yttrium oxide particle containing an oxide of a lanthanum element whose grain boundary can not be confirmed. It is preferable that the average particle diameter of the yttrium oxide particles containing oxides of 5 or less is 5 μm or less.

  It is preferable that the yttrium oxide powder containing the oxide of the lanthanoid type element as a raw material powder which uses an impact-sintering method so that it may mention later has an average particle diameter in the range of 0.05-5 micrometers. When the average particle diameter of the yttrium oxide particles containing the oxide of the lanthanoid element as the raw material powder exceeds 5 μm, the particles are not crushed when they collide, and it becomes difficult to form a film, and further the blast action of the particles themselves As a result, the coating may be damaged and a crack may occur.

  In addition, when the yttrium oxide particles containing an oxide of a lanthanoid element become 5 μm or less, the crushing proceeds appropriately when the fine particles collide, and the heat generation due to the crushing promotes particle bonding to easily form a film. The formed film has a large bonding force between particles, reduces wear by plasma attack and radical attack, reduces particle generation amount, and improves plasma resistance.

  A more preferable value of the particle diameter of the particles is 0.05 μm or more and 3 μm or less, but when it is less than 0.05 μm, the particle crushing becomes difficult to progress, and although it is formed as a film, it becomes a low density film The application range of the particle size of the fine particles is preferably 0.05 to 5 μm because the plasma resistance and the corrosion resistance decrease. However, if the fine particles less than 0.05 μm are less than 5% of the whole yttrium oxide particles containing the oxide of the lanthanoid element, the film formation does not deteriorate, so a powder containing fine particles less than 0.05 μm is used I don't care.

  The average particle diameter is determined using a magnified image as shown in FIG. Grains whose grain boundaries can be identified have the longest diagonal in the individual grains shown in the photograph as the grain size. For particles whose grain boundaries can not be identified, their diameter is taken as the particle size using the hypothetical circle of each particle. This operation is performed for each of 50 particles and 100 particles in total, and the average value thereof is taken as an average particle diameter.

  In addition, when a yttrium oxide film containing an oxide of a lanthanoid element is subjected to XRD analysis (X-ray diffraction analysis), the ratio (Im /) of the strongest peak Im of monoclinic crystal to the strongest peak Ic of cubic crystal (Im / It is preferable that Ic) is 0.2-0.6.

  The said XRD analysis shall be performed by 2 theta method, Cu target, 40 kV of tube voltages, and 40 mA of tube currents. The strongest peak of cubic crystals is detected between 28-30 °, while the strongest peak of monoclinic crystals is detected between 30-33 °. Generally, commercially available yttrium oxide particles are cubic. It is preferable that monoclinic crystals increase because it changes to monoclinic crystals by the fracture heat of the impact sintering method and the plasma resistance improves as the monoclinic crystals increase.

  Next, a method of manufacturing a plasma device component according to the present invention will be described.

  The manufacturing method of a component for a plasma device having an yttrium oxide film containing an oxide of a lanthanoid element formed by the impact sintering method of the present invention comprises: preparing a slurry containing yttrium oxide particles containing an oxide of a lanthanoid element in a combustion flame. And a step of supplying yttrium oxide particles containing an oxide of a lanthanoid element at a jet speed of 400 to 1000 m / sec onto the substrate.

  Moreover, it is preferable that the average particle diameter of the yttrium oxide particle containing the oxide of the said lanthanoid type element is 0.05-5 micrometers. Furthermore, the film thickness of yttrium oxide particles containing an oxide of a lanthanoid element is preferably 10 μm or more. The slurry containing yttrium oxide particles containing an oxide of a lanthanoid element is preferably supplied to the center of the combustion flame.

  The impact sintering method is a film forming method in which a slurry containing yttrium oxide particles containing an oxide of a lanthanoid element is supplied into a combustion flame to rapidly spray yttrium oxide particles containing an oxide of a lanthanoid element. .

  The film forming apparatus for carrying out the impact sintering method includes a combustion source supply port for supplying a combustion source, and a combustion chamber connected thereto. The combustion flame is generated at the combustion flame port by burning the combustion source in the combustion chamber. A slurry supply port is disposed in the vicinity of the combustion flame, and the yttrium oxide particle slurry containing the oxide of the lanthanoid element supplied from the slurry supply port is sprayed from the combustion flame onto the substrate through the nozzle. It will be filmed.

  As the combustion source, oxygen, acetylene, kerosene or the like may be used, and two or more may be used as needed. Furthermore, the combustion conditions such as the blending ratio of the combustion source and the input amount of the cooling gas are adjusted so that the temperature of the combustion flame is less than the boiling point of the yttrium oxide particles containing the oxide of the lanthanoid element to be formed.

  If the temperature of the combustion flame is higher than the boiling point of the raw material particles, the yttrium oxide particles containing the oxide of the lanthanoid element supplied as a slurry may evaporate, decompose or melt even if high-speed injection, and do not deposit Or even if it deposits it will be in the same form as thermal spraying.

  In the case of forming an yttrium oxide film containing an oxide of a lanthanoid element by impact sintering, the ejection velocity of the yttrium oxide particles containing an oxide of the lanthanoid element is in the range of 400 m / sec to 1000 m / sec. preferable. If the jet speed is less than 400 m / sec, the pulverization at the time of collision of the particles may be insufficient and a film having a high film density may not be obtained. In addition, when the injection speed exceeds 1000 m / sec, the collision force becomes excessive, the blasting effect by the yttrium oxide particles containing the oxide of the lanthanoid element tends to be generated, and it is difficult to obtain the target film.

  When an yttrium oxide particle slurry containing an oxide of a lanthanoid element is introduced into the slurry supply port, it is preferable to supply the slurry so that the slurry is injected into the center of the combustion flame.

  When the yttrium oxide particle slurry is supplied to the outside of the combustion flame, the injection speed is not stable. Yttrium oxide particles containing oxides of some lanthanoid elements are injected outside the combustion flame, and some are injected after reaching the center. Even with the same combustion flame, the combustion temperature is slightly different between the outside and the inside. By forming the film under the same temperature condition and the same injection speed as much as possible, it is possible to control the structure composed of "particles whose grain boundaries can be confirmed" and "particles whose grain boundaries can not be confirmed".

  The impact sintering method is a coating method in which particles are jetted to form a film by a combustion flame, and the particles collide at a high speed, and sinter bond by the heat of crushing of the particles due to the collision to form a film. is there. Therefore, the yttrium oxide particles containing the oxide of the lanthanoid element in the film tend to form a film having a fractured shape more easily than the particle shape of the raw material powder.

  In addition, the yttrium oxide particles containing the oxide of the lanthanoid element are not melted by controlling the injection speed of the yttrium oxide particle containing the oxide of the lanthanoid element at high speed and accelerating the particle velocity to a critical speed or more at which the particle starts to deposit. It is possible to obtain an yttrium oxide film containing an oxide of a lanthanum-based element having a high film density. In the impact sintering method, high-speed injection is possible, so it is easy to obtain “particles in which grain boundaries can not be confirmed”. A yttrium oxide film containing an oxide of a lanthanoid element having an area ratio of particles in which grain boundaries can be confirmed as in the present invention is 0 to 80%, while an area ratio of particles in which grain boundaries can not be confirmed is 20 to 100%. Can be obtained efficiently.

  Moreover, it is also effective to adjust the injection distance L from a nozzle to a base material as a control method of the generation ratio of "particles in which grain boundaries can be confirmed" and "particles in which grain boundaries can not be confirmed". As described above, the impact sintering method sprays yttrium oxide particles containing an oxide of a lanthanoid element at a high speed using a combustion flame and deposits by sinter bonding using the heat of fracture of particles at collision. It is a way to

  It is preferable to adjust the injection distance L to 100 to 400 mm in order to form a film without forming the yttrium oxide particles containing the oxide of the lanthanoid-based element, which has been warmed once by the combustion flame, into a molten flat shape. If the injection distance L is less than 100 mm, the distance is too short to obtain a sintered-bonded film without crushing of the yttrium oxide particles containing the oxide of the lanthanoid element. On the other hand, if the injection distance L exceeds 400 mm, the impact force becomes weak because the distance is too large, and it is difficult to obtain an yttrium oxide film containing the target oxide of a lanthanoid element. By controlling the above-described injection speed and the yttrium oxide particle size containing the oxide of the lanthanoid element as the raw material powder, it is possible to control the melted and unmelted structure. Preferably, the injection distance L is 100 to 200 mm.

  The yttrium oxide particle slurry containing an oxide of a lanthanoid element is preferably a slurry containing yttrium oxide particles containing an oxide of a lanthanoid element having an average particle diameter of 0.05 to 5 μm as a raw material powder. The solvent for slurrying is preferably a relatively volatile solvent such as methyl alcohol or ethyl alcohol.

  The yttrium oxide particles containing an oxide of a lanthanoid element are preferably sufficiently pulverized to be free from coarse particles and then mixed with a solvent. For example, when there are coarse particles having a particle size of 20 μm or more, it becomes difficult to obtain a uniform film. Moreover, as for the yttrium oxide particle | grains in a slurry, 30-80 vol% is preferable. If the slurry has appropriate fluidity, the supply to the supply port becomes smoother and the supply amount is stabilized, so that a uniform film can be obtained.

  If such an impact sintering method is used, the crystal structure of the raw material powder (yttrium oxide particle slurry containing the oxide of the lanthanoid element) is a yttrium oxide film containing the oxide of the lanthanoid element which has been changed to monoclinic crystal. It can be configured. For example, yttrium oxide is cubic at normal temperature. The crystal structure changes when exposed to high temperatures such as combustion flames, but since the impact sintering method can be jetted at high speed, it is converted to a monoclinic crystal and a yttrium oxide film containing an oxide of a lanthanoid element having high plasma resistance. Can be configured.

  According to the above configuration, the plasma resistance of the plasma etching apparatus component is significantly improved, and particle reduction, impurity contamination reduction, and component life extension can be achieved. Therefore, with a plasma etching apparatus using such a component for a plasma etching apparatus, generation of particles during the plasma etching process and reduction of the number of parts replacement can be achieved.

  In addition, since the particles are sprayed at a high speed by impact sintering and the particles are deposited by the collision energy, no blasting is necessary when depositing a film on the component, and residual of the blast material and surface defects The absence of generation improves the adhesion of the film. This is because the surface oxide film of the component is destroyed by high-speed collision of particles and the active surface is exposed, so that a film is directly formed on the surface of the component, and the particle collision is caused by the subsequent particle collision. It is believed to occur and to form as a film.

  Therefore, the generation of particles due to the peeling of the yttrium oxide film deposited on the part can be effectively suppressed, and the number of device cleaning and part replacement can be significantly reduced. In addition, the reduction of the particle generation amount greatly contributes to the improvement of the yield of various thin films to be etched or formed by a semiconductor manufacturing apparatus, and elements and parts using the thin films. In addition, the reduction of the number of times of device cleaning and parts replacement, and the extension of the service life of parts by eliminating the need for blasting greatly contribute to the improvement of productivity and the reduction of etching cost.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the following examples.

(Examples 1 to 8 and Comparative Example 1)
Various oxide ceramics are added to yttrium oxide under the conditions shown in Table 1 on an alumina base (300 mm × 3 mm) by impact sintering using a combustion flame type injection apparatus to form a plasma Equipment parts. The solvent of the yttrium oxide particles and the slurry of the other oxide particles was all ethyl alcohol. Moreover, as for the raw material powder to be used, high purity oxide particles having a purity of 99.9% or more were used. Further, Y ₂ O ₃ particles as the raw material powder is cubic, using raw material powder no coarse particles of more than 10μm by sufficient grinding and sieving.

Further, Comparative Example 1 is a film formed by plasma spraying using yttrium oxide powder having an average particle diameter of 14 μm as a raw material.

  Next, for each yttrium oxide film formed in each example and comparative example, the film density, the area ratio of particles in which grain boundaries can be confirmed, the area ratio of particles in which grain boundaries can not be confirmed, and grain boundaries in each yttrium oxide film are confirmed The average particle size and crystal structure of the resulting particles were analyzed.

  The film density was determined from the ratio of pores captured in an enlarged photograph (500 ×) such that the total unit area of the film cross section was 200 μm × 200 μm. In addition, the area ratio of particles in which grain boundaries can be confirmed and particles in which grain boundaries can not be confirmed is an enlarged photograph (5000 × magnification) of a unit area of 20 μm × 20 μm on the film surface, and grain boundaries of one yttrium oxide particle are known The area ratio was determined as “particles in which grain boundaries can be identified” and particles in which grain boundaries are combined and not understood as “particles in which grain boundaries can not be identified”. This work was carried out at any three places, and the average value was defined as the area ratio (%) of "particles in which grain boundaries can be identified" and "particles in which grain boundaries can not be identified". In addition, the same enlarged photograph was used to determine the average particle size of "particles whose grain boundaries can be confirmed".

The crystal structure was also investigated by XRD analysis. The XRD analysis was performed using a Cu target at a tube voltage of 40 kV and a tube current of 40 mA, and the ratio (Im / Ic) of the monoclinic strongest peak Im to the cubic strongest peak Ic was investigated. The results are shown in Table 2 below.

  As is clear from the results shown in Table 2 above, the yttrium oxide film containing the oxide of the lanthanoid element according to each example has a high film density, and the ratio (area ratio) of "particles in which grain boundaries can be confirmed" is 0. Within the range of -80%. In addition, by using the impact sintering method, the particles were slightly smaller than the size of the raw material powder. Moreover, since it was not melted more than necessary, the crystal structure was also the same as the raw material powder.

  Moreover, as for surface roughness Ra of the yttrium oxide film in Examples 1-8, all were 0.5 micrometer or less. Moreover, surface roughness Ra of the film in the comparative example 1 was 3.1 micrometers.

Next, components for a plasma etching apparatus according to each example and comparative example were placed in a plasma etching apparatus and exposed to a mixed etching gas of CF ₄ (50 sccm) + O ₂ (20 sccm) + Ar (50 sccm). After setting the inside of the etching chamber to 10 mTorr and operating continuously for 2 hours with an output of 300 W (bias 100 W), the adhesion area ratio of falling off adhering particles by the tape peeling method is evaluated as peeling evaluation for each yttrium oxide film. It was measured. Specifically, a conductive carbon tape was attached to each yttrium oxide film, and then the tape was peeled off, and the tape was subjected to SEM observation to measure the area of each yttrium oxide particle present in the 125 μm × 95 μm field of view. Moreover, the weight change of components before and after conducting the said test was measured, and the weight loss per unit area was calculated | required. The results are shown in Table 3 below.

Moreover, as a result of measuring the volume resistivity of each yttrium oxide film by a four-terminal method (JIS K 7194 conformity) at room temperature (25 ° C.), it was in the range of 1.2 to 1.5 × 10 ¹² Ω · cm.

  As is clear from the results shown in Table 3, it was found that the parts for plasma apparatus according to each example had high resistance to plasma attack and radical attack. Having high resistance to plasma attack and radical attack means that generation of particles can be effectively suppressed when used in a dry etching apparatus. These effects are further improved when a lanthanum-based oxide is added to yttrium oxide.

  In the above examples, although the case where the substrate is made of alumina ceramic is exemplified, it is confirmed by experiments that the same effect is exhibited even when a metal substrate is used.

  As described above, according to the component for a plasma device of the present invention, particles generated from the component can be stably and effectively prevented. Further, since the corrosion of the film to active radicals of the corrosive gas is suppressed, the generation of particles from the film can be prevented, and the generation of particles due to the fall-off prevention can be suppressed together with the reduction of corrosion products. Therefore, the number of times of cleaning of parts for plasma apparatus and replacement of parts can be reduced.

1: Component for plasma processing apparatus 2. Yttrium oxide film containing oxide of lanthanoid element 3. Base material 4: Yttrium oxide particle 5 containing oxide of lanthanoid element 5. No grain boundary can be confirmed. Oxide particles containing oxides of rare earth elements

Claims (16)

The base material is made of metal or ceramic, and the outermost surface on this base material has a film thickness of 10 to 200 μm, a film density of 90% or more, and grain boundaries present in a unit area of 20 μm × 20 μm are confirmed A yttrium oxide film containing an oxide of a lanthanoid element having an area ratio of particles which can be 5 to 80% and an area ratio of particles which can not confirm grain boundaries is 20 to 95%; The film contains 1 to 8% by mass in terms of oxide of at least one selected from lanthanoid elements consisting of La, Ce, Sm, Dy, Gd, Er and Yb , and contains the oxide of the above lanthanoid elements When the yttrium oxide film is subjected to XRD analysis, the ratio (Im / Ic) of the strongest peak Im of monoclinic crystal to the strongest peak Ic of cubic crystal is 0.2 to 0.6, and the lanthanoid Element oxide particles having an average particle diameter and component plasma and wherein the average particle size of the yttrium oxide particles are 0.05~5μm containing an oxide of the lanthanoid element of. The plasma device according to claim 1, wherein the base material is made of a ceramic provided with a metal electrode, and the outermost surface of the base material is provided with a yttrium oxide film containing an oxide of the lanthanoid element. Parts. 3. The plasma device according to any one of claims 1 to 2 , wherein the particles forming the yttrium oxide film containing the oxide of the lanthanoid element have a total average particle size of 5 μm or less. parts. The component for a plasma device according to any one of claims 1 to 3 , wherein the particles forming the yttrium oxide film containing the oxide of the lanthanoid element contain fine particles having a particle diameter of 1 μm or less. . The yttrium oxide film containing an oxide of a lanthanoid element has a film thickness of 10 to 200 μm, and a film density of 99% to 100%, according to any one of claims 1 to 4. Parts for plasma equipment. The component for a plasma device according to claim 1 , wherein the yttrium oxide particles containing an oxide of a lanthanoid element from which the grain boundaries can be confirmed have an average particle diameter of 2 μm or less. Particles forming the yttrium oxide coating containing an oxide of the lanthanoid series element has an average particle size include the 1μm or less of the fine particles, according to claim 1 to 6, wherein the average particle size of the whole is 5μm or less The plasma apparatus component according to any one of the above. Any one of claims 1 to 7, wherein the average particle size of the yttrium oxide particles containing an oxide of average particle size and the lanthanoid element oxide particles of the lanthanoid element is 0.05~5μm The part for plasma apparatuses of 1 item. Yttrium oxide coating containing an oxide of the lanthanoid series element is plasma device component according to any one of claims 1 to 8, characterized in that the table surface roughness Ra is in the 0.5μm or less. The method of manufacturing a plasma instrumentation置用component according to claim 1 formed with the yttrium oxide coating containing an oxide of lanthanoid elements by impact sintering process, yttrium oxide containing an oxide of lanthanoid element combustion flame flame A component for a plasma device, comprising: supplying a slurry containing particles; and injecting yttrium oxide particles containing an oxide of a lanthanoid element onto a substrate at an injection speed of 400 to 1000 m / sec. Manufacturing method. Yttrium oxide particles containing an oxide of lanthanoid elements contained in the slurry of claim 10, wherein the purity of yttrium oxide particles containing an oxide of 99.9% or more lanthanoid elements Method of manufacturing parts for plasma device. Any one of claims 10 to 11, wherein the average particle size of the yttrium oxide particles containing an oxide of average particle size and the lanthanoid element oxide particles of the lanthanoid element is 0.05~5μm The manufacturing method of the components for plasma apparatuses of 1 item. The film thickness of the yttrium oxide film containing the oxide of the said lanthanoid type element is 10 micrometers or more, The manufacturing method of the components for plasma devices of any one of the Claims 10 thru | or 12 characterized by the above-mentioned. The method for producing a plasma device component according to any one of claims 10 to 13 , wherein a slurry containing yttrium oxide particles containing an oxide of the lanthanoid element is supplied to the center of a combustion flame. 10. Temperature of the combustion flame is supplied a slurry containing yttrium oxide particles containing an oxide of the lanthanoid series element, which is characterized in that less than the boiling point of the yttrium oxide particles containing an oxide of lanthanoid element supplying 15. A method of manufacturing a plasma device component according to any one of 14 to 14 . The part for plasma apparatus according to any one of claims 10 to 15, wherein a polishing process is performed to reduce the surface roughness Ra of the yttrium oxide film containing an oxide of the lanthanoid element to 0.5 μm or less. Manufacturing method .

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