JP2002001865A - Laminate, corrosion resistant member and halogen gas plasma resistant member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hardly release a film from a base made of aluminum and to particularly hardly release the film particularly even after the film is contacted with a corrosion substance in a laminate of the base and the film formed on the base. SOLUTION: The laminate comprises the base made of the aluminum and an yttrium compound film formed on the base. The laminate also comprises an intermediate layer made of a reaction product of an alumina with an yttria compound along an interface between the base and the yttrium compound film. The yttrium compound film preferably contains an yttria and is particularly preferably made of the yttria. The product preferably is a composite oxide containing the yttrium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate which can be used as a member for halogen-resistant gas plasma suitable for a chamber wall or a dome (roof) of a semiconductor manufacturing apparatus, for example.

[0002]

2. Description of the Related Art In a semiconductor manufacturing apparatus requiring a super clean state, a halogen-based corrosive gas such as a chlorine-based gas and a fluorine-based gas is used as a deposition gas, an etching gas, and a cleaning gas. ing.

For example, in a semiconductor manufacturing apparatus such as a thermal CVD apparatus, ClF ₃ , NF ₃ , C
A semiconductor cleaning gas composed of a halogen-based corrosive gas such as F ₄ , HF, and HCl is used. Also, at the stage of deposition, a halogen-based corrosive gas such as WF ₆ or SiH ₂ Cl ₂ is used as a film-forming gas. In recent years, to increase the etching rate, etc.,
Tend to use particularly highly corrosive gas such as NF _3.

[0004]

As a result, there is a problem that the wall surface of the chamber for the semiconductor manufacturing apparatus is corroded, particles are generated, and the particles fall on the wafer. In this case, a phenomenon of insulation failure or conduction failure occurs, which causes a semiconductor failure. For this reason, a technique for preventing particles from migrating from a chamber or a dome wall surface to a wafer is desired.

[0005] There is known a technique in which a chamber or a dome is formed of a ceramic such as alumina, and a surface of the chamber or the dome is coated with a corrosion-resistant film. In this case, however, it is essential not only to prevent the generation and dropping of the above-mentioned particles, but also to prevent the corrosion-resistant film from peeling off, particularly after a number of thermal cycles in an environment in which it comes into contact with corrosive substances. It is essential that the corrosion-resistant film does not peel off and adheres firmly to the chamber or dome surface.

An object of the present invention is to provide a laminate of a substrate made of alumina and a film formed on the substrate, wherein the film is difficult to peel off from the substrate, and even after contact with a corrosive substance. An object of the present invention is to provide a laminate in which a film is not easily peeled.

Another object of the present invention is to provide a corrosion-resistant member having high corrosion resistance and capable of being used stably for a long period of time, particularly a member for halogen gas plasma, using this laminate. is there.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a laminate of a substrate made of alumina and a yttrium compound film formed on the substrate, wherein alumina and yttrium compound are formed at an interface between the substrate and the yttrium compound film. It is characterized by the presence of a reaction product with the compound.

The inventor of the present invention has proposed that when a yttrium compound film is formed on an alumina substrate by a specific manufacturing method as described later, a reaction product of alumina and the yttrium compound may be formed along an interface between the two depending on conditions. Found to produce. Then, when such a reaction product was generated, it was found that the yttrium compound film did not peel off even after a thermal cycle between 800 ° C. and room temperature, for example, and the present invention was reached.

This reaction product is usually formed in a layer along the interface between the substrate and the yttrium compound, and constitutes an intermediate layer. However, the layered yttrium compound may be continuous over the entire surface of the interface between the substrate and the yttrium compound, but is generated discontinuously at the interface between the substrate and the yttrium compound, resulting in an island-shaped layered structure. In some cases, a plurality of objects are formed. In this case,
Although the island-like layered materials are not continuous with each other, they exist in layers along the interface as a whole, and constitute an intermediate layer. The present invention also includes the case where the reaction product is scattered or scattered at the interface between the substrate and the yttrium compound. Such a case where the reaction product layer having a small area is scattered or scattered is also included in the present invention. Furthermore, as long as the reaction product can be confirmed by an X-ray diffractometer, it is within the scope of the present invention.

The reaction product preferably contains a crystal phase comprising a composite oxide of yttria and alumina. The type of the composite oxide is not limited, but is, for example, as follows. (1) Y ₃ Al ₅ O ₁₂ (YAG). It contains yttria and alumina at a ratio of 3: 5 and has a garnet crystal structure. (2) YAlO ₃ (YAP). Perovskite crystal structure. (3) Y ₄ Al ₂ O ₉ (YAM). Monoclinic.

Particularly preferably, the intermediate layer is made of yttrium.
Containing a crystal layer consisting of aluminum garnet
And / or even Y_Four Al_Two O₉ (2Y _Two O
_Three ・ Al_Two O_Three ).

Examples of the yttrium compound constituting the yttrium compound film include yttria and solid solutions containing yttria (zirconia-yttria solid solution, rare earth oxide-
Yttria solid solution), complex oxide containing yttria (yttrium aluminum garnet, Y ₄ Al ₂ O ₉
(2Y ₂ O ₃ .Al ₂ O ₃ ), YAlO ₃ (Y ₂ O _3.
Al ₂ O ₃ ), yttrium trifluoride, Y-Al
— (O) —F, Y ₂ Zr ₂ O _{7 and the} like. In particular,
It is preferable that the yttrium compound film contains at least yttria, which includes yttria, a solid solution containing yttria, and a composite oxide containing yttria. In particular, yttria alone or yttrium fluoride is preferred.

Further, the present inventor has a microstructure in which fine particles made of the same material as the intermediate layer and voids formed between the fine particles are arranged along the interface between the intermediate layer and the base. Confirmed that there may be cases. Each void is surrounded by the fine particles forming the intermediate layer and the substrate. When it has such a specific microstructure, the adhesion of the yttria film to the substrate is further improved. This portion is considered to reduce the difference between the Young's modulus of the base and the Young's modulus of the yttrium compound film.

The lower limit of the thickness of the intermediate layer is not particularly limited. Even when the intermediate layer is extremely thin, the peel strength of the corrosion-resistant film is significantly increased as compared with the case where no intermediate layer is formed. It is more preferable that the thickness of the intermediate layer be 3 μm or more from the viewpoint of improving peel strength.

The thickness of the intermediate layer has no particular upper limit.
Actually, those having a size of 30 μm or less are easy to manufacture. By setting the thickness of the intermediate layer to 20 μm or less, the peel strength of the yttrium compound film becomes particularly large. From this viewpoint, it is more preferable that the thickness of the intermediate layer be 15 μm or less.

When the yttrium compound film is used for applications requiring high purity, especially for semiconductor manufacturing equipment, the yttrium compound must have a low content of alkali metals, alkaline earth metals and transition metals. It is preferable that the total value is 100 ppm or less,
More preferably, it is 30 ppm or less. This content is measured by quantitative analysis using inductively coupled plasma (ICP).

In particular, it is preferable that the concentration of iron atoms in the yttrium compound film is 30 ppm or less (content of iron atoms alone).

It has been found that even if a small amount of iron atoms is mixed in the yttrium compound film, noticeable fine spots are formed on the surface of the film. In order to prevent such fine spots, the concentration of iron atoms in the corrosion resistant film needs to be 20 ppm or less.

In order to manufacture the laminate of the present invention, a sprayed film is formed by spraying a yttrium compound film on a substrate or a precursor thereof, and the sprayed film is heat-treated.

The substrate may be made of dense alumina after sintering, or may be a porous sintered body of alumina. Further, an alumina substrate can be formed by forming a paste layer or a coating layer containing alumina on another base material and sintering the paste layer or the coating layer by a subsequent heat treatment. The shape of the substrate is not particularly limited, and may be a plate, a film, or the like.

Preferably, the substrate is porous. Preferably, the center line average surface roughness Ra of the substrate surface is 1 μm.
(More preferably 1.2 μm or more). As a result, the adhesion of the corrosion resistant film to the base is enhanced, and the generation of particles due to the peeling of the film can be prevented.

By using a porous body as the substrate, the Young's modulus of the substrate can be relatively suppressed as compared with the case of using a dense body, and the adhesion of the yttrium compound film to the substrate can be further improved. Can be strong.
In particular, if open pores are formed on the surface of the base with a small opening and a widened interior, particles melted during the thermal spray enter the open pores, solidify in the open pores, and form a sprayed film on the surface. It has the effect of fixing.

When spraying the yttrium compound film on the substrate, the spraying is preferably performed at a low pressure, and the pressure is preferably 100 Torr or less. Thereby, the pores of the sprayed film can be further reduced, and the corrosion resistance of the final film can be further improved.

After the sprayed film is formed, the sprayed film and the substrate or a precursor thereof are subjected to a heat treatment, so that at least the sprayed film is further sintered, and pores in the sprayed film are eliminated or reduced. In forming the intermediate layer, the heat treatment temperature is 130
0 ° C. or higher is preferred. The upper limit of the heat treatment temperature is 1800 ° C
The following is preferred. The heat treatment time is preferably one hour or more.

The rate of temperature rise during the heat treatment is preferably 1200 ° C. or more and 200 ° C./hour or less in order to uniformly heat and react the substrate and the film temperature. The temperature decreasing rate is preferably 200 ° C./hour or less in order to prevent cracking of the substrate and the film. The heat treatment atmosphere may be air. The thickness of the intermediate layer and the size of the crystal grains of the yttrium compound film can be controlled by the heat treatment time and the heat treatment temperature. The longer the heat treatment time and the higher the temperature, the thicker the intermediate layer and the larger the crystal grains.

It should be noted that since yttria and alumina have similar thermal expansion coefficients, performing special heat treatment to reduce the difference in thermal expansion between them has not been noticed so far. It is.

The present inventor has further found that the peel strength of the corrosion resistant film is significantly increased by setting the heat treatment temperature of the thermal sprayed film to 1400 ° C. or more. Heat treatment temperature 140
When the temperature reaches 0 ° C., a reaction layer is easily generated between the material of the main body and the material of the corrosion-resistant film, and as a result, it is considered that the peel strength of the corrosion-resistant film is improved.

On the other hand, the heat treatment temperature of the sprayed film increases,
When the temperature approaches 800 ° C., movement and diffusion of the aluminum element in the vicinity of the once formed reaction layer occur, and on the contrary, the peel strength of the corrosion-resistant film may decrease. From this viewpoint, the heat treatment temperature is preferably 1650 ° C. or less,
1600 ° C. or lower is more preferable, and 1550 ° C. or lower is particularly preferable.

Preferably, the peel strength of the yttrium compound film to the substrate is 15 MPa or more when the diameter of the bonding surface is measured to be 5.2 mm in diameter according to a test described later.

For example, it has been found that, in the laminate heat-treated as described above, the peel strength of the yttrium compound film to the substrate reaches 15 MPa or more, for example, a peel strength of 35 MPa or more can be realized. In particular, 1500
When the heat treatment was performed at a temperature of 1600C to 1600C, a high peel strength of 20 MPa or more, and more preferably 35 MPa or more was obtained.

Further, an alumina powder layer, a layer of a mixed powder of yttrium compound powder (for example, yttria powder) and alumina powder, and a layer of yttrium compound powder (for example, yttria powder) are sequentially laminated to obtain a laminated molded article. By co-sintering the laminated molded body at 1500 to 1800 ° C., the laminated body of the present invention can be manufactured.

An object in which the corrosion-resistant member exhibits corrosion resistance is a semiconductor manufacturing apparatus such as a thermal CVD apparatus. In such a semiconductor manufacturing apparatus, a semiconductor clean gas composed of a halogen-based corrosive gas is used. It has corrosion resistance not only in a halogen gas plasma but also in a plasma atmosphere of a gas mixture of a halogen gas and an oxygen gas. It can be applied as a semiconductor manufacturing device.

As the halogen gas, ClF_Three , NF
_Three , CF_Four , WF₆ , Cl _Two , BCl_Three Etc.
You.

The center line average surface roughness Ra of the yttria compound film is preferably 3 μm or more, and the undulation Wa is preferably 1 μm or more. As a result, it is possible to make it difficult for particles due to corrosion of each member in the semiconductor manufacturing apparatus and wafer processing dust to float in the space inside the container or to fall and accumulate on other members in the container.

This is because while the yttrium compound film acts as a material that hardly generates particles,
By increasing Ra of the yttrium compound film (leaving surface irregularities), a small amount of particles generated by corrosion or wafer processing are retained on the surface of the yttrium compound film, and float on the space, fall, and deposit on other members. Seems to escape.

Here, a large (rough) Ra on the surface of the corrosion resistant film means that the surface has irregularities. Looking at this surface microscopically,
There is a convex part adjacent to this concave part,
The projections are composed of particles projecting from the depressions. Therefore, when Ra on the surface of the corrosion-resistant film is increased, the plasma of the halogen gas penetrates into the concave region of the surface and corrodes the grain boundary from the root of the convex portion (particle), so that the generation of particles is rather promoted. I thought. However, the increase in the number of particles is small, and the floating and falling of the particles into the space in the container are rather prevented.

If Ra is too large, corrosion of the film surface is promoted and particles increase rather. From this viewpoint, Ra is preferably set to 6 μm or less.
The undulation Wa of the film is preferably 3 μm or less.

[0039]

EXAMPLES (Comparative Example 1) (Production method) An alumina substrate (dimensions: 10 mm × 10 mm × thickness: 2 mm) having a purity of 99.6% by weight and an open porosity of 0.1% or less was subjected to ultrasonic cleaning with acetone, and the purity was adjusted. 99.9% by weight of yttria was sprayed. The thermal spraying conditions are as follows. That is,
Argon is flowed at a flow rate of 40 liters / minute, and hydrogen is
Flow at a flow rate of 1 liter / min, the spraying power is 40 kW,
The spray distance was 120 mm. In the following examples and comparative examples, the thermal spraying conditions were the same.

The sprayed film thickness was 48 μm. The thickness of the sprayed film was calculated by measuring the thickness of the sample before and after spraying with a micrometer, and calculating the difference between the thicknesses of the sample before and after spraying based on the measured average value of five points. The difference between the maximum value and the minimum value of the measured film thickness was 9 μm. No heat treatment was performed on the sprayed material.

(Evaluation Results) The state of the film was observed with a scanning electron microscope, an energy dispersive X-ray spectrometer, and an X-ray diffractometer.

(Surface) The crystal phase of the yttria film was analyzed by an X-ray diffractometer. X-rays were incident from above the film.
The crystal phase of yttria was monoclinic (Monoclinic) in addition to cubic (Cubic). The surface of the sprayed film has a length
Cracks of 5 to 10 μm and width of about 0.1 to 0.5 μm were observed. There were 3 to 5 cracks per 100 μm ² (see FIG. 2).

(Cross Section) A layered structure is seen in the yttria film (FIG. 3). Since it has a layered structure, it was expected that the structure was easy to peel off. About 1-5 μm
Pores were observed. However, there was no through-hole from the membrane surface to the alumina substrate.

(Surface Roughness) The center line average surface roughness Ra of the film surface was 3.5 μm. (Undulation) Wa (undulation average) was 2.5 μm.
However, Ra and Wa are Taylor Hobson's “Form Tal
The measurement was performed with a scan length of 4.8 mm using "ysurf 2 S4".

(Peel Test) A test was conducted in which Nychiban tape "Nystack" was attached to the film and peeled off. As a result, the film was peeled over the entire surface and stuck to the tape side.

(Peeling Strength) The film-formed sample is cut into a thickness of 10 mm × 10 mm × 2 mm (including the thickness of the yttrium compound film). 2. The cut sample is ultrasonically washed with acetone for 5 minutes. 3. Prepare an Al stud pin (made by Phototechnica Co., Ltd.) with an epoxy adhesive. This bonding area has a diameter of φ5.
It has a circular shape of 2 mm. 4. A stud pin is brought into contact with the yttrium compound film,
After heating at 150 ° C for 1 hour, the stud pin and the yttrium compound film are bonded and fixed with an epoxy adhesive. 5. The stud pins and the laminate are fixed to the upper and lower chuck portions of the tensile tester. In the autograph, the stud pin and the laminate are pulled at a speed of 0.5 mm / min and pulled up until the yttrium compound film comes off. The adhesive strength is calculated from the load when the film is peeled off and the adhesive area (peel strength = peel load / adhesive area of the pin). At this time, the value of the sample peeled at the site of the adhesive is not a measured value.

(Polishing) When the surface of the film was roughly polished with a # 140 diamond grindstone, the film was peeled off.

(Corrosion Resistance Test) This sample was kept at 735 ° C. for 2 hours in ClF ₃ downflow plasma. The flow rate of ClF ₃ gas is 75 sccm, and the flow rate of carrier gas (nitrogen gas) is
It was 100 sccm. Inductively coupled plasma (13.56Hz, output
800 W) and the gas pressure was set to 0.1 Torr. After that, when the cross section was observed with a scanning electron microscope, the film was peeled off from the substrate.

(Thermal cycle test) 10 cycles of heating
A cooling cycle was performed. In one cycle, the sample was heated at 800 ° C./min to 800 ° C., heated at 800 ° C. for 1 hour, rapidly returned to room temperature at 400 ° C./min, and
Heated at C for 1 hour. After this, the weight change of the sample is 0.
It was ² mg / cm ² . Thereafter, when the Peel test was performed, the film was peeled over the entire surface.

(Example 1) (Production method) On an alumina substrate (dimensions: 10 mm x 10 mm x thickness 2 mm) having a purity of 99.6% by weight and an open porosity of 0.1% or less, a purity of 99.9%. Weight percent yttria was sprayed. The thickness of the sprayed film was 46 μm. The difference between the maximum value and the minimum value of the measured film thickness was 15 μm. After spraying, the sample
Heat treatment was performed at 00 ° C. for 3 hours in an air atmosphere. The heating rate is
At 1200 ° C. or higher, the temperature was 200 ° C./hour. Further, the temperature decreasing rate was 150 ° C./hour.

(Surface) It had a structure in which yttria particles having a diameter of 1 to 3 μm were sintered (FIG. 4). The crystal phase of the yttria film was analyzed with an X-ray diffractometer. X from above the membrane
A line was incident. Cubic Y ₂ O ₃ was detected. The half-width of the peak on the surface of the heat-treated film was smaller than the half-width (FWHM) of the diffraction peak of the unheated product (Comparative Example 1). This indicates that the heat treatment at 1600 ° C. increased the crystallinity of the film yttria. Table 1 shows the full width at half maximum of the main diffraction peak of cubic yttria of Example 1 and the sample not subjected to the heat treatment (Comparative Example 1).

[0052]

[Table 1]

(Cross section) There was no peeling of the film. About 1-5μ
m pores were observed. However, there was no through hole from the film surface to the alumina substrate (FIG. 5). The layer structure seen in the yttria film before the heat treatment disappeared.

(Interface between Yttria Film and Alumina Substrate) A reaction layer of about 10 μm was formed at the boundary between the yttria film and the alumina substrate (FIG. 5). It was confirmed by analysis with an energy dispersive X-ray spectrometer that this reaction layer was formed by the reaction between alumina and yttria. Also, from the result of X-ray diffraction, the crystal phase of the reaction layer was Y ₃ Al ₅
O ₁₂ (YAG) and Y ₄ Al ₂ O ₉ (YAM) were found. Denseness of alumina substrate (open porosity 0
%) And the porosity of the sprayed yttria film, the alumina (Al ₂ O ₃ ) of the alumina
₂ O ₃₎ is presumed to have diffused towards. At the boundary between the reaction layer and the alumina substrate, there are fine particles of 1-2 μm and voids. This void is surrounded by the fine particles forming the reaction layer and the alumina base material. Since the alumina base material and the reaction layer are in contact with each other via the fine particles, it is expected that the adhesion will be deteriorated, but the difference in the Young's modulus between the reaction layer and the alumina base material is reduced, and the separation becomes difficult. Was expected.

FIG. 1 (Attachment) shows the cross-sectional structure of the film that matches the observation results obtained with a scanning electron microscope, an energy dispersive X-ray spectrometer, and an X-ray diffractometer. On the alumina substrate, a reaction layer of alumina and yttria is about 10 μm, and further thereon is a yttria film.

(Surface Roughness) The center line average surface roughness Ra of the film surface was 4.3 μm. (undulation)

(Peel test) A test was conducted in which a Nychiban tape "Nystack" was attached to the film and peeled off. As a result, the film did not peel off.

(Polishing) The film surface was roughly polished with a # 140 diamond grindstone. There was no peeling of the film at the interface. Further, the film was polished with a # 1000 grindstone, but there was no peeling of the film at the interface (there was no peeling of the film confirmed by the Peel test).

(Corrosion Resistance Test) In the same manner as in Comparative Example 1, ClF
_A corrosion resistance test was performed in ₃ down-flow plasma. After the test, the weight of the sample was measured with an analytical balance.
It was ² mg / cm ² or less. Further, when the cross section was observed with a scanning electron microscope, there was no peeling of the film. further,
The Peel test was performed, but there was no delamination.

(Heat cycle test) A heat cycle was performed in the same manner as in Comparative Example 1. Thereafter, the weight change of the sample was 0.2 mg / cm ² or less. Further, the Peel test was performed, but no peeling of the film was found.

The coefficients of thermal expansion (ppm / k) of alumina, YAG and yttria are 8.5, 8.4 and 8.1. In the sample manufactured in this example, the coefficient of thermal expansion is gradually inclined from the substrate to the film. This was presumed to be one of the causes of no peeling of the film in the heat cycle test.

(Examples 2 to 10) A sprayed film thickness of about 50
100100 μm samples at 1600 ° C. for 3 hours to 10
Table 2-5 shows the evaluation results of the samples that were heat-treated for hours. In addition, Ra of each substrate surface was changed as shown in the table by sandblasting the substrate surface before thermal spraying.

[0063]

[Table 2]

[0064]

[Table 3]

[0065]

[Table 4]

[0066]

[Table 5]

In Example 2, heat treatment was performed at 1600 ° C. for 3 hours (the same as in Example 1). However, the thickness of the sprayed film is as large as 88 μm. The results were the same as in Example 1. In Example 3, the sprayed film was heated at 1700 ° C. for 3 hours.
Heat treated for hours. The result was almost the same as in Example 1, but the reaction layer was slightly thicker. In Example 4, a slightly thick sprayed film was processed under the same heat treatment conditions as Example 3.
The results were the same as in Example 3. In Examples 5 and 6, the heat treatment temperature of the thermal sprayed film was 1600 ° C., and the treatment time was slightly extended to 5 hours. As a result, substantially the same results as in Examples 1 and 2 were obtained, but the thickness of the reaction layer was slightly increased.

In the seventh, eighth, ninth and tenth embodiments, the processing time is further extended as compared with the fifth and sixth embodiments. As a result, the longer the processing time, the thicker the intermediate layer was.

For Example 3 (heat treatment at 1700 ° C. for 3 hours), a scanning electron micrograph of the surface of the sample is shown in FIG. 6, and a scanning electron micrograph of a cross section near the interface between the yttria film and the alumina substrate is shown. As shown in FIG. The yttria film has a structure in which 2-5 μm-based yttria particles are sintered, and the grain growth has progressed as compared with the case where the heat treatment is performed at 1600 ° C. Further, the microstructures of the film, the intermediate layer, and the substrate were almost the same as those in Example 1.

(Examples 11 to 12) (Production method) A commercially available alumina powder was molded and calcined, and had a density of 3.56 g / cm ³ , a porosity of about 10% (Example 11) and a density of 3.76 g / cm ^3. Porosity about 5% (Example 12)
(Examples 1 to 10; Comparative Example: density 3.96 g / cm
³ ) An alumina substrate was prepared. Yttria having a purity of 99.9 wt% was sprayed on the alumina substrate. The size of the alumina substrate is 10 × 10 × 2 mm.
The sprayed film thickness was 91 μm. The thickness of the sprayed film was obtained by measuring the thickness of the sample before and after spraying with a micrometer, and calculating the difference between the thicknesses of the sample before and after spraying based on the measured average value at five points. The difference between the maximum value and the minimum value of the measured film thickness is 1
It was 9 μm. The sample after this thermal spraying was
Heat treatment was performed in air atmosphere for hours. The heating rate is 1200
At 200 ° C. or higher, the temperature was 200 ° C./hour. The cooling rate is 15
0 ° C./hour.

The same test as in Examples 1 to 10 was performed on the obtained sample. The results are shown in Tables 6 and 7. Table 6,
7, the following was found. When heated at 1600 ° C., the density of the alumina substrate became 3.9 g / cm ³ or more. It was found that the yttria film did not peel off even when the alumina substrate contracted due to the heat treatment. Also,
The Peel test was performed in the same manner as in Examples 1 to 12, but there was no peeling. It was presumed that the structure of the fine particles comprising YAG and YAM and the voids in the reaction layer alleviated the shrinkage distortion caused by the heat treatment of the alumina substrate and the yttria film, thereby forming a film having high adhesion.

[0072]

[Table 6]

[0073]

[Table 7]

(Examples 13-16) Each sample produced under the same thermal spraying conditions as in Example 1 was subjected to the following heat treatment to obtain each sample, and the characteristics were evaluated as in Example 1. The density of alumina and the thickness of the sprayed film before the heat treatment are the same as those in Example 1.

[0075]

[Table 8]

In any of Examples 13 to 16, the film after the heat treatment did not peel off in the Peel test. The surface of the membrane is
It was composed of sintered particles having a particle size of 1-3 μm and had no cracks. The cross section of the membrane had 1-5 μm pores. The surface and cross-sectional structure were the same as in Example 1.

Table 8 shows the surface roughness (Ra), waviness (Wa), thickness of the reaction layer, and peel strength of the film. Heat treatment temperature
By setting the holding time to 3 hours at 1400 to 1550 ° C,
High peel strength of 40 MPa or more was obtained.

(Quantitative Determination of Impurity Metal Element in Yttrium Compound Film) The amount of impurity metal element in the film of the material of Example 1 was determined by a glow discharge mass spectrometer (GDMS). Table 9 shows the quantitative values.

[0079]

[Table 9]

The total content of both alkali metal elements and alkaline earth metal elements is 10 ppm or less. The total content of transition metal elements other than yttrium is 50 ppm or less.

(Production of Laminate by Co-Sintering Method) Yttria powder is charged into a mold having a cylinder inner diameter of 60 mm,
It was molded under a load of 20 MPa. With the yttria molded body remaining in the mold, a mixed powder (3: 5 in molar ratio) of yttria powder and alumina powder was charged, molded and laminated. Further, alumina powder was charged, molded and laminated. The average particle size of the used yttria powder is 2 μm, and the average particle size of the alumina powder is 0.6 μm. The thickness of the yttria layer is 1mm
The thickness of the mixed powder layer was 0.8 mm, and the thickness of the alumina layer was 5 mm. The molded body thus produced is further subjected to a hydrostatic press (CI) under a pressure of 200 MPa.
P) After molding, bake at 1700 ° C for 3 hours in air,
A sintered body was produced.

With respect to the obtained sintered body, microstructure observation, identification of a crystal phase, Peel test and peel strength measurement were performed. As a result of observing the surface and the cross section, no through crack was observed from the yttria layer to the alumina base layer. Observation of the cross-sectional microstructure and measurement of the crystal phase by an X-ray diffractometer revealed the formation of a YAG (Y3Al5O12) phase between the yttria layer and the alumina layer. No peeling was observed by the peel test. The peel strength was 40 MPa.

[0083]

As described above, according to the present invention,
A laminated body of a substrate made of alumina and a yttrium compound film formed on the substrate, wherein the film is hardly peeled off from the substrate, and is particularly hard to peel off even after coming into contact with a corrosive substance. Can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a structure near an intermediate layer.

FIG. 2 is a photograph (magnification: 5000) of the surface of the sample of Comparative Example 1 taken by a scanning electron microscope.

FIG. 3 is a photograph (1000-fold magnification) taken by a scanning electron microscope showing a cross section of the sample of Comparative Example 1.

FIG. 4 is a photograph taken by a scanning electron microscope (magnification: 5000) showing the surface of the sample of Example 1 (heat treatment at 1600 ° C. for 3 hours).

FIG. 5 is a photograph (1000-fold magnification) taken by a scanning electron microscope showing a cross section of the sample of Example 1 (heat treatment at 1600 ° C. for 3 hours).

FIG. 6 is a photograph (magnification: 5000) of the surface of the sample of Example 3 (heat treatment at 1700 ° C. for 3 hours) taken by a scanning electron microscope.

FIG. 7 is a photograph taken by a scanning electron microscope (1000 times magnification) showing a cross section of a sample of Example 3 (heat treatment at 1700 ° C. for 3 hours).

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masafumi Harada 2-56, Sudacho, Mizuho-ku, Nagoya, Aichi Prefecture Inside Nihon Insulators Co., Ltd. No. 56 Inside Japan Insulators Co., Ltd. (72) Inventor Hiroyuki Iwasaki No. 2-56, Suda-cho, Mizuho-ku, Nagoya-shi, Aichi F-term in Japan Insulators Co., Ltd. BA03 BA10A BA10B DD07B DE01D DJ10D EH56 GB41 JA11C JB02 JK06 YY00B 5F045 AA03 BB08 BB15 EB03

Claims (17)

[Claims] 1. A laminate of a substrate made of alumina and a yttrium compound film formed on the substrate, wherein a reaction between the alumina and the yttrium compound along an interface between the substrate and the yttrium compound film. A laminate characterized in that the product is present. 2. A laminate of a substrate made of alumina and an yttrium compound film formed on the substrate, wherein a reaction between the alumina and the yttrium compound along an interface between the substrate and the yttrium compound film. A laminate comprising an intermediate layer comprising a product. 3. The laminate according to claim 1, wherein the yttrium compound contains yttria. 4. The laminate according to claim 1, wherein said yttrium compound contains yttrium fluoride. 5. The laminate according to claim 1, wherein the reaction product includes a crystal phase composed of a composite oxide of yttria and alumina. 6. The laminate according to claim 5, wherein said reaction product contains a crystal phase composed of Y ₃ Al ₅ O ₁₂ . 7. The laminate according to claim 5, wherein said reaction product contains a crystal phase composed of Y ₄ Al ₂ O ₉ . 8. A laminate of a substrate made of alumina and a yttrium compound film formed on the substrate, wherein a composite of yttria and alumina is formed along an interface between the substrate and the yttrium compound film. A laminate comprising an intermediate layer containing a crystal phase composed of an oxide. 9. The laminate according to claim 8, wherein said yttrium compound contains yttria. 10. The laminate according to claim 8, wherein the yttrium compound contains yttrium fluoride. 11. The laminate according to claim 8, wherein the intermediate layer includes a crystal phase composed of Y ₃ Al ₅ O ₁₂ . 12. The laminate according to claim 8, wherein the intermediate layer includes a crystal phase composed of Y ₄ Al ₂ O ₉ . 13. A fine structure in which fine particles made of the same material as the intermediate layer and voids formed between the fine particles are arranged along the interface between the intermediate layer and the base. The laminate according to any one of claims 2 to 12, characterized in that: 14. The yttrium compound film according to claim 1, wherein the surface of the yttrium compound film has a center line average surface roughness Ra of 3 to 6 μm and a waviness Wa of 1 to 3 μm. The laminate according to claim. 15. The peel strength of the corrosion-resistant film from the main body is set to a value of φ5.
The laminate according to claim 1, wherein the laminate is 15 MPa or more when measured as 2 mm. 16. A corrosion-resistant member comprising the laminate according to claim 1 as a substrate. 17. A member for a halogen-resistant gas plasma exposed to a halogen gas plasma, wherein the member is a halogen-resistant plasma.
A member for halogen-resistant gas plasma, comprising the laminate according to any one of claims 1 to 4 as a substrate.