JP2004123435A - Black silica glass component and its manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a black silica glass component which flexibly adapts to various shapes and specifications and shows no deterioration caused by crystallization, and its manufacturing process. <P>SOLUTION: The silica glass component has a thermal spraying film of black silica glass formed by using an inert gas or an inert gas containing hydrogen gas and/or hydrocarbon gas. When used as a component of an oxidation diffusion treatment apparatus, a CVD treatment apparatus or a lamp annealing apparatus, the silica glass component saves energy and realizes a high throughput over a long time, due to its a high thermal insulation property and the absence of crystallization in the black silica glass part. This solves the problem wherein a conventional black silica glass component crystallizes and deteriorates when used at a heated part in a chamber, a bell jar, etc. in the oxidation diffusion treatment apparatus, the CVD treatment apparatus or the lamp annealing apparatus used for manufacturing a semiconductor. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a quartz glass part sprayed with black quartz glass, and more particularly to a quartz glass part suitable as a constituent member of various heat treatment apparatuses used in a semiconductor manufacturing field, and a method of manufacturing the same.
[0002]
[Prior art]
Oxidation diffusion processing equipment, CVD processing equipment, lamp annealing equipment, etc. used in semiconductor manufacturing have a structure in which a silicon wafer is heated in a chamber or bell jar, and quartz glass is mainly used as the material of the chamber and bell jar. Have been. In these apparatuses, a serious problem is a reduction in thermal efficiency due to the dissipation of heat from the apparatus, and a reduction in the processing quantity (throughput) per unit time due to the reduction.
[0003]
As means for solving these problems, a method of improving thermal efficiency by blackening quartz glass itself to enhance light shielding properties or far-infrared radiation, or a method of increasing a heating rate have been proposed. (For example, see Patent Document 1)
As a method of blackening the quartz glass itself, a method of adding a V, Mo, Nb compound, carbon, or the like to a quartz glass raw material, mixing and heating and melting the quartz glass material is known. (For example, see Patent Documents 2, 3, and 4) In such a black quartz glass, it is necessary to prevent oxidation of a substance added for blackening, and thus it is necessary to melt in a reducing atmosphere or vacuum. Was. (For example, see Patent Document 5)
In such a conventional black quartz glass, when used at a high temperature in a semiconductor manufacturing apparatus, there is a problem that a metal element added for blackening contaminates the inside of the chamber. Further, the black quartz glass component manufactured by such a method has a problem that when used in a high temperature portion of a semiconductor manufacturing apparatus, it is easily crystallized and deteriorated.
[0004]
Therefore, as a solution to such a problem, black quartz glass and transparent quartz glass are laminated, filled in a heat-resistant mold, and heated and melted in a vacuum furnace to cover the surface of the black quartz glass with transparent quartz glass. Proposed. However, in the case of black quartz glass laminated inside transparent quartz glass by such a method, crystallization was not necessarily sufficiently suppressed. Further, since the production in a vacuum furnace is required, the production method is complicated, the size of the obtained parts is limited, and it is not possible to cope with parts having a complicated shape.
[0005]
On the other hand, as a method for producing black quartz glass, quartz glass placed in a heating furnace is heated to a high temperature of 1900 ° C. or more, and fused with an oxyhydrogen flame or an electric arc flame while supplying quartz glass powder or quartz powder to the upper surface. An application of the method of wearing and overlaying is considered. However, the method using oxyhydrogen flame does not solve the problem of crystallization of black quartz glass. Further, in this method, since the accuracy of the thickness and width of the build-up portion cannot be controlled, machining is required after the build-up, and it has been difficult to manufacture a large quartz glass part.
[0006]
[Patent Document 1]
JP-A-2002-75901
[Patent Document 2]
JP-A-54-157121
[Patent Document 3]
JP-A-5-262535
[Patent Document 4]
JP-A-5-306142
[Patent Document 5]
JP-A-5-262535
[Patent Document 6]
2000-256037
[Patent Document 7]
Japanese Patent No. 3114835
[0007]
[Problems to be solved by the invention]
Conventionally, when a black quartz glass part is used in a portion heated to a high temperature, there has been a problem that it is easily deteriorated by crystallization. In addition, since black quartz glass parts have conventionally been produced by melting in a vacuum furnace or the like, it is necessary to optimize the mold and manufacturing conditions for each product type, and the size and shape of the obtained parts are limited. An object of the present invention is to provide a black quartz glass part which can flexibly correspond to various shapes and specifications and does not deteriorate due to crystallization, and a method of manufacturing the same.
[0008]
[Means for Solving the Problems]
The present inventor has conducted intensive studies in view of the above-mentioned situation, and as a result, has found that a black quartz glass sprayed film is formed on a surface of a quartz glass substrate by an inert gas, or an inert gas and a hydrogen gas and / or a hydrocarbon. The quartz glass parts formed by plasma spraying using a gas mixture of gas have the same or better light-shielding and heat-shielding properties as conventional black quartz glass parts, and have been found to be free from deterioration due to crystallization. The invention has been completed.
[0009]
Hereinafter, the present invention will be described in detail.
[0010]
The quartz glass part of the present invention is a quartz glass part in which a sprayed film of black quartz glass is formed on a quartz glass substrate.
[0011]
Quartz glass parts are used for chambers and bell jars used in oxidation diffusion processing equipment, CVD processing equipment, lamp annealing equipment, etc. Must include parts requiring thermal insulation. However, this does not prevent the black quartz glass from being sprayed on other portions. When the sprayed black quartz glass film is formed on the entire surface or a part of the quartz glass substrate, it has far-infrared radiation as well as light-shielding and heat-shielding properties.
[0012]
The shape of the quartz glass substrate to be used is not limited, and the present invention can correspond to any shape such as a flat plate, a dome, a ring, and a tube.
[0013]
The material of the quartz glass substrate is not particularly limited, but it is a quartz glass material formed by purifying natural quartz and melting it in an oxyhydrogen melting furnace or a plasma melting furnace for use in a semiconductor manufacturing apparatus requiring strength and purity. Alternatively, a high-purity quartz glass material such as a synthetic quartz glass material obtained by hydrolyzing silicon tetrachloride with an oxyhydrogen flame is preferable.
[0014]
The transparency of the quartz glass substrate can be either transparent or opaque. When opaque quartz glass is used as a quartz glass substrate, infrared rays are scattered and visible light is not transmitted, so that the heat shielding effect is particularly enhanced.
[0015]
The thickness of the quartz glass substrate is not particularly limited, but is preferably 0.5 mm or more so as not to be broken by the pressure of the plasma jet at the time of forming the sprayed film, and 30 mm or more so as not to be broken by thermal shock at the time of spraying. The following is preferred.
[0016]
Next, the quartz glass of the present invention has a sprayed film of black quartz glass formed on a quartz glass substrate. The black quartz glass refers to a quartz glass that exhibits a black color and does not transmit visible light, ultraviolet light, and infrared light due to being black. The term “black” is not limited to pure black by visual observation, but includes those having different color tones such as dark green and dark purple and having the same light shielding effect as black. The light transmittance is preferably 1% or less at a wavelength of 185 to 25000 nm. Further, it is preferable that at least one element selected from the group consisting of Nb, V, Mo and C is included as a blackening element of the sprayed black quartz glass film. The addition amount of the blackening element in the sprayed film is not particularly limited, but it is sufficient to use 0.1 wt% or more and 10 wt% or less in the sprayed film.
[0017]
The thickness of the sprayed black quartz glass film differs depending on the blackening element and the amount of addition, but is preferably 0.3 mm or more in order to exhibit light shielding properties and far-infrared radiation.
[0018]
One of the features of the sprayed film of black quartz glass of the present invention is that there is no problem of crystallization as compared with the conventional black quartz glass. For a quartz glass part having a sprayed film of black quartz glass, although the exact reason is not clear, deterioration due to crystallization was not observed by heating in an oxidizing atmosphere. Possible reasons are that the black quartz glass part of the present invention is a sprayed film, and therefore has a different tissue structure from the conventional fused quartz glass, or an inert gas, or an inert gas and a hydrogen gas and / or a hydrocarbon. Since the film is formed by plasma spraying of a mixed gas of gases, it is conceivable that reducing gas is taken into the sprayed film, which suppresses crystallization.
[0019]
Next, the quartz glass part of the present invention is a quartz glass part in which a transparent quartz glass sprayed film and / or an opaque quartz glass sprayed film are laminated on the black quartz glass sprayed film.
[0020]
By laminating the sprayed quartz glass film on the sprayed black quartz glass film, the effect of preventing contamination in the chamber due to the blackening element can be enhanced. In order to particularly enhance the protection performance of the sprayed black quartz glass film in the chamber, the thickness of the sprayed quartz glass film on the sprayed black quartz glass film is preferably 0.3 mm or more. Although there is no limitation on the thickness of the sprayed film to be laminated, a thickness of 1 to 3 mm is sufficient. By laminating the sprayed quartz glass film in this manner, impurities can be prevented from being mixed due to mechanical abrasion of the sprayed black quartz glass film, and a barrier that prevents impurities from the base material from being thermally diffused can be obtained. Also.
[0021]
The quartz glass to be laminated can be either transparent or opaque. The opaque quartz glass may be made opaque by adding some element or made opaque by having bubbles, but it is preferable to use opaque quartz glass for the purpose of preventing diffusion of impurities.
[0022]
When the opaque quartz glass sprayed film is laminated on the black quartz glass sprayed film, infrared rays are scattered and visible light is not transmitted, so that the heat shielding effect can be further enhanced. The lamination of these sprayed films of quartz glass can also be expected to have the effect of further reducing the chance of crystallization of the sprayed film of black quartz glass.
[0023]
Next, a method for manufacturing a quartz glass component of the present invention will be described.
[0024]
The quartz glass component of the present invention is formed of a quartz glass substrate or formed by a plasma jet using a plasma spraying method using an inert gas or a mixed gas of an inert gas and a hydrogen gas and / or a hydrocarbon gas as a plasma gas. It can be manufactured by spraying while melting the surface of the sprayed film.
[0025]
In the present invention, a plasma sprayed film is formed by using an inert gas alone or a mixed gas of an inert gas, a hydrogen gas and / or a hydrocarbon gas as a plasma gas. In such thermal spraying using a plasma gas containing no oxygen or containing a reducing gas, it is possible to obtain a good black quartz glass sprayed film without oxidizing an element or compound (eg, NbO2) added for blackening. Can be. Although it is difficult to confirm by ordinary analysis methods, it is thought that crystallization caused by the blackening additive is suppressed by introducing a trace amount of these gas components, particularly reducing hydrogen gas, into the sprayed film. Can be Further, by adding the hydrocarbon gas, it is possible to suppress the carbon from reacting with the quartz and dissipating.
[0026]
Examples of the inert gas include helium, neon, argon and the like, but it is preferable to use argon industrially. When hydrogen gas is added, the concentration is preferably in the range of 5 to 50%, particularly preferably 5 to 30%. Examples of the hydrocarbon gas include methane, ethane, propane, ethylene, and acetylene, and the concentration thereof is preferably 5 to 50%, particularly preferably 5 to 30%.
[0027]
In the present invention, the quartz glass substrate surface is sprayed while being melted by the plasma jet. The melting temperature of quartz glass is 1800 ° C. or higher. When forming a sprayed film, the surface of the quartz glass substrate is irradiated with a plasma jet, and the raw material powder is supplied and sprayed while melting the surface, so that the sprayed raw material powder is melted by the plasma jet. Collision can be performed with sufficient adhesion. Once the sprayed layer of the sprayed film is formed, when the sprayed film is successively laminated thereon, the surface of the sprayed layer is irradiated with a plasma jet and the raw material is supplied while melting the surface, so that the sprayed layer is formed. Can be improved in adhesion.
[0028]
The distance between the spray gun that irradiates the plasma jet onto the quartz glass substrate and the substrate varies depending on the apparatus used. For example, in the case of a normal plasma spray apparatus as shown in FIG. 1, the distance is between the quartz glass substrate and the tip of the spray gun. Examples of such conditions include a spraying distance of the powder supply port of about 50 mm and a spraying power of 35 kW or more. On the other hand, if the reduced pressure plasma spraying method is used, since the shape of the plasma jet becomes longer, it is possible to melt the surface of the quartz glass substrate even if the distance between the quartz glass substrate and the spray gun is 100 mm or more.
[0029]
Particularly when manufacturing large quartz glass parts, among plasma spraying methods, see a double torch type plasma spraying apparatus (Japanese Patent Publication No. 6-22719, thermal spraying technology Vol. 11, No. 1, p. 1 to 8 (1991), etc.). ) Is preferably used for thermal spraying with a laminar plasma jet. FIG. 2 shows an outline of a double torch type plasma spraying apparatus. In the double torch type plasma spraying apparatus, since a laminar flame plasma having a length of several hundred mm (usually about 50 mm in a turbulent state) can be formed, the sprayed film of the present invention can be formed even when the spray distance is 100 mm. .
[0030]
As the thermal spraying powder used in the case of plasma spraying, a fine powder of the above-mentioned element or a compound of the above-mentioned element is sprinkled and attached to quartz glass powder or quartz powder, and the above-mentioned element or the above-mentioned element is added to quartz glass fine powder or quartz fine powder. After mixing the compound fine powder with a ball mill or the like and sintering the granules obtained by the spray drying method, adding the compound containing the blackening element to quartz glass powder or quartz powder to form a bulk blackened glass, A crushed product or the like can be used.
[0031]
The average particle diameter of the sprayed powder is preferably 20 μm or more and 100 μm or less. If the average particle diameter is less than 20 μm, it is difficult to uniformly introduce the raw material into the plasma due to insufficient fluidity, and it is difficult to obtain a uniform sprayed film. If the average particle size exceeds 100 μm, it takes a long time to melt and tends to be non-uniform, and it is considered that the reducing gas is difficult to be taken into quartz glass. In addition, irregularities and spots are generated on the surface of the sprayed black quartz glass film, and the base material is easily deformed due to a reduced linear velocity of the spray gun.
[0032]
The method of spraying transparent or opaque quartz glass on the sprayed black quartz glass film and laminating it uses the same quartz glass powder or quartz powder as above but without adding a blackening element or a blackening element compound. Good. As the thermal spraying conditions, the same conditions as those for the above-mentioned black quartz glass may be used.However, in order to obtain opaque quartz glass, the spraying distance is increased, the moving speed of the spray gun is increased, the input power is reduced, and the like. Can be made opaque.
[0033]
When forming a sprayed black quartz glass film on a part of a quartz glass substrate, a step is formed on the quartz glass substrate, and a black quartz glass sprayed film is formed on a lower part to spray black quartz glass without steps. Parts can also be manufactured. As shown in FIG. 3, by forming a black quartz glass sprayed film and a transparent quartz glass sprayed film on the same surface of a quartz glass substrate, a black quartz glass sprayed part having no steps can be manufactured. Such a quartz glass part can be processed only by thermal spraying even on a curved surface where processing is troublesome, there is no need to process later
[0034]
【Example】
The present invention will be described in more detail based on examples, but the present invention is not limited to only these examples.
[0035]
Example 1
A black quartz glass sprayed film was formed on a transparent quartz glass substrate having a width of 40 mm, a length of 600 mm, and a thickness of 2 mm using a double torch type plasma spraying apparatus as shown in FIG. A pure argon gas was used as the plasma gas, the flow rate was 10 SLM, and a power of 23 kW was applied to generate a laminar plasma jet having a length of about 300 mm. The entire surface of the transparent quartz glass substrate was heated by moving the spraying gun at a speed of 100 mm / s from one end of the substrate to the other in the length direction with the spraying distance being 100 mm. The preheating temperature was set to 900 ° C. by performing heating twice over the entire surface.
[0036]
Next, the plasma gas was changed to a gas in which hydrogen gas was mixed with argon gas at 10%, and the sprayed powder was supplied to argon gas at a rate of 10 g / min to form a black sprayed film. The sprayed powder is obtained by crushing a black quartz glass material to which 0.8 wt% of niobium (Nb) is added, sieving so that the particle diameter is 30 μm or more and 65 μm or less, immersing in 10% hydrofluoric acid for 1 hour, and rinsing with pure water. And dried. The spraying distance was 100 mm, and a sprayed film was formed while melting the surface of the quartz glass substrate under the condition that the plasma jet frame touched the quartz glass substrate during the spraying of the raw material powder. Thermal spraying is performed by spraying a spraying gun at a rate of 100 mm / s onto the transparent quartz glass substrate from one end to the other in the longitudinal direction of the base material, and performing the spraying five times over the entire surface to obtain a 1 mm-thick black quartz. A glass sprayed film was obtained. The substrate temperature immediately after the thermal spraying was 1000 ° C. Since particles having insufficient adhesion were adhered to the surface of the sprayed film obtained on the surface of the sprayed film, the plasma was not supplied to the entire surface of the sprayed film once more without supplying the sprayed powder. Irradiated with a jet to produce a sprayed black quartz glass part having no particulate matter that easily peeled off on the surface.
[0037]
The resulting black quartz glass sprayed part had black color on the entire surface without color unevenness, and the light transmittance was measured in a wavelength range of 185 to 25000 nm. The transmittance at any wavelength was 0.5% or less. . No crystalline substance was observed by X-ray diffraction, and the substance was in a glassy state.
[0038]
Example 2
Using a transparent quartz glass substrate having a width of 150 mm, a length of 200 mm, and a thickness of 4 mm, a sprayed black quartz glass film was formed using a double torch type plasma spraying apparatus as shown in FIG. A pure argon gas was used as the plasma gas, the flow rate was 10 SLM, and a power of 23 kW was applied to generate a laminar plasma jet having a length of about 300 mm. The entire surface of the transparent quartz glass substrate was heated by moving the spraying gun at a speed of 100 mm / s from one end of the substrate to the other in the longitudinal direction with the spraying distance being 100 mm. The preheating temperature was set to 950 ° C. by performing heating twice over the entire surface.
[0039]
Next, the plasma gas was changed to a gas in which hydrogen gas was mixed with argon gas at 10%, and the sprayed powder was supplied to the argon gas at a rate of 10 g / min. The spraying gun was moved to the end at a speed of 100 mm / s to spray the transparent quartz glass substrate. Thermal spraying was performed seven times over the entire surface to obtain a sprayed black quartz glass film having a thickness of 1.4 mm. The sprayed powder is obtained by crushing a black quartz glass material to which 3 wt% of vanadium (V) is added, sieving so that the particle diameter is 30 μm or more and 65 μm or less, immersing in 10% hydrofluoric acid for 1 hour, and rinsing with pure water. And dried. The substrate temperature immediately after thermal spraying was 1050 ° C.
[0040]
Next, the sprayed powder was replaced with a high-purity quartz powder having an average particle size of 40 μm, and sprayed under the same conditions as the above-mentioned black quartz glass sprayed film. Finally, the spray gun was set at 100 mm / s without supplying the sprayed powder. By moving at a speed and irradiating the entire surface of the sprayed film surface with a plasma jet, a transparent quartz glass sprayed film (film thickness: 1 mm) having a smooth surface was laminated.
[0041]
The black quartz glass sprayed part obtained had black color on the entire surface without color unevenness, and the light transmittance was measured in a wavelength range of 185 to 25000 nm. As a result, the transmittance was almost zero at any wavelength. In addition, X-ray diffraction analysis confirmed that the sprayed black quartz glass film and the sprayed transparent quartz glass film were in a glassy state.
[0042]
Example 3
A transparent quartz glass tube having an outer diameter of 20 mm, a thickness of 1 mm, and a length of 550 mm is masked by a half quartz tube having an inner diameter of 20 mm and a black quartz glass sprayed film using a double torch type plasma spraying device. did. A pure argon gas was used as the plasma gas, the flow rate was 10 SLM, and a power of 23 kW was applied to generate a laminar plasma jet having a length of about 300 mm. The entire surface of the transparent quartz glass tube was heated by moving and rotating the spraying gun at a speed of 100 mm / s from one end of the transparent quartz glass tube to the other in the longitudinal direction with the spraying distance being 100 mm. The preheating temperature was set to 900 ° C. by performing heating twice over the entire surface.
[0043]
Next, the plasma gas was changed to a gas in which hydrogen gas was mixed with argon gas at 10%, and the sprayed powder was supplied to the argon gas at a rate of 10 g / min. The spray gun was moved and rotated at a speed of 100 mm / s until the sprayed film was formed only on the unmasked portion of the transparent quartz glass tube. By performing the thermal spraying five times, a sprayed black quartz glass film having a thickness of 1 mm was obtained. The thermal spray powder is obtained by crushing a black quartz glass material to which molybdenum (Mo) is added at 5 wt%, sieving so that the particle size is 30 μm to 65 μm, immersing in 10% hydrofluoric acid for 1 hour, and rinsing with pure water. And dried. The substrate temperature immediately after thermal spraying was 1050 ° C.
[0044]
Next, the sprayed powder was replaced with a high-purity quartz powder having an average particle size of 40 μm, the quartz tube used for the mask was removed, and the black quartz glass sprayed film forming portion was made of quartz having an inner diameter of 22 mm and a half of quartz. A transparent quartz glass sprayed film having a thickness of 1 mm was formed under the same conditions on the portion masked when forming the sprayed black quartz glass film by masking with a tube.
[0045]
Finally, by removing the mask of the quartz tube and irradiating the entire circumference with a plasma jet at a pitch of 20 degrees while oscillating the spray gun at a speed of 100 mm / s without supplying the spray powder, the sprayed black quartz glass film portion is formed. A quartz glass part having no step in the transparent quartz glass sprayed film portion was manufactured.
[0046]
The black quartz glass sprayed part obtained was black without color unevenness, and its light transmittance was measured in a wavelength range of 185 to 25000 nm. The transmittance was almost zero at any wavelength. When X-ray diffraction was examined, it was confirmed that both the sprayed black quartz glass film and the sprayed transparent quartz glass film were in a glass state.
[0047]
Example 4
An opaque quartz glass disk (OP-3 glass manufactured by Tosoh Quartz Co., Ltd.) having a diameter of 250 mm and a thickness of 2 mmt was used as a base material, and a black quartz glass sprayed film was formed using a double torch type plasma spraying apparatus as shown in FIG. An argon gas was used as the plasma gas, the flow rate was 10 SLM, and a power of 25 kW was applied to generate a laminar plasma jet having a length of about 300 mm. The spraying gun was moved at a speed of 120 mm / s while oscillating over a width of 350 mm at a spraying distance of 100 mm, and the entire surface of the opaque quartz glass substrate was heated. The preheating temperature was set to 850 ° C. by performing heating twice over the entire surface.
[0048]
Next, the plasma gas was changed to a gas in which methane gas was mixed with argon gas at 10%, the sprayed powder was mixed with argon gas at a rate of 10 g / min, the spray distance was set to 100 mm, and the spray gun was set to a width of 350 mm at a speed of 120 mm / s. It was moved while shaking, and spraying was performed 5 times over the entire surface to obtain a sprayed black quartz glass film having a thickness of 1 mm. The thermal spray powder is obtained by crushing a black quartz glass material to which 3 wt% of carbon (C) is added, sieving so that the particle diameter is 30 μm or more and 65 μm or less, immersing in 10% hydrofluoric acid for 1 hour, and rinsing with pure water. And dried. The substrate temperature immediately after spraying the black quartz glass was 1000 ° C.
[0049]
Next, the sprayed powder was exchanged for a high-purity quartz powder having an average particle diameter of 40 μm, and the plasma gas was changed to a mixture of argon gas and hydrogen gas at 10% to form a transparent quartz glass sprayed film on the black quartz glass sprayed film. did. The power, the amount of the sprayed powder, and the spraying distance were the same as those for the above-mentioned black quartz glass spraying, but the moving speed of the spraying gun was 200 mm / s. Repeated times. Finally, the spray gun was moved at a speed of 120 mm / s while swinging over a width of 350 mm without supplying the spray powder, and the entire surface of the sprayed film was irradiated with a plasma jet. The obtained quartz glass part is a quartz glass part having a sprayed layer of black quartz glass on an opaque quartz glass having a flat surface and a porosity of 30%, on which a sprayed film of opaque quartz glass is laminated. was gotten.
[0050]
The black quartz glass sprayed part obtained was black without color unevenness, and its light transmittance was measured in a wavelength range of 185 to 25000 nm. The transmittance was almost zero at any wavelength. When X-ray diffraction was examined, it was confirmed that both the sprayed black quartz glass film and the sprayed opaque quartz glass film were in a glass state.
[0051]
Comparative Example 1
A black quartz glass material to which 3 wt% of vanadium (V) is added is pulverized, sieved to have a particle size of 30 μm or more and 65 μm or less, and press-formed and laminated on a transparent quartz glass are vacuum evacuated. The mixture was heated and melted in a melting furnace to produce a quartz glass entirely black and a lump of quartz glass in which black quartz glass was laminated on transparent quartz glass. These lumps were cut and polished to obtain quartz glass parts.
[0052]
The quartz glass part of the present invention obtained in Examples 1 to 4, the above-described whole black quartz glass part, and the laminated quartz glass part were placed in an electric furnace and kept at 1200 ° C. in the atmosphere for three days. After cooling, the glass was taken out and observed, and no crystallization was observed by X-ray diffraction in the quartz glass parts of Examples 1 to 4. Further, in Examples 1 to 3, there was no visible devitrification in the transparent quartz glass portion and no crystallization, and no significant change was observed in the sprayed film of black quartz glass. Parts.
[0053]
On the other hand, in the laminated quartz glass component manufactured in the vacuum melting furnace, some devitrified portions were observed at the interface between the transparent quartz glass and the black quartz glass. In addition, spots were observed in some places in the black quartz glass as a whole, and oxidation of the compound added for blackening was observed.
[0054]
【The invention's effect】
The quartz glass component sprayed with black quartz glass and the method of manufacturing the same according to the present invention have the following effects.
(1) Since it is coated with black quartz glass, it has low light transmittance and excellent heat shielding properties.
(2) Unlike conventional fused black quartz glass, there is no deterioration due to crystallization when heat is applied.
(3) When a transparent or opaque quartz glass is sprayed on a black quartz glass, the problem of diffusion of impurities derived from the base material or the black quartz glass is particularly small.
(4) Quartz glass parts of various shapes can be easily manufactured.
[Brief description of the drawings]
FIG. 1 is an example of a plasma spraying apparatus for forming a sprayed black quartz glass film of the present invention.
FIG. 2 is another example of a plasma spraying apparatus for forming a sprayed black quartz glass film of the present invention.
FIG. 3 is an example of a black quartz glass sprayed part in which a black quartz glass sprayed film and a transparent quartz glass sprayed film of the present invention are formed on the same surface of a quartz glass substrate.
[Explanation of symbols]
10, 20: cathode
11, 21: Anode
12, 22: Plasma gas
13, 23: Powder supply port
14, 24: Spray distance
15, 25: base material
16, 26: Thermal spray coating
17, 28: DC power supply
18, 29: Plasma jet
27: Argon gas for cathode protection
30: quartz glass substrate
31: Sprayed coating of black quartz glass
32: Sprayed transparent quartz glass film

Claims (4)

A quartz glass part comprising a sprayed film of black quartz glass formed on a quartz glass substrate. The quartz glass part according to claim 1, wherein a transparent quartz glass sprayed film or an opaque quartz glass sprayed film is laminated on the blackened quartz glass sprayed film. 3. The black quartz glass sprayed film contains at least one element selected from the group consisting of Nb, V, Mo and C as a blackening element of quartz glass. Quartz glass parts as described. Using a plasma spray method using an inert gas or a mixed gas of an inert gas, a hydrogen gas and / or a hydrocarbon gas as a spray gas, while melting the surface of the quartz glass substrate or the sprayed film being formed by a plasma jet. The method for producing a sprayed black quartz glass part according to claim 1, wherein a sprayed black quartz glass film is formed.

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