Glass component and method for manufacturing same

Abstract

The present invention relates to a glass member for use in a semiconductor manufacturing apparatus, the glass member having a hydrogen content of 200 ppm by mass or less. Furthermore, the present invention relates to a method for manufacturing the glass member by heating and melting a glass raw material at a melting temperature of 1500-1800 DEG C, and cooling the obtained molten glass at a cooling rate of 100-1500 DEG C / min to a cooling stop temperature of 700-900 DEG C.

Description

TECHNICAL FIELD

[0001] The present application relates to a glass member and a method for manufacturing the same. BACKGROUND

[0002] Components for a semiconductor manufacturing apparatus are often exposed to plasma in the operation of the semiconductor manufacturing apparatus and gradually consumed. Components that have progressed to a certain degree of consumption are replaced with new parts.

[0003] In recent years, as products manufactured by a semiconductor manufacturing apparatus are increasingly high and complex, the plasma environment to which components are exposed becomes increasingly severe, in which case, components need to be frequently replaced.

[0004] However, the semiconductor manufacturing apparatus cannot be operated during replacement of components. Therefore, if the frequency of replacement of components increases, the production efficiency of products decreases.

[0005] Therefore, further longer life of components used in a semiconductor manufacturing apparatus is required. That is, good plasma resistance is required.

[0006] As a semiconductor manufacturing apparatus, for example, a plasma etching apparatus can be cited.

[0007] In a plasma etching apparatus, various components such as a ceiling plate (conductor type), a microwave introduction pipe, a lift pin, and various nozzles are used.

[0008] Conventionally, as these components, a material such as a cordierite sintered body is used (Patent Document 1).

[0009] PRIOR ART DOCUMENTS

[0010] PATENT DOCUMENTS

[0011] Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 9-295863 SUMMARY

[0012] A glass member is sometimes used in a semiconductor manufacturing apparatus. In this case, the glass member also needs to have good plasma resistance.

[0013] The present application was achieved in view of the above, and aims to provide a glass member for a semiconductor manufacturing apparatus, and excellent in plasma resistance.

[0014] The present inventors and others have conducted intensive studies, and as a result, have found that the above object can be achieved by adopting the following configuration, thereby completing the present application.

[0015] That is, the present application provides the following [1] to

[15] .

[0016] [1] A glass member for a semiconductor manufacturing apparatus, having a hydrogen content of 200 mass ppm or less.

[0017] [2] The glass member according to the above [1], wherein the average of the refractive index at a wavelength of 365 nm is 1.5 or more, and the difference between the upper limit value and the lower limit value is 0.2 or less.

[0018] [3] The glass member according to the above [1] or [2], wherein the Young's modulus is 100 GPa or more, and the average coefficient of thermal expansion at 50 to 350°C is 4 to 7 ppm / K. 2 the cross-sectional area.

[0019] [4] The glass member according to any one of the above [1] to [3], which is a ring having an outer diameter of 300 to 600 mm, an inner diameter of 200 to 450 mm, and a thickness of 2 to 30 mm, and has a chamfering process of C1.0 or less, a surface roughness Ra of 1 μm or less, and a flatness of 0.5 mm or less.

[0020] [5] The glass member according to any one of the above [1] to [4], wherein yttrium and silicon are contained, and the molar ratio Y / Si of the content of yttrium to the content of silicon is 0.2 to 1.5.

[0021] [6] The glass member according to any one of the above [1] to [5], wherein the content of SiO2 is 40 to 70 mol%, the content of Y2O3 is 5 to 40 mol%, and the content of Al2O3 is 10 to 30 mol%.

[0022] [7] The glass member according to the above [6], wherein the content of the oxide of element a selected from at least one of tantalum, boron, magnesium, calcium, strontium, and barium is 10 mol% or less.

[0023] [8] The glass member according to the above [6] or [7], wherein the content of the oxide of element b selected from at least one of an alkali metal element, iron, and titanium is 3000 mass ppm or less.

[0024] [9] The glass member according to any one of the above [1] to [8], wherein the Young's modulus is 100 GPa or more, and the average coefficient of thermal expansion at 50 to 350°C is 4 to 7 ppm / K.

[0025]

[10] The glass member according to any one of the above [1] to [9], wherein the transmittance at a wavelength of 800 nm is 92% or less.

[0026]

[11] The glass member according to any one of the above [1] to

[10] , wherein the surface roughness Ra is 0.1 mm 2 or less in any 10 regions of 100 mm 2The number of the bubbles above is 40 or less in total.

[0027]

[12] The glass member according to any one of the above [1] to

[11] , wherein the area ratio of the crystals is 5% or less on average in an area of 100 mm 2 0.1 mm 2 The area ratio of the crystals above is 5% or less on average.

[0028]

[13] The glass member according to any one of the above [1] to

[12] , which is used as a focus ring, a shower plate, an electrostatic chuck, a susceptor, an injector, a view window, a top plate, or a side wall of the semiconductor manufacturing apparatus.

[0029]

[14] The glass member according to any one of the above [1] to

[13] , wherein the etching rate relative to quartz when etching is performed using CF4 gas having a flow rate of 100 seem is 0.1 or less.

[0030]

[15] A method for manufacturing a glass member, which is the method for manufacturing the glass member according to any one of the above [1] to

[14] , wherein a glass raw material is heated to be molten at a melting temperature of 1500 to 1800°C, and the obtained molten glass is cooled at a cooling rate of 100 to 1500°C / min to a cooling stop temperature of 700 to 900°C.

[0031] According to the present application, it is possible to provide a glass member having excellent plasma resistance. DETAILED DESCRIPTION

[0032] A numerical range indicated using "~" means a range including the numerical values written before and after the "~" as lower limit values and upper limit values.

[0033] [GLASS MEMBER]

[0034] The glass member of the present embodiment is a glass member for a semiconductor manufacturing apparatus, and the content of hydrogen is 200 mass ppm or less.

[0035] Hereinafter, the glass member is simply referred to as "glass", and the glass member of the present embodiment is referred to as "the present glass member" or "the present glass".

[0036] The present glass member has excellent plasma resistance. The reason is presumed as follows.

[0037] First, the hydrogen contained in the glass member is considered to come from water molecules, and since the content thereof is small, the structure of the glass member is dense, and as a result, the speed of deterioration due to plasma irradiation is slow.

[0038] In addition, in the case where fluorine is contained in the plasma (or the gas used for generating the plasma), hydrogen contained in the glass member easily reacts with the fluorine, but since the hydrogen is small, the reaction with the fluorine is relatively reduced, and the damage to the glass member is suppressed.

[0039] 〈Content of hydrogen (H content)〉

[0040] In the present glass member, the content of hydrogen (also referred to as "H content") is 200 mass ppm or less as described above.

[0041] From the reason that the plasma resistance is more excellent, the H content is preferably 150 mass ppm or less, more preferably 100 mass ppm or less, further preferably 50 mass ppm or less, still further preferably 40 mass ppm or less, particularly preferably 30 mass ppm or less, very preferably 20 mass ppm or less, and most preferably 10 mass ppm or less.

[0042] On the other hand, from the practical value that is easy to control in view of mass productivity, the H content is, for example, 1 mass ppm or more, preferably 2 mass ppm or more, and more preferably 3 mass ppm or more.

[0043] The H content of the glass member is found by secondary ion mass spectrometry (SIMS).

[0044] More specifically, using a secondary ion mass spectrometry device (Model IMS-6f, manufactured by AMETEK Corporation), it is found under the conditions of a primary ion species Cs ＋ , a primary acceleration voltage of 15.0 kV, a detection area of φ 30 μm, and a measurement depth of 1 μm.

[0045] 〈Average refractive index〉

[0046] 《Average》

[0047] In the present glass member, the average of the refractive index at a wavelength of 365 nm (abbreviated as "refractive index") is preferably 1.5 or more, more preferably 1.57 or more, further preferably 1.63 or more, particularly preferably 1.68 or more, and most preferably 1.7 or more.

[0048] Thus, the plasma resistance of the present glass member is more excellent. The reason is presumed as follows. The plasma resistance of elements such as yttrium (Y) is good, and if such elements are more, the refractive index of the glass member is high.

[0049] On the other hand, the average of the refractive index is preferably 1.8 or less, more preferably 1.76 or less, and further preferably 1.73 or less.

[0050] In the case where the average of the refractive index is within the range, crystallization at the time of manufacturing the glass member is suppressed, and in addition, surface reflectance of the glass member is also suppressed, and therefore light of a sensor or the like is easily transmitted.

[0051] "Deviation" between the upper limit value and the lower limit value

[0052] In the present glass member, the "deviation" between the upper limit value and the lower limit value of the refractive index is preferably 0.2 or less, more preferably 0.05 or less, further preferably 0.01 or less, more further preferably 0.005 or less, particularly preferably 0.001 or less, very preferably 0.0005 or less, and most preferably 0.0003 or less.

[0053] Thus, the plasma resistance of the present glass member is more excellent. The reason is presumed to be that, in the case where the refractive index is not deviated and is uniformly high, a phenomenon in which only a part is easily damaged by plasma irradiation or the like does not easily occur, and the plasma resistance is good as a whole.

[0054] Note that, if the glass member is large-sized, the strength, the composition, or the like can be deviated depending on the site, and thus it is beneficial that the plasma resistance is good as a whole without deviation.

[0055] "Measuring method"

[0056] The refractive index of the glass member is measured at 10 arbitrary points using a Kalnew precision refractometer KPR-3000 (accuracy: ±0.00002 (23°C)). The average of the measured values at the 10 points is taken as the average of the refractive index. In addition, the "deviation" (deviation between the upper limit value and the lower limit value) between the upper limit value and the lower limit value of the measured values at the 10 points is calculated.

[0057] 〈Glass composition〉

[0058] Next, the composition (glass composition) of the present glass member is described. That is, the content of the elements that can be contained in the present glass member is described.

[0059] "Si, Y, and Al"

[0060] The present glass member can contain silicon (Si), yttrium (Y), and can further contain aluminum (Al).

[0061] (Molar ratio Y / Si)

[0062] The molar ratio (Y / Si) of the content of yttrium (Y) to the content of silicon (Si) is preferably 0.2 or more, more preferably 0.4 or more, and further preferably 0.5 or more. Thus, the glass member contains relatively more Y, and the plasma resistance is more excellent.

[0063] On the other hand, from the viewpoint of suppressing crystallization at the time of manufacturing the glass member, the molar ratio (Y / Si) is preferably 1.5 or less, more preferably 1.0 or less, and further preferably 0.8 or less.

[0064] (Content of SiO2)

[0065] The content of SiO2 is preferably 40 mol% or more, more preferably 45 mol% or more, and further preferably 50 mol% or more.

[0066] On the other hand, the content of SiO2 is, for example, 80 mol% or less, preferably 70 mol% or less, more preferably 65 mol% or less, and further preferably 60 mol% or less.

[0067] (Content of Y2O3)

[0068] The content of Y2O3 is preferably 5 mol% or more, more preferably 10 mol% or more, further preferably 15 mol% or more, and particularly preferably 20 mol% or more. Thereby, the refractive index of the glass member is increased, and the plasma resistance is more excellent.

[0069] On the other hand, the content of Y2O3 is preferably 40 mol% or less, more preferably 35 mol% or less, further preferably 30 mol% or less, and particularly preferably 25 mol% or less, from the viewpoint of suppressing crystallization at the time of manufacturing the glass member.

[0070] (Content of Al2O3)

[0071] The content of Al2O3 is preferably 10 mol% or more, more preferably 15 mol% or more, and further preferably 18 mol% or more, from the viewpoint of improving the strength and heat resistance of the glass member.

[0072] On the other hand, the content of Al2O3 is preferably 30 mol% or less, more preferably 28 mol% or less, and further preferably 25 mol% or less, from the viewpoint of obtaining more excellent plasma resistance.

[0073] "Element a: Ta, B, Mg, Ca, Sr, and Ba"

[0074] The present glass member can contain an element a selected from at least one of tantalum (Ta), boron (B), magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba).

[0075] However, the content of element a, converted from oxide, is preferably 10 mol% or less, more preferably 8 mol% or less, further preferably 5 mol% or less, even more preferably 3 mol% or less, particularly preferably 1 mol% or less, and most preferably 0 mol%. It should be noted that when the glass component contains multiple elements as element a, the "content of element a, converted from oxide," refers to the total content of the individual oxides of each of the multiple elements.

[0076] The Ta content converted from oxides specifically refers to the Ta2O5 content.

[0077] The B content in oxide conversion specifically refers to the B2O3 content.

[0078] The Mg content converted from oxides specifically refers to the MgO content.

[0079] The Ca content converted from oxides specifically refers to the CaO content.

[0080] The Sr content converted from oxides specifically refers to the SrO content.

[0081] The Ba content converted from oxides specifically refers to the BaO content.

[0082] Element b: Alkali metals, Fe and Ti

[0083] This glass component sometimes contains element b selected from at least one of alkali metals, iron (Fe), and titanium (Ti).

[0084] Examples of alkali metal elements include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). Among these, lithium (Li), sodium (Na), and potassium (K) are preferred.

[0085] However, element b is an impurity element for glass components used in semiconductor manufacturing apparatuses, and is preferably present in small quantities. Specifically, the content of element b as an oxide equivalent is preferably 3000 ppm by mass or less, more preferably 1000 ppm by mass or less, further preferably 300 ppm by mass or less, particularly preferably 100 ppm by mass or less, and most preferably 50 ppm by mass or less. It should be noted that when the glass component contains multiple elements as element b, the "content of element b as an oxide equivalent" refers to the total content of each of the multiple elements as an oxide equivalent.

[0086] The content of alkali metal elements (R) converted from oxides specifically refers to the content of R2O.

[0087] The Fe content converted from oxides specifically refers to the Fe2O3 content.

[0088] The content of Ti in terms of oxide is specifically the content of TiO2.

[0089] "Measurement method"

[0090] The content of each of the above elements (excluding Si) in the glass member (expressed in terms of mole percentage on an oxide basis or mass percentage) was measured using a fluorescent X-ray device (XRF) (ZSX100e manufactured by Rigaku Corporation). That is, the X-ray intensity of each element on the surface of the glass member was measured and quantitatively analyzed to obtain the content of each element.

[0091] The content of SiO2in the glass member was obtained as follows.

[0092] First, a powder sample was collected from the central portion of the glass member by grinding, and the total oxygen content Z1in the glass member was obtained using an oxygen-hydrogen analyzer (ROH-600 manufactured by LECO Corporation) by infrared absorption method.

[0093] The oxygen content Z2of the elements (excluding Si) contained in the glass member and combined in stoichiometric composition was subtracted from the total oxygen content Z1in the glass member to calculate the oxygen content Z3 (oxygen content Z3 = total oxygen content Z1- oxygen content Z2).

[0094] Assuming that the total amount of the oxygen content Z3 is used for combination with silicon atoms, the oxygen content Z3 was converted into the amount of SiO2. The amount of SiO2thus obtained was used as the content of SiO2in the glass member.

[0095] "YOUNG'S MODULUS"

[0096] The Young's modulus of the present glass member is preferably 60 GPa or greater, more preferably 80 GPa or greater, further preferably 100 GPa or greater, and particularly preferably 110 GPa or greater. Such a present glass member has good dimensional accuracy, is less likely to be deflected, and has excellent thermal shock resistance.

[0097] On the other hand, the upper limit of the Young's modulus of the present glass member is not particularly limited, and is, for example, 200 GPa, preferably 180 GPa, and more preferably 160 GPa.

[0098] The Young's modulus of the glass member was measured at 25°C using an ultrasonic pulse method.

[0099] "EXPANSION COEFFICIENT"

[0100] In a semiconductor manufacturing device, the glass member is sometimes used in combination with other members (also referred to as "peripheral members"), and as a material for the peripheral members, SiC, AlN, and the like can be given.

[0101] The coefficient of expansion of the glass member is preferably close to the coefficient of expansion of the material of the surrounding member. Thus, the behavior of expansion and contraction of the glass member tends to be in harmony with that of the surrounding member, thereby preventing detachment from the surrounding member or the like.

[0102] Specifically, the average coefficient of thermal expansion (hereinafter simply referred to as "coefficient of expansion") of the glass member at 50 to 350°C is preferably 4 ppm / K or more, more preferably 4.1 ppm / K or more, further preferably 4.2 ppm / K or more, particularly preferably 4.5 ppm / K or more.

[0103] On the other hand, the coefficient of expansion of the glass member is preferably 7 ppm / K or less, more preferably 6.5 ppm / K or less, further preferably 6 ppm / K or less.

[0104] The coefficient of expansion is measured using a differential thermal dilatometer according to the method described in JIS R 3102-1995.

[0105] <Transmittance>

[0106] The lower the transmittance of the glass member, the more excellent the heat insulation property. Thus, from the viewpoint of obtaining a good heat insulation property, the transmittance of the glass member at a wavelength of 800 nm (hereinafter simply referred to as "transmittance") is preferably 92% or less, more preferably 91% or less, further preferably 90% or less, still further preferably 89% or less, particularly preferably 88% or less.

[0107] However, the glass member is sometimes required to have a certain degree of transparency due to the use in a semiconductor manufacturing apparatus. Thus, from the viewpoint of ensuring a good transparency, the transmittance of the glass member is preferably 80% or more, more preferably 83% or more, further preferably 85% or more.

[0108] The transmittance is measured according to the method of JIS R 3106 (1998) on a glass member having a thickness of 2 mm. That is, the transmittance is a transmittance converted to a thickness of 2 mm.

[0109] <Number of Bubbles>

[0110] The glass member sometimes contains bubbles (air bubbles), but from the viewpoint of excellent appearance and more excellent plasma resistance, large bubbles are preferably small.

[0111] Specifically, the number of bubbles in any 10 100 mm 2 areas in the glass member is preferably 0.1 mm 2 The number of bubbles (hereinafter simply referred to as "number of bubbles") is preferably 40 or less in total, more preferably 30 or less, further preferably 20 or less, particularly preferably 10 or less, most preferably 5 or less.

[0112] More specifically, a glass member in a plate shape (thickness: 2 mm) was prepared, and a photograph was taken of an arbitrary region (area: 100 mm 2 square) on a main surface of the glass member using an optical microscope. The area ratio of bubbles having an area of 0.1 mm 2 or more in the region was measured from the photograph. The total of the number of bubbles in the regions of arbitrary 10 positions was calculated.

[0113] 〈Crystal ratio〉

[0114] In the glass member, sometimes crystals (crystalline phase) are contained. From the viewpoint of ensuring good transparency, it is preferable that large crystals be few. Also, from the viewpoint of reducing dust generated when the glass member is exposed to plasma, it is also preferable that large crystals be few.

[0115] More specifically, in an arbitrary 100 mm 2 square region in the glass member, the area ratio of crystals having an area of 0.1 mm 2 or more (also referred to as "crystal ratio" for convenience) was measured. The average of the crystal ratios in the regions of arbitrary 10 positions was calculated.

[0116] More specifically, a glass member in a plate shape (thickness: 2 mm) was prepared, and a photograph was taken of an arbitrary region (area: 100 mm 2 square) on a main surface of the glass member using an optical microscope. The area ratio of crystals having an area of 0.1 mm 2 or more (unit: %) was measured from the photograph. The average of the area ratios of crystals in the regions of arbitrary 10 positions was calculated.

[0117] <Etching rate>

[0118] In the present glass member, when a CF4 gas having a flow rate of 100 sccm is used, the etching rate of the present glass member with respect to quartz is preferably 0.1 or less, more preferably 0.05 or less, further preferably 0.04 or less, more further preferably 0.03 or less, and most preferably 0.02 or less. It can be said that the smaller the etching rate, the more excellent the plasma resistance of the present glass member, the longer the service life of the present glass member, and the less frequent the replacement, and the tact time of the manufacturing apparatus is improved. The lower limit of the etching rate is not particularly limited, and from the viewpoint of easy production of glass, it is preferably 0.01 or more.

[0119] The details of the calculation conditions of the etching rate in the present specification are as follows.

[0120] (Calculation conditions of etching rate)

[0121] A test piece of 20 mm x 20 mm x 2 mm in size was cut out from the glass member, and the surface of 20 mm x 20 mm was mirror-finished. A part of the mirror-finished surface was masked by sticking a Kapton tape, and etching was performed with a plasma gas under the following conditions.

[0122] • Apparatus: CCP-RIE

[0123] • Gas species: CF4 (100 sccm)

[0124] • Output: 350 W

[0125] • Pressure: 10 Pa

[0126] • Time: 130 minutes

[0127] • Temperature: 20°C

[0128] Then, the height difference generated between the etched portion and the non-etched portion was measured using a stylus-type surface shape measuring apparatus (Dectak 150, manufactured by ULVAC, Inc.), and thus the etching amount (abrasion amount) was calculated.

[0129] Further, the etching amount was also calculated for the quartz glass.

[0130] The ratio of the etching amount of the glass member to the etching amount of the quartz glass was calculated as the etching rate.

[0131] <Usage>

[0132] The glass member is used, for example, as a part or the whole of each portion provided in a semiconductor manufacturing apparatus (including a semiconductor inspection apparatus).

[0133] As each portion provided in the semiconductor manufacturing apparatus, for example, a focus ring, a shower plate, an electrostatic chuck, a susceptor, an injector (injector nozzle), a viewing window (a portion for observing the inside from the outside of the semiconductor manufacturing apparatus), a top plate, or a side wall (inner wall) can be given.

[0134] <Shape and size>

[0135] As the shape of the glass member, a plate shape (for example, a round plate shape, a flat plate shape), a spherical shape (a spherical shape, an ellipsoidal shape), a ring shape, and the like can be given, and is appropriately selected according to the usage.

[0136] The size of the glass member is appropriately selected according to the usage.

[0137] The glass member can be upsized according to the usage, and for example, can have a size of 10 cm 2The sectional area of the above (for example, the sectional area of the glass member in the case where the glass member is in the form of a plate, the sectional area being parallel to the main surface). From the viewpoint of general usability, the sectional area of the glass member is preferably 100 cm 2 More preferably, the sectional area is 300 cm 2 Further preferably, the sectional area is 500 cm 2 The sectional area of the above.

[0138] On the other hand, the upper limit of the sectional area is not particularly limited. However, from the viewpoint of general usability, the sectional area is preferably 5000 cm 2 More preferably, the sectional area is 1000 cm 2 Further preferably, the sectional area is 500 cm

[0139] In the case where the glass member is used for a focus ring, a pedestal, or the like, the shape thereof is ring-like.

[0140] From the reason that the glass member is suitable for use as a focus ring or the like, the outer diameter of the ring-like glass member is preferably 300 to 600 mm, more preferably 350 to 450 mm. From the same reason, the inner diameter is preferably 200 to 450 mm, more preferably 250 to 350 mm. From the same reason, the thickness is preferably 2 to 30 mm, more preferably 3 to 7 mm.

[0141] At this time, it is preferable to perform chamfering processing of C1.0 or less on the ring-like glass member.

[0142] In addition, from the viewpoint of suppressing dust at the time of irradiation of plasma and not being easily affected by thermal stress, the surface roughness (arithmetic average roughness Ra) of the ring-like glass member is preferably 1 μm or less, more preferably 0.1 μm or less, and further preferably 0.03 μm or less. Ra is measured in accordance with JIS B 0601:2001.

[0143] In addition, from the reason that the dimensional accuracy is good, the flatness of the ring-like glass member is preferably 0.5 mm or less, more preferably 0.1 mm or less, and further preferably 0.03 mm or less. The flatness can be measured by a non-contact three-dimensional shape measuring device (manufactured by Y-FA Systems Co., Ltd., NH-5Ns).

[0144] [Method for manufacturing glass member]

[0145] Next, a method for manufacturing the glass member (hereinafter, also referred to as "the present manufacturing method") will be described.

[0146] The present manufacturing method is, in brief, a method in which a glass raw material is heated to be molten, and the obtained molten glass is cooled.

[0147] 〈Glass raw material〉

[0148] The various glass raw materials are preferably weighed and mixed in such a manner that the composition of the resulting glass member becomes the above-described glass composition.

[0149] "Use of Oxides"

[0150] As the glass raw materials, oxides are preferably used instead of hydroxides. By doing so, the OH amount (H amount) of the glass raw materials decreases, so the H content of the resulting glass member easily decreases.

[0151] However, for the purpose of reducing the number of bubbles contained in the resulting glass member, a sulfur compound can also be added to the glass raw materials. As the sulfur compound, from the viewpoint of reducing the amount of impurities contained in the resulting glass member, for example, aluminum sulfate is preferable.

[0152] "Amount of Moisture"

[0153] From the reason that the H content of the resulting glass member easily decreases, the amount of moisture contained in the glass raw materials is preferably 200 mass ppm or less, more preferably 150 mass ppm or less, further preferably 100 mass ppm or less, still further preferably 50 mass ppm or less, particularly preferably 30 mass ppm or less, very preferably 25 mass ppm or less, and most preferably 20 mass ppm or less.

[0154] The amount of moisture of the glass raw materials can be adjusted by drying the glass raw materials or the like.

[0155] The amount of moisture of the glass raw materials is found by thermogravimetric analysis (TGA).

[0156] It has been confirmed.

[0157] "Mixing Conditions"

[0158] When the glass raw materials are mixed, it is preferable to use a stirrer to stir the glass raw materials at 10 to 100 rpm for 10 minutes or more. By doing so, the glass raw materials are sufficiently mixed, and the deviation of the refractive index of the resulting glass member easily decreases.

[0159] The glass raw materials can be put in a bag and mixed by shaking. At this time, it is preferable to shake 100 times or more. By doing so, the glass raw materials are sufficiently mixed, and the deviation of the refractive index of the resulting glass member easily decreases.

[0160] "Melt"

[0161] Next, the mixed glass raw materials are heated to be melted. At this time, the melt can be appropriately subjected to degassing, homogenization, or the like according to a publicly known method. By doing so, a molten glass is obtained.

[0162] "Type of Atmosphere Gas"

[0163] The atmosphere during melting of the glass raw material (also referred to as "melting atmosphere") is, for example, the atmosphere (atmospheric atmosphere).

[0164] A gas (also referred to as "atmosphere gas") can be introduced into the melting atmosphere.

[0165] As the atmosphere gas, nitrogen (N2), oxygen (O2), compressed air, water vapor (H2O), and the like can be given, and one of these can be used alone or two or more of these can be used in combination. When N2and O2are used in combination, the volume ratio of the two (N2 / O2) is, for example, 8 / 2.

[0166] Among these, at least one selected from N2, O2, and compressed air is preferred from the viewpoint of easily reducing the H content of the resulting glass member.

[0167] The atmosphere gas can be bubbled into the glass raw material (molten glass) or can simply flow over the surface of the vessel (crucible or the like) that contains the glass raw material.

[0168] "Flow rate of atmosphere gas"

[0169] The flow rate of the atmosphere gas SLM (flow rate per 1 minute at 1 atm, 0°C) is, for example, 0.1 L / min or more, preferably 1 L / min or more, more preferably 3 L / min or more, further preferably 5 L / min or more, still further preferably 10 L / min or more, particularly preferably 15 L / min or more, very preferably 20 L / min or more, and most preferably 25 L / min or more.

[0170] On the other hand, the flow rate of the atmosphere gas is preferably 60 L / min or less, more preferably 55 L / min or less, further preferably 50 L / min or less, particularly preferably 45 L / min or less, and most preferably 40 L / min or less.

[0171] "Temperature of atmosphere gas"

[0172] From the viewpoint of keeping the glass dissolution temperature constant, the temperature of the atmosphere gas is preferably 30°C or more, more preferably 35°C or more, and further preferably 40°C or more.

[0173] On the other hand, from the viewpoint of reducing manufacturing costs, the temperature of the atmosphere gas is preferably 100°C or less, more preferably 80°C or less, and further preferably 60°C or less.

[0174] "Melting temperature"

[0175] The temperature at which the glass raw material is heated and melted (melting temperature) is preferably 1500°C or higher, more preferably 1550°C or higher, and further preferably 1600°C or higher. Thus, the glass raw material is sufficiently melted, and the variation in the refractive index of the resulting glass member is easily reduced.

[0176] On the other hand, from the viewpoint of manufacturing cost, the melting temperature is preferably 1800°C or lower, more preferably 1750°C or lower, and further preferably 1700°C or lower.

[0177] "Melting time"

[0178] The time at which the glass raw material is heated and melted (melting time) is preferably 2 hours or more, more preferably 2.5 hours or more, and further preferably 3 hours or more. Thus, the glass raw material is sufficiently melted, and the variation in the refractive index of the resulting glass member is easily reduced. In addition, since the molten glass is sufficiently clarified, the number of bubbles contained in the resulting glass member is easily reduced.

[0179] On the other hand, from the viewpoint of excellent manufacturing cost, the melting time is preferably 24 hours or less, more preferably 12 hours or less, further preferably 10 hours or less, more further preferably 8 hours or less, particularly preferably 6 hours or less, and most preferably 4 hours or less.

[0180] "Stirring"

[0181] When the glass raw material is heated and melted, it is preferable to stir the glass raw material using a stirrer at 20 to 60 rpm for 1 hour or more. Thus, the glass raw material is sufficiently melted, and the variation in the refractive index of the resulting glass member is easily reduced.

[0182] "Water quenching and remelting"

[0183] The resulting molten glass can be subjected to water quenching one or more times, and then remelted. Thus, the variation in the refractive index of the resulting glass member is easily reduced.

[0184] "cooling"

[0185] Then, the resulting molten glass is cooled.

[0186] At this time, it is preferable to cool (rapidly cool) the molten glass from the above-mentioned melting temperature to the below-mentioned cooling stop temperature. Then, it is appropriately cooled to room temperature (for example, 25°C).

[0187] "cooling stop temperature"

[0188] The cooling stop temperature is, for example, 700 to 900°C, and is preferably 750 to 850°C.

[0189] "cooling rate"

[0190] From the viewpoint of reducing the crystals contained in the obtained glass member, the cooling rate from the melting temperature to the cooling stop temperature is preferably 100°C / min or more, more preferably 200°C / min or more.

[0191] On the other hand, from the viewpoint of suppressing the deviation of the glass composition in the obtained glass member and the viewpoint of easy control in the production of the glass member, the cooling rate is preferably 1500°C / min or less, more preferably 1000°C / min or less, further preferably 800°C / min or less, particularly preferably 500°C / min or less.

[0192] It should be noted that if the cooling rate is in the above range, the deviation of the glass composition caused by the thermal convection at the time of casting is suppressed, and the deviation of the refractive index of the obtained glass member is easily reduced.

[0193] <Shaping>

[0194] The molten glass is preferably cooled after being shaped into a desired shape.

[0195] As the shaping method, there is no particular limitation, and for example, a float method, a press method, a fusion method, a down-draw method, and the like can be given. It should be noted that the obtained molten glass can be cooled after being shaped into a temporary shape, and the obtained temporary body can be subjected to processing such as cutting.

[0196] <Slow cooling>

[0197] In order to remove the strain in the glass, the shaped glass can be subjected to slow cooling.

[0198] At this time, for example, the glass is held at an arbitrary temperature for a certain period of time, and then cooled to room temperature (for example, 25°C).

[0199] From the reason that the strain can be removed efficiently, the temperature at which the glass is held (holding temperature) is preferably a temperature in the vicinity of the glass transition point, and specifically, for example, 700 to 1100°C, more preferably 850 to 950°C.

[0200] The time for which the glass is held at the holding temperature (holding time) is, for example, 1 to 10 hours, preferably 2 to 5 hours. The larger and more complex the shape of the glass is, the longer the holding time is preferably.

[0201] The cooling rate from the holding temperature to room temperature is, for example, 0.1 to 5°C / min, preferably 0.5 to 1°C / min.

[0202] By this, a glass member of a desired shape can be obtained. To the obtained glass member, processing such as grinding, polishing, and the like can be performed as needed.

[0203] <logη at the time of casting>

[0204] The viscosity log η of the molten glass at the time of casting is preferably 0.5 Pa s or more for cooling or the like. This is to suppress deviation in the glass composition caused by thermal convection at the time of casting, thereby reducing deviation in the refractive index of the resulting glass member.

[0205] Example

[0206] Hereinafter, the present application will be specifically described by citing examples. However, the present application is not limited to the examples described below.

[0207] [Experiment A: Examples Al to Al l]

[0208] Hereinafter, Examples Al to AlO are examples, and Example Al l is a comparative example.

[0209] The glass raw materials were weighed and mixed in such a manner that the glass composition of the resulting glass member was SiO2: 59 mol%, Y2O3: 22 mol%, and Al2O3: 19 mol%. The water content of the glass raw materials is shown in Table 1 below.

[0210] The mixed glass raw materials were put into a platinum crucible and introduced into an electric furnace, and were melted at a melting temperature of 1600°C (melting time: 3 hours) by heating to obtain a molten glass.

[0211] The atmosphere gas was introduced into the melting atmosphere under the conditions shown in Table 1 below.

[0212] Herein, in the case where the glass was melted directly under an atmosphere of air without introducing the atmosphere gas, it is indicated as "air" in Table 1 below.

[0213] Further, in the case where nitrogen (N2) and oxygen (O2) were used together in a volume ratio of 8 / 2 (N2 / O2), it is indicated as "N2+O2" in Table 1 below.

[0214] The resulting molten glass was cooled from the melting temperature to a cooling stop temperature of 800°C at a cooling rate of 250°C / min, and then further cooled to room temperature (25°C) to obtain a glass member (size: 100 mm x 100 mm x 15 mm).

[0215] The H content and the content of the elements b (Na, Fe, and Ti) in the resulting glass member are shown in Table 1 below.

[0216] 〈Etching rate〉

[0217] A test piece having a size of 20 mm x 20 mm x 2 mm was cut out from the glass member, and the face of 20 mm x 20 mm was mirror finished. A portion of the mirror finished face was shielded by pasting a Kapton tape, and etching was performed with a plasma gas under the following conditions.

[0218] Device: CCP-RIE

[0219] Gas species: CF4 (100 sccm)

[0220] Output: 350 W

[0221] Pressure: 10 Pa

[0222] Time: 130 minutes

[0223] Temperature: 20°C

[0224] Then, the height difference generated between the etched portion and the non-etched portion was measured using a stylus-type surface shape measuring device (Dectak 150, manufactured by ULVAC, Inc.), and thus the etching amount (wear amount) was calculated.

[0225] Further, the etching amount was also calculated for the quartz glass.

[0226] The ratio of the etching amount of the glass member with respect to the etching amount of the quartz glass was calculated as the etching rate. The results are shown in Table 1 below.

[0227] The smaller the value of the etching rate, the more excellent the plasma resistance can be evaluated.

[0228]

[0229] Summary of Evaluation Results

[0230] As shown in Table 1 above, the glass members of Examples Al to A10 having an H content of 200 mass ppm or less had a smaller value of the etching rate and good plasma resistance as compared with the glass member of Example Al 1 having an H content exceeding 200 mass ppm.

[0231] [Experiment B: Examples Bl to Bll]

[0232] Examples Bl to Bll are described below.

[0233] The glass raw materials were weighed so as to have the composition of Table 2 below, and otherwise, the same as Example A3 of Experiment A was performed to obtain a glass member.

[0234] Here, the cooling rate from the melting temperature to the cooling stop temperature was set to the rate shown in Table 2 below.

[0235] The H content, the average of the refractive index, the deviation of the refractive index, the Young's modulus, the expansion coefficient, the transmittance, the number of bubbles, the crystal ratio, and the etching rate of the obtained glass member are shown in Table 2 below.

[0236]

[0237] Summary of evaluation results

[0238] As shown in Table 2 above, the glass parts of Examples B1 to B11 having an H content of 200 mass ppm or less were excellent in plasma resistance.

[0239] [Experiment C: Examples C1 to C20]

[0240] Hereinafter, Examples C1 to C20 are examples of embodiments.

[0241] The glass raw materials were weighed so as to have the compositions shown in Table 3 below, and otherwise, the same as Example A3 of Experiment A was performed to obtain the glass parts shown in Table 3 below in terms of size. For the obtained glass parts, the surface was processed so as to have a surface roughness (Ra) and flatness shown in Table 3 below.

[0242] Here, the melting time was set to the temperature shown in Table 3 below. In addition, the cooling rate from the melting temperature to the cooling stop temperature was set to the rate shown in Table 3 below.

[0243] The H content, average of refractive index, deviation of refractive index, Young's modulus, coefficient of expansion, transmittance, number of bubbles, crystal ratio, and etching rate of the obtained glass parts are shown in Table 3 below.

[0244]

[0245] Summary of evaluation results

[0246] As shown in Table 3 above, the glass parts of Examples C1 to C20 having an H content of 200 mass ppm or less were excellent in plasma resistance.

[0247] The above describes various embodiments, but the present application is of course not limited to these examples. Obviously, those skilled in the art can conceive various modifications or corrections within the scope described in the patent application, and these certainly also belong to the scope of the technical range of the present application. In addition, the respective constituent elements in the above embodiments can also be arbitrarily combined within the scope of the gist of the present application.

[0248] Note that this application is based on Japanese Patent Application (2023-068600) filed on April 19, 2023, the content of which is incorporated herein by reference in its entirety.

Claims

1. A glass component for use in a semiconductor manufacturing apparatus, wherein the hydrogen content is less than 200 ppm by mass.

2. The glass component according to claim 1, wherein, The average refractive index at a wavelength of 365 nm is above 1.5, and the difference between the upper and lower limits is below 0.

2.

3. The glass component according to claim 1, having a 10cm diameter. 2 The above refers to the cross-sectional area.

4. The glass component according to claim 1 is an annular shape with an outer diameter of 300-600 mm, an inner diameter of 200-450 mm, and a thickness of 2-30 mm, and is subjected to chamfering with a C1.0 or less, a surface roughness Ra of less than 1 μm, and a flatness of less than 0.5 mm.

5. The glass component according to claim 1, wherein, It contains yttrium and silicon, with a molar ratio of yttrium to silicon of 0.2 to 1.

5.

6. The glass component according to claim 1, wherein, The content of SiO2 is 40-70 mol%, the content of Y2O3 is 5-40 mol%, and the content of Al2O3 is 10-30 mol.

7. The glass component according to claim 6, wherein, The content of the oxide of element a, selected from at least one of tantalum, boron, magnesium, calcium, strontium and barium, is less than 10 mol%.

8. The glass component according to claim 6, wherein, The content of the oxide of element b, selected from at least one of the alkali metals, iron and titanium, is less than 3000 ppm by mass.

9. The glass component according to claim 1, wherein, It has a Young's modulus of over 100 GPa and an average coefficient of thermal expansion of 4 to 7 ppm / K at 50 to 350 °C.

10. The glass component according to claim 1, wherein, The transmittance at a wavelength of 800nm ​​is below 92%.

11. The glass component according to claim 1, wherein, In any 10 100mm 2 Area, 0.1mm 2 The total number of bubbles is less than 40.

12. The glass component according to claim 1, wherein, In any 10 100mm 2 Area, 0.1mm 2 The area ratio of the above crystals is on average less than 5%.

13. The glass component according to claim 1, which is used as a focusing ring, spray plate, electrostatic chuck, base, ejector, observation window, top plate or sidewall of the semiconductor manufacturing apparatus.

14. The glass component according to claim 1, wherein, The etching rate when using CF4 gas at a flow rate of 100 sccm is less than 0.1 relative to quartz.

15. A method for manufacturing a glass component, comprising the method for manufacturing the glass component according to any one of claims 1 to 14. The glass raw material is heated to a melting temperature of 1500–1800°C to melt it, and the resulting molten glass is cooled to a cooling stop temperature of 700–900°C at a cooling rate of 100–1500°C / min.

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