• 专利附录
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    • 专利摘要:
    Pyrogenic oxides having a BET surface area of 30 to 150 m 2 / g have a viscosity of less than 2500 mPas in aqueous suspension. It is prepared by setting the hydrogen ratio gamma and oxygen ratio lambda to less than 1 in high-temperature flame hydrolysis. Pyrogenic oxides are used for CMP applications in the electronics industry.
    公开号:KR19980070733A
    申请号:KR1019980001974
    申请日:1998-01-23
    公开日:1998-10-26
    发明作者:만골트헬무트；플람벡-피셔피어；파울리잉고；얀존칼하인쯔
    申请人:메르크볼프강；데구사아크티엔게젤샤프트；
    IPC主号:
    专利说明:

    Pyrogenic oxides and methods for preparing the same
    The present invention relates to pyrogenic oxides, methods for their preparation and their use as polishing agents.
    It is known to produce pyrogenic silicon dioxide and also other metal or metalloid oxides by high temperature flame hydrolysis (Ullmann's Enzyklopadie der Technischen Chemie [Ullmann's Encyclopaedia of Industrial Chemistry] 4th edition, volume 21 pages 464 et seq.). have.
    In this process, metals and / or metalloid halogen compounds, such as silicon halogen compounds or organosilicon halogen compounds, are mixed and combusted with (air) oxygen and hydrogen in a burner of known design. The exothermic silicic acid formed is then removed from the gas containing hydrochloric acid and the chloride still attached to the oxide is removed by treatment with air containing water vapor.
    Known oxides have the disadvantage that their polishing performance is too low when used for CMP polishing.
    Therefore, it is an object of the present invention to develop an oxide made with exothermicity with improved polishing performance.
    1 shows an open mode of operation in which the reaction mixture is combusted in a reaction chamber which is open to the atmosphere and where pressure is predominant.
    2 shows a closed operating mode in which the reaction mixture is combusted in a closed reaction chamber from the atmosphere.
    3 shows the relationship of the relative removal rate of material during polishing as a function of flame parameter gamma and lambda.
    Figure 4 shows the relationship of the removal rate of the material to the fractality.
    The present invention provides a method for producing a pyrogenic oxide by a high temperature flame hydrolysis method wherein the hot flame hydrolysis method has a hydrogen ratio gamma (of the raw gas mixture in the central tube) of less than 1 during the production of the pyrogenic oxide. , Particularly preferably 0.7 to 0.9, and at the same time an oxygen vi lambda (of the feed gas mixture in the central tube) is also less than 1, particularly preferably 0.7 to 0.9, and gamma is characterized by stoichiometrically Hydrogen input is the ratio of hydrogen from the feedstock and lambda is the ratio of input oxygen to stoichiometrically necessary oxygen.
    The invention also relates to a pyrogenic metal oxide or metalloid oxide, preferably silicon dioxide, produced by the process according to the invention, wherein the process is characterized by the fact that hydrogen ratio gamma (of the feed gas mixture in the central tube) Less than 1, particularly preferably 0.7 to 0.9, and at the same time an oxygen ratio lambda (of the feed gas mixture in the central tube) is less than 1, particularly preferably 0.7 to 0.9.
    The invention also provides a pyrogenic silicon dioxide produced by the process according to the invention, which has a BET surface area of 30 to 150 m 2 / g of silicon dioxide and a viscosity of 2,500 mPas of a 19% aqueous suspension prepared from pyrogenic oxide Less than, preferably less than 1,000 Pas.
    The invention also provides pyrogenic silicon dioxide produced by the process according to the invention, which has a BET surface area of 30-150 m 2 / g of silicon dioxide and is described in Pfeifer, Obert and Cole, Proc. R. Soc. London, A 423, 169 (1989)], the fractional BET dimension determined by N 2 adsorption in the pressure range p / p 0 = 0.5 to 0.8 according to the fractal BET theory for multilayer absorption. dimension) is less than 2.605.
    Pyrogenic oxides typically react with chlorine (from a silicon halogen compound) in which the gaseous starting material is present in the raw material or hydrogen supplied externally to the combustible gas mixture is present in the combustible gas mixture to provide HCl gas. Provided by a method that is stoichiometrically proportionate to each other to be sufficient. The amount of hydrogen required for this is called the stoichiometric amount of hydrogen.
    The ratio of the hydrogen (external hydrogen + hydrogen chemically bound from the raw material) supplied to the burner to the stoichiometrically necessary hydrogen defined above is called gamma (γ). therefore:
    γ = the amount of hydrogen / stoichiometrically needed hydrogen supplied to the burner
    or
    Gamma = H 2 (mol) supplied / stoichiometric H 2 (mol)
    An amount of oxygen (eg from air) sufficient to convert at least the silicon compound to silicon dioxide and convert any excess hydrogen still present is further used in the preparation of the exothermic oxide.
    This amount of oxygen is called the stoichiometric amount of oxygen.
    Similarly, the ratio of oxygen supplied to the burner to the stoichiometrically necessary oxygen is called lambda (λ). therefore:
    λ = the amount of oxygen / stoichiometrically needed oxygen supplied to the burner
    or
    Lambda = supplied O 2 (mol) / stoichiometric O 2 (mol).
    The following example is intended to illustrate the use of the terms gamma and lambda.
    1 kg of SiCl 4 is burned with 0.5 Nm 3 of hydrogen and 3 Nm 3 of air.
    The basic scheme is:
    SiCl 4 + 2H 2 + O 2 ⇒ SiO 2 + 4HCl
    Thus, 2 mol of hydrogen and 1 mol of oxygen are required per 4 mol of SiCl.
    If 1 kg (5.88 mol) of SiCl 4 is required, the stoichiometric hydrogen requirement is 2 x 5.88 mol = 0.263 Nm 3 hydrogen.
    When 1 kg of SiCl 4 is burned with 0.5 Nm 3 of hydrogen, the calculated gamma is 0.5 / 0.263 = 1.9.
    The stoichiometric oxygen demand consists of two parts, in particular the part necessary to form silicon dioxide and the second part which converts excess hydrogen into water.
    Thus the stoichiometric oxygen requirement for this example is calculated as follows:
    Quantity a): Formation of SiO 2 = 5.88 mol = 0.131 Nm 3 (O 2 )
    Amount b): Formation of water from the amount of hydrogen not reacted with SiCl 4 (in Nm 3: H 2 + 1/2 O 2 ⇒ H 2 O, depending on the amount of 0.237 / 2 = 0.118Nm 3 oxygen 0.5-0.263 = 0.237 N㎥ of unreacted hydrogen)
    Stoichiometric oxygen demand = volume a) + volume b) = 0.131 + 0.118 = 0.249 Nm 3 (O 2 )
    When air 3Nm 3 (oxygen content corresponds to 21.0% by volume, thus oxygen of 0.63Nm 3 N) is used, the parameter lambda is measured as follows.
    Lambda = 0.63 / (0.131 + 0.118) = 2.53
    For raw materials which already contain hydrogen in the molecule, for example trichlorosilane, the hydrogen contained in the molecule is included in the calculation as additionally supplied hydrogen.
    For molecules containing carbon in the molecule, when calculating the stoichiometric oxygen demand, it must be taken into account that this carbon must react completely to produce CO 2 .
    There is a difference between an open mode of operation and a closed mode of operation for the production of pyrogenic oxides.
    In an open mode of operation, the reaction mixture is combusted in a reaction chamber that is open to the atmosphere and predominantly under reduced pressure, and ambient air is also drawn into the reaction chamber (FIG. 1).
    The gas mixture of raw materials is premixed homogeneously in a burner of known design and burned in the reaction chamber. To avoid caking, a second annular outflow nozzle through which (jacket) hydrogen outflows is placed around the annular outflow nozzle through which the raw material mixture exits.
    By definition, in the subsequent discussion and calculation of the flame parameters only the premixed stream portion in the central tube is taken into account. This means, for example, that the expression below stoichiometric relates to the ratio in the center tube only, not to the ratio in the reaction chamber.
    In the closed operating mode (FIG. 2), the reaction mixture is combusted in a closed reaction chamber from the atmosphere. In this mode of operation, generally, an accurately measured amount of secondary air is added to avoid the formation of explosive mixtures.
    In the normal operation of reactants to produce pyrogenic oxides, in both open and closed modes of operation, the gamma value exceeds 1 (to avoid the formation of chlorine) and the lambda value exceeds 1 (explosive mixture). To avoid this).
    When aqueous dispersions are prepared from pyrogenic oxides, according to the invention, during the CMP use of these dispersions, the removal rate of the material obtained (for the same specific surface area of the pyrogenic silicon dioxide used) is decisively determined in the preparation of pyrogenic oxides. It was found that it depends on the parameters of gamma and lambda.
    In particular, it has been found that increased removal rates of materials by polishing are achieved during the production of pyrogenic oxides when the gamma value is less than 1 and the lambda value is less than 1.
    Oxides prepared according to the invention show a marked increase in the removal rate of the material during CMP use compared to known oxides having the same specific surface area without deterioration of surface roughness.
    This is described in more detail with the following examples.
    All following examples are performed using the open mode of operation (FIG. 1).
    The measuring method of polishing rate and the manufacturing method of 12% dispersion liquid are as follows.
    Polishing rate is measured with a dispersion of 12% for pyrogenic oxides. The preparation of the dispersion and the precise measurement of the removal rate of the material are described in 1a in the practice of page 6 of WO 95/06690. The polishing rate of the 12% dispersion prepared from the exothermic silicic acid of Example 3 is defined as standard and set to 1.
    Since the removal rate is measured only for a very long time after the preparation of the pyrogenic silicic acid, a 19% aqueous dispersion is prepared for rapid characterization of the pyrogenic silicic acid. This 19% dispersion is used to monitor plant equipment and characterize silicic acid.
    A 12% dispersion is prepared as follows: 38 g exothermic oxide and 162 g deionized water are stirred with a dissolver at 2,500 rpm for 5 minutes. Viscosity is measured on a Brookfield viscometer DV 2 (axis size 2) at 5 rpm. The viscosity value is measured after 1 minute.
    Example 1: (low removal rate of material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 84% silicon tetrachloride and about 16% trichlorosilane by evaporating, the vapor having air 1325 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 360Nm 3 / said Genie a h, hydrogen about 90.4 vol%, nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B of known design so as to have a 177 Nm 3 / h burner containing methane 3.4% by volume of Mix in the stomach. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 85 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. Calculating the flame parameter gamma is 1.02 and the flame parameter lambda is 0.9.
    A 12% aqueous dispersion was prepared from the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.86.
    Example 2 (low removal rate of material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 84% silicon tetrachloride and about 16% trichlorosilane by evaporation, the vapor having air 1285 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 385Nm 3 / said Genie h to about 90.4 vol% hydrogen, and nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B 180Nm 3 / h containing methane 3.4% by volume of the burner in a known designed so as to have Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 85 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is calculated to be 1.01 and the flame parameter lambda is 0.88.
    A 12% aqueous dispersion was prepared with the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.86.
    Example 3 (Good Removal Rate of Material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 96% silicon tetrachloride and about 4% trichlorosilane by evaporation, the vapor having air 1100 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 281Nm 3 / said Genie h to about 90.4 vol% hydrogen, and nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B 229Nm 3 / h containing methane 3.4% by volume of the burner in a known designed so as to have Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 82 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is 0.92, and the flame parameter lambda is 0.77.
    A 12% aqueous dispersion was prepared from the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is one.
    Example 4 (Good Removal Rate of Material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 96% silicon tetrachloride and about 4% trichlorosilane by evaporation, the vapor having air 1100 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 260Nm 3 / said Genie h to about 90.4 vol% hydrogen, and nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B 260Nm 3 / h containing methane 3.4% by volume of the burner in a known designed so as to have Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is determined by the BET method. This is 81 m 2 / g.
    Calculate the flame parameters of the blended winch in the center tube. The flame parameter gamma is 0.94 and the flame parameter lambda is 0.77.
    A 12% aqueous dispersion was prepared from the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.99.
    Example 5 (Good Removal Rate of Material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 96% silicon tetrachloride and about 4% trichlorosilane by evaporation, the vapor having air of 1175 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 260Nm 3 / said Genie h to about 90.4 vol% hydrogen, and nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B 260Nm 3 / h containing methane 3.4% by volume of the burner in a known designed so as to have Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 90 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is 0.94 and the flame parameter lambda is 0.82.
    A 12% aqueous dispersion was prepared from the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.98.
    Example 6: (Good Removal Rate of Material)
    1900 kg / h of a raw material mixture comprising about 84% silicon tetrachloride and about 16% trichlorosilane was evaporated with 100 kg / h of propyltrichlorosilane, and the vapor was evacuated to about 94% by volume of hydrogen with air 1400 Nm 3 / h and Gas mixture A containing about 6% by volume trichlorosilane A 330 Nm 3 / h and gas mixture B containing about 90.4% hydrogen, 5.6% nitrogen, 0.6% carbon monoxide and 3.4% methane B 150Nm 3 / h Mix in a known burner designed to have. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 86 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is 0.92 and the flame parameter lambda is 0.89.
    A 12% aqueous dispersion was prepared from the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.95.
    Example 7: (Good Removal Rate of Material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 96% silicon tetrachloride and about 4% trichlorosilane by evaporation, the vapor having air 1125 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane gas mixture a 350Nm 3 / said Genie h to about 90.4 vol% hydrogen, and nitrogen 5.6% by volume, carbon monoxide, 0.6% by volume and the gas mixture B 250Nm 3 / h containing methane 3.4% by volume of the burner in a known designed so as to have Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 84 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is calculated to be 1.03 and the flame parameter lambda is 0.78.
    A 12% aqueous dispersion was prepared with the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 0.88.
    Example 8 (Good Removal Rate of Material)
    Evaporating 2000 kg / h of a raw material mixture comprising about 84% silicon tetrachloride and about 16% trichlorosilane by evaporation, the vapor having air 1125 Nm 3 / h and containing about 94% hydrogen and about 6% trichlorosilane Gas mixture A 320Nm 3 / h in a known burner designed to have a gas mixture B 125Nm 3 / h containing about 90.4% hydrogen, 5.6% nitrogen, 0.6% carbon monoxide and 3.4% methane. Mix. The gas mixture is combusted, the exothermic silicic acid formed is separated from the gas, treated with water vapor (for deoxidation), and the specific surface area is measured by the BET method. This is 85 m 2 / g.
    Calculate the flame parameters of the mixed stock in the center tube. The flame parameter gamma is 0.82 and the flame parameter lambda is 0.79.
    A 12% aqueous dispersion was prepared with the silicic acid thus prepared and a polishing experiment was carried out for polishing the silicon dioxide layer.
    The relative wear rate of the dispersion during polishing is 1.04.
    Reference data of the described experiments are summarized in Table 1.
    The dependence of the relative removal rate of the material during polishing is shown in FIG. 3 as a function of flame parameter gamma and lambda.
    It can be seen that the highest removal rate of material by the dispersion is obtained when the flame parameter is clearly at or below the value 1, preferably between 0.9 and 0.7, during the production of the pyrogenic oxide.
    Different removal rates of materials also demonstrate the different viscosity itself of aqueous suspensions prepared from pyrogenic oxides.
    In Table 1, there is a reverse relationship between the viscosity of the aqueous suspension and the material removal rate.
    The pyrogenic silicic acid prepared by the process according to the invention with reduced fractal dimension was compared to the pyrogenic siloxane produced by the known method. Decreasing fractional dimensions increases the removal rate of the increased material.
    Fractional dimensions are calculated by the N 2 adsorption method in the pressure range p / p o in the range from 0.5 to 0.8. The results of the measurements are described in the Pfiefer, Obert and Cole method [Proc. R. Soc. London, A 423, 169 (1989)] according to the fractal BET theory for multilayer adsorption.
    The dependence of the removal rate of the material on the fractionality is shown in FIG. 4. The figure further shows a 95% confidence curve in addition to a regression line.
    Example NumberRaw materialPTSAir coreMixture AMixture BGamma CoreLambdacoreRemoval rateBETViscosity 19% /Fractal DimensionFlow rate [kg / h][kg / h][Nm 3 / h][Nm 3 / h][Nm 3 / h][-][-][Arbitrary unit][m 2 / g][mPas] One2000 / R1013253601771.020.90.8685 2.607 22000 / R1012853851801.010.880.8685 32000 / R2011002812290.920.77One824002.581 42000 / R2011002602600.940.770.9981 52000 / R2011752602600.940.820.9890 2.592 61900 / R110014003301500.920.890.958610582.601 72000 / R2011253502501.030.780.8884 82000 / R1011253201250.820.791.0485522.584
    R 1 = Raw material 1 = 16 wt% trichlorosilane, 84 wt% silicon tetrachloride
    R 2 = Raw Material 2 = 4 wt% trichlorosilane, 96% wt silicon tetrachloride
    PTS = Propyltrichlorosilane
    Mixture A = see above
    Mixture B = see above
    Gamma core: hydrogen ratio in the center tube
    Lambda core: oxygen ratio in the center tube
    Removal rate of the substance according to Example 3 (it is 1 by definition)
    The exothermic oxide of the present invention has a formed polishing performance.
    权利要求:
    Claims (6)
    [1" claim-type="Currently amended] Hydrogen ratio gamma (of the feed gas mixture in the center tube) during the production of the pyrogenic oxide (where gamma is the ratio of the hydrogen supplied in addition to the hydrogen from the feed to the stoichiometrically needed hydrogen from the feed) Is less than 1, particularly preferably 0.7 to 0.9, while at the same time oxygen ratio lambda (of the feed gas mixture in the center tube), where lambda is the ratio of the oxygen supplied to the stoichiometrically needed oxygen. Less than 1, particularly preferably 0.7 to 0.9, characterized in that the pyrogenic oxide by high temperature flame hydrolysis method.
    [2" claim-type="Currently amended] The exothermicity produced by the process according to claim 1 characterized in that during the production the hydrogen ratio gamma is less than 1, particularly preferably 0.7 to 0.9, while the oxygen ratio is also less than 1, particularly preferably 0.7 to 0.9. Metal oxides or metalloid oxides, preferably silicon dioxide.
    [3" claim-type="Currently amended] The exotherm produced by the process according to claim 1, characterized in that the BET surface area of silicon dioxide is 30 to 150 m 2 / g and the viscosity of the 19% aqueous suspension made from pyrogenic oxide is less than 2500 mPas, preferably less than 1000 mPas. Sung silicon dioxide.
    [4" claim-type="Currently amended] Silicon dioxide has a surface area of 30 to 150 m 2 / g and is described by Pfiefer, Obert and Cole (Proc. R. Soc. London, A 423, 169 (1989)). According to the fractal BET theory for multilayer adsorption, the first aspect characterized in that the fractional BET dimension measured by the N 2 adsorption method in the range of 0.5 to 0.8 in the pressure range p / p o is less than 2.605. Pyrogenic silicon dioxide prepared by the method according to claim.
    [5" claim-type="Currently amended] Use of a pyrogenic oxide produced by the method according to claim 1 as a raw material for producing a dispersion for use in a CMP product.
    [6" claim-type="Currently amended] Use of a pyrogenic oxide produced by the method according to claim 1 as a raw material for producing a dispersion used for polishing a product in the electronics industry.
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    同族专利:
    公开号 | 公开日
    KR100444415B1|2004-11-06|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    1997-01-23|Priority to DE19702230
    1997-01-23|Priority to DE19702230.8
    1998-01-23|Application filed by 메르크볼프강, 데구사아크티엔게젤샤프트
    1998-10-26|Publication of KR19980070733A
    2004-11-06|Application granted
    2004-11-06|Publication of KR100444415B1
    优先权:
    申请号 | 申请日 | 专利标题
    DE19702230|1997-01-23|
    DE19702230.8|1997-01-23|
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