Ceramic arm and its preparation method and application

Abstract

The present invention provides a ceramic arm and a preparation method and application thereof, and relates to the technical field of ceramic arms. The preparation method of the ceramic arm directly uses a first mold and a second mold to hot-press out a first body and a second body, and then covers the first body and the second body and hot-presses them to form a closed airway. This method does not require the use of an adhesive for bonding, thus avoiding the defects caused by the aging of the adhesive. At the same time, it also avoids the problems of uneven airways, cracking and dark cracks caused by degreasing of the mold core caused by the use of an airway model; the present invention also provides a ceramic arm, which is made by the preparation method of the ceramic arm. The obtained ceramic arm has high strength, and the airway surface formed is flat and smooth, with high precision and small error, uniform airway flow, and a long service life.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic arms and relates to a ceramic arm and a preparation method and application thereof. Background Art

[0002] The current ceramic arm mainly relies on a combination of ceramic plates to form an airway, and the ceramic plates are usually fixed by organic or inorganic adhesives. However, as the use time of the ceramic arm increases, the adhesive will age, causing the airtightness of the ceramic arm airway to deteriorate, thereby shortening the service life. In addition, the above-mentioned adhesives are greatly affected by temperature. Organic adhesives are generally used below 300°C, and high-temperature inorganic adhesives are generally used below 800°C. If the use temperature exceeds the above-mentioned temperature of the above-mentioned organic adhesive or inorganic adhesive, air leakage is inevitable, thereby affecting the normal use of the ceramic arm.

[0003] In order to avoid the influence of the binder on the ceramic arm, the prior art also proposes a method for preparing a ceramic arm, specifically, the ceramic raw material and the airway model made of a low melting point material (such as paraffin) are co-formed, and the airway model is directly pressed inside to obtain a green body with an airway model; then the airway model is burned, and the green body with the airway model removed is sintered to obtain a ceramic arm with an airway. Compared with the ceramic arm formed by the combination of ceramic plates, the ceramic arm prepared by this preparation method does not need to be bonded and fixed, and there will be no problem of airway leakage in the future. However, it is found in practice that powder particles will stick to the airway model of this method, the airway will be uneven during the pressing process, and there will be pits on the airway wall, which makes it difficult to clean the arm, and there is a phenomenon that dust particles will stick to the airway during sintering, resulting in product pollution and affecting use.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In view of the shortcomings and defects of the prior art, the present invention aims to provide a method for preparing a ceramic arm. The method directly utilizes a first mold and a second mold to hot-press the airways of a first body and a second body, and then covers the first body and the second body and hot-presses them to form a closed airway. The method does not require the use of an adhesive for bonding, thus avoiding the defects caused by aging of the adhesive. At the same time, it also avoids the problems of uneven airways, cracking and dark cracks caused by degreasing of the model, etc. caused by the use of an airway model.

[0006] In order to achieve the above purpose, the following technical solutions are adopted:

[0007] The present invention provides a method for preparing a ceramic arm, comprising the following steps:

[0008] (a) providing a granulated powder formed by ceramic powder and an additive;

[0009] Providing a first mold and a second mold for forming a ceramic arm to be prepared, wherein one of the first mold and the second mold has the same airway structure as the ceramic arm to be prepared;

[0010] (b) adding granulated powder into a first mold and a second mold respectively, then heating and pressurizing both molds, and demolding after cooling to obtain a first green body and a second green body, wherein one of the first green body and the second green body has the air channel structure;

[0011] (c) covering the first blank with the second blank, and then performing heating and pressurizing treatment to bond the first blank with the second blank, thereby obtaining an arm blank with a closed airway structure;

[0012] (d) Degreasing and sintering the arm blank to obtain a ceramic arm.

[0013] Furthermore, based on the above technical solution of the present invention, in step (a), the ceramic powder includes at least one of high-purity alumina powder, alumina antistatic composite ceramic powder, zirconium oxide antistatic composite ceramic powder or silicon carbide composite ceramic powder.

[0014] Further, based on the above technical solution of the present invention, in step (a), the auxiliary agent includes at least two of a plasticizer, a flux, a lubricant or a coupling agent;

[0015] Preferably, the plasticizer includes at least one of polypropylene, dibutyl phthalate or polyvinyl butyral;

[0016] Preferably, the flux comprises paraffin and / or polyethylene glycol;

[0017] Preferably, the lubricant comprises at least one of stearic acid, octadecyl alcohol or polyethylene wax;

[0018] Preferably, the coupling agent comprises aluminate and / or titanate.

[0019] Further, based on the above technical solution of the present invention, in step (a), the method for preparing the granulated powder comprises the following steps:

[0020] The ceramic powder and the additive are mixed and kneaded at high temperature, the kneaded material is cooled and solidified, and then crushed to obtain granulated powder;

[0021] Preferably, the high temperature kneading temperature is 160-220° C., and the time is 2-6 hours.

[0022] Further, based on the above technical solution of the present invention, in step (b), the heating temperature is 140-190° C.;

[0023] And / or, the pressurized pressure is 5-30 MPa, and the pressure is maintained for 5-10 minutes.

[0024] Further, based on the above technical solution of the present invention, in step (c), the heating temperature is 120-160° C.;

[0025] And / or, the pressurizing pressure is 3-50 MPa, and the pressure is maintained for 3-10 minutes.

[0026] Further, based on the above technical solution of the present invention, in step (d), the degreasing includes first performing solvent degreasing and then performing powder embedding degreasing;

[0027] Preferably, the solvent used for solvent degreasing includes at least one of deionized water, acetone, petroleum ether, kerosene or heptane;

[0028] Preferably, the temperature of solvent degreasing is 40-50°C and the time of solvent degreasing is 6-36h;

[0029] Preferably, the embedding powder used for embedding powder degreasing comprises aluminum oxide;

[0030] Preferably, the temperature for degreasing the buried powder is 400-600° C., and the temperature for degreasing the buried powder is 40-60 hours.

[0031] Further, based on the above technical solution of the present invention, in step (d), the sintering temperature is 1300-1700°C, the time required to heat up to the sintering temperature is 75-85h, and the time of keeping at the sintering temperature is 5-15h.

[0032] The present invention also provides a ceramic arm, which is prepared by using the above-mentioned preparation method of the ceramic arm.

[0033] The present invention also provides application of the ceramic arm in the field of semiconductor chip wafer handling equipment.

[0034] Compared with the prior art, the technical solution of the present invention has at least the following technical effects:

[0035] (1) The present invention provides a method for preparing a ceramic arm, wherein granulated powder formed by ceramic powder and an auxiliary agent are respectively added into a first mold and a second mold, and then heated and pressurized. After cooling, the molds are demolded to obtain a first body and a second body, and then the above bodies are covered and heated and pressurized to bond the first body and the second body to obtain an arm body with a closed airway structure. Finally, the arm body is degreased and sintered to obtain a ceramic arm. The preparation method directly uses the first mold and the second mold to hot-press the first body and the second body, and then covers the first body and the second body and hot-presses to form a closed airway. The method does not require the use of an adhesive for bonding, thereby avoiding the defects caused by aging of the adhesive. At the same time, it also avoids the problems of uneven airway, cracking and dark cracks caused by degreasing of the mold core caused by the use of an airway model. The ceramic arm prepared by the preparation method has high strength, a smooth airway surface, high precision, small error, uniform airway flow, and a long service life.

[0036] (2) The present invention also provides a ceramic arm, which is prepared by the ceramic arm preparation method. In view of the advantages of the above preparation method, the prepared ceramic arm has high strength, the formed airway surface is flat and smooth, the precision is high, the error is small, the airway flow is uniform, and it has a long service life.

[0037] (3) The present invention also provides an application of the above-mentioned ceramic arm. In view of the advantages of the above-mentioned ceramic arm, it has a good application prospect in the field of semiconductor chip wafer handling equipment. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. The process parameters of the following embodiments that do not specify specific conditions are usually based on conventional conditions.

[0039] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in the present invention.

[0040] According to a first aspect of the present invention, there is provided a method for preparing a ceramic arm, comprising the following steps:

[0041] (a) providing a granulated powder formed by ceramic powder and an additive;

[0042] Providing a first mold and a second mold for forming a ceramic arm to be prepared, wherein one of the first mold and the second mold has the same airway structure as the ceramic arm to be prepared;

[0043] (b) adding granulated powder into a first mold and a second mold respectively, then heating and pressurizing both molds, and demolding after cooling to obtain a first green body and a second green body, wherein one of the first green body and the second green body has the air channel structure;

[0044] (c) covering the first blank with the second blank, and then performing heating and pressurizing treatment to bond the first blank with the second blank, thereby obtaining an arm blank with a closed airway structure;

[0045] (d) Degreasing and sintering the arm blank to obtain a ceramic arm.

[0046] Specifically, in step (a), the ceramic powder can be made of a single type of ceramic raw material or a composite of different types of ceramic raw materials. The addition of additives helps to ensure that the green body has a certain strength and toughness, and ensures that the glue preparation temperature is different to achieve step-by-step degreasing, thereby avoiding cracking of the green body caused by concentrated degreasing at a single temperature.

[0047] As the forming mold for the ceramic arm to be prepared, the first mold and the second mold can be used to produce two green bodies, and the structure of the two green bodies after covering is the same as the structure of the ceramic arm to be prepared.

[0048] Step (b) and step (c) are the molding process of the ceramic arm to be prepared.

[0049] Among them, in step (b), after the granulation powder is added to the first mold and the second mold, the two molds are heated to melt the granulation powder, and then pressurized for pressure pressing. After the pressurization is completed, the temperature is lowered, the first mold is demolded to obtain a first green body, and the second mold is demolded to obtain a second green body.

[0050] In step (c), the first green body and the second green body have the same structure as the ceramic arm to be prepared after being covered. Different from the bonding method of the prior art using a binder, the first green body and the second green body are no longer bonded with a binder, but the first green body and the second green body after being covered are heated and pressurized. Under a certain temperature and pressure, the first green body and the second green body are slightly melted and bonded together, so that the airway structure on the first green body and the second green body is closed, and an arm green body is obtained.

[0051] In step (d), since some organic additives still remain in the arm blank, the arm blank needs to be degreased and sintered to obtain a ceramic arm.

[0052] The present invention provides a method for preparing a ceramic arm, wherein granulated powder formed by ceramic powder and an auxiliary agent is respectively added into a first mold and a second mold, and then heated and pressurized, and demolded after cooling to obtain a first green body and a second green body, and then the green bodies are covered and heated and pressurized to bond the first green body and the second green body to obtain an arm green body with a closed airway structure, and finally the arm green body is degreased and sintered to obtain a ceramic arm; the preparation method directly uses the first mold and the second mold to hot-press the airway of the first green body or the second green body, and then the first green body and the second green body are covered and hot-pressed to form a closed airway, the method does not need to use an adhesive for bonding, thus avoiding the defects caused by aging of the adhesive, and at the same time, it also avoids the problems of uneven airway, cracking and dark cracks caused by degreasing of the model caused by the use of an airway model, and the ceramic arm prepared by the preparation method has high strength, a smooth and flat airway surface, high precision, small error, uniform airway flow, and a long service life.

[0053] There is further optimization for the types of ceramic powders.

[0054] As an optional embodiment of the present invention, in step (a), the ceramic powder includes at least one of high-purity alumina powder, alumina antistatic composite ceramic powder, zirconium oxide antistatic composite ceramic powder or silicon carbide composite ceramic powder.

[0055] In the present invention, high-purity alumina powder refers to alumina powder with a purity greater than or equal to 99.8%.

[0056] Alumina antistatic composite ceramic powder or zirconium oxide antistatic composite ceramic powder is used as the raw material of the ceramic arm, which can make the ceramic arm itself have good and long-term antistatic performance, improving the problem that the antistatic coating on the surface of the ceramic arm in the prior art is easy to age and wear, resulting in a decrease in antistatic performance.

[0057] As an optional embodiment of the present invention, the alumina antistatic composite ceramic powder includes the following raw materials by mass fraction:

[0058] Alumina 65-95%, titanium dioxide 3-30%, silicon dioxide 0.2-1.5%, sintering aid 0.2-3%, tin oxide 0-5% and nickel oxide 0-1%; wherein the sintering aid includes at least one of yttrium oxide, calcium oxide, niobium oxide or cerium oxide.

[0059] The typical but non-limiting mass fraction of aluminum oxide is 65%, 68%, 70%, 75%, 78%, 80%, 85%, 88%, 90% or 95%; the typical but non-limiting mass fraction of titanium dioxide is 3%, 5%, 10%, 12%, 15%, 20%, 22%, 25%, 28% or 30%; the typical but non-limiting mass fraction of silicon dioxide is 0.2%, 0.5%, 1.0% or 1.5%; the typical but non-limiting mass fraction of sintering aid is The typical but non-limiting mass fraction of tin oxide is 0%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% or 3.0%; the typical but non-limiting mass fraction of tin oxide is 0%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% or 5.0%; the typical but non-limiting mass fraction of nickel oxide is 0%, 0.2%, 0.5%, 0.8% or 1.0%.

[0060] As an optional embodiment of the present invention, the zirconium oxide antistatic composite ceramic powder includes the following raw materials by mass fraction:

[0061] Cerium yttrium stabilized zirconium oxide 10-90%, aluminum oxide 1-5%, zinc oxide 5-85%, nickel oxide 0.05-5%, titanium dioxide 0.02-5%, silicon dioxide 0.1-5%, calcium oxide 0.02-5% and strontium oxide 0.1-3%.

[0062] Cerium-yttrium-stabilized zirconia refers to cerium oxide and yttrium oxide stabilized zirconia, the mass proportion of cerium oxide and yttrium oxide in zirconia is not specifically limited, the typical but non-limiting mass fraction of cerium-yttrium-stabilized zirconia is 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%; the typical but non-limiting mass fraction of aluminum oxide is 1.0%, 1.5%, 2.0%, 2.5%, 3 .0%, 3.5%, 4.0%, 4.5% or 5.0%; typical but non-limiting mass fractions of zinc oxide are 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 85%; typical but non-limiting mass fractions of nickel monoxide are 0.05%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0 %, 4.5% or 5.0%; typical but non-limiting mass fractions of titanium dioxide are 0.02%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% or 5.0%; typical but non-limiting mass fractions of silicon dioxide are 0.1%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% or 5.0%. %, 4.0%, 4.5% or 5.0%; typical but non-limiting mass fractions of calcium oxide are 0.02%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% or 5.0%; typical but non-limiting mass fractions of strontium oxide are 0.1%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% or 3.0%.

[0063] As an optional embodiment of the present invention, the silicon carbide composite ceramic powder includes the following raw materials in mass fraction:

[0064] Silicon carbide 90-99.5%, yttrium oxide 0.1-1%, calcium fluoride 0.1-1.5%, boron carbide 0.1-5.5% and aluminum oxide 0.2-2%.

[0065] Typical but non-limiting mass fractions of silicon carbide are 90%, 92%, 94%, 95%, 96%, 98%, 99% or 99.5%, typical but non-limiting mass fractions of yttrium oxide are 0.1%, 0.2%, 0.5%, 0.6%, 0.8% or 1.0%, typical but non-limiting mass fractions of calcium fluoride are 0.1%, 0.2%, 0.5%, 0.6%, 0.8%, 1.0%, 1.2% or 1.5%, typical but non-limiting mass fractions of boron carbide are 0.1%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0% or 5.5%; typical but non-limiting mass fractions of aluminum oxide are 0.2%, 0.5%, 1.0%, 1.5% or 2.0%.

[0066] As an optional embodiment of the present invention, in step (a), the auxiliary agent includes at least two of a plasticizer, a flux, a lubricant or a coupling agent, preferably a plasticizer, a flux, a lubricant and a coupling agent.

[0067] The plasticizer is mainly used to improve the strength of the blank. As an optional embodiment of the present invention, the plasticizer includes at least one of polypropylene, polyethylene, dibutyl phthalate or polyvinyl butyral.

[0068] Preferably, the mass of the plasticizer accounts for 0.3-10% (e.g., 0.3%, 0.5%, 1.0%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, 7.0%, 8.0%, 9.0% or 10.0%) of the mass of the ceramic powder.

[0069] As an optional embodiment of the present invention, the flux includes paraffin and / or polyethylene glycol, preferably paraffin and polyethylene glycol. Paraffin is used as a low-temperature flux, and polyethylene glycol is used as a high-temperature flux. The combination of the two can achieve debinding and degreasing at different temperatures and with different fluxes.

[0070] Preferably, the mass of the flux accounts for 2-8% (eg, 2%, 3%, 4%, 5%, 6%, 7% or 8%) of the mass of the ceramic powder.

[0071] The lubricant can improve the lubricity of the ceramic powder. As an optional embodiment of the present invention, the lubricant includes at least one of stearic acid, octadecyl alcohol or polyethylene wax.

[0072] Preferably, the mass of the lubricant accounts for 0.1-1.5% (e.g., 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.2%, 1.4% or 1.5%) of the mass of the ceramic powder.

[0073] The coupling agent can improve the fluidity of the ceramic powder and the flux. As an optional embodiment of the present invention, the coupling agent includes aluminate and / or titanate.

[0074] Preferably, the mass of the coupling agent accounts for 0.1-1% (eg, 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8% or 1%) of the mass of the ceramic powder.

[0075] As an optional embodiment of the present invention, in step (a), the method for preparing the granulated powder comprises the following steps:

[0076] The ceramic powder and the additive are mixed and kneaded at high temperature, the kneaded material is cooled and solidified, and then crushed to obtain granulated powder.

[0077] As an optional embodiment of the present invention, the high temperature kneading temperature is 160-220°C, and the time is 2-6 hours. Typical but non-limiting high temperature kneading temperatures are 160°C, 170°C, 180°C, 190°C, 200°C, 210°C or 220°C, and typical but non-limiting high temperature kneading times are 2 hours, 3 hours, 4 hours, 5 hours or 6 hours.

[0078] As an optional embodiment of the present invention, in step (b), the heating temperature is 140-190°C; and / or the pressurizing pressure is 5-30MPa, and the holding time is 5-10min. Typical but non-limiting heating temperatures are 140°C, 150°C, 160°C, 170°C, 180°C or 190°C; typical but non-limiting heating pressures are 5MPa, 6MPa, 8MPa, 10MPa, 15MPa, 18MPa, 20MPa, 22MPa, 25MPa, 28MPa or 30MPa; typical but non-limiting holding time is 5min, 6min, 8min, 9min or 10min.

[0079] As an optional embodiment of the present invention, in step (c), the heating temperature is 120-160°C; and / or, the pressurized pressure is 3-50MPa, and the holding time is 3-10min. Typical but non-limiting heating temperatures are 120°C, 130°C, 140°C, 150°C or 160°C; typical but non-limiting heating pressures are 3MPa, 5MPa, 10MPa, 15MPa, 18MPa, 20MPa, 22MPa, 25MPa, 28MPa, 30MPa, 32MPa, 35MPa, 40MPa, 42MPa, 45MPa or 50MPa; typical but non-limiting holding time is 3min, 4min, 5min, 6min, 8min, or 10min.

[0080] As an optional embodiment of the present invention, in step (d), degreasing includes first performing solvent degreasing and then performing embedded powder degreasing. First, the green body is soaked in a solvent (such as kerosene or heptane) to remove part of the paraffin and stearic acid, and then the embedded powder degreasing is performed to remove PEG at low temperature, 200-500°C to remove the remaining organic matter, so as to avoid concentrated decomposition of the organic matter, which causes volume expansion and cracking of the green body.

[0081] As an optional embodiment of the present invention, the solvent used for solvent degreasing includes at least one of deionized water, acetone, petroleum ether, kerosene or heptane.

[0082] As an optional embodiment of the present invention, the temperature of solvent degreasing is 40-50°C, and the time of solvent degreasing is 6-36h; a typical but non-limiting temperature of solvent degreasing is 40°C, 42°C, 44°C, 45°C, 48°C or 50°C; a typical but non-limiting time of solvent degreasing is 6h, 10h, 12h, 18h, 24h, 28h, 32h or 36h.

[0083] As an optional embodiment of the present invention, the embedding powder used for embedding powder degreasing includes aluminum oxide embedding powder.

[0084] As an optional embodiment of the present invention, the temperature of buried powder degreasing is 400-600°C, and the temperature of buried powder degreasing is 40-60h. Typical but non-limiting buried powder degreasing temperatures are 400°C, 420°C, 440°C, 450°C, 480°C, 500°C, 520°C, 540°C, 550°C, 580°C or 600°C; typical but non-limiting solvent degreasing time is 40h, 42h, 45h, 48h, 50h, 52h, 55h, 58h or 60h.

[0085] As an optional embodiment of the present invention, in step (d), the sintering temperature is 1300-1700°C, the time required to heat up to the sintering temperature is 75-85h, and the time of keeping at the sintering temperature is 5-15h. Typical but non-limiting sintering temperatures are 1300°C, 1350°C, 1400°C, 1550°C, 1500°C, 1550°C, 1600°C, 1650°C or 1700°C, and the time required to heat up to the sintering temperature is 75h, 78h, 80h, 82h or 85h. The sintering time required at the sintering temperature (1300-1700°C) is, for example, 5h, 6h, 8h, 10h, 12h or 15h.

[0086] As an optional embodiment of the present invention, after the sintering in step (d), the method further includes a step of fine processing the sintered product to obtain a ceramic arm.

[0087] Finishing includes steps such as grinding and polishing.

[0088] According to a second aspect of the present invention, there is also provided a ceramic arm, which is prepared using the above-mentioned method for preparing the ceramic arm.

[0089] In view of the advantages of the above preparation method, the ceramic arm has high strength, the formed airway surface is flat and smooth, the precision is high, the error is small, the airway flow is uniform and not easy to leak, and it has a long service life.

[0090] According to the third aspect of the present invention, there is also provided application of the above-mentioned ceramic arm in the field of semiconductor chip wafer handling equipment.

[0091] In view of the advantages of the above-mentioned ceramic arm, it has good application prospects in the field of semiconductor chip wafer handling equipment.

[0092] The present invention will be further described in detail below with reference to specific embodiments and comparative examples.

[0093] Example 1

[0094] This embodiment provides a method for preparing a ceramic arm, comprising the following steps:

[0095] (a) providing a granulated powder formed by ceramic powder (high-purity alumina powder) and an additive;

[0096] Mix and melt 83.5% of high-purity alumina powder (purity 99.8%) and 16.5% of additives (including 5% paraffin (PW), 8% polyethylene (PE), 2% polyethylene glycol (PEG), 1% stearic acid and 0.5% aluminate), put them in a mixer and stir them evenly, heat to 200°C to melt the additives, and knead and shear them evenly with the high-purity alumina powder at a speed of 160 rpm for 4 hours. Take out the evenly mixed material in a heated state, put it in a container and cool and solidify it. Use a jaw crusher to crush the solidified material into a mixture, sieve it to make the particles below 4 mesh, and obtain granulated powder.

[0097] A first mold and a second mold for forming a ceramic arm to be prepared are provided, wherein the first mold has the same airway structure as the ceramic arm to be prepared.

[0098] (b) Add granulated powder into a first mold and a second mold respectively, and then heat the first mold and the second mold at a heating temperature of 190°C for 15 minutes to make the granulated powder melt evenly, and pressurize the mold at a pressure of 8 MPa for 5 minutes after pressing, and cool the mold to 100°C before demolding to obtain a first green body and a second green body with an airway structure.

[0099] (c) Cover the first blank and the second blank (stack together), then put them into a mold, heat and pressurize them to bond the first blank and the second blank. The heating temperature is 150°C and the pressure is 3 MPa. After pressing, the pressure is maintained for 10 minutes. After cooling, the blank is demolded to obtain an arm blank with a closed airway structure.

[0100] (d) The arm blank was immersed in n-heptane for degreasing at a degreasing temperature of 50°C for 9 hours to remove part of PW and PEG, and then the blank was taken out and placed in an alumina crucible, and alumina embedding powder (particle size of 3-5 μm) was added, and heated to 60°C → 120°C → 200°C → 260°C → 330°C → 600°C, and each temperature point was kept warm for 5 hours. The total degreasing time was 60 hours (including the heating time and the holding time at each temperature point) to remove the remaining PW, PEG, PE, stearic acid and aluminate;

[0101] The degreased arm blank is placed in a sintering furnace and sintered, and the temperature is raised to 1620°C. The time taken to raise the temperature to the sintering temperature is 80 hours, and the temperature is kept at 1620°C for 6 hours. The sintered product is processed and subjected to wire cutting flat grinding, peripheral grinding, CNC processing, and polishing to obtain a ceramic arm.

[0102] Example 2

[0103] This embodiment provides a method for preparing a ceramic arm. Except that the ceramic powder in step (a) is replaced by zirconium oxide antistatic composite ceramic powder instead of high-purity alumina powder, the remaining steps and process parameters are the same as those in Example 1.

[0104] Zirconia antistatic composite ceramic powder includes the following components in mass fraction:

[0105] Cerium-yttrium-stabilized zirconium oxide 81%, zinc oxide 14%, aluminum oxide 1.5%, silicon dioxide 1%, titanium dioxide 1.5%, calcium oxide 0.5%, strontium oxide 0.2% and nickel monoxide 0.3%.

[0106] The method for preparing zirconium oxide antistatic composite ceramic powder comprises the following steps:

[0107] (1) Weigh cerium-yttrium-stabilized zirconium oxide, zinc oxide, aluminum oxide, silicon dioxide, titanium dioxide, calcium oxide, strontium oxide and nickel oxide in proportion and put them into a ball mill, then add zirconium oxide grinding balls, deionized water and dispersant (ammonium citrate, accounting for 0.3% of the weight of zirconium oxide antistatic composite ceramic powder), the material: ball: water mass ratio is 1:3:0.9, the ball mill is milled for 60 hours, the speed is 360r / min, and then a binder (brand PB-72, accounting for 0.5% of the weight of zirconium oxide antistatic composite ceramic powder) is added to the ball milled material, and the ball milling mixing is continued for 4 hours, and the slurry is taken out to complete the batching;

[0108] (2) The ingredients obtained in step (1) are pumped into a spray granulation tower for drying and granulation by a peristaltic pump. The drying and granulation temperature is 110° C. The powder after granulation is passed through a 100-mesh sieve, and the sieve residue is taken to obtain zirconium oxide antistatic composite ceramic powder.

[0109] Example 3

[0110] This embodiment provides a method for preparing a ceramic arm. Except that the ceramic powder in step (a) is replaced by high-purity alumina powder with alumina antistatic composite ceramic powder, the remaining steps and process parameters are the same as those in Example 1.

[0111] Alumina antistatic composite ceramic powder includes the following components in mass fraction:

[0112] Alumina 93%, titanium dioxide 5%, silicon dioxide 0.5%, sintering aid calcium oxide 0.5%, tin oxide 0.8% and nickel oxide 0.2%.

[0113] The batching method of alumina antistatic composite ceramic powder comprises the following steps:

[0114] (1) placing alumina antistatic composite ceramic powder into a ball mill, adding water and a dispersant, and ball milling at a speed of 260 r / min for 60 h, then adding a binder, and continuing ball milling for 5 to 15 h to obtain a slurry;

[0115] Among them, the dispersant is ammonium citrate, the mass of ammonium citrate is 0.3wt% of the total amount of all components in the alumina antistatic composite ceramic powder, the adhesive is PB-72, the mass of PB-72 is 0.5wt% of the total amount of all components in the alumina antistatic composite ceramic powder, and the volume ratio of balls, materials and water is 3:1:0.5.

[0116] (2) passing the slurry through a 160-mesh sieve and performing spray granulation, and then screening the powder obtained by the spray granulation through a double-layer sieve, and the sieve material is alumina antistatic composite ceramic powder;

[0117] Among them, the mesh number of the upper layer of the double-layer sieve is 60 mesh, and the mesh number of the lower layer sieve is 120 mesh;

[0118] The process of spray granulation is as follows: inlet temperature is 300°C, outlet temperature is 120°C, negative pressure is 60Pa, atomizer frequency is 20HZ, atomizer speed is 9000r / min, and feed pump rate is 25mL / min.

[0119] Example 4

[0120] This embodiment provides a method for preparing a ceramic arm. Except that the ceramic powder in step (a) is replaced by silicon carbide composite ceramic powder from high-purity alumina powder, the remaining steps and process parameters are the same as those in Example 1.

[0121] The silicon carbide composite ceramic powder includes the following components in mass fractions: 96% silicon carbide, 1% yttrium oxide, 0.2% calcium fluoride, 1.3% boron carbide and 1.5% aluminum oxide.

[0122] The batching method of silicon carbide composite ceramic powder comprises the following steps:

[0123] (1) drying the magnesium silicide powder in a vacuum oven at 120° C. for 12 h;

[0124] (2) Under the protection of argon atmosphere, first put 1g of magnesium silicide into the ball mill, then put the grinding balls into the ball mill and seal it, where the mass ratio of the grinding balls to the material is 30:1; after evacuation, then pass 5bar CO2 gas into the ball mill, and keep the ball mill at 300rpm for 6h at room temperature. After the reaction is completed, take out the solid product, soak it with 0.5mol / L dilute hydrochloric acid and 0.1mol / L hydrofluoric acid in turn, filter it, and wash it with deionized water until the solution is neutral, dry it at 120℃, and cool it to obtain silicon carbide powder;

[0125] (3) The prepared silicon carbide, yttrium oxide, calcium fluoride, boron carbide and aluminum oxide are weighed according to the weight ratio, ball-milled and mixed, and a dispersant polyacrylamide (the amount of which is 0.5% of the mass of the silicon carbide composite ceramic powder) is added, and spray granulation is performed to obtain silicon carbide composite ceramic powder.

[0126] Comparative Example 1

[0127] This comparative example provides a method for preparing a ceramic arm, comprising the following steps:

[0128] (1) placing commercially available high-purity alumina granulated powder of more than 99.98% into a mold and pressing it into shape to obtain a pressed plate;

[0129] (2) placing the pressed plate obtained in step (1) into a high-temperature sintering furnace for sintering, heating the plate to 1600° C. over a 0.80 h period and maintaining the temperature for 6 h to obtain a ceramic plate;

[0130] (3) The ceramic plate obtained in step (2) is first flat-ground on two surfaces, then cut into plates of the required thickness for the arm, and then CNC-processed into an airway-shaped plate A, and then flat-ground into a patch plate B with the same airway shape, to obtain arm A plate and arm B plate respectively;

[0131] (4) The processed arm A plate and arm B plate are bonded together with high temperature glue (high temperature resistance is about 600°C), dried and baked, and the obtained product is checked for air tightness. After the air tightness is qualified, an anti-static polytetrafluoroethylene coating (coating thickness is 60μm) is sprayed on to obtain a ceramic arm.

[0132] Comparative Example 2

[0133] This comparative example provides a ceramic arm, except that the antistatic polytetrafluoroethylene coating is not sprayed, and the rest of the preparation method is the same as that of comparative example 1.

[0134] In order to compare the technical effects of the above embodiments and comparative examples, the following experimental examples are specially designed.

[0135] Experimental Example 1

[0136] The air tightness, strength, maximum operating temperature and antistatic performance of the ceramic arms provided in the embodiments of the present invention and the comparative examples were tested, and the specific results are shown in Table 1.

[0137] The strength is tested according to ASTM C1161, the maximum operating temperature is measured by a thermometer, and the antistatic performance is tested according to ANSI / ESDS7.1.

[0138] The air tightness test adopts the enterprise standard, which includes the following steps:

[0139] (1) After turning on the helium detector, calibrate the equipment according to the operating requirements;

[0140] (2) Except for the airway entrance of the ceramic arm, all other airways were sealed with Teflon tape;

[0141] (3) The airway inlet is connected and sealed with the detection port of the helium detector. Press the start button and the device displays that the leakage mass is less than 6.0*10 -8 , use helium to purge the joint. When purging, the device displays less than 6.0*10 -8 , the alarm is NO, otherwise it is OK;

[0142] (4) Record the test results;

[0143] (5) Seal the pores on the ceramic arm and pump the pressure down to -100KPa. The pumping time should not exceed 1 minute. Close the valve. If the pressure does not change after 1 hour, release the seal and release the pressure to 0 within 5 seconds.

[0144] (6) Matching wafer sealing pores;

[0145] (7) Pump down to -90KPa for no more than 1 minute, let stand for 10 seconds, then observe the value of the pore pressure gauge, which is the vacuum value, standard -80 to -100KPa;

[0146] (8) The sealed pore is depressurized to -100 KPa for no more than 1 minute, the valve is closed, and if the pressure does not change after 1 hour, the seal is released and the pressure is reduced to 0 within 5 seconds;

[0147] (9) Pump down the pressure to -90KPa for no more than 1 minute, remove the seal, release the pressure for 5 seconds, and then observe the pressure gauge value, which is the airway empty pumping value, standard 0 to -6;

[0148] (10) Matching wafer sealing pores;

[0149] (11) Pump down the pressure to -90~-100KPa, stabilize the pressure for 10 seconds, close the valve, and the pumping time should not exceed 1 minute;

[0150] (12) After closing the valve, start timing and maintain pressure for 30 seconds. The pressure relief value shall not exceed -10KPa (general test);

[0151] (13) After closing the valve, start timing and maintain pressure for 30 seconds. The pressure relief value shall not exceed -6KPa (special requirement).

[0152] Table 1

[0153]

[0154] It can be seen from Table 1 that the performance of the ceramic arms provided in the embodiments of the present invention is better than that of the ceramic arms provided in the comparative examples in all aspects.

[0155] Specifically, unlike the preparation method of the ceramic arm of the embodiment of the present invention, the ceramic arms of Comparative Examples 1 and 2 are prepared by a conventional preparation method (ceramic plates are combined to form an airway, and the ceramic plates are bonded with high-temperature adhesive). It can be seen from the data in Table 1 that the one-piece ceramic arms prepared by the preparation methods of the embodiments of the present invention have a high strength, which can reach about 400MPa, good sealing, and can be used normally at high temperatures of about 1000°C, while the strength of Comparative Examples 1 and 2 is much lower than that of the embodiments of the present invention, the sealing performance is worse than that of the embodiments, and the maximum use temperature is also low.

[0156] The ceramic arms of Examples 2, 3 and 4 are respectively prepared using different types of antistatic materials as ceramic powders, while Comparative Example 1 is an antistatic coating provided on the ceramic arm. It can be seen from the data in Table 1 that the antistatic performance of Examples 2-4 is substantially equivalent to the antistatic performance of Comparative Example 1, but since the antistatic coating of Comparative Example 1 is coated on the surface of the ceramic arm, after long-term use, the antistatic coating is prone to aging and wear, resulting in a problem of decreased antistatic performance of the ceramic arm. The inventor has compared the wear resistance of Comparative Example 1 and Example 3. Under the wear test conditions of about 1,000 times, the ceramic arm with the antistatic coating of Comparative Example 1 will experience coating wear and lose its antistatic effect, while the antistatic effect of the embodiment of the present invention will not change after 1,000 uses.

[0157] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A method for preparing a ceramic arm, characterized in that: The following steps are involved: (a) providing a granulated powder formed by a ceramic powder and an additive, wherein the additive comprises a plasticizer, a flux, a lubricant and a coupling agent; The plasticizer includes at least one of polypropylene, dibutyl phthalate or polyvinyl butyral; The flux includes paraffin and / or polyethylene glycol; The lubricant includes at least one of stearic acid, octadecyl alcohol or polyethylene wax; The coupling agent includes aluminate and / or titanate; Providing a first mold and a second mold for forming a ceramic arm to be prepared, wherein one of the first mold and the second mold has the same airway structure as the ceramic arm to be prepared; (b) adding granulated powder into a first mold and a second mold respectively, and then heating and pressurizing both molds, and demolding after cooling to obtain a first green body and a second green body, wherein one of the first green body and the second green body has the air channel structure; (c) covering the first blank and the second blank, and then placing them into a mold for heating and pressurizing to bond the first blank and the second blank, thereby obtaining an arm blank with a closed airway structure; wherein the heating temperature is 120-160° C., the pressurizing pressure is 3-50 MPa, and the pressure is maintained for 3-10 minutes; (d) degreasing and sintering the arm blank to obtain a ceramic arm; The degreasing comprises firstly performing solvent degreasing and then performing powder degreasing; When the degreasing includes first performing solvent degreasing and then performing powder degreasing, the solvent used in the solvent degreasing includes at least one of deionized water, acetone, petroleum ether, kerosene or heptane; The temperature of the solvent degreasing is 40-50°C, and the time of the solvent degreasing is 6-36h; The embedding powder used in the embedding powder degreasing comprises aluminum oxide; The temperature of the buried powder degreasing is 400-600°C, and the time of the buried powder degreasing is 40-60h; The sintering temperature is 1300-1700℃, the time required to heat up to the sintering temperature is 75-85h, and the time to keep at the sintering temperature is 5-15h; The air tightness of the ceramic arm is -90~-100KPa, and the maximum operating temperature is 1000°C.

2. The method for preparing a ceramic arm according to claim 1, characterized in that: In step (a), the ceramic powder includes at least one of high-purity alumina powder, alumina antistatic composite ceramic powder, zirconium oxide antistatic composite ceramic powder or silicon carbide composite ceramic powder.

3. The method for preparing a ceramic arm according to claim 1, characterized in that: In step (a), the method for preparing the granulated powder comprises the following steps: The ceramic powder and the additive are mixed and kneaded at high temperature, the kneaded material is cooled and solidified, and then crushed to obtain granulated powder.

4. The method for preparing a ceramic arm according to claim 3, characterized in that: In step (a), the high temperature kneading temperature is 160-220° C. and the time is 2-6 hours.

5. The method for preparing a ceramic arm according to claim 1, characterized in that: In step (b), the heating temperature is 140-190°C; And / or, the pressurized pressure is 5-30 MPa, and the pressure is maintained for 5-10 minutes.

6. A ceramic arm, characterized in that: The ceramic arm is prepared by the preparation method of any one of claims 1 to 5.

7. Application of the ceramic arm described in claim 6 in the field of semiconductor chip wafer handling equipment.

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