Conductive ceramic heating base and preparation method thereof

Abstract

The invention provides a conductive ceramic heating base and a preparation method thereof.The preparation method comprises the steps that yttrium oxide powder, titanium oxide powder and a solvent are ground and mixed, then ball material separation and sieving are conducted in sequence, and mixed slurry is obtained; wherein the weight ratio of the yttrium oxide powder to the titanium oxide powder is greater than or equal to 5; drying and granulating the mixed slurry to form a granulated powder mixture; the granulation powder mixture and the heating resistance wire are put into a mold cavity of a mold, and the joint end of the heating resistance wire is located outside the mold cavity; and applying pressure to the granulated powder mixture and the heating resistance wire by adopting a hot pressing sintering process for pressing, and heating to a sintering temperature for sintering, so that the yttrium oxide and the titanium oxide are subjected to a solid-phase reaction, and the conductive ceramic heating base is obtained. The prepared conductive ceramic heating base has good conductivity, dielectric property and heat-conducting property.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing, and in particular to a conductive ceramic heating base and a preparation method thereof. Background Art

[0002] A heating base is installed inside the chamber of the semiconductor processing equipment. The heating base is used to carry the wafer to be processed, and a heater is installed inside the heating base to heat the wafer. In order to transfer as much heat generated by the heater as possible to the wafer, the material of the heating base must have high thermal conductivity and good thermal conductivity uniformity. The material of the heating base is usually made of metals such as aluminum or aluminum alloy, but metals are relatively active and easily react with the process gas in the chamber to introduce impurities.

[0003] Currently, ceramic materials such as aluminum nitride (AlN) are often used to replace metals in some examples. Aluminum nitride not only has good thermal conductivity, but also has good dielectric properties as a dielectric material to avoid heating the base to react with the plasma ionized by the process gas.

[0004] It is understandable that there are excess charged ions on the surface of the wafer during or after the process reaction. If these charged ions gather at the edge of the wafer to undergo secondary reactions, they will affect the uniformity of the film layer deposited on the wafer. Alternatively, if these charged ions gather at the edge of the heating base and accumulate to form static electricity, they will affect the transmission of the wafer. This also places high demands on the conductive properties of the heating base, so that the heating base can quickly extract the charged ions, but the heating base made of ceramic materials such as aluminum nitride cannot meet this requirement.

[0005] Therefore, how to prepare a heating base with conductive and dielectric properties becomes an urgent problem to be solved. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a conductive ceramic heating base and a preparation method thereof.

[0007] To achieve the purpose of the present invention, a method for preparing a conductive ceramic heating base is provided, comprising:

[0008] Grinding and mixing yttrium oxide powder, titanium oxide powder and solvent, and then separating and sieving the pellets to obtain a mixed slurry; wherein the weight ratio of yttrium oxide powder to titanium oxide powder is greater than or equal to 5;

[0009] Drying and granulating the mixed slurry to form a granulated powder mixture;

[0010] The granulated powder mixture and the heating resistance wire are loaded into the mold cavity of the mold, and the joint end of the heating resistance wire is located outside the mold cavity;

[0011] The granulated powder mixture and the heating resistance wire are pressed by hot pressing and sintering process, and heated to the sintering temperature for sintering, so that yttrium oxide and titanium oxide undergo solid phase reaction to obtain a conductive ceramic heating base.

[0012] In one possible embodiment, when yttrium oxide powder, titanium oxide powder and a solvent are ground and mixed, the weight percentage of the yttrium oxide powder ranges from greater than or equal to 45% to less than or equal to 49%, and the weight percentage of the titanium oxide powder ranges from greater than or equal to 1% to less than or equal to 5%.

[0013] In one possible implementation, the sum of the weights of the yttrium oxide powder and the titanium oxide powder is equal to the weight of the solvent.

[0014] In a possible implementation, a hot pressing sintering process is used to apply pressure to the granulated powder mixture and the heating resistance wire for pressing and heating to a sintering temperature for sintering, specifically including:

[0015] Applying pressure to the granulated powder mixture and the heating resistance wire and increasing the pressure to a first pressure value, while increasing the sintering temperature to a first temperature value;

[0016] increasing the pressure to a second pressure value and simultaneously increasing the sintering temperature to a second temperature value;

[0017] The first pressure value is smaller than the second pressure value, and the first temperature value is smaller than the second temperature value.

[0018] In a possible implementation, increasing the pressure to a first pressure value and increasing the sintering temperature to a first temperature value may include:

[0019] The sintering temperature is increased at a first heating rate, and the pressure is increased at a first pressure increase rate;

[0020] When the pressure increases to the target pressure value, the pressure is maintained constant;

[0021] When the sintering temperature is increased to the target temperature value, the pressure is increased at a second pressure increase rate and the sintering temperature is increased at a first temperature increase rate, so that the pressure and the sintering temperature reach the first pressure value and the first temperature value respectively after a first preset time;

[0022] The target pressure value is less than the first pressure value, the target temperature value is less than the first temperature value, and the first pressure increase rate is less than the second pressure increase rate.

[0023] In a possible implementation, increasing the pressure to a second pressure value and increasing the sintering temperature to a second temperature value specifically include:

[0024] The sintering temperature is increased at a second temperature increasing rate, and the pressure is increased at a third pressure increasing rate, so that the pressure and the sintering temperature reach a second pressure value and a second temperature value, respectively.

[0025] In a possible implementation manner, the first heating rate is greater than the second heating rate, and the second heating rate is less than the third heating rate.

[0026] In a possible implementation manner, the first pressure value is 15 MPa, the first temperature value is 900° C. to 1000° C., and the sintering time is 4 hours;

[0027] The second pressure value is 25 MPa to 30 MPa, the second temperature value is 1200° C. to 1400° C., and the sintering time is 2 hours to 4 hours.

[0028] In a possible implementation, when the yttrium oxide powder, titanium oxide powder and solvent are ground and mixed, the grinding and mixing time is 12 hours to 24 hours, and the particles are ground to a particle size of 1 um to 2 um.

[0029] In a possible implementation manner, the particle size of the granulated powder mixture is not greater than 10 um.

[0030] In a possible implementation manner, after obtaining the conductive ceramic heating base, the preparation method further comprises:

[0031] The temperature of the conductive ceramic heating base is reduced until the annealing temperature is reached and then kept warm, while the pressure is reduced to a third pressure value.

[0032] In a possible implementation, lowering the temperature of the conductive ceramic heating base until the annealing temperature is reached for heat preservation, and at the same time lowering the pressure to a third pressure value, specifically includes:

[0033] The temperature of the conductive ceramic heating base is reduced at a preset cooling rate. When the temperature of the conductive ceramic heating base reaches the target threshold, the pressure is reduced at a preset pressure reduction rate so that the pressure and the temperature of the conductive ceramic heating base reach a third pressure value and an annealing temperature respectively after a second preset time.

[0034] In a possible implementation manner, the third pressure value is 5 MPa, the annealing temperature is 800° C., and the insulation time is 30 minutes.

[0035] In a possible implementation manner, after obtaining the conductive ceramic heating base,

[0036] The preparation method also includes:

[0037] releasing the conductive ceramic heating base from the mold;

[0038] Grinding and polishing the outer surface of the conductive ceramic heating base;

[0039] Cleaning the conductive ceramic heating base;

[0040] The joint end of the heating resistance wire in the conductive ceramic heating base is electrically connected to the conductive rod.

[0041] As another technical solution, the present invention also provides a conductive ceramic heating base, which is prepared according to any one of the above-mentioned preparation methods of the conductive ceramic heating base of the present invention. The conductive ceramic heating base includes a ceramic body and a heating resistance wire arranged inside the ceramic body, and the ceramic body is made of yttrium oxide doped titanium oxide.

[0042] The present invention has the following beneficial effects:

[0043] The conductive ceramic heating base and the preparation method thereof provided by the present invention adopt yttrium oxide as the base powder for preparing the conductive ceramic heating base, and dope titanium oxide in the yttrium oxide. During the sintering preparation process, the yttrium oxide and the titanium oxide undergo a solid-phase substitutional doping reaction, so that the ceramic body of the conductive ceramic heating base obtained by sintering has conductive properties.

[0044] Furthermore, the crystal structure of yttrium oxide does not change during the sintering process. Therefore, the ceramic body of the manufactured conductive ceramic heating base can retain the thermal conductivity and dielectric properties of yttrium oxide while having conductive properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic flow chart of a method for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure;

[0046] Figure 2 A schematic cross-sectional view of a conductive ceramic heating base provided in an embodiment of the present disclosure;

[0047] Figure 3 A schematic diagram of the structure of a mold in a method for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure;

[0048] Figure 4 A schematic diagram of the process of step 3 in the method for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure;

[0049] Figure 5 A schematic flow chart of another method for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0050] Reference will now be made in detail to specific embodiments. Examples of specific embodiments are shown in the accompanying drawings. Although the present disclosure will be described in conjunction with these specific embodiments, it should be understood that this is not intended to limit the present disclosure to these specific embodiments. On the contrary, it is intended to cover alternatives, modifications and equivalents that may be included in the essence and scope defined by the appended claims. In the following description, many specific details are set forth to provide a thorough understanding of the disclosed embodiments. The present disclosure may be practiced without some or all of these specific details.

[0051] Some terms in the present disclosure are defined and explained below to facilitate understanding by those skilled in the art.

[0052] The term "substantially" as used in this document is a descriptive term indicating approximation and means "to a considerable extent" or "to a large extent but not entirely as specified", and is intended to avoid strict numerical boundaries of specified parameters.

[0053] As used herein, the terms "chip," "wafer," and "semiconductor wafer" may be used interchangeably.

[0054] As used herein, "yttrium oxide" shall be understood as yttrium oxide including Y2O3, and "titanium oxide" shall be understood as titanium oxide including TiO2.

[0055] As used herein, the term "sintered ceramic body" refers to the sintered ceramic article after a machining step that forms the ceramic into a specific shape for use as a heated susceptor in a chamber of a semiconductor processing apparatus as disclosed herein.

[0056] As used herein, the term "granulated powder mixture" means one or more granulated powders that are mixed together prior to a sintering process, whereby the powders form a sintered ceramic body after the sintering step.

[0057] As used herein, the term "solid solution" is defined as a mixture of different elements having the same lattice structure. The mixture within the lattice may be substitutional, where atoms from one starting crystal replace atoms from another starting crystal.

[0058] As used herein, the term "annealing" is understood herein to mean heat treating a sintered ceramic body in air.

[0059] As used herein, the term "dopant" is a substance added to a base powder to achieve desired properties in the sintered ceramic body.

[0060] As used herein, the term "ionic oxide" refers to an oxide composed of ions, the composition of which includes metal cations and O 2- ion.

[0061] As used herein, the term "polycrystalline" is composed of a plurality of crystal grains having different lattice arrangement orientations.

[0062] The conductive ceramic heating pedestal and its preparation method provided by the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings and specific embodiments. The conductive ceramic heating pedestal described herein is used in a chamber of a semiconductor processing device to carry a wafer.

[0063] Figure 1 A schematic diagram of a process for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure, Figure 2 This is a cross-sectional schematic diagram of a conductive ceramic heating base provided in an embodiment of the present disclosure. Figure 1 and Figure 2 The present disclosure provides a method for preparing a conductive ceramic heating base, the method comprising the following steps:

[0064] Step 1: Grind and mix yttrium oxide powder, titanium oxide powder and solvent, and then successively separate and sieve the pellets to obtain a mixed slurry; wherein the weight ratio of yttrium oxide powder to titanium oxide powder is greater than or equal to 5.

[0065] The weight ratio of yttrium oxide powder to titanium oxide powder can be selected according to specific needs. For example, the weight ratio of yttrium oxide powder to titanium oxide powder can be 8, 9, 11.5, 24, 40, 45, etc.

[0066] Step 2: drying and granulating the mixed slurry to form a granulated powder mixture.

[0067] Step 3: Load the granulated powder mixture and the heating resistance wire into the mold cavity of the mold, and the joint end of the heating resistance wire is located outside the mold cavity.

[0068] Step 4, using a hot pressing sintering process to apply pressure to the granulated powder mixture and the heating resistance wire for compression while heating to a sintering temperature for sintering, so that yttrium oxide and titanium oxide undergo a solid phase reaction to obtain a conductive ceramic heating base.

[0069] The hot pressing and sintering process can be implemented by using a hot pressing and sintering furnace. In step 4, the granulated powder mixture can be placed in the hot pressing and sintering furnace.

[0070] It can be understood that the preparation method can be regarded as using yttrium oxide as a base powder and titanium oxide as a dopant, and the yttrium oxide powder and titanium oxide powder are mixed and sintered. In this way, the ceramic body 110 of the sintered conductive ceramic heating base 100 is made of yttrium oxide doped titanium oxide, so as to achieve the required performance (i.e., conductive performance) in the conductive ceramic heating base 100.

[0071] The conductive ceramic heating base 100 prepared by the preparation method of this embodiment has the conductive property because:

[0072] According to step 4 of the method disclosed herein, during the hot pressing sintering process, the particles of the granulated powder mixture are aggregated, and the contact between the particles is bonded to form a polycrystal. Wherein, yttrium oxide and titanium oxide are both ionic oxides, and there are differences in the atomic radius and atomic valence of Ti atoms and Y atoms. Specifically, the atomic radius of Ti atoms is smaller than the atomic radius of Y atoms, and the atomic valence of Ti atoms is greater than the atomic valence of Y atoms. In this way, after titanium oxide is doped in yttrium oxide, the tetravalent Ti atoms replace the positions of the trivalent Y atoms in the yttrium oxide lattice, and yttrium oxide and titanium oxide form a solid solution, and excess negative charge is generated in the lattice. In order to maintain electrical neutrality, excess electrons will move to the vicinity of Ti atoms to be bound by Ti atoms, and electrons will form current when moving under an electric field, so that the ceramic body 110 of the sintered conductive ceramic heating base 100 has conductive properties.

[0073] It should be pointed out that in the present embodiment, yttrium oxide (Y2O3) is used as the base powder for preparing the conductive ceramic heating base 100, and titanium oxide is doped in the yttrium oxide. During the sintering preparation process, yttrium oxide and titanium oxide undergo a solid-phase substitutional doping reaction, and the crystal structure of yttrium oxide does not change. Therefore, the ceramic body 110 of the conductive ceramic heating base 100 obtained can retain the performance of yttrium oxide on the basis of having conductive properties. Among them, the relative dielectric constant of yttrium oxide is 12 to 20, and the thermal conductivity of yttrium oxide is as high as 13.6W / (m·K), that is, yttrium oxide has good dielectric properties and excellent thermal conductivity. As a result, the ceramic body 110 of the conductive ceramic heating base 100 has good thermal conductivity, dielectric properties and conductive properties.

[0074] In this way, when the conductive ceramic heating base 100 is applied to the chamber of the semiconductor processing equipment, the heating resistance wire 120 of the conductive ceramic heating base 100 is powered on and heated, and the ceramic body 110 of the conductive ceramic heating base 100 can quickly transfer the heat of the heating resistance wire 120 to the wafer. And the ceramic body 110 can maintain good plasma resistance due to its excellent dielectric properties, so as to avoid the introduction of impurities by side reactions with other gases in the chamber during the semiconductor production process. At the same time, because the ceramic body 110 has good electrical conductivity, during the process reaction or after the process reaction is completed, the ceramic body 110 can quickly conduct the excess charged ions on the surface of the wafer away from the wafer, so as to avoid these charged ions from gathering at the edge of the wafer to cause secondary reactions and affect the uniformity of the film layer on the wafer, or, to avoid these charged ions from gathering at the edge of the conductive ceramic heating base 100 to form static electricity to attract the wafer, so as to ensure that the wafer can be smoothly transmitted.

[0075] It is worth noting that in the implementation scheme of doping titanium in yttrium oxide, yttrium oxide powder is used as the base powder and titanium powder is used as the dopant. Since titanium is an active metal phase and yttrium oxide is an oxide, the crystallization temperatures of the oxide and the metal are quite different, and the reaction conditions of yttrium oxide and titanium are quite different. Therefore, the pressing and sintering in the preparation process often need to be carried out in steps. Specifically, the preparation process of the heating base in this scheme can be the following steps: a. Mixing yttrium oxide powder, titanium powder, binder, and diffusant; b. Pressing the mixed powder into a mold base; c. Heating the mold base to a high temperature for debinding treatment; d. Crushing the mold base after debinding; e. Sintering the crushed mold base at a high temperature to obtain a ceramic body doped with titanium in yttrium oxide.

[0076] Compared with the embodiment of using yttrium oxide powder as the base powder and titanium powder as the dopant to prepare the ceramic body of the heating base, the preparation method of this embodiment is doped with yttrium oxide and titanium oxide, and both yttrium oxide and titanium oxide are oxides, and no active metal phase is introduced. Therefore, there is no need to separate the pressing and sintering steps, and high pressure and high temperature can be applied to the mixture of yttrium oxide powder and titanium oxide powder at the same time. In this way, the binder and the diffusant are omitted, and the debinding process (i.e., step c) and the crushing process (i.e., step d) are also omitted, and the preparation method is simple and effective.

[0077] In step 1 of the method disclosed herein, the solvent may be an inorganic solvent or an organic solvent. Taking an inorganic solvent as an example, the solvent may be deionized water; taking an organic solvent as an example, the solvent may be anhydrous ethanol or acetone.

[0078] According to step 1 of the method disclosed herein, the weight ratio of yttrium oxide powder to titanium oxide powder is preferably in some embodiments of the present disclosure, when the yttrium oxide powder, titanium oxide powder and solvent are ground and mixed, the weight percentage of the yttrium oxide powder ranges from greater than or equal to 45% to less than or equal to 49%, and the weight percentage of the titanium oxide powder ranges from greater than or equal to 1% to less than or equal to 5%.

[0079] Furthermore, the sum of the weights of the yttrium oxide powder and the titanium oxide powder is equal to the weight of the solvent. In other words, the sum of the weights of the yttrium oxide powder and the titanium oxide powder accounts for half of the weight of the mixed slurry.

[0080] With this design, titanium oxide powder, yttrium oxide powder and solvent can be mixed in the following possible ratios. For example, 1) the weight percentages of titanium oxide powder, yttrium oxide powder and solvent are 1wt%, 49wt% and 50wt% respectively, and the weight ratio of yttrium oxide powder to titanium oxide powder is 49; 2) the weight percentages of titanium oxide powder, yttrium oxide powder and solvent are 2wt%, 48wt% and 50wt% respectively, and the weight ratio of yttrium oxide powder to titanium oxide powder is 24; 3) the weight percentages of titanium oxide powder, yttrium oxide powder and solvent are 3wt%, 47wt% and 50wt% respectively, and the weight ratio of yttrium oxide powder to titanium oxide powder is 15.67; 4) the weight percentages of titanium oxide powder, yttrium oxide powder and solvent are 4wt%, 46wt% and 50wt% respectively, and the weight ratio of yttrium oxide powder to titanium oxide powder is 11.5; 5) the weight percentages of titanium oxide powder, yttrium oxide powder and solvent are 5wt%, 45wt% and 50wt% respectively, and the weight ratio of yttrium oxide powder to titanium oxide powder is 9.

[0081] A heating base made of yttrium oxide not doped with titanium oxide was used as a comparative example. The resistivity of the conductive ceramic heating base 100 made according to the above ratio and the resistivity of the heating base in the comparative example were tested. The test results can be seen in Table 1.

[0082] Table 1

[0083]

[0084] It can be seen from Table 1 that the resistivity of the conductive ceramic heating base 100 manufactured by the preparation method of this embodiment is less than 50Ω·cm, which is much smaller than the resistivity of the heating base made of yttrium oxide ceramic. It can be seen that the conductive ceramic heating base 100 manufactured by the preparation method of this embodiment has a low resistivity and good conductive performance, thereby verifying the effectiveness of the preparation method of this embodiment.

[0085] In some embodiments, as in step 1 of the method disclosed herein, the step of grinding and mixing yttrium oxide powder, titanium oxide powder and solvent can be achieved by using powder preparation techniques such as dry ball milling, dry tumbling mixing, and jet milling.

[0086] In an alternative embodiment, wet ball milling, wet tumbling mixing and other powder preparation techniques may also be used for grinding and mixing. Taking wet ball milling as an example, yttrium oxide powder, titanium oxide powder and solvent may be put into a ball mill or a sand mill for grinding and mixing to obtain a grinding slurry. In this way, before the sintering process, a fine and uniform mixed slurry is obtained by grinding the yttrium oxide powder and titanium oxide powder, so that the solid phase substitutional doping reaction occurs fully during the hot pressing sintering process, which is beneficial to improve the uniformity of particle diffusion of the granulated powder mixture during the sintering process.

[0087] During ball milling, at least one of zirconium oxide (ZrO2), silicon carbide (SiC), etc. can be selected as the grinding ball medium. The diameter of the grinding ball medium can be 1 mm, 3 mm, and 5 mm.

[0088] The grinding time can be 12h to 24h, preferably 12h, preferably 24h. The longer the grinding time, the more fine and uniform the yttrium oxide powder and the titanium oxide powder can be. The particle size of the discharge from the grinding and mixing step can be 1um to 2um, so as to obtain a grinding slurry with a smaller particle size, which is conducive to obtaining a mixed slurry with a smaller particle size, so that the granulated powder mixture obtained after drying and granulation is a fine powder, and the surface energy of the fine powder is large, which improves the sintering driving force, is conducive to reducing the diffusion difficulty of the granulated powder mixture during sintering, and improving the uniformity of the grain structure of the sintered product (i.e., the ceramic body 110).

[0089] The grinding slurry is first subjected to ball material separation, and then sieved to separate the grinding ball media and the mixed powder, and filtered to obtain a mixed slurry. The grinding slurry can be optionally sieved using a sieve with a mesh size of 100 to 150 mesh, preferably a mesh size of 120 mesh, so that the size of the mixed slurry obtained after sieving is uniform.

[0090] In step 2 of the method disclosed herein, the mixed slurry can be spray dried and granulated using a spray granulator to form a spherical powder-shaped granulated powder mixture. In other embodiments, the mixed slurry can also be dried and granulated using a rotary evaporation method, a fluidized bed drying technique, or other drying techniques known to those skilled in the art.

[0091] It should be noted that after the yttrium oxide powder and the titanium oxide powder are ground and mixed to form a mixed slurry, the mixed slurry is usually dried to obtain a fine, irregularly shaped powder mixture. The powder mixture has a small particle size and a large specific surface area, and the fluidity of the powder mixture is poor. In this embodiment, the granulated powder mixture obtained by drying and granulating the mixed slurry is a powder that is approximately spherical, and the fluidity of the granulated powder mixture is improved to a certain extent, which is conducive to promoting the agglomeration of the particles of the granulated powder mixture during the sintering process, thereby facilitating the increase in the density of the sintered product (i.e., the ceramic body 110).

[0092] Moreover, compared with the powdered mixture, the spherical powder-like granulated powder mixture obtained after granulation is not too fine and has a uniform particle size, which helps to reduce the stratification phenomenon during sintering caused by the granulated powder mixture being too fine or having an uneven particle size.

[0093] The powder particle size of the granulated powder mixture may be no greater than 10 μm, preferably 10 μm. In this way, while preventing the granulated powder mixture from being too fine, it is also beneficial to avoid the granulated powder mixture from being too coarse (i.e., the powder particle size is too large) which increases the difficulty of sintering.

[0094] In addition, since the granulated powder mixture after drying is a fine powder, the crystal lattice of the fine powder is smaller, so the grain boundary diffusion is easy during the sintering process, and the required sintering temperature and sintering time can be reduced accordingly.

[0095] Figure 3 This is a schematic diagram of the structure of the mold in the method for preparing the conductive ceramic heating base provided in the embodiment of the present disclosure. Please refer to Figure 3 The mold 200 specifically includes a mold sleeve 210, an upper pressing block 230 and a lower pressing block 220. The mold sleeve 210 is cylindrical. The upper pressing block 230 and the lower pressing block 220 are sequentially nested in the mold sleeve 210 along the height direction of the mold sleeve 210. The shapes of the upper pressing block 230 and the lower pressing block 220 match the shape of the mold sleeve 210. The outer side surface of the upper pressing block 230 and the outer side surface of the lower pressing block 220 are both in close contact with the inner surface of the mold sleeve 210. The top surface of the lower pressing block 220, the inner surface of the mold sleeve 210 and the bottom surface of the upper pressing block 230 together form a mold cavity 240. In addition, the lower pressing block 220 is an internal hollow structure. Two openings are provided on the top surface of the lower pressing block 220, and the two openings are connected to the internal hollow space of the lower pressing block 220.

[0096] Figure 4 This is a schematic diagram of the process of step 3 in the method for preparing a conductive ceramic heating base provided in an embodiment of the present disclosure. Please refer to Figure 4 , as disclosed herein, step 3 includes: i) inserting the two joint ends 121 of the heating resistance wire 120 into the inner hollow space of the lower pressing block 220 through the two openings respectively, and pulling up the remaining part of the heating resistance wire 120 to be away from the top surface of the lower pressing block 220; ii) filling a part of the granulated powder mixture 300 into the cavity surrounded by the mold sleeve 210 and the lower pressing block 220, and spreading the granulated powder mixture 300 on the top surface of the lower pressing block 220; iii) The heating resistance wire 120 is bent according to a preset pattern; iv) the heating resistance wire 120 in the preset pattern is arranged on the surface of the granulated powder mixture 300 filled in the cavity facing the back of the lower pressing block 220; v) a part of the granulated powder mixture 300 is filled into the cavity and spread flat on the top of the heating resistance wire 120; vi) the upper pressing block 230 is embedded in the mold sleeve 210, and the upper pressing block 230 is fit with the surface of the granulated powder mixture 300 facing the back of the lower pressing block 220.

[0097] It should be understood that the size of the opening is adapted to the joint end 121 of the heating resistance wire 120, the joint end 121 will not escape from the internal hollow space of the lower pressing block 220 through the opening, and the granulated powder mixture 300 filled in the cavity will not enter the internal hollow space through the opening.

[0098] The amount of the granulated powder mixture 300 loaded into the cavity in step ii) and step v) of the method disclosed herein depends on the distance between the heating resistance wire 120 inside the conductive ceramic heating base 100 and the top and bottom surfaces of the conductive ceramic heating base 100. For example, along the thickness direction of the conductive ceramic heating base 100, if the distance between the heating resistance wire 120 and the top and bottom surfaces of the conductive ceramic heating base 100 is equal, that is, the heating resistance wire 120 is located in the middle, then the amount of the granulated powder mixture 300 in step ii) and step v) should be such that it can occupy 1 / 2 of the volume of the mold cavity 240 after being spread flat in the cavity.

[0099] The material of the heating resistance wire 120 can be molybdenum or tungsten carbide.

[0100] In some embodiments, step 4 of the methods disclosed herein comprises:

[0101] Step 41, applying pressure to the granulated powder mixture and the heating resistance wire and increasing the pressure to a first pressure value, and increasing the sintering temperature to a first temperature value;

[0102] Step 42, increasing the pressure to a second pressure value, and increasing the sintering temperature to a second temperature value; wherein the first pressure value is less than the second pressure value, and the first temperature value is less than the second temperature value.

[0103] In this embodiment, the hot pressing and sintering process is carried out in stages, firstly using low temperature and low pressure for hot pressing and sintering treatment, and then using high temperature and high pressure for hot pressing and sintering treatment.

[0104] Thus, during the low-temperature and low-pressure hot-pressing sintering stage, by simultaneously applying pressure and increasing temperature, the contact, heat conduction and diffusion between the particles of the granulated powder mixture are facilitated, and the solid-phase substitutional doping reaction is promoted, so that the yttrium oxide and titanium oxide basically complete the solid-phase substitutional doping reaction at this stage. Moreover, the lower sintering temperature helps to suppress the crystal growth rate, and the lower pressure helps to suppress the grain boundary migration, thereby suppressing the excessive growth of the grains, so that the sintered product (i.e., the ceramic body 110) has finer grains and higher mechanical strength, which is conducive to the formation of a dense structure.

[0105] The following formula 1 is Murray's hot pressing densification equation, where ρ E is the limiting density, γ is the surface tension of the material, n is the number of pores per unit volume of the corresponding dense material, τ C is the yield strength of the material and P is the applied pressure.

[0106]

[0107] According to Murray's hot pressing densification equation, it can be seen that when the sintering temperature remains unchanged, increasing the pressure P can increase the ultimate density of the sintered ceramic body. When the pressure P remains unchanged, increasing the sintering temperature, the yield strength τ of the material C Based on this, after the low-temperature and low-pressure hot-pressing sintering stage, the solid-phase reaction of yttrium oxide and titanium oxide is basically completed, and then the hot-pressing sintering process is converted to the high-temperature and high-pressure hot-pressing sintering stage by increasing the pressure and the sintering temperature. At this time, the higher sintering temperature helps to increase the sintering driving force, so as to promote the growth of the sintering neck and the closure of the pores, thereby helping to improve the density of the ceramic body 110.

[0108] The first pressure value can be 2.5 MPa to 15 MPa, preferably 2.5 MPa to 10 MPa, preferably 2.5 MPa to 10 MPa, preferably 2.5 MPa, preferably 10 MPa, preferably 15 MPa. Too high pressure will inhibit ion diffusion and atomic migration on titanium oxide and yttrium oxide. Therefore, during the low temperature and low pressure hot pressing sintering stage, the pressure is controlled at 2.5 MPa to 15 MPa to avoid the solid phase substitutional doping reaction being inhibited.

[0109] The first temperature value is 900° C. to 1000° C., preferably 900° C., preferably 1000° C. The duration of the low-temperature and low-pressure hot-pressing sintering process may be 4 hours. In other words, the sintering duration of step 41 may be 4 hours.

[0110] The second pressure value may be 25 MPa to 30 MPa, preferably 25 MPa, preferably 30 MPa. The second temperature value may be 1200° C. to 1400° C., preferably 1200° C. to 1300° C., preferably 1300° C. to 1400° C., preferably 1200° C., preferably 1400° C. The duration of the high temperature and high pressure hot pressing sintering process may be 2 hours to 4 hours, in other words, the sintering duration of step 42 may be 2 hours to 4 hours, preferably 2 hours, preferably 4 hours.

[0111] In some embodiments of the present disclosure, the above step 41 can be implemented by the following steps.

[0112] Step 411, increasing the sintering temperature at a first heating rate, and increasing the pressure at a first pressure increase rate.

[0113] Step 412, when the pressure increases to the target pressure value, the pressure is maintained constant.

[0114] Step 413, when the sintering temperature increases to the target temperature value, the pressure is increased at a second pressure increase rate and the sintering temperature is increased at a first temperature increase rate, so that the pressure and the sintering temperature reach the first pressure value and the first temperature value respectively after a first preset time.

[0115] Furthermore, the target pressure value is lower than the first pressure value, the target temperature value is lower than the first temperature value, and the first pressure increase rate is lower than the second pressure increase rate.

[0116] Based on the embodiment in which the first pressure value is 2.5 MPa to 15 MPa, the target pressure value may be 2.5 MPa to 5 MPa, preferably 2.5 MPa, preferably 5 MPa. Based on the embodiment in which the first temperature value is 900° C. to 1000° C., the target temperature value may be 800° C. to 900° C., preferably 800° C., preferably 850° C., preferably 900° C.

[0117] By applying pressure to the granulated powder mixture, the granulated powder mixture can be compacted on the one hand, and on the other hand, the grain boundary migration during the sintering process can be inhibited, thereby inhibiting excessive grain growth. In addition, according to the content described above, it can be seen that too high pressure will inhibit the ion diffusion and atomic migration on titanium oxide and yttrium oxide. In this embodiment, by designing the pressure to be maintained at a lower target pressure value during the process of increasing the sintering temperature to the target pressure value, the pressure is at a lower pressure value for a longer time during the low-temperature and low-pressure hot pressing sintering stage, which is conducive to promoting the full occurrence of the solid-phase substitutional doping reaction as much as possible.

[0118] In some embodiments, the specific implementation process of the above step 42 may be: increasing the sintering temperature at a second heating rate, and increasing the pressure at a third pressure increase rate, so that the pressure and the sintering temperature reach the second pressure value and the second temperature value respectively.

[0119] As a further optional embodiment, the first heating rate is greater than the second heating rate, and the second pressure increasing rate is less than the third pressure increasing rate. In combination with the above content, it can be seen that the first pressure increasing rate < the second pressure increasing rate < the third pressure increasing rate.

[0120] With this design, a relatively high heating rate and a relatively low pressure increase rate are used in the low temperature and low pressure hot pressing sintering stage. On the one hand, it is beneficial to quickly increase the sintering temperature in this stage to the first temperature value, so as to reduce the grain growth rate; on the other hand, by designing a relatively low pressure increase rate, the time for the pressure to reach the first pressure value is prolonged as much as possible, so as to suppress excessive grain growth and promote the solid phase substitutional doping reaction to be basically completed in this stage.

[0121] In addition, a lower heating rate and a higher pressure increase rate are used in the high temperature and high pressure hot pressing sintering stage. First, the sintering temperature in this stage increases slowly, which is conducive to improving the uniformity of heating; second, the relatively low temperature in this stage helps the growth of the sintering neck. Therefore, by designing a lower heating rate, the time when the sintering temperature is at a higher temperature is shortened as much as possible, reducing the effect of high temperature on the growth of the sintering neck; third, by rapidly increasing the pressure, it helps to more effectively inhibit the growth of grains.

[0122] For example, the first temperature increase rate may be 10° C. / min, and the second temperature increase rate may be 5° C. / min. The first pressure increase rate may be 1.2 MPa / min, the second pressure increase rate may be 1.25 MPa / min, and the third pressure increase rate may be 1.5 MPa / min.

[0123] In a specific example, the target pressure value is set to 2.5 MPa, the target temperature value is set to 900° C., the first temperature value is set to 1000° C., the first pressure value is set to 15 MPa, the second temperature value is set to 1400° C., and the second pressure value is set to 30 MPa. The exemplary process of step 4 of the method disclosed herein is:

[0124] Low temperature and low pressure hot pressing sintering stage. The sintering temperature is increased from room temperature at a heating rate of 10℃ / min, and the pressure is increased from atmospheric pressure at a pressure increase rate of 1.2MPa / min, so that the pressure rises to 2.5MPa in 2min, and then the pressure is maintained to maintain the pressure at 2.5MPa; until the sintering temperature rises to 900℃, the sintering temperature is continued to be increased at a heating rate of 10℃ / min, and the pressure is increased at a pressure increase rate of 1.25MPa / min. When the first preset time reaches 10min, the pressure is increased from 2.5MPa to 15MPa, and the sintering temperature is increased from 900℃ to 1000℃, and sintered for 4h under this process environment. Among them, the atmospheric pressure is 0.1MPa.

[0125] High temperature and high pressure hot pressing sintering stage. The sintering temperature is increased from 1000℃ at a heating rate of 5℃ / min, and the pressure is increased from 15MPa at a pressure increase rate of 1.5MPa / min. When the time reaches 10min, the pressure is increased to 30MPa accordingly; then the sintering temperature is continued to be increased at a heating rate of 5℃ / min until the sintering temperature reaches 1400℃, and sintering is carried out for 4h under this process environment.

[0126] Figure 5 A schematic diagram of a process for preparing another conductive ceramic heating base provided in an embodiment of the present disclosure. In some embodiments of the present disclosure, such as Figure 5 As shown, after step 4, the preparation method may further include step 5.

[0127] Step 5, lowering the temperature of the conductive ceramic heating base until it reaches the annealing temperature for heat preservation, and at the same time lowering the pressure to a third pressure value.

[0128] According to process step 5 of the method disclosed herein, the conductive ceramic heated susceptor 100 may be passively cooled by removing the heat source, using natural or forced convection, until the annealing temperature is reached.

[0129] After the hot pressing sintering process, the conductive ceramic heating base 100 is annealed and kept warm to allow atoms to flow and rearrange, impurities on the ceramic body 110 of the conductive ceramic heating base 100 migrate to the surface, and the ceramic body 110 shrinks and refines, thereby improving the mechanical strength of the ceramic body 110.

[0130] The annealing temperature may be 800° C. The third pressure value is less than the second pressure value, and the third pressure value may be 5 MPa. The holding time of process step 5 according to the method disclosed herein may be 30 minutes.

[0131] In some embodiments, the specific implementation process of the above step 5 may be: lowering the temperature of the conductive ceramic heating base 100 at a preset cooling rate, and when the temperature of the conductive ceramic heating base 100 reaches the target threshold, reducing the pressure at a preset pressure reduction rate, so that the pressure and the temperature of the conductive ceramic heating base reach a third pressure value and annealing temperature respectively after a second preset time.

[0132] It can be understood that the target threshold is greater than the annealing temperature and less than the second temperature value. Based on the embodiment in which the annealing temperature is 800°C, the target threshold may be 900°C, for example.

[0133] With this design, the temperature of the conductive ceramic heating base 100 is first reduced, and the pressure is unloaded when the temperature of the conductive ceramic heating base 100 reaches the target threshold. Furthermore, after the pressure reaches the third pressure value and the temperature of the conductive ceramic heating base reaches the annealing temperature, the conductive ceramic heating base 100 is kept warm in a low temperature and low pressure environment to facilitate atomic flow and rearrangement.

[0134] The preset temperature drop rate may be set to be less than the first temperature increase rate, for example, the preset temperature drop rate may be 5°C / min. The preset pressure drop rate may be set to be less than the third pressure increase rate, for example, the preset pressure drop rate may be 1.25 MPa / min.

[0135] In a specific example, the preset cooling rate is set to 35°C / min, the target threshold is set to 900°C, and the preset pressure reduction rate is set to 1.25MPa / min. Step 5 of the method disclosed in this article can be implemented according to the following steps: Ⅰ) reducing the temperature of the conductive ceramic heating base at a cooling rate of 5°C / min; Ⅱ) until the temperature drops to 900°C, continue to reduce the temperature of the conductive ceramic heating base at a cooling rate of 5°C / min, and at the same time reduce the pressure at a pressure reduction rate of 1.25MPa / min, then when the second preset time reaches 20min, the pressure is correspondingly reduced to 5Mpa, and the temperature of the conductive ceramic heating base is correspondingly reduced to 800°C; Ⅲ) keep warm at 800°C for 30 minutes; Ⅳ) naturally cool to room temperature.

[0136] According to step 4 of the method disclosed herein, the hot pressing sintering process can be performed in a nitrogen environment, and the nitrogen plays a protective role. In other embodiments of the present disclosure, the nitrogen can also be replaced by other inert gases. The vacuum degree of the nitrogen environment can optionally be 5Pa to 10Pa, preferably 10Pa.

[0137] In some embodiments of the present disclosure, after step 4, as Figure 5 As shown, the preparation method may also include: step 6, removing the conductive ceramic heating base from the mold; step 7, grinding and polishing the outer surface of the conductive ceramic heating base; step 8, cleaning the conductive ceramic heating base; step 9, electrically connecting the connector end of the heating resistance wire in the conductive ceramic heating base to the conductive rod.

[0138] In this embodiment, impurities on the outer surface of the conductive ceramic heating base 100 can be removed by grinding and polishing the outer surface of the conductive ceramic heating base 100. By connecting the joint end 121 of the heating resistance wire 120 to the conductive rod, when the conductive ceramic heating base 100 is applied to the chamber, the joint end 121 of the heating resistance wire 120 can be conveniently connected to a power source through the conductive rod to conduct current.

[0139] It should be understood that in the embodiment where the preparation method includes step 5, step 6 can be performed after step 5. Therefore, by annealing the conductive ceramic heating base 100, it is helpful to remove the excess stress of the ceramic body 110 of the conductive ceramic heating base 100, thereby helping to avoid cracking of the ceramic body 110 due to grinding when performing step 7.

[0140] When executing process step 7 of the method disclosed herein, the joint end 121 of the heating resistance wire 120 exposed outside the ceramic body 110 needs to be avoided to avoid damaging the joint end 121 of the heating resistance wire 120 .

[0141] Step 7 of the method disclosed herein may include: step 71, rough grinding and polishing the outer surface of the conductive ceramic heating base; step 72, fine grinding the area on the outer surface of the conductive ceramic heating base for supporting the wafer.

[0142] The conductive ceramic heating base 100 can be placed on a surface grinder for rough grinding and polishing, and the conductive ceramic heating base 100 can be placed on a precision machine tool for fine grinding. Of course, other rough grinding equipment known to those skilled in the art can also be used to rough grind the conductive ceramic heating base 100.

[0143] According to this embodiment, the outer surface of the conductive ceramic heating base 100 is firstly rough ground, and then the area for carrying the wafer is formed by fine grinding. In this way, while ensuring that the area for carrying the wafer on the outer surface of the conductive ceramic heating base 100 has a high precision, the processing technology is simplified and the preparation efficiency is improved.

[0144] It should be understood that process step 8 of the method disclosed above is optional. After grinding and polishing the outer surface of the conductive ceramic heating base 100, the conductive ceramic heating base 100 is cleaned so that the outer surface of the conductive ceramic heating base 100 has a high degree of cleanliness to prevent the conductive ceramic heating base 100 from contaminating the chamber. The step of cleaning the conductive ceramic heating base 100 can be achieved by ultrasonic cleaning, laser cleaning, ultraviolet cleaning, plasma cleaning, dry ice cleaning, wet cleaning and other technologies.

[0145] The manufacturing process of the conductive rod used as an embodiment of the present disclosure may specifically include welding the joint end 121 of the heating resistance wire 120 to the kovar alloy; welding the kovar alloy to the nickel rod. In this way, the kovar alloy and the nickel rod together constitute the conductive rod, and the conductive rod containing the kovar alloy and the nickel material has good high temperature resistance. Among them, the welding connection method is not limited to welding methods such as fusion welding, resistance welding, and brazing.

[0146] As another technical solution, the embodiment of the present disclosure also provides a conductive ceramic heating base 100, which is prepared according to any one of the preparation methods disclosed herein. Figure 2 As shown, the conductive ceramic heating base 100 includes a ceramic body 110 and a heating resistance wire 120 arranged inside the ceramic body 110, and the composition of the ceramic body 110 is yttrium oxide doped titanium oxide.

[0147] In combination with the foregoing, it can be known that by using yttrium oxide (Y2O3) as the base powder for preparing the conductive ceramic heating base 100, and doping titanium oxide in the yttrium oxide, the ceramic body 110 of the conductive ceramic heating base 100 obtained has good thermal conductivity and dielectric properties on the basis of having conductive properties. In this way, when the conductive ceramic heating base 100 of this embodiment is used in the chamber of a semiconductor processing device, the ceramic body 110 can quickly conduct the excess charged ions on the surface of the wafer away from the wafer, so as to prevent these charged ions from gathering at the edge of the wafer to cause secondary reactions and affect the uniformity of the film layer on the wafer, or to prevent these charged ions from gathering at the edge of the conductive ceramic heating base 100 to form electrostatic attraction to the wafer, so as to ensure that the wafer can be smoothly transmitted.

[0148] In some embodiments, in the embodiment where the mixing ratio of yttrium oxide powder, titanium oxide powder and solvent is such that the sum of the weight of yttrium oxide powder and titanium oxide powder accounts for one-half of the total weight, and the weight percentage of yttrium oxide powder is in the range of greater than or equal to 45wt% and less than or equal to 49wt%, and the weight percentage of titanium oxide powder is in the range of greater than or equal to 1wt% and less than or equal to 5wt%, the resistivity of the prepared conductive ceramic heating base 100 is less than 50Ω·cm, which is much smaller than the resistivity of the heating base made of yttrium oxide ceramic, and the conductive ceramic heating base 100 has good conductivity.

[0149] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for preparing a conductive ceramic heating base, characterized in that: include: Grinding and mixing yttrium oxide powder, titanium oxide powder and solvent, and then separating and sieving the pellets to obtain a mixed slurry; wherein the weight ratio of the yttrium oxide powder to the titanium oxide powder is greater than or equal to 5; Drying and granulating the mixed slurry to form a granulated powder mixture; The granulated powder mixture and the heating resistance wire are loaded into a mold cavity of a mold, and the joint end of the heating resistance wire is located outside the mold cavity; A hot pressing sintering process is used to apply pressure to the granulated powder mixture and the heating resistance wire for compression while heating to a sintering temperature for sintering, so that yttrium oxide and titanium oxide undergo a solid phase reaction to obtain a conductive ceramic heating base.

2. The preparation method according to claim 1, characterized in that: When yttrium oxide powder, titanium oxide powder and solvent are ground and mixed, the weight percentage of the yttrium oxide powder is greater than or equal to 45% and less than or equal to 49%, and the weight percentage of the titanium oxide powder is greater than or equal to 1% and less than or equal to 5%.

3. The preparation method according to claim 2, characterized in that: The sum of the weights of the yttrium oxide powder and the titanium oxide powder is equal to the weight of the solvent.

4. The preparation method according to claim 1, characterized in that: The hot pressing sintering process is used to apply pressure to the granulated powder mixture and the heating resistance wire for pressing and heating to a sintering temperature for sintering, specifically comprising: Applying pressure to the granulated powder mixture and the heating resistance wire and increasing the pressure to a first pressure value, while increasing the sintering temperature to a first temperature value; increasing the pressure to a second pressure value and increasing the sintering temperature to a second temperature value; The first pressure value is smaller than the second pressure value, and the first temperature value is smaller than the second temperature value.

5. The preparation method according to claim 4, characterized in that: Increasing the pressure to a first pressure value and simultaneously increasing the sintering temperature to a first temperature value specifically includes: The sintering temperature is increased at a first temperature increase rate, and the pressure is increased at a first pressure increase rate; When the pressure increases to a target pressure value, maintaining the pressure unchanged; When the sintering temperature increases to a target temperature value, the pressure is increased at a second pressure increase rate and the sintering temperature is increased at a first temperature increase rate, so that the pressure and the sintering temperature reach the first pressure value and the first temperature value respectively after a first preset time; The target pressure value is smaller than the first pressure value, the target temperature value is smaller than the first temperature value, and the first pressure increasing rate is smaller than the second pressure increasing rate.

6. The preparation method according to claim 5, characterized in that: Increasing the pressure to a second pressure value and simultaneously increasing the sintering temperature to a second temperature value specifically comprises: The sintering temperature is increased at a second temperature increase rate, and the pressure is increased at a third pressure increase rate, so that the pressure and the sintering temperature reach the second pressure value and the second temperature value, respectively.

7. The preparation method according to claim 6, characterized in that: The first temperature increasing rate is greater than the second temperature increasing rate, and the second temperature increasing rate is less than the third temperature increasing rate.

8. The preparation method according to claim 4, characterized in that: The first pressure value is 15 MPa, the first temperature value is 900° C. to 1000° C., and the sintering time is 4 hours; The second pressure value is 25 MPa to 30 MPa, the second temperature value is 1200° C. to 1400° C., and the sintering time is 2 hours to 4 hours.

9. The preparation method according to claim 1, characterized in that: When the yttrium oxide powder, titanium oxide powder and solvent are ground and mixed, the grinding and mixing time is 12 hours to 24 hours, and the particles are ground to a size of 1 um to 2 um.

10. The preparation method according to claim 1, characterized in that: The powder particle size of the granulated powder mixture is not greater than 10 um.

11. The preparation method according to any one of claims 1 to 10, characterized in that: After obtaining the conductive ceramic heating base, the preparation method further comprises: The temperature of the conductive ceramic heating base is lowered until the annealing temperature is reached and then kept warm, and at the same time, the pressure is lowered to a third pressure value.

12. The preparation method according to claim 11, characterized in that: The temperature of the conductive ceramic heating base is lowered until it reaches the annealing temperature for heat preservation, and the pressure is lowered to a third pressure value, specifically including: The temperature of the conductive ceramic heating base is reduced at a preset cooling rate. When the temperature of the conductive ceramic heating base reaches a target threshold, the pressure is reduced at a preset pressure reduction rate so that the pressure and the temperature of the conductive ceramic heating base reach the third pressure value and the annealing temperature respectively after a second preset time.

13. The preparation method according to claim 11, characterized in that: The third pressure value is 5 MPa, the annealing temperature is 800° C., and the insulation time is 30 minutes.

14. The preparation method according to any one of claims 1 to 10, characterized in that: After obtaining the conductive ceramic heating base, the preparation method further comprises: removing the conductive ceramic heating base from the mold; Grinding and polishing the outer surface of the conductive ceramic heating base; Cleaning the conductive ceramic heating base; The joint end of the heating resistance wire in the conductive ceramic heating base is electrically connected to the conductive rod.

15. A conductive ceramic heating base, characterized in that: The conductive ceramic heating base is made by the preparation method according to any one of claims 1 to 14; The conductive ceramic heating base comprises a ceramic body and a heating resistance wire arranged inside the ceramic body, and the ceramic body is made of yttrium oxide doped titanium oxide.

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