Multilayer wiring chuck hole filling slurry and its preparation method and application

Abstract

The present invention provides a multi-layer wiring electrostatic chuck hole-filling slurry, its preparation method, and application. By using a tungsten / molybdenum powder-graded particle mixture as a conductive phase to form an efficient conductive network in the slurry, and by pre-treating the inorganic glass powder to achieve higher dispersibility, the type and proportion of each component are adjusted to prepare a hole-filling slurry suitable for multi-layer wiring chucks with high aperture ratios. This invention overcomes the shortcomings of traditional high-temperature co-fired hole-filling slurries, such as front-side depression and easy loss of back-side edges when filling high-aspect-ratio holes in chucks. The slurry also exhibits excellent electrical conductivity and sintering properties, providing a hole-filling slurry with high adaptability, high stability, and high electrical conductivity for chucks that achieve high-aspect-depth hole filling, multi-layer wiring, and high-temperature co-firing.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature co-fired ceramic slurries, and in particular to a slurry for filling holes with a high aspect ratio and a multi-layer wiring chuck, as well as a preparation method and application thereof. Background Art

[0002] In the semiconductor field, ceramics are often used in various electronic devices such as chips, heaters, chucks, etc. Ceramic substrates are mostly modularly formed in a stacked manner, and are connected by filling slurry through holes that run through the top and bottom to achieve internal wiring and external connections. For example, in the packaging of high-frequency, high-voltage electronic components such as power amplifiers and radio frequency modules, the use of hole-filling slurry to fill the vias of the ceramic package substrate can improve the electrical and mechanical properties of the package and ensure the stable operation of the components in harsh environments. A ceramic electrostatic chuck for semiconductors is a device used to fix and support silicon wafers or other semiconductor material substrates during the semiconductor manufacturing process. It firmly adsorbs substrates such as wafers on its surface through electrostatic attraction, ensuring that the substrate can remain stable and motionless during high-precision processes such as thin film deposition, etching, and photolithography.

[0003] To achieve electrostatic adsorption, ceramic electrostatic chucks require alternating layers of ceramic greenware and metal wiring slurry to form adsorption layers and electrode heating layers. The adsorption and electrode heating layers of the ceramic chuck are then filled with slurry through the interlayer vias. This slurry is then sintered at high temperature to achieve metal wiring and connections between the layers. In recent years, with the rapid development of the semiconductor industry, ceramic electrostatic chucks have become more widely used. Currently, the hole-filling process used in electrostatic chucks primarily relies on high-temperature co-firing. The hole-filling process in electrostatic chucks has its own unique characteristics: the holes are larger both horizontally and through the thickness, requiring more slurry. Traditional hole-filling slurries are prone to front-side hole depression and back-side hole loss when filling high-aspect-ratio vias. This leads to broken wires and insufficient conductivity between sintered layers after filling. For electrostatic chucks with high-aspect-ratio multi-layer wiring, how to address these issues of broken wires and insufficient conductivity after sintering under high temperature and high pressure, while also maintaining excellent conductive properties, remains a pressing technical challenge. Summary of the Invention

[0004] In response to the above-mentioned problems that traditional hole-filling slurries have many shortcomings when filling holes with high depth and wide aperture, the present invention provides a multi-layer wiring chuck hole-filling slurry and a preparation method thereof, which can solve the problems of traditional hole-filling slurries in multi-layer wiring electrostatic chucks with high diameter-to-depth ratio holes, incomplete hole filling, great processing difficulty, and poor conductivity caused by mismatch with green porcelain shrinkage. At the same time, it also has good stability and reliability under harsh conditions such as high temperature and high pressure. More importantly, it significantly improves the electrical conductivity of the hole-filling slurry, greatly improving the performance of multi-layer wiring electrostatic chucks with high diameter-to-depth ratio holes.

[0005] The first aspect of the present invention provides a hole-filling slurry, which comprises a conductive phase powder, an inorganic glass powder, an organic carrier, and an additive;

[0006] The conductive phase powder is composed of tungsten powder and molybdenum powder, and the particle size of the conductive phase powder is selected from 0.3-2 μm; the tungsten powder is composed of a first tungsten powder and a second tungsten powder, and the particle size of the second tungsten powder is selected from 1.0-2.0 μm, and the particle sizes of the first tungsten powder and the second tungsten powder differ by at least 0.5 μm;

[0007] Furthermore, in the conductive phase powder, the mass ratio of tungsten powder to molybdenum powder is 7-8:3-2; and the mass ratio of the first tungsten powder to the second tungsten powder is 2-4:6-8.

[0008] Furthermore, the pore filling slurry is composed of the following components in percentage by mass:

[0009] Conductive phase powder 80-88%;

[0010] Inorganic glass powder 3% to 10%;

[0011] Organic carrier 3% to 10%;

[0012] Additives 0.5%~2.5%.

[0013] Furthermore, the particle size of the first tungsten powder is selected from 0.3-1.0 μm;

[0014] Furthermore, the inorganic glass powder is selected from the Al2O3-MgO-SiO2 system.

[0015] Preferably, the inorganic glass powder is obtained by pretreatment, wherein the pretreatment includes wet ball milling, and the ball milling medium is high-purity acetone and zirconia balls with a diameter of 2 mm;

[0016] Furthermore, the organic carrier includes a resin and an organic solvent, and the resin is selected from at least one of ethyl cellulose, acrylic resin, and polyvinyl butyral resin; preferably at least one of ethyl cellulose and acrylic resin;

[0017] The organic solvent is selected from at least one of terpineol and diethylene glycol butyl ether acetate;

[0018] The organic carrier may further include a defoamer and a dispersant; the defoamer is selected from at least one of polyethylene glycol, polyoxypropylene glycol ether, and glycerol fatty acid ester, and the dispersant is selected from at least one of lecithin, tributyl citrate, and ethylene glycol diacetate.

[0019] Furthermore, the auxiliary agent is selected from at least one of a dispersant, a defoaming agent, a solvent, and a thixotropic agent; the dispersant is selected from at least one of lecithin, tributyl citrate, and ethylene glycol diacetate; the thixotropic agent is selected from at least one of hydrogenated castor oil and polyamide wax; the defoaming agent is selected from at least one of polyethylene glycol, polyoxypropylene glycol ether, and glycerol fatty acid ester; and the solvent is selected from at least one of dibutyl phthalate, terpineol, and diethylene glycol butyl ether acetate.

[0020] The second aspect of the present invention provides a method for preparing the above-mentioned pore-filling slurry, comprising a batching and mixing step and a roll-rolling and dispersing step;

[0021] Furthermore, the ingredient mixing step is: the prepared conductive phase tungsten / molybdenum graded particle mixed powder, pretreated inorganic glass powder, organic carrier and additives are added to the mixing equipment in sequence according to the set mass percentage, and preliminary mixing is performed.

[0022] The roller dispersion step comprises: finely mixing the preliminarily mixed materials, using a three-roll mill, and performing multiple grinding and dispersion to ensure that the components are fully contacted and mixed.

[0023] Furthermore, the preparation process of the conductive phase tungsten / molybdenum powder-graded particle mixed powder is as follows:

[0024] (1) Add tungsten powder and molybdenum powder into the mixing equipment and mix them thoroughly to make the two powders evenly distributed;

[0025] (2) Dry ball milling is performed, and the powder after ball milling is sieved to obtain a conductive phase tungsten / molybdenum powder-graded particle mixed powder.

[0026] The ball mill adopts a horizontal ball mill; the ball milling medium is high-purity zirconia balls; the ball milling frequency is 12.5-17.5 Hz, the ball milling time is 12 hours; the material-ball ratio is controlled at 2-2.5; the mesh size of the sieve is 150 mesh;

[0027] Furthermore, the inorganic glass powder pretreatment includes wet ball milling, vacuum drying, mechanical crushing, and screening steps; the ball milling medium is high-purity acetone and zirconia balls with a diameter of 2 mm;

[0028] Specifically, the inorganic glass powder pretreatment includes: (1) wet ball milling: using inorganic glass powder of the Al2O3-MgO-SiO2 system, high-purity acetone as the ball milling medium, adding the inorganic glass powder and the ball milling medium in a certain ratio into a ball mill, adding 2mm diameter zirconia balls for wet ball milling, and controlling the material-to-ball ratio at 1.2-1.5. Ball milling refines the glass powder particles to achieve the desired particle size distribution, thereby improving the bonding performance between the glass powder and the metal filler.

[0029] (2) Vacuum Drying: The wet-milled glass powder slurry is transferred to a vacuum drying apparatus, the zirconium balls are filtered out, and the glass powder is dried under a vacuum of 0.01 to 0.015 MPa. Acetone and moisture on the surface and inside of the glass powder particles are removed to obtain dry inorganic glass powder.

[0030] (3) Mechanical crushing: The vacuum-dried glass powder is mechanically crushed to further refine the particles for easy screening.

[0031] (4) Screening: The mechanically crushed glass powder is screened through a 500-mesh sieve to remove oversized particles and ensure the uniformity of the particle size of the glass powder to obtain the pretreated inorganic phase glass powder.

[0032] Furthermore, the preparation of the organic carrier includes:

[0033] (1) Raw material selection: at least one of ethyl cellulose, acrylic resin, and polyvinyl butyral resin and at least one of terpineol and diethylene glycol butyl ether acetate are selected to prepare the organic carrier;

[0034] (2) Colloid preparation: According to the formula requirements, add the resin powder prepared in the required proportion to an appropriate amount of solvent, and stir and dissolve it in an oil bath heated at 70°C. Optional auxiliary materials such as defoaming agents and dispersants can be added to ensure that all ingredients are fully mixed to form a colloid.

[0035] (3) Vacuum degassing: Place the prepared colloid into the vacuum degassing equipment, remove the bubbles in the colloid by stirring and vacuuming, improve the uniformity and stability of the colloid, and obtain an organic carrier.

[0036] A third aspect of the present invention provides use of the above-mentioned hole-filling slurry in a multi-layer wiring electrostatic chuck.

[0037] Furthermore, the electrostatic chuck has a hole diameter of 150 μm to 500 μm, a hole depth of 200 μm to 600 μm, and a maximum diameter-to-depth ratio of 2.5.

[0038] Beneficial effects:

[0039] (1) In the present invention, large-grained tungsten powder is used as the skeleton structure, and fine-grained tungsten powder is used to fill the pores, thereby playing a good supporting role. Molybdenum powder is used as the auxiliary conductive phase, and the melting point of molybdenum is lower than that of tungsten. It will form a liquid phase during the sintering process, wrapping the tungsten powder and forming good conductivity, thereby forming an efficient conductive network in the slurry.

[0040] (2) The inorganic glass powder adopts Al2O3-MgO-SiO2 system and is pre-treated by wet ball milling using high-purity acetone as the ball milling medium, so that the inorganic glass powder has uniform particle size, good slurry dispersion and good sintering fluidity.

[0041] (3) The present invention adjusts the sintering shrinkage, pore filling and conductivity of the slurry by adjusting the proportion of graded particle powder and regulating the proportion of conductive phase powder, organic carrier and inorganic glass powder, so as to meet the pore filling requirements of multi-layer electrostatic chucks with high depth, wide aperture and high aspect ratio. In addition, the pore filling slurry of the present invention can be used under conditions of high temperature and high pressure, ensuring good working stability and reliability of the chuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Attachment Figure 1 This is the front side of the chuck after filling the hole filling slurry prepared in Comparative Example 9.

[0043] Attachment Figure 2 The hole filling slurry prepared in Comparative Example 9 is on the back side of the hole filling chuck.

[0044] Attachment Figure 3 The hole filling slurry prepared in Example 6 is on the front side of the chuck after filling.

[0045] Attachment Figure 4 The back side of the chuck after filling the hole filling slurry prepared in Example 6. DETAILED DESCRIPTION

[0046] Specific embodiments of the present invention will be described in detail below, but the present invention is not limited to the embodiments including the following examples, and various modifications can be made within the scope that can achieve the object of the invention and does not depart from the gist of the invention.

[0047] In the following examples, unless otherwise specified, the raw materials, reagents or processing techniques used are all commercially available raw materials or conventional processing techniques commonly used in the art.

[0048] In order to solve the hole filling requirements of multi-layer wiring electrostatic chucks with high aspect ratio holes in the prior art, the present invention designs a unique hole filling slurry, which is composed of the following raw materials in parts by weight:

[0049] Conductive phase tungsten / molybdenum powder-graded particle mixed powder 80-88%;

[0050] Inorganic glass powder 3% to 10%;

[0051] Organic carrier 3% to 10%;

[0052] Additives 0.5% to 2.5%;

[0053] The sum of the mass percentages of the above components is 100%.

[0054] It mainly uses tungsten / molybdenum powder-graded particle mixed powder to pretreat the inorganic phase glass powder, while controlling the net content of the carrier colloid and supplemented with corresponding additives to make the viscosity of the prepared slurry range from 6000 to 15000 Pa.s. The internal system is stable and meets the needs of high depth and wide aperture filling.

[0055] <Conductive Phase Tungsten / Molybdenum Powder - Graded Particle Mixture>

[0056] The conductive tungsten / molybdenum powder-graded particle mixture of the present invention comprises tungsten powder and molybdenum powder of different particle sizes, with a mass ratio of tungsten powder to molybdenum powder of 7-8:3-2. The tungsten / molybdenum powder-graded particle mixture, as the conductive phase, provides excellent electrical conductivity. Tungsten powder is used as the main conductive component, and the particle size of the tungsten powder is in the range of 0.3-2 μm. It is formed by mixing two tungsten powders with different particle sizes. The two tungsten powders with different particle sizes are defined as a first tungsten powder and a second tungsten powder, respectively. The particle size of the second tungsten powder is selected from 1.0-2.0 μm, and specifically, any particle size of 1.0 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.8 μm, 1.9 μm, and 2.0 μm or within the range of any two of the above particle sizes; in the present invention, the minimum difference between the particle sizes of the first tungsten powder and the second tungsten powder is 0.5 μm, for example, the difference can be 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, or 0.9 μm. , 1.0μm, 1.1μm, 1.2μm, 1.3μm, 1.4μm, 1.5μm, 1.6μm, 1.7μm, etc. The first tungsten powder and the second tungsten powder are mixed in a mass ratio of 2~4:6~8. Since tungsten powder and molybdenum powder have different electrical conductivity and melting points, large-particle tungsten powder serves as a skeleton structure, and fine-particle tungsten powder fills the pores, playing a good supporting role. In the present invention, the sintering temperature reaches 1600-1700℃. The inventor unexpectedly discovered that during sintering, the molybdenum powder forms a liquid phase first before the tungsten powder with a higher melting point, thereby wrapping the tungsten powder during the sintering process, forming good conductivity, and thus forming an efficient conductive network in the slurry; the reason for this phenomenon may be that both particles are nanometer-level, and tungsten and molybdenum will first form an alloy structure, thereby greatly reducing the melting point, causing the molybdenum to melt and form a liquid phase. The particle size of the molybdenum powder used as auxiliary conductivity is selected from 0.3-2.0 μm, and specifically any particle size among 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1.0 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.8 μm, 1.9 μm, 2.0 μm or within the range of any two of the above particle sizes.

[0057] In the present invention, in order to achieve a better particle gradation conductive network, the particle size of the first tungsten powder is preferably 0.3-1.0 μm, and specifically any particle size among 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1.0 μm or within the range of any two of the above particle sizes;

[0058] In the present invention, there is no particular limitation on the shapes of the tungsten powder and the molybdenum powder. In the examples, spherical tungsten powder / molybdenum powder is used to prepare the hole-filling slurry.

[0059] Specifically, some embodiments of the present invention use two conductive phases and three particle size specifications of powder, and form tungsten / molybdenum powder-graded particle mixed powder through mixing, dry ball milling, and screening. The mixed powder structure is used to prepare the slurry, which can not only effectively prevent the oxidation and agglomeration of tungsten powder sintering, but also utilize the bridges between the graded particles to increase the conductive path, thereby improving the conductivity, stability, flexibility and applicability of the hole-filling slurry, and can meet the filling requirements of high depth, wide aperture and high aspect ratio.

[0060] In some embodiments of the present invention, the preparation of the conductive phase tungsten / molybdenum powder-graded particle mixed powder is as follows:

[0061] Spherical tungsten powders of two different particle sizes are mechanically premixed in the desired ratio. Spherical molybdenum powder is then mechanically premixed with the mixed tungsten powder in the desired ratio. The mixed powders are dry-milled in a horizontal ball mill using high-purity zirconia balls. The milling frequency is 12.5-17.5 Hz and the milling time is 12 hours. The milled powders are then sieved through a 150-mesh screen to obtain a conductive tungsten / molybdenum powder-graded particle mixture.

[0062] <Inorganic glass powder>

[0063] In the present invention, the inorganic glass powder is selected from the Al2O3-MgO-SiO2 system; wherein, the inorganic glass powder is obtained by pretreatment, and the pretreatment process includes wet ball milling, vacuum drying, mechanical crushing, and screening.

[0064] In some embodiments of the present invention, the raw materials for Al2O3-MgO-SiO2 system glass are weighed according to mass percentage: Al2O3 80%-90%, MgO 3%-10%, SiO2 3%-5%, and the sum of the mass percentages of the above components is 100%. The above materials are subjected to wet ball milling, vacuum drying, mechanical crushing, and screening to form inorganic phase glass powder.

[0065] Wet ball milling: Using Al2O3-MgO-SiO2 inorganic glass powder, high-purity acetone and 2mm diameter zirconia balls as the milling medium, wet milling is used to mix and refine the glass powder particles. A horizontal ball mill is used, with a milling frequency of 14.5-17.5 Hz and a milling time of 24 hours. This method uses high-purity acetone as the milling dispersion medium, which achieves better dispersion than traditional methods using water, ethanol, etc., resulting in an inorganic glass powder with improved dispersion and uniformity, thereby enhancing sintering performance.

[0066] Vacuum Drying: Transfer the wet-milled glass powder slurry to a clean tray, filter out the zirconium balls, and dry it under a vacuum of 0.01-0.015 MPa at 60-70°C for 4-6 hours. This vacuum drying process removes acetone and moisture from the surface and interior of the glass powder particles, resulting in dry inorganic glass powder.

[0067] Mechanical pulverization: The vacuum-dried glass powder is mechanically pulverized to further refine the particles for easier screening. A quartz mortar or particle crusher can be used for pulverization to avoid contamination by impurities.

[0068] Screening: The mechanically crushed glass powder is screened through a 1500 mesh screen to remove oversized particles, ensure the uniformity of the particle size of the glass powder, and obtain the pre-treated inorganic phase glass powder.

[0069] <Organic Carrier>

[0070] The organic phase carrier of the present invention includes a resin and a solvent, wherein the resin is selected from at least one of ethyl cellulose, acrylic resin, polyvinyl butyral resin, etc., and the solvent is selected from at least one of terpineol and diethylene glycol butyl ether acetate. The production and preparation process of the organic carrier of the present invention involves raw material selection, colloid configuration, and vacuum degassing.

[0071] Raw material selection: choose one or two of ethyl cellulose, acrylic acid, and polyvinyl butyral resin and mix them in the required proportion.

[0072] Colloid Preparation: According to the recipe requirements, add the resin powder prepared in the required proportions to an appropriate amount of solvent and stir to dissolve in an oil bath heated at 70°C. Add auxiliary materials such as defoamers and dispersants to fully mix the ingredients to form a colloid. The resin powder ratio can be adjusted as needed to obtain colloids with different properties.

[0073] Vacuum degassing: Place the prepared colloid into the vacuum degassing equipment, remove the bubbles in the colloid through planetary dispersion and vacuuming, improve the uniformity and stability of the colloid, and obtain the organic phase carrier.

[0074] In the present invention, the organic vehicle can be composed of the following components in mass percentage: 5% to 10% ethyl cellulose, 5% to 10% acrylic resin, 5% to 10% polyvinyl butyral resin, 30% to 40% terpineol, 20% to 25% diethylene glycol butyl ether acetate, 0.5% to 1% defoaming agent, and 0.5% to 1% dispersant. The sum of the mass percentages of the above components is 100%.

[0075] <Additives>

[0076] In the present invention, the auxiliary agent is selected from at least one of a dispersant, a defoaming agent, a solvent, and a thixotropic agent; the dispersant is selected from at least one of lecithin, tributyl citrate, and ethylene glycol diacetate; the thixotropic agent is selected from at least one of hydrogenated castor oil and polyamide wax; the defoaming agent is selected from at least one of polyethylene glycol, polyoxypropylene glycol ether, and glycerol fatty acid ester; and the solvent is selected from at least one of dibutyl phthalate, terpineol, and diethylene glycol butyl ether acetate.

[0077] <Preparation of Hole Filling Slurry>

[0078] Mixing ingredients: Add the prepared conductive phase tungsten / molybdenum powder-graded particle mixed powder, pretreated inorganic glass powder, organic carrier and auxiliary materials and additives into the mixing equipment in sequence according to the set mass percentage, and perform preliminary mixing to ensure that the components are initially evenly distributed.

[0079] Roller dispersion: finely mix the materials after preliminary mixing, and use three-roller grinding equipment to grind and disperse them multiple times to ensure sufficient contact and mixing between the components, thus ensuring the uniformity and stability of the pore-filling slurry.

[0080] Performance testing: The prepared hole-filling slurry is tested for performance, and the compatibility of the hole-filling process and sintering process is tested. Once qualified, the hole-filling slurry is packaged and stored in a cool, dry environment until ready for use.

[0081] Example

[0082] The present invention will be described in detail below with reference to specific embodiments. In the following examples, unless otherwise specified, the raw materials, reagents or processing techniques used are all commercially available raw materials or conventional processing techniques commonly used in the art.

[0083] In Examples 1-12 of the present invention, the inorganic glass powder is processed as follows: 100 g of inorganic glass powder of the Al2O3-MgO-SiO2 system (Al2O3 85%, MgO 10%, SiO2 5%) is wet-milled using high-purity acetone and 2 mm diameter zirconia balls as the milling media, using a horizontal ball mill, a milling frequency of 14.5 to 17.5 Hz, and a milling time of 24 hours; vacuum drying is performed under a vacuum degree of 0.01 to 0.015 MPa, a drying temperature of 60 to 70°C, and a drying time of 4 to 6 hours; the vacuum-dried glass powder is mechanically pulverized and sieved through a 1500 mesh screen to remove oversized particles and ensure the uniformity of the glass powder particle size, thereby obtaining pretreated inorganic phase glass powder.

[0084] In Examples 1-12 of the present invention, the preparation process of the organic vehicle is as follows: 45 g of ethyl cellulose, 45 g of acrylic resin, 70 g of terpineol, 135.5 g of diethylene glycol butyl ether acetate, 1.5 g of glycerol fatty acid ester as a defoamer, and 3 g of lecithin as a dispersant are mixed, heated in an oil bath at 70° C., dissolved by mechanical stirring, and vacuum degassing to obtain an organic vehicle;

[0085] In the embodiment of the present invention, the dispersant used in the preparation step of the hole-filling slurry is lecithin, the thixotropic agent is polyamide wax, and the mixed solvent is terpineol and diethylene glycol butyl ether acetate (mass ratio 1:2).

[0086] Example 1

[0087] 36.96 g of 0.5 μm tungsten powder, 147.84 g of 1.5 μm tungsten powder, and 79.2 g of 2 μm molybdenum powder were screened and processed to obtain a tungsten / molybdenum powder-graded particle mixed powder;

[0088] Take 264 grams of tungsten / molybdenum powder-graded particle mixed powder, 12 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0089] Example 2

[0090] 55.44 g of 0.5 μm tungsten powder, 129.36 g of 1.5 μm tungsten powder, and 79.2 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0091] Take 264 grams of tungsten / molybdenum powder-graded particle mixed powder, 12 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0092] Example 3

[0093] 72.38 g of 0.5 μm tungsten powder, 112.42 g of 1.5 μm tungsten powder, and 79.2 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0094] Take 264 grams of tungsten / molybdenum powder-graded particle mixed powder, 12 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0095] Example 4

[0096] 58.46 g of 0.5 μm tungsten powder, 136.54 g of 1.5 μm tungsten powder, and 69 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0097] Take 264 grams of tungsten / molybdenum powder-graded particle mixed powder, 12 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0098] Example 5

[0099] 62.27 g of 0.5 μm tungsten powder, 145.73 g of 1.5 μm tungsten powder, and 56 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0100] Take 264 grams of tungsten / molybdenum powder-graded particle mixed powder, 12 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0101] Example 6

[0102] Take 54.18g of 0.5μm tungsten powder, 126.42g of 1.5μm tungsten powder, and 77.4g of 2μm molybdenum powder, and mix them to obtain tungsten / molybdenum powder-graded particle mixed powder.

[0103] Take 258 grams of tungsten / molybdenum powder-graded particle mixed powder, 18 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a slurry suitable for filling holes with high diameter-to-depth ratio holes and multi-layer wiring chucks is obtained.

[0104] Example 7

[0105] 52.92 g of 0.5 μm tungsten powder, 123.48 g of 1.5 μm tungsten powder, and 75.6 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0106] Take 252 grams of tungsten / molybdenum powder-graded particle mixed powder, 24 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0107] Example 8

[0108] 51.66 g of 0.5 μm tungsten powder, 120.54 g of 1.5 μm tungsten powder, and 73.8 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0109] Take 246 grams of tungsten / molybdenum powder-graded particle mixed powder, 30 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0110] Example 9

[0111] 52.92 g of 0.5 μm tungsten powder, 123.48 g of 1 μm tungsten powder, and 75.6 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0112] Take 252 grams of tungsten / molybdenum powder-graded particle mixed powder, 24 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0113] Example 10

[0114] 52.92 g of 0.5 μm tungsten powder, 123.48 g of 2 μm tungsten powder, and 75.6 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0115] Take 252 grams of tungsten / molybdenum powder-graded particle mixed powder, 24 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0116] Example 11

[0117] 52.92 g of 1 μm tungsten powder, 123.48 g of 2 μm tungsten powder, and 75.6 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0118] Take 252 grams of tungsten / molybdenum powder-graded particle mixed powder, 24 grams of inorganic phase glass powder, 16.5 grams of organic carrier, 1.5 grams of dispersant, 3 grams of thixotropic agent, and 3 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0119] Example 12

[0120] 36.96 g of 0.3 μm tungsten powder, 155.04 g of 1.5 μm tungsten powder, and 48 g of 2 μm molybdenum powder were mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0121] Take 240 grams of tungsten / molybdenum powder-graded particle mixed powder, 30 grams of inorganic phase glass powder, 24 grams of organic carrier, 1 gram of dispersant, 2.5 grams of thixotropic agent, and 2.5 grams of mixed solvent, add them to the sample tank in sequence, stir evenly with a planetary mixer, and then use a three-roll mill to roll and disperse them. After completion, a high diameter-to-depth ratio hole and multi-layer wiring chuck filling slurry is obtained.

[0122] Comparative Example 1

[0123] The same as Example 7, except that no molybdenum powder is added in the preparation of the conductive phase in step 1: 75.78 grams of screened 0.5 μm tungsten powder and 176.22 grams of 1.5 μm tungsten powder are mixed to obtain a tungsten particle mixed powder.

[0124] Comparative Example 2

[0125] The same as Example 7, the only difference is that only one type of tungsten powder is used in the preparation of the conductive phase in step 1: 176.4 grams of screened 0.5 μm tungsten powder and 75.6 grams of 2 μm molybdenum powder are mixed to obtain a tungsten / molybdenum particle mixture.

[0126] Comparative Example 3

[0127] The same as Example 7, the only difference is that only one type of tungsten powder is used in the preparation of the conductive phase in step 1: 176.4 grams of screened 1.5 μm tungsten powder and 75.6 grams of 2 μm molybdenum powder are mixed to obtain a tungsten / molybdenum particle mixture.

[0128] Comparative Example 4

[0129] The same as Example 7, except that only molybdenum powder is used in the preparation of the conductive phase in step 1: 252 grams of screened 2 μm particle size molybdenum powder and 75.6 grams of 2 μm particle size molybdenum powder are mixed to obtain tungsten / molybdenum particle mixed powder.

[0130] Comparative Example 5

[0131] The same as Example 7, the only difference is that the particle size difference of the two tungsten powders is different: 52.92 grams of screened 0.9 μm tungsten powder, 123.48 grams of 1.2 μm tungsten powder, and 75.6 grams of 2 μm molybdenum powder are mixed to obtain tungsten / molybdenum powder-graded particle mixed powder.

[0132] Comparative Example 6

[0133] The same as Example 12, the only difference is that the particle size of the second tungsten powder is different: 52.92 grams of screened 0.3 μm tungsten powder, 123.48 grams of 0.8 μm tungsten powder, and 75.6 grams of 2 μm molybdenum powder are mixed to obtain tungsten / molybdenum powder-graded particle mixed powder.

[0134] Comparative Example 7

[0135] The same as Example 7, the only difference is that the particle size of the second tungsten powder is different: 52.92 grams of screened 0.5 μm tungsten powder, 123.48 grams of 2.5 μm tungsten powder, and 75.6 grams of 2 μm molybdenum powder are mixed to obtain tungsten / molybdenum powder-graded particle mixed powder.

[0136] Comparative Example 8

[0137] The same as Example 7, the only difference is the treatment of the inorganic glass powder: high-purity ethanol and 2 mm diameter zirconia balls are used as ball milling media for wet ball milling.

[0138] Comparative Example 9

[0139] The same as Example 7, except that the particle size of the second tungsten powder is different: 52.92 grams of screened 0.5 μm tungsten powder, 123.48 grams of 0.8 μm tungsten powder, and 75.6 grams of 2 μm molybdenum powder are mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0140] Comparative Example 10

[0141] The same as Comparative Example 6, the only difference is that the particle size of the second tungsten powder is different: 52.92 grams of screened 0.1 μm tungsten powder, 123.48 grams of 0.6 μm tungsten powder, and 75.6 grams of 2 μm molybdenum powder are mixed to obtain a tungsten / molybdenum powder-graded particle mixed powder.

[0142] test

[0143] The pore-filling slurry prepared in the above examples and comparative examples was printed onto a ceramic sheet having pores with a thickness of 500 μm and a pore size of 500 μm. The slurry was heated to 1500-1700° C. in a nitrogen-hydrogen mixed gas environment and kept at this temperature for 2 hours for sintering, followed by cooling.

[0144] <Conductivity performance test method>

[0145] Use a four-probe resistance tester to test the resistivity.

[0146] <Pore filling properties>

[0147] Determine the number of times the slurry needs to fill the hole. The evaluation criteria are as follows:

[0148] 2nd time: Excellent

[0149] 3 times: Good

[0150] 4 times: Passed.

[0151] <Sinterability>

[0152] The sintered ceramics are first cut to the pore-filling slurry, and a scanning electron microscope is used to observe whether there are pores between the pore-filling slurry and the ceramic.

[0153] Excellent: matches the shrinkage of ceramics, with no porosity at the joint;

[0154] Good: The slurry expands slightly and there are no pores at the joints;

[0155] Acceptable: The slurry shrinks slightly and there are no pores at the joints.

[0156] <Front side raised, back side sunken>

[0157] Use a 3D surface profiler to test the convex and concave data of the front and back sides.

[0158] Test results of implementation 1-12 and comparative example 1-10:

[0159] Serial number Pore ​​filling Sinterability Front convexity / μm Back side depression / μm Resistivity / Ω·cm Example 1 qualified good 7 5 2.2E-8 Example 2 good Excellent 4 4 2.1E-8 Example 3 qualified good 6 5 2.4E-8 Example 4 qualified Excellent 5 7 2.8E-8 Example 5 qualified good 6 6 3.2E-8 Example 6 Excellent Excellent 4 2 5.7E-8 Example 7 Excellent Excellent 1 1 6.2E-8 Example 8 qualified good 2 1 9.4E-8 Example 9 Excellent good 3 2 8.2E-9 Example 10 Excellent qualified 2 5 5.2E-8 Example 11 good good 7 4 8.9E-8 Example 12 Excellent good 3 4 7.5E-8 Comparative Example 1 good Difference 5 3 5.9E-6 Comparative Example 2 qualified Difference 3 8 7.1E-9 Comparative Example 3 good Difference 7 5 2.2E-7 Comparative Example 4 Difference good 9 24 4.1E-9 Comparative Example 5 Excellent qualified 4 2 8.3E-7 Comparative Example 6 good Excellent -8 19 8.2E-9 Comparative Example 7 good Difference 5 2 8.3E-6 Comparative Example 8 Excellent Difference 2 3 4.5E-3 Comparative Example 9 good qualified -7 5 9.5E-7 Comparative Example 10 good Difference -13 9 6.2E-9

[0160] The above results show that the use of tungsten-molybdenum particle-grade conductive phase, combined with the inorganic glass powder and organic vehicle used in the present invention, to produce high-aspect-ratio holes and multi-layer wiring chuck hole filling slurries meets the requirements for hole filling, sintering, front-side protrusion after sintering, and back-side depression. Comparative Example 1, which uses only two tungsten powder particle sizes, has poor sintering performance and increased resistivity, resulting in poor conductivity of the slurry. Comparative Examples 2 and 3, which only use one type of tungsten powder, also exhibit poor sintering performance. Comparative Example 4, which uses only molybdenum powder, performs poorly in hole filling performance and has particularly severe back-side depression, resulting in insufficient interlayer conductivity after sintering.

[0161] Although the comparative example 5 meets the tungsten and molybdenum particle grading, the particle size difference between the two tungsten powder particles is less than 0.5 μm, which is reflected in the increase in the resistivity of the slurry and affects the conductivity of the chuck. The particle size of the tungsten powder in comparative examples 6, 9, and 10 is less than 1 μm, and there are no tungsten powder particles as a skeleton. After filling the chuck, the slurry still has serious backside depression; at the same time, Figure 1 and Figure 2 It can also be seen that due to the lack of tungsten powder with a particle size larger than 1μm as a supporting framework, significant depressions are present on both the front and back surfaces, resulting in severely insufficient interlayer conductivity after sintering after hole filling. Comparative Example 7 uses tungsten powder with a particle size larger than 2μm, and Comparative Example 8 uses high-purity ethanol instead of acetone. The resistivity of the slurry increases and the sintering performance deteriorates. This is likely due to the large tungsten powder particle size and the uneven dispersion of the inorganic glass powder particles, resulting in poor uniformity in the prepared hole-filling slurry.

[0162] The above description is only a preferred specific embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Any simple change or equivalent replacement of the technical solution that can be obviously obtained by any technician familiar with this technical field within the technical scope disclosed in the present invention falls within the scope of protection of the present invention.

Claims

1. A hole filling slurry for a multi-layer wiring chuck, characterized in that: The invention comprises a conductive phase powder, an inorganic glass powder, an organic carrier and an additive; the conductive phase powder is composed of tungsten powder and molybdenum powder, and the particle size of the conductive phase powder is selected from 0.3-2.0 μm; the tungsten powder is composed of a first tungsten powder and a second tungsten powder, and the particle size of the second tungsten powder is selected from 1.0~2.0 μm, and the particle sizes of the first tungsten powder and the second tungsten powder differ by at least 0.5 μm.

2. The hole-filling slurry according to claim 1, characterized in that: In the conductive phase powder, the mass of tungsten powder: the mass of molybdenum powder = 7-8:3-2; the mass ratio of the first tungsten powder to the second tungsten powder is 2-4:6-8.

3. The hole-filling slurry according to claim 1, characterized in that: The pore filling slurry is composed of the following components in percentage by mass: Conductive phase powder 80-88%; Inorganic glass powder 3% to 10%; Organic carrier 3% to 10%; Additives 0.5%~2.5%.

4. The hole-filling slurry according to claim 1, characterized in that: The particle size of the first tungsten powder is selected from 0.3 to 1.0 μm.

5. The pore-filling slurry according to any one of claims 1 to 4, characterized in that: The organic carrier comprises a resin and an organic solvent, wherein the resin is selected from at least one of ethyl cellulose, acrylic resin, and polyvinyl butyral resin; and the organic solvent is selected from at least one of terpineol and diethylene glycol butyl ether acetate.

6. The pore-filling slurry according to any one of claims 1 to 4, characterized in that: The inorganic glass powder is Al2O3-MgO-SiO2 system.

7. The hole-filling slurry according to claim 6, characterized in that: The inorganic glass powder is obtained through pretreatment, wherein the pretreatment includes wet ball milling, and the ball milling medium is high-purity acetone and zirconia balls with a diameter of 2 mm.

8. The hole-filling slurry according to claim 7, characterized in that: The auxiliary agent is selected from at least one of a dispersant, a defoaming agent, a solvent, and a thixotropic agent; the dispersant is selected from at least one of lecithin, tributyl citrate, and ethylene glycol diacetate; the thixotropic agent is selected from at least one of hydrogenated castor oil and polyamide wax; the defoaming agent is selected from at least one of polyethylene glycol, polyoxypropylene glycol ether, and glycerol fatty acid ester; and the solvent is selected from at least one of dibutyl phthalate, terpineol, and diethylene glycol butyl ether acetate.

9. A method for preparing the pore-filling slurry according to any one of claims 1 to 8, characterized in that: The preparation process includes the following: Ingredient mixing step: Add the prepared conductive phase powder, pretreated inorganic glass powder, organic carrier and additives in the mixing equipment in the set mass percentage and perform preliminary mixing; Rolling dispersion step: finely mix the preliminarily mixed materials, use a three-roll mill, and grind and disperse them multiple times to ensure that the components are fully contacted and mixed to obtain a pore-filling slurry.

10. Use of the hole filling slurry according to any one of claims 1 to 8 in a multi-layer wiring electrostatic chuck, characterized in that: The electrostatic chuck has a hole diameter of 150 μm to 500 μm and a hole depth of 200 μm to 600 μm.

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