CN111081626A - Electrostatic chuck containing high-resistance ceramic hot-melt injection material - Google Patents
Electrostatic chuck containing high-resistance ceramic hot-melt injection material Download PDFInfo
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- CN111081626A CN111081626A CN201911411347.4A CN201911411347A CN111081626A CN 111081626 A CN111081626 A CN 111081626A CN 201911411347 A CN201911411347 A CN 201911411347A CN 111081626 A CN111081626 A CN 111081626A
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- dielectric layer
- electrostatic chuck
- yag
- layer
- resistance ceramic
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
- H01L21/6831—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using electrostatic chucks
- H01L21/6833—Details of electrostatic chucks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32431—Constructional details of the reactor
- H01J37/32715—Workpiece holder
Abstract
The invention provides an electrostatic chuck containing high-resistance ceramic hot-melt injection material, which sequentially comprises a metal base material, a dielectric layer, a conductive electrode layer and an upper dielectric layer from bottom to top, wherein the lower dielectric layer or the upper dielectric layer is made of Al subjected to melt injection filtering treatment2O3-YAG composite acidizing substance powder. The invention can increase the uniform adsorption force of the electrostatic chuck, shorten the separation time and prolong the service life.
Description
Technical Field
The invention belongs to the field of electrostatic chucks of cores in semiconductor/display screen manufacturing devices, and particularly belongs to Al2O3-YAG based materials for the insulating layer and the dielectric layer.
Background
Recently, as semiconductor and display panel manufacturing engineering techniques tend to increase the size of silicon wafers or glass substrates (hereinafter referred to as objects to be processed), circuits have been highly concentrated, and processing has been made ultra-fine; in the film evaporating and etching engineering which is the trend of the plasma etching engineering and other technologies, the fixing method of the processed object is greatly changed. The conventional method of mechanically clamping or fixing the object to be processed using a vacuum chuck is gradually eliminated, and the semiconductor/display screen panel engineering equipment in the last half century uses static electricity as a core part of the chuck.
The electrostatic chuck is composed of two or more dielectric layers (or electrical insulating layers) and a conductive electrode layer interposed between the dielectric layers, and the conductive electrode layer is a device that applies a dc voltage to the conductive electrode layer, and causes an object to be processed to have an opposite polarity by a polarization phenomenon of the dielectric, and then causes an attractive force between the object and the dielectric. The electrostatic chuck is in full contact with the object to be processed to generate strong and uniform static electricity, ensure the smoothness of the surface of the object to be processed, control the temperature and minimize the generation of pollution particles. According to the types of dielectric layers on the upper part of the electrostatic chuck, the electrostatic chuck has two-stage acidification type, resin type and ceramic film type, and the three electrostatic chucks have the advantages of high durability and long service life.
In the conventional ceramic thin film connection type electrostatic chuck, the base material is a ceramic insulating thin film, and the conductive electrode thin film, the conductive electrode, and the ceramic dielectric thin film are connected in this order, and the manufacturing cost is extremely high. However, if the components are connected by a polymer resin or a silicate compound. The ceramic of the connection layer here has a relatively low dielectric and plasma resistance or has a low thermal conductivity, and fracture of the connection layer may occur under high voltage application for a long time. In addition, the adhesive is used in a manner that the ceramic is processed to a thickness of 100 to 1000 μm, so that the electrostatic chuck is not suitable for use in flat panel manufacturing of large-diameter semiconductor wafers.
In order to solve the problems of the conventional ceramic thin film connection type electrostatic chuck, a more preferable technique is required for manufacturing a core component of the electrostatic chuck, and a proposal has been made to use a dielectric and an electrode layer for heat-fusion filtering, and to use Al for improving static electricity from the aspect of a dielectric material2O3-TiO2Is a ceramic. However, Al used for the electrostatic chuck2O3-TiO2The fuse-injection filter layer has a small volume and a fixed resistance, and thus causes a high leakage current when a voltage is applied, and its characteristics are deteriorated when the application is interrupted.
Al used for conventional electrostatic chuck2O3Compared with sintered ceramic materials, the hot-melt injection filter layer has the defect of high porosity. The formation of voids and defects in the thermal-spray filter layer is mainly caused by the coagulation and shrinkage of molten droplets after mixing of non-molten particles, and a local region having a size of several tens of μm is isolated. Some particles will be connected to form a 3-dimension net structure in the filter layer. FIG. 2 shows a plasma used for the electrostatic chuckMelt-blown Al2O3The fine structure of the filter layer in the cross-sectional view produced pores having a size of about 5 to 15 μm and arranged in disorder. Generally, the porosity is generally 1 to 2% as measured by a method of measuring the porosity by a display analysis at a magnification of 200 times. However, Al observed at a high magnification (1000 times) was used2O3As shown in fig. 3, in the thermal fuse filter layer, thin pore layers exist at the interfaces between the laminated particles other than the pores which are not too large as seen in fig. 2, and fine pores are formed in the laminated particles. These gas-porous layers and the filter layers interconnecting the fine pores create a 3-dimensional network of defective bonds.
Al mentioned above2O3The mesh structure of the pores of the melt-injection filter layer plays a role in conducting a circuit due to the invasion of electronic pollutants. Here, since the contaminant includes charge-various particles and moisture in the atmosphere and the electrostatic chuck in the apparatus contains plasma particles, Al has been conventionally used2O3After high voltage is applied to a ceramic filtering electrostatic chuck formed by fusion jetting, Al2O3Because the dielectric layer adds relatively low dielectric breakdown voltage contaminants; the leakage current increases, eventually leading to the problem of static electricity dissipation. In order to prevent the filter layer from being contaminated by the contaminants from the outside, an organic or inorganic adhesive is injected into the filter layer, thereby increasing the resistance to static electricity. However, it is difficult to completely remove the adhesive after injecting the adhesive into the pores of the filter layer, and the adhesive and Al are mixed2O3In contrast, excessive use of the adhesive reduces static electricity, durability, and lifetime of the electrostatic chuck.
Disclosure of Invention
The purpose is as follows: the problems of static electricity, durability and service life shortening of the electrostatic chuck in the prior art are solved; the invasion of external pollutants.
The technical scheme is as follows: an electrostatic chuck containing high-resistance ceramic thermal spray material comprises a metal base material, a bottom dielectric layer, a conductive electrode layer and an upper dielectric layer from bottom to top in sequence, wherein the lower dielectric layer or the upper dielectric layer is made of Al processed by thermal spray filtering2O3-YAG composite acidizing substance powder.
Further, the above-mentioned Al2O3The YAG composite acid compound is composed of 5-95 wt% of YAG and 5-95 wt% of Al2O3And (5) manufacturing.
Further, the thickness of the dielectric layer of the Al2O3-YAG based thermal injection filter layer is 100 to 1000 μm.
Further, one or more than 1 of the surfaces of the upper dielectric layer or the lower dielectric layer is sealed by a liquid organic or inorganic processing liquid, and the processed dielectric layer has a size of 1 × 1015A volume resistivity of not less than Ω · cm and a dielectric breakdown voltage of not less than 30 kV/mm.
Further, by containing the above-mentioned Al2O3Spraying a mixture of YAG powder and powder to dry the mixture to 5-100 μm Al2O3-YAG composite acid powder.
Has the advantages that: al having very high volume resistivity and dielectric breakdown voltage produced by thermal spray coating2O3The application of YAG-series coatings to the lower and upper insulating dielectric layers of the electrostatic chuck increases the durability of the electrostatic chuck and greatly improves its service life.
Further, the electrostatic chuck dielectric layer Al constituted by the present invention2O3The YAG series spray coating forms a pore network to inhibit the generation of channels, thereby inhibiting the invasion of external foreign matters and minimizing the use amount of silicate.
Drawings
Fig. 1 is a general configuration diagram of a cross-sectional view of an electrostatic chuck of the present invention.
FIG. 2 shows plasma-fused Al used in an electrostatic chuck2O3The microscopic structure is shown magnified 200 times in the coating cross-section.
FIG. 3 shows plasma-fused Al used in an electrostatic chuck2O3The microscopic structure is shown at 100 times magnification of the coating cross section.
FIG. 4 shows Al in an example of the present invention2O3Fine texture shown by 1000 times magnification of the coating cross section of the YAG series.
In fig. 1: 10 is an electrostatic chuck, 1 is a metal base material, 2 is a bottom coating layer, 3 is a bottom dielectric layer, 4 is a conductive electrode layer, 5 is an upper dielectric layer, 6 is a wafer, and 7 is a direct current power supply.
Detailed Description
Hereinafter, the present invention will be described in detail by way of examples. The following examples are not intended to limit the scope of the present invention.
Preparation example: al (Al)2O3Production of YAG composite acidified powder
Example (b): method for manufacturing electrostatic chuck
Example 1:
an electrostatic chuck structure as shown in fig. 1 is manufactured, which comprises a metal base material 1, a lower dielectric layer 3, a conductive electrode layer 4 and an upper dielectric layer 5 from bottom to top, wherein the lower dielectric layer or the upper dielectric layer is made of Al2O3-YAG composite acid compound powder which is subjected to a melting and filtering treatment.
One surface of the base metal 1 (100 mm wide. 100m long. 5mm thick) was made of #100 Al2O3The particles are coated to have a surface roughness (Ra: 2 to 3 μm), and the above-mentioned production examples are produced from the entire surfaces thereof, using four kinds of different Al2O3Forming 250 μm Al by atmospheric coating and spray coating of YAG composite acid powder2O3-a YAG series insulating layer, i.e. a lower dielectric layer. By coating the Al in the atmosphere by a thermal spraying method2O3A50 mm X50 mm area partial conductive electrode layer 4 was formed on the surface of a YAG-based silicate layer, an Al2O 3-YAG-based insulating layer, i.e., an upper dielectric layer, was formed in a thickness of 250 μm on the lower dielectric layer 3 and the conductive electrode layer 4 by an atmospheric coating and thermal spraying method, and the thermal sprayed silicate layer was not subjected to a coating treatment.
Wherein Al is2O3YAG composite acid powder was prepared by a known dry spray technique, and the average particle size was 35 μm, and the weight ratio is shown in Table 1.
TABLE 1 powder composition and particle size of the examples
| Serial number | Al2O3: YAG weight ratio | Average particle diameter (μm) |
| Formulation 1 | 17:83 | 35 |
| |
50:50 | 35 |
| |
75:25 | 35 |
| |
90:10 | 35 |
In contrast, the dielectric layer and the conductive electrode layer were formed in the same manner, and Al was used for forming the dielectric layer2O3The meltallizing powder replaces Al with the purity of 99.9 percent2O3-YAG composite acid compound powder to form an upper dielectric layer and a lower dielectric layer having the same thickness.
The test pieces are respectively manufactured according to the formulas 1-4 and the formula of the comparison scheme, then the volume inherent resistance value is calculated after the direct current voltage is applied between the aluminum base material and the coating, then the printing voltage is increased by 0.5KV unit, and the insulation breakdown voltage of the coating is measured. Table 2 shows the results of the above experiments.
Table 2 comparison of electrical insulation properties of example 1
As can be seen from the results shown in Table 2, the Al of the present invention was obtained regardless of the measurement conditions2O3YAG series coatings with previous Al2O3Compared with the surface coating, the surface coating has 1000 times of high volume inherent impedance and high dielectric breakdown voltage.
Both coatings have very sensitive moisture insulating properties, in particular Al2O3Coatings, even with voltages as low as 1.5kV/mm, can cause very large electrical leakage. That is, Al is shown in FIGS. 2 and 32O3The coating contains a large number of fine pore networks/reticular structures which play a role of conducting paths for the water soaked around.
On the other hand, Al2O3The YAG series coatings reported in Table 1 are based on a network of pores/networks that maintain high breakdown voltage even in high humidity environments. FIG. 4 shows the microstructure of Al2O3-YAG series coating of formulation 2 at 1000 times magnification.
Example 2:
an organic liquid sealant was applied to the surface of the upper dielectric layer formed in example 1, and then the upper dielectric layer was heated at 150 ℃ for 3 hours in a vacuum state to perform sealing treatment, thereby forming the same dielectric layer and conductive electrode layer as in example 1.
Table 3 shows a comparison of the electrical insulation properties of the sealing treatment example 2.
Table 3 example 2 comparison of electrical insulation
Conventional Al2O3The plasma coating is sealed to greatly increase the volume inherent impedance and the dielectric breakdown voltage thereof, and the Al of the invention is not sealed after the sealing treatment2O3The higher intrinsic resistance and dielectric breakdown voltage is shown compared to YAG series coatings. On the other hand, Al of examples of the present invention2O3The coating compositions of the YAG series are shown in Table 1, and all of them have a very high volume intrinsic impedance of 1X 1015Ω · cm, and a dielectric breakdown voltage of more than 44 kV/mm.
Example 3:
examples Al according to the invention according to examples 1 and 22O3YAG series plasma coating with conventional Al2O3Plasma coated electrostatic chucks have better electrical insulating properties than plasma coated electrostatic chucks. Therefore, a direct current voltage can be applied to the metal electrode rod, and the number of processes (width 100 mm. times. length 120mm) for processing the electrostatic chuck base material, in which the bottom coat layer on the upper portion, the lower insulating dielectric layer, the conductive electrode layer, and the upper insulating layer are sequentially accumulated by a plasma fusion method, can be greatly reduced. At this time, the coating area of the conductive electrode layer was 80mm × 100 mm. The metal electric shock rod is directly connected with the middle conductive electrode layer, the periphery of the metal electric shock rod is made of the same material as the lower insulating dielectric medium, and the metal electric shock rod is insulated from the base material. The thickness of the bottom coating is 100 μm, the material is Ni, the thickness of the conductive electrode layer is 50 μm, the material is W, and the thicknesses of the lower insulating dielectric layer and the upper insulating dielectric layer are 500 μm respectively. Comparative example lower and upper insulating dielectric layers of Al having a purity of 99.9 wt%2O3The composition of this example is Al used in formulation 22O3-YAG composite acid powder (Al)2O3: YAG weight ratio of 50:50, average particle diameter of 35 μm) was formed into Al by a plasma spray method2O3YAG series 400 μm thick coating. After the plasma coating was completed, the upper dielectric layer was coated with an epoxy resin, and then heated at 150 ℃ in vacuum for 3 hours to perform a sealing treatment.
In this example, in order to evaluate the electrical characteristics of the electrostatic chuck manufactured as described above under different voltages, a dc voltage of 0.5 to 5.0kV was applied to a metal torch in the atmosphere for 60 seconds, and the leakage current and insulation resistance of the electrostatic chuck were measured.
TABLE 4
Former Al2O3The leakage current sharply increases with an increase in the applied voltage, and dielectric breakdown occurs at an applied voltage of about 3.1kV, in which the plasma sealing layer includes an electrostatic chuck. On the other hand, Al of the present invention is used2O3-YAG series coating electrostatic chuck, showing a constant applied voltage of Al2O3Compared with the electrostatic chuck, the insulation resistance of the electrostatic chuck is more than 5 times higher, and the leakage current is greatly increased along with the increase of the applied voltage. Further, the above-mentioned Al2O3The YAG series coating is applied with an electrostatic chuck, and the insulating dielectric layer is not damaged by applying 5.0kV direct current voltage for more than 10 minutes.
Example 4:
based on the characteristics of the electrostatic chuck of example 3, an electrostatic chuck for display device of actual size (1950 mm in width × 2150mm in length) was manufactured in the same manner as in example 3, and the electrical insulation characteristics of the electrostatic chuck were evaluated.
Conventional Al2O3The hot-melt spray coating is suitable for an electrostatic chuck, and the leakage current is greatly increased along with the increase of the applied voltage. When discharge occurs at an applied voltage in the range of 1 to 3kV, the electrostatic chuck function is lost due to dielectric breakdown. In another aspect, Al of the invention2O3The YAG series coating is applied to an electrostatic chuck, and the glass substrate is fixed by static electricity under the applied voltage of 2.5-3.0 kV, and the leakage current generated in the range does not generate insulation breakdown.
Claims (5)
1. An electrostatic chuck containing high-resistance ceramic hot-melt injection material comprises a metal base material (1), a lower dielectric layer (3), a conductive electrode layer (4) and an upper dielectric layer (5) from bottom to top in sequence, wherein the lower dielectric layer (3) or the upper dielectric layer (5) are respectively made of Al subjected to melt injection filtering treatment2O3-YAG composite acidizing substance powder.
2. The electrostatic chuck comprising a high resistance ceramic hot melt ejection material of claim 1, wherein: the Al is2O3The thickness of the dielectric layer of the YAG-based thermal-injection filter layer is 100 to 1000 μm.
3. The electrostatic chuck comprising a high resistance ceramic hot-melt ejection material according to claim 1 or 2, wherein: the Al is2O3The YAG composite acid compound is composed of 5-95 wt% of YAG and 5-95 wt% of Al2O3And (5) manufacturing.
4. The electrostatic chuck comprising a high resistance ceramic hot-melt ejection material according to claim 1 or 2, wherein: one or more than 1 surface of the upper dielectric layer or the lower dielectric layer is sealed by liquid organic or inorganic processing liquid, and the processed dielectric layer has a size of 1 × 1015A volume resistivity of not less than Ω · cm and a dielectric breakdown voltage of not less than 30 kV/mm.
5. The electrostatic chuck comprising a high resistance ceramic hot melt ejection material of claim 1, wherein: the Al is2O3-YAG composite acid powder is Al2O3Spray drying the mixed solution of the YAG powder and the powder to obtain Al with the size of 5-100 mu m2O3-YAG composite acid powder.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911411347.4A CN111081626A (en) | 2019-12-31 | 2019-12-31 | Electrostatic chuck containing high-resistance ceramic hot-melt injection material |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911411347.4A CN111081626A (en) | 2019-12-31 | 2019-12-31 | Electrostatic chuck containing high-resistance ceramic hot-melt injection material |
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| CN111081626A true CN111081626A (en) | 2020-04-28 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959547A (en) * | 2022-05-30 | 2022-08-30 | 苏州众芯联电子材料有限公司 | Process for increasing the compactness of a dielectric layer of an electrostatic chuck, process for manufacturing an electrostatic chuck, electrostatic chuck |
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| US20030007308A1 (en) * | 2000-01-21 | 2003-01-09 | Yoshio Harada | Electrostatic chuck member and method of producing the same |
| CN105980331A (en) * | 2014-03-10 | 2016-09-28 | 住友大阪水泥股份有限公司 | Dielectric material and electrostatic chucking device |
| CN108495829A (en) * | 2016-01-27 | 2018-09-04 | 住友大阪水泥股份有限公司 | Ceramic material and electrostatic chuck apparatus |
| CN109680241A (en) * | 2019-02-26 | 2019-04-26 | 中国科学院上海硅酸盐研究所 | It is tough, thermally conductive to stablize integrated amorphous oxides ceramic composite coating preparation method with high temperature micro-structure |
-
2019
- 2019-12-31 CN CN201911411347.4A patent/CN111081626A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030007308A1 (en) * | 2000-01-21 | 2003-01-09 | Yoshio Harada | Electrostatic chuck member and method of producing the same |
| CN105980331A (en) * | 2014-03-10 | 2016-09-28 | 住友大阪水泥股份有限公司 | Dielectric material and electrostatic chucking device |
| CN108495829A (en) * | 2016-01-27 | 2018-09-04 | 住友大阪水泥股份有限公司 | Ceramic material and electrostatic chuck apparatus |
| CN109680241A (en) * | 2019-02-26 | 2019-04-26 | 中国科学院上海硅酸盐研究所 | It is tough, thermally conductive to stablize integrated amorphous oxides ceramic composite coating preparation method with high temperature micro-structure |
Non-Patent Citations (1)
| Title |
|---|
| KAI YANG ET.AL.: "In-Situ fabrication of amorphous/eutectic Al2O3-YAG ceramic composite coating via atmospheric plasma spraying", 《JOURNAL OF THE EUROPEAN CERAMIC SOCIETY》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959547A (en) * | 2022-05-30 | 2022-08-30 | 苏州众芯联电子材料有限公司 | Process for increasing the compactness of a dielectric layer of an electrostatic chuck, process for manufacturing an electrostatic chuck, electrostatic chuck |
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Application publication date: 20200428 |