Metal plate frame and fluororubber sealing assembly and preparation method thereof

Abstract

The invention provides a metal plate frame and fluororubber sealing assembly and a preparation method thereof, and the preparation method is applied to the technical field of semiconductor sealing and comprises the steps that S1, a metal plate frame is coated with an adhesive, dried and then cooled, and the adhesive is a trithiocyanuric acid derivative solution; s2, a cross-linking agent and an addition agent are added in the thin-passing mixing process of the perfluoroether elastomer, a mixed rubber compound is obtained, the addition agent comprises fluorinated silicon dioxide, fluorinated titanium dioxide or PFA micro powder, and the mass of the addition agent is 2-10% of the mass of the perfluoroether elastomer; and S3, the mixed rubber sheet is placed in a metal plate frame, the metal plate frame with the mixed rubber sheet is placed in a mold to be subjected to hot pressing vulcanization forming, then secondary vulcanization is conducted, then radiation vulcanization is conducted, and the assembly is obtained. The assembly prepared through the method is resistant to plasma etching and high in cleanliness, the bonding performance of the perfluoroether rubber and the metal plate frame is good, and the rate of finished products is high.

Description

Technical Field

[0001] The present application relates to the field of semiconductor sealing technology, and in particular to a metal plate frame and fluororubber sealing assembly and a preparation method thereof. Background Art

[0002] Semiconductor manufacturing uses a variety of sealed clean process chambers designed to avoid contaminants that may affect the quality of the final manufactured products, such as semiconductor wafers and chips. Such process chambers include gates and valves, such as slit valves, to isolate the chamber from the surrounding environment. Such doors usually include a metal sheet frame and a sealing gasket cross-linked with the metal sheet frame. The material used to prepare such a sealing gasket is usually made of fluoropolymer or fluoroelastomer material, and in some cases, for highly contamination-resistant seals, it is made of perfluoroether rubber material. Such doors are commonly used in process reaction chambers in semiconductor manufacturing processes to open and close the chamber.

[0003] Perfluoroether rubber (FFKM) materials have chemical resistance, plasma resistance, and acceptable compression set and mechanical properties. Therefore, perfluoroether rubber materials are widely used. FFKM is usually prepared from perfluoromonomers, including at least one vulcanization site monomer, which forms a perfluoroether elastomer containing vulcanization sites after polymerization. A typical FFKM rubber composition includes the above-mentioned perfluoroether elastomer, a crosslinking agent, and the required filler.

[0004] The inertness of perfluoroether rubber compositions has the advantage of being used in harsh and clean environments, but due to their low surface energy, it is difficult to achieve sufficient strength and durability of bonding to metal sheet frame surfaces with higher surface energy.

[0005] Based on this, a new technical solution is needed. Summary of the invention

[0006] In view of this, the embodiments of this specification provide a method for preparing a metal plate frame and perfluoroether rubber sealing assembly to improve the bonding performance between the perfluoroether rubber and the metal plate frame.

[0007] This specification provides the following technical solution: A method for preparing a metal plate frame and fluororubber sealing assembly, comprising: S1. Applying adhesive to the bonding position between the metal plate frame and the perfluoroether rubber, drying and cooling, wherein the adhesive is a solution of a thiocyanate derivative; S2. A crosslinking agent and a filler are added to the perfluoroether elastomer during the thin-pass mixing process to obtain a mixed rubber, wherein the filler comprises fluorinated silicon dioxide, fluorinated titanium dioxide or PFA powder, and the mass of the filler is 2-10wt% of the mass of the perfluoroether elastomer; the vulcanization point monomer used in the perfluoroether elastomer is nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer is 1.5-3wt% of the mass of the perfluoroether elastomer; S3, placing the mixed rubber sheet in a metal plate frame, placing the metal plate frame with the mixed rubber sheet in a mold for hot pressing and vulcanization, taking out the metal plate frame, cleaning the burrs, performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly.

[0008] Optionally, in S1, the metal plate is coated after being subjected to mechanical treatment, solvent cleaning and degreasing, and plasma treatment in sequence, and the mechanical treatment includes frosting treatment and sandblasting treatment.

[0009] Optionally, the metal sheet frame is made of aluminum-magnesium alloy 6061.

[0010] Optionally, in S1, the solution concentration of the thiocyanate derivative is 2-6 wt %.

[0011] Optionally, in S1, the thiocyanate derivatives include sodium-based, amino-based and alkenyl-based compounds.

[0012] Optionally, in S1, the solvent in the thiocyanuric acid derivative solution is ethanol, methanol or isopropanol.

[0013] Optionally, in S1, the drying temperature is 50-100°C, and the drying time is 8-15 min.

[0014] Optionally, in S2, the crosslinking agent is tetraphenyltin or hexacyclooctadecane, the tetraphenyltin is 0.3-0.5 wt% of the mass of the perfluoroether elastomer, and the hexacyclooctadecane is 0.5-1 wt% of the mass of the perfluoroether elastomer.

[0015] Optionally, in S3, the hot pressing vulcanization molding conditions are 140-160°C×10-20 min.

[0016] Optionally, in S3, the vulcanization conditions of the secondary vulcanization are 180-220° C.×4-12 hr.

[0017] Optionally, in S3, the radiation dose of the radiation vulcanization is 30-100 kGy.

[0018] The present application also provides a metal plate frame and fluororubber sealing assembly, which is prepared using the above-mentioned preparation method.

[0019] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects: The preparation method of the present application improves the bonding performance of the perfluoroether rubber and the metal plate frame of the sealing assembly under high-cleanliness plasma etching resistance conditions and the yield rate of the sealing assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the method flow of this application. DETAILED DESCRIPTION

[0022] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0023] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0024] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0025] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the examples can be practiced without these specific details.

[0026] Semiconductor manufacturing uses a variety of sealed cleanroom process chambers designed to avoid contaminants that could affect the quality of final manufactured products such as semiconductor wafers and chips. Such process chambers include gates and valves, such as slit valves, to isolate the chamber from the surrounding environment. Such doors typically include a metal sheet frame and a sealing gasket that is cross-linked to the metal sheet frame. The materials used to make such sealing gaskets are typically made of fluoropolymers or fluoroelastomers, and in some cases, perfluoroether rubber materials for highly contamination-resistant seals. Such doors are commonly used in process reaction chambers during semiconductor manufacturing to open and close the chamber.

[0027] Perfluoroether rubber (FFKM) materials have chemical resistance, plasma resistance, and acceptable compression set resistance and mechanical properties. Therefore, perfluoroether rubber materials are widely used. FFKM is usually prepared from perfluoromonomers, including at least one vulcanization site monomer, which forms a perfluoroether elastomer containing vulcanization sites after polymerization. A typical FFKM rubber composition includes the above-mentioned perfluoroether elastomer, a crosslinking agent, and the required filler.

[0028] The inertness of perfluoroether rubber compositions has the advantage of being used in harsh and clean environments, but due to their low surface energy, it is difficult to achieve sufficient strength and durability of bonding to metal sheet frame surfaces with higher surface energy.

[0029] Based on this, the present specification proposes a method for preparing a metal plate frame and a fluororubber sealing assembly: Figure 1 Shown, including S1. Applying adhesive to the bonding position between the metal plate frame and the perfluoroether rubber, drying and cooling, wherein the adhesive is a solution of a thiocyanate derivative; S2. A crosslinking agent and a filler are added to the perfluoroether elastomer during a thin mixing process to obtain a mixed rubber, wherein the filler comprises fluorinated silicon dioxide, fluorinated titanium dioxide or PFA powder, and the mass of the filler is 2-10 wt % of the mass of the perfluoroether elastomer; the vulcanization point monomer used in the perfluoroether elastomer is nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer is 1.5-3 wt % of the mass of the perfluoroether elastomer; S3, placing the mixed rubber sheet in a metal plate frame, placing the metal plate frame with the mixed rubber sheet in a mold for hot pressing and vulcanization, taking out the metal plate frame, cleaning the burrs, performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly.

[0030] In S1, the metal plate frame is coated after mechanical treatment, solvent cleaning and degreasing, and plasma treatment in sequence. The mechanical treatment includes frosting and sandblasting. The metal plate frame is aluminum-magnesium alloy 6061. The solution concentration of thiocyanuric acid derivatives is 2-6 wt%. The thiocyanuric acid derivatives include sodium-based, amino-based and alkenyl compounds. The solvent in the thiocyanuric acid derivative solution is ethanol, methanol or isopropanol solution. The drying temperature is 50-100 °C and the drying time is 8-15 min.

[0031] In S2, the crosslinking agent is tetraphenyltin or hexacyclooctadecane, the tetraphenyltin is 0.3-0.5 wt% of the mass of the perfluoroether elastomer, and the hexacyclooctadecane is 0.5-1 wt% of the mass of the perfluoroether elastomer.

[0032] In S3, the hot press vulcanization molding conditions are 140-160 ℃×10-20 min. The vulcanization conditions for secondary vulcanization are 180-220 ℃×4-12 hr. The radiation dose for radiation vulcanization is 30-100 kGy.

[0033] In the embodiment of the present application, the surface of the metal plate frame seal is sandblasted and then cleaned and degreased with ethanol and 5% HF solvent respectively, and the adhesive is placed in an oven and dried at 60°C for 10 min. Other processes are common processes in the industry and will not be repeated in the specific embodiments.

[0034] In the embodiment of the present application, hot pressing vulcanization molding is to place the metal plate frame in the mold for hot pressing vulcanization molding, and the conditions are 160 ℃×16 min. Secondary vulcanization is to take out the metal plate frame bonded with the perfluoroether rubber seal, clean the burrs of the seal, place it in an oven for secondary vulcanization, the vulcanization conditions are 200 ℃×4 hr, and then irradiate vulcanization, the radiation dose is 40 kGy, which is a common process in the industry and will not be repeated in the specific embodiments.

[0035] The reagents used in this protocol are as follows: Perfluoroether elastomer, American Solvay PFR95 raw rubber; Fluorinated silicon dioxide and fluorinated titanium dioxide, for details, refer to the preparation processes shown in the specifications of Chinese invention patents CN115340648A and CN115651139A respectively; PFA micro powder, Daikin NEOFLON ACX-31 from Japan; Thiocyanuric acid alkenyl derivatives, thiocyanuric acid amino derivatives, and thiocyanuric acid sodium derivatives are configured according to Merck products, and the specific ratios are shown in the examples; Perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene, prepared by Shanghai Senhuan New Materials Co., Ltd., the specific steps are shown in Example 6 in US Pat. No. 4,138,426A; Tetraphenyltin, Merck; Hexaoxadiazole, Taihechang Chemical Co., Ltd. Example 1

[0036] S1, the metal plate frame is coated with adhesive, dried and then cooled, the adhesive is an ethanol solution of a sodium thiocyanate derivative with a concentration of 4 wt%; S2, 5 wt% of fluorinated silicon dioxide and 0.4 wt% of tetraphenyltin were added to the perfluoroether elastomer during the thin-pass mixing process to obtain a mixed rubber, the vulcanization point monomer used in the perfluoroether elastomer was nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer was 1.5 wt% of the mass of the perfluoroether elastomer; S3, placing the mixed rubber sheet in a metal plate frame, hot-pressing and vulcanizing the metal plate frame with the mixed rubber sheet in a mold, taking out the metal plate frame, cleaning the burrs of the perfluoroether rubber strip, and then performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly. Example 2

[0037] S1, the metal plate frame is coated with adhesive, dried and then cooled, the adhesive is a methanol solution of amino derivative of trithiocyanate, and the concentration is 2 wt%; S2, 5 wt% of fluorinated titanium dioxide and 0.4 wt% of tetraphenyltin were added to the perfluoroether elastomer during the thin-pass mixing process to obtain a mixed rubber, the vulcanization point monomer used in the perfluoroether elastomer was nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer was 2.0 wt% of the mass of the perfluoroether elastomer; S3, placing the mixed rubber sheet in a metal plate frame, hot-pressing and vulcanizing the metal plate frame with the mixed rubber sheet in a mold, taking out the metal plate frame, cleaning the burrs of the perfluoroether rubber strip, and then performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly. Example 3

[0038] S1, the metal plate frame is coated with adhesive, dried and then cooled, the adhesive is an isopropanol solution of trithiocyanate alkenyl derivative, the concentration is 6 wt%; S2, 5 wt% PFA powder and 0.4 wt% tetraphenyltin were added to the perfluoroether elastomer during the thin-pass mixing process to obtain a mixed rubber. The vulcanization point monomer used in the perfluoroether elastomer was nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer was 3.0 wt% of the mass of the perfluoroether elastomer. S3, placing the mixed rubber sheet in a metal plate frame, hot-pressing and vulcanizing the metal plate frame with the mixed rubber sheet in a mold, taking out the metal plate frame, cleaning the burrs of the fluororubber strip, performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly. Example 4

[0039] The difference between this embodiment and embodiment 3 is that the mass of the fluorinated silica powder is 3 wt % of the mass of the perfluoroether elastomer. Example 5

[0040] The difference between this embodiment and embodiment 3 is that the mass of the fluorinated silica powder is 10 wt % of the mass of the perfluoroether elastomer.

[0041] Comparative Example 1 The difference between this comparative example and Example 1 is that no filler is added to S2.

[0042] Comparative Example 2 The difference between this comparative example and Example 1 is that the fluorinated silicon dioxide is replaced by ordinary silicon dioxide powder.

[0043] Comparative Example 3 The difference between this comparative example and Example 1 is that the mass of fluorinated silicon dioxide is 1 wt % of the mass of the perfluoroether elastomer.

[0044] Comparative Example 4 The difference between this comparative example and Example 1 is that the mass of fluorinated silicon dioxide is 13 wt % of the mass of the perfluoroether elastomer.

[0045] In the above-mentioned embodiments and comparative examples, the prepared assembly has a wire groove size of 5.5 mm×336 mm and a glue height of 14.65 mm.

[0046] Test Method The wire trough size of the assembly to be tested is 5.5 mm × 336 mm, and the glue height is 14.65 mm.

[0047] The assembly was treated with a Triton 160 plasma stripper for 300 min at a power of 800 W. The cycle order during plasma treatment was O2 treatment for 50 min, then NF3 treatment for 50 min, then NF3 treatment for 50 min, then O2 / NF3 treatment for 50 min, then NF3 treatment for 50 min, then NF3 treatment for 50 min, and finally NF3 treatment for 50 min. The flow rate of the above treatment process was 50 sccm (standard cubic centimeters per minute), the pressure was 500 mt, and the balance gas was N2.

[0048] Table 1 Bonding conditions of metal plate frame and perfluoroether rubber assembly

[0049] * Unqualified categories include the adhesion of the perfluoroether rubber strip to the mold during demoulding after molding, impurities such as black spots and / or excessive crystal points (more than 5 particles larger than 0.1 mm), glue marks (caused by poor fluidity of the elastomer), local debonding and warping; ** The unqualified categories include local debonding and excessive number of surface particles (more than 5 particles larger than 0.1 mm, Keyence VHX-X1F, Japan).

[0050] By comparing Example 3, Example 4 and Example 5, it can be seen that the dispersion performance is improved as the content of fluorinated silicon dioxide is reduced, and the product qualification rate is higher. However, when the content of fluorinated silicon dioxide is higher, such as 10 wt% (Example 5), the fluorinated silicon dioxide is prone to agglomeration due to the high content, the number of surface particles increases, and the number of corresponding unqualified products is also high.

[0051] By comparing Example 1 with Comparative Example 1, it can be seen that no filler is added to Comparative Example 1, and the number of unqualified products increases after the secondary vulcanization of the sample, and the main problems are degumming and warping.

[0052] By comparing Example 1 and Comparative Example 2, it can be seen that the number of unqualified products after secondary vulcanization and etching of the sample in Example 1 is low, indicating that fluorinated silica has a stronger bonding ability with perfluoroether elastomer than ordinary silica powder, and the number of unqualified products is low.

[0053] By comparing Example 1, Comparative Example 3 and Comparative Example 4, it can be seen that when the amount of silicon dioxide fluoride added is small, the number of unqualified products after the secondary vulcanization of the sample is large and the yield rate is reduced. When the amount of silicon dioxide fluoride added is large, the number of unqualified products after the secondary vulcanization of the sample increases due to the agglomeration of silicon dioxide fluoride, which does not meet the production requirements.

[0054] In Example 3, 5 wt% PFA powder is added, and in Example 4, an appropriate amount of fluorinated silicon dioxide is added. After secondary sulfurization and etching, the defective rate is low and the finished product rate is high.

[0055] In this specification, the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the partial description of the previous embodiments.

[0056] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for preparing a metal plate frame and fluororubber sealing assembly, characterized in that: include S1, coating the metal plate frame with an adhesive, drying it, and then cooling it, wherein the adhesive is a solution of a thiocyanate derivative; S2. A crosslinking agent and a filler are added to the perfluoroether elastomer during the thin-pass mixing process to obtain a mixed rubber, wherein the filler comprises fluorinated silicon dioxide, fluorinated titanium dioxide or PFA powder, and the mass of the filler is 2-10wt% of the mass of the perfluoroether elastomer; the vulcanization point monomer used in the perfluoroether elastomer is nitrile-containing perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene (8-CNVE), and the vulcanization point monomer is 1.5-3wt% of the mass of the perfluoroether elastomer; S3, placing the mixed rubber sheet in a metal plate frame, placing the metal plate frame with the mixed rubber sheet in a mold for hot pressing and vulcanization, taking out the metal plate frame, cleaning the burrs, and then performing secondary vulcanization, and then performing radiation vulcanization to obtain an assembly.

2. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S1, the metal plate is coated after being subjected to mechanical treatment, solvent cleaning and degreasing, and plasma treatment in sequence, wherein the mechanical treatment includes frosting treatment and sandblasting treatment.

3. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: The metal plate frame is made of 6061 aluminum-magnesium alloy.

4. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S1, the concentration of the solution of the thiocyanate derivative is 2-6 wt %.

5. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S1, the thiocyanate derivatives include sodium-based, amino-based and alkenyl-based compounds.

6. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S1, the solvent in the thiocyanuric acid derivative solution is ethanol, methanol or isopropanol.

7. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S1, the drying temperature is 50-100°C, and the drying time is 8-15 min.

8. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S2, the crosslinking agent is tetraphenyltin or hexacyclooctadecane, the tetraphenyltin is 0.3-0.5 wt% of the mass of the perfluoroether elastomer, and the hexacyclooctadecane is 0.5-1 wt% of the mass of the perfluoroether elastomer.

9. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S3, the hot pressing vulcanization molding conditions are 140-160°C×10-20 min.

10. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S3, the vulcanization conditions of the secondary vulcanization are 180-220°C×4-12 hr.

11. The method for preparing the metal plate frame and fluororubber sealing assembly according to claim 1, characterized in that: In S3, the radiation dose of the radiation vulcanization is 30-100 kGy.

12. A metal plate frame and fluororubber sealing assembly, characterized in that: The method is prepared by the method according to any one of claims 1 to 11.

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