Preparation method of ceramic arm with hollow structure

Abstract

The invention relates to a preparation method of a ceramic arm for semiconductor production, in particular to a preparation method of a ceramic arm with a hollow structure, which comprises the following steps: step 1, preparing an organic blank core; step 2, preparing a skeleton blank: pre-burying the organic blank core in a ceramic raw material and forming to obtain the skeleton blank; thirdly, the organic blank core is removed from the framework blank, and a hollow blank is obtained; 4, sintering the hollow blank to obtain a ceramic blank; and fifthly, the ceramic blank is machined, and the ceramic arm is obtained. The prepared ceramic arm is of an integrated structure, the product performance problem caused by a bonding face is solved, meanwhile, the technology is simple, the preparation cost is low, the structural strength is high, and the service life is long.

Description

Technical Field

[0001] The invention relates to a method for preparing a ceramic arm for semiconductor production, in particular to a method for preparing a ceramic arm with a hollow structure. Background Art

[0002] The ceramic arm, also known as the ceramic handling arm, plays a handling role in semiconductor equipment. It is equivalent to the hand of the semiconductor equipment robot, responsible for carrying the silicon wafer to the designated location. Because silicon wafers are extremely susceptible to contamination by other particles, they are generally carried out in a vacuum environment. The materials used to make the robotic arm need to be resistant to high temperatures, wear-resistant, and have high hardness, and ceramic materials can meet these conditions. In order to ensure the safety of wafer handling and avoid risks such as slippage and falling during the handling process, ceramic arms often also have vacuum air ducts and vacuum suction cups. By vacuuming to form negative pressure, the wafer is firmly adsorbed on the arm to ensure the safety of the handling process. To this end, the interior of the ceramic arm needs to have channels.

[0003] Conventional hollow structure ceramic manipulators are prepared by "bonding" technology. The specific process includes: ① forming two single-sided blanks, ② firing, ③ processing internal channels, ④ bonding the two processed single pieces into a whole with inorganic adhesives, ⑤ firing, ⑥ processing and finishing. The whole process is complicated and costly. The existence of the bonding surface will cause the product to crack along the bonding surface. Bonding defects and the processing of single-sided thin sheets will easily lead to a decrease in the overall strength of the material. The complex bonding process and the use of expensive adhesives will increase the cost of the material. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for preparing a ceramic arm with a hollow structure, and the specific technical solution is as follows:

[0005] A method for preparing a hollow ceramic arm comprises the following steps:

[0006] Step 1, preparing an organic core;

[0007] Step 2, preparing a skeleton blank, embedding the organic blank core in the ceramic raw material and forming the skeleton blank;

[0008] Step 3, removing the organic core from the skeleton blank to obtain a hollow blank;

[0009] Step 4, sintering the hollow blank to obtain a ceramic blank;

[0010] Step five, processing the ceramic blank to obtain a ceramic arm.

[0011] Preferably, the method for preparing the organic core comprises the following steps:

[0012] Configure the core raw materials;

[0013] Mixing raw materials;

[0014] Casting molding;

[0015] The core raw materials include the following in parts by mass:

[0016] 1-5 parts of low density polyethylene;

[0017] 1-5 parts of dioctyl phthalate;

[0018] 50-80 parts of No. 56 fully refined paraffin;

[0019] Beeswax 10-40 parts;

[0020] Graphite 10-30 parts.

[0021] Furthermore, during the mixing, the mixing temperature is 100-150° C. and the mixing time is 2-5 hours.

[0022] Further, the removal of the organic core comprises the following steps:

[0023] A through hole communicating with the organic blank core is provided on the skeleton blank;

[0024] The skeleton blank is heated to cause the organic blank core to melt and flow out from the through hole.

[0025] Wherein, when heating the skeleton blank, heating is performed according to the following steps:

[0026] When heated from room temperature to 80°C, the heating rate is 2-5°C / h;

[0027] When heating from 80℃ to 120℃, the heating rate is 5-20℃ / h;

[0028] The insulation temperature is 120°C and the insulation time is 2-3 hours.

[0029] Furthermore, when the skeleton blank is heated, the skeleton blank is first placed on a recycling container with the through hole facing the recycling container.

[0030] Preferably, the preparation of the skeleton blank comprises the following steps:

[0031] Fabric and scrape it flat;

[0032] Place the organic core according to the position of the blank drawing;

[0033] Fabric and scrape it flat;

[0034] Pressurized molding.

[0035] Furthermore, the pressure of the pressurized molding is 30-100 MPa, and the holding time is 30-60 s.

[0036] Furthermore, the cloth is one of aluminum oxide granules or silicon carbide granules.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The ceramic arm prepared by the method for preparing a hollow structure ceramic arm provided by the present invention is an integrated structure, which solves the product performance problem caused by the bonding surface. At the same time, the process is simple, the preparation cost is low, the structure strength is high, and the service life is long. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a schematic structural diagram of the organic core of the first embodiment;

[0040] Figure 2 It is a schematic diagram of placing the organic core according to the position of the blank drawing in the first embodiment;

[0041] Figure 3 This is a schematic diagram of the first embodiment after the skeleton blank is freed of the organic blank core;

[0042] Figure 4 It is a real photo of Example 1;

[0043] Figure 5 It is the real object photo of embodiment 2. DETAILED DESCRIPTION

[0044] The present invention will be further described with reference to the accompanying drawings.

[0045] A method for preparing a hollow ceramic arm comprises the following steps:

[0046] Step 1, preparing an organic core;

[0047] The method for preparing the organic core comprises the following steps:

[0048] Configure the core raw materials;

[0049] Mix the raw materials at a temperature of 100-150°C for 2-5 hours;

[0050] Casting molding;

[0051] The core raw materials include the following in parts by mass:

[0052] 1-5 parts of low-density polyethylene; 1-5 parts of dioctyl phthalate; 50-80 parts of No. 56 fully refined paraffin; 10-40 parts of beeswax; 10-30 parts of graphite;

[0053] Step 2, preparing a skeleton blank, embedding the organic blank core in the ceramic raw material and forming the skeleton blank;

[0054] The preparation of the skeleton blank includes the following steps:

[0055] The material is spread and scraped flat, and the material is one of alumina granules or silicon carbide granules;

[0056] Place the organic core according to the position of the blank drawing;

[0057] Fabric and scrape it flat;

[0058] Pressurized molding, the pressure is 30-100MPa, and the holding time is 30-60s.

[0059] Step 3, removing the organic core from the skeleton blank to obtain a hollow blank;

[0060] The removal of the organic core comprises the following steps:

[0061] A through hole communicating with the organic blank core is arranged on the skeleton blank;

[0062] Placing the skeleton blank on a recycling container with the through hole facing the recycling container;

[0063] The skeleton blank is heated to cause the organic blank core to melt and flow from the through hole into a recovery container.

[0064] When heating the skeleton blank, the following steps are followed:

[0065] When heated from room temperature to 80°C, the heating rate is 2-5°C / h;

[0066] When heating from 80℃ to 120℃, the heating rate is 5-20℃ / h;

[0067] The insulation temperature is 120°C and the insulation time is 2-3 hours.

[0068] Step 4, sintering the hollow blank to obtain a ceramic blank;

[0069] Step five, processing the ceramic blank to obtain a ceramic arm.

[0070] Embodiment 1

[0071] like Figures 1 to 4 As shown, a preparation of a 99 alumina ceramic arm comprises the following steps:

[0072] The organic core is prepared with the following raw material formula:

[0073] 1 part of low-density polyethylene, 1 part of dioctyl phthalate, 48 parts of No. 56 fully refined paraffin, 40 parts of beeswax, and 10 parts of graphite.

[0074] The raw materials were weighed according to the above formula, mixed in a mixer at 150° C. for 2 hours, and cast into the shape of the internal channel of the ceramic arm using a mold to obtain an organic core.

[0075] In the process of forming the skeleton blank, 99 alumina granules are first laid and scraped flat, and then the organic blank core is placed according to the position of the blank drawing. Then the materials are laid and scraped flat, and pressurized with a hydraulic press. The molding pressure is 50MPa and the pressure is maintained for 50s.

[0076] To remove the organic core, open a hole at the corresponding position of the skeleton blank, place the skeleton blank on the recovery container (with the hole facing downward), and heat it according to the following heating curve:

[0077] Room temperature → 80℃, heating rate 2℃ / h;

[0078] 80℃→120℃, heating rate 5℃ / h;

[0079] Keep the temperature at 120℃ for 2 hours, and after the organic core is basically removed, a ceramic blank with a hollow structure is formed.

[0080] The ceramic blank is then placed into a kiln and fired at 1650°C for 5 hours to produce a 99 alumina ceramic arm blank with a hollow structure.

[0081] like Figure 4 As shown, the ceramic arm blank is processed according to the hole position and related dimensions, surface finish, etc. to prepare a qualified 99 alumina ceramic arm.

[0082] Embodiment 2

[0083] A preparation method of a silicon carbide ceramic arm comprises the following steps:

[0084] The organic core is prepared with the following raw material formula:

[0085] 5 parts of low-density polyethylene, 5 parts of dioctyl phthalate, 60 parts of No. 56 fully refined paraffin, 10 parts of beeswax, and 20 parts of graphite.

[0086] The raw materials were weighed according to the above formula, mixed in a mixer at 100° C. for 5 hours, and cast into the shape of the internal channel of the ceramic arm using a mold to obtain an organic core.

[0087] In the process of forming the skeleton blank, silicon carbide granules are first laid out and scraped flat, and then the organic blank core is placed according to the position of the blank drawing. The material is then laid out and scraped flat, and pressurized with a hydraulic press. The molding pressure is 100MPa and the pressure is maintained for 30s.

[0088] To remove the organic core, open a hole at the corresponding position of the skeleton blank, place the skeleton blank on the recovery container (with the hole facing downward), and heat it according to the following heating curve:

[0089] Room temperature → 80℃, heating rate 5℃ / h;

[0090] 80℃→120℃, heating rate 20℃ / h;

[0091] Keep the temperature at 120℃ for 3 hours, and after the organic core is basically removed, a ceramic blank with a hollow structure is formed.

[0092] The ceramic blank is then placed in a vacuum kiln and fired at 2020°C for 3 hours to produce a silicon carbide ceramic arm blank with a hollow structure.

[0093] like Figure 5 As shown, the ceramic arm blank is processed according to the channel position and related dimensions, surface finish, etc. to prepare a qualified silicon carbide ceramic arm.

[0094] Embodiment 3

[0095] A preparation method of a 95% alumina ceramic arm comprises the following steps:

[0096] The organic core is prepared with the following raw material formula:

[0097] 2 parts of low-density polyethylene, 3 parts of dioctyl phthalate, 55 parts of No. 56 fully refined paraffin, 25 parts of beeswax, and 15 parts of graphite.

[0098] The raw materials were weighed according to the above formula, mixed in a mixer at 130° C. for 3 hours, and cast into the shape of the internal channel of the ceramic arm using a mold to obtain an organic core.

[0099] In the process of forming the skeleton blank, 95 alumina granules are first laid and scraped flat, and then the organic blank core is placed according to the position of the blank drawing. Then the materials are laid and scraped flat, and pressurized with a hydraulic press. The molding pressure is 30MPa and the pressure is maintained for 60s.

[0100] To remove the organic core, open a hole at the corresponding position of the skeleton blank, place the skeleton blank on the recovery container (with the hole facing downward), and heat it according to the following heating curve:

[0101] Room temperature → 80℃, heating rate 3℃ / h;

[0102] 80℃→120℃, heating rate 10℃ / h;

[0103] Keep the temperature at 120℃ for 3 hours, and after the organic core is basically removed, a ceramic blank with a hollow structure is formed.

[0104] The ceramic blank is then placed into a vacuum kiln and fired at 1550°C for 3 hours to produce a 95 alumina ceramic arm blank with a hollow structure.

[0105] The ceramic arm blank is processed according to the hole position, related dimensions, surface finish, etc. to prepare a qualified 95 alumina ceramic arm.

[0106] The ceramic arm is prepared by the "organic core method" and is an integrated hollow structure with no bonding surface. It is mainly used for the handling of semiconductor wafers and silicon chips. The preparation of the ceramic arm includes the preparation, pre-embedding, and removal and recycling of the organic core. The ceramic arm is pressed and sintered to prepare an integrated cavity structure. The preparation process is simple, the cost is low, and the product performance problem caused by the bonding surface is solved.

[0107] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a hollow structured ceramic arm, characterized in that: The following steps are involved: Step 1, preparing an organic core; Step 2, preparing a skeleton blank, embedding the organic blank core in the ceramic raw material and forming the skeleton blank; Step 3, removing the organic core from the skeleton blank to obtain a hollow blank; Step 4, sintering the hollow blank to obtain a ceramic blank; Step five, processing the ceramic blank to obtain a ceramic arm.

2. The method for preparing a hollow structure ceramic arm according to claim 1, characterized in that: The method for preparing the organic core comprises the following steps: Configure the core raw materials; Mixing raw materials; Casting molding; The core raw materials include the following in parts by mass: 1-5 parts of low density polyethylene; 1-5 parts of dioctyl phthalate; 50-80 parts of No. 56 fully refined paraffin; Beeswax 10-40 parts; Graphite 10-30 parts.

3. The method for preparing a hollow structure ceramic arm according to claim 2, characterized in that: During the mixing, the mixing temperature is 100-150° C. and the mixing time is 2-5 hours.

4. The method for preparing a hollow structure ceramic arm according to claim 2, characterized in that: The removal of the organic core comprises the following steps: A through hole communicating with the organic blank core is provided on the skeleton blank; The skeleton blank is heated to cause the organic blank core to melt and flow out from the through hole.

5. The method for preparing a hollow structure ceramic arm according to claim 4, characterized in that: When heating the skeleton blank, heating is performed according to the following steps: When heated from room temperature to 80°C, the heating rate is 2-5°C / h; When heating from 80℃ to 120℃, the heating rate is 5-20℃ / h; The insulation temperature is 120°C and the insulation time is 2-3 hours.

6. The method for preparing a hollow structure ceramic arm according to claim 4, characterized in that: When heating the skeleton blank, the skeleton blank is first placed on a recycling container with the through hole facing the recycling container.

7. The method for preparing a hollow structure ceramic arm according to claim 1, characterized in that: The preparation of the skeleton blank comprises the following steps: Fabric and scrape it flat; Place the organic core according to the position of the blank drawing; Fabric and scrape it flat; Pressurized molding.

8. The method for preparing a hollow structure ceramic arm according to claim 7, characterized in that: The pressure of the pressurized molding is 30-100 MPa, and the holding time is 30-60 s.

9. The method for preparing a hollow structure ceramic arm according to claim 7, characterized in that: The cloth material is one of aluminum oxide granules or silicon carbide granules.

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