TWI287557B - Plastic material - Google Patents

Abstract

In order to provide a plastic material for the manufacturing of components which are subjected to tribological wear, in particular, of retaining rings for holding semiconductor wafers in chemical-mechanical polishing apparatus, retaining rings made therefrom, with which a significantly longer service life of the retaining rings is achievable, and a method for their manufacture, it is proposed that the plastic material contain matrix and particulate TiC embedded therein.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic material suitable for use in a component that is subjected to frictional wear, particularly in the manufacture of a fixing ring for fixing a semiconductor wafer in a chemical mechanical honing device. And the components manufactured thereby, and the method of manufacturing the same. The group of parts subjected to frictional wear made by the plastic material of the present invention has a wide variety. For example, in many of these components, including deflection pulleys, guide parts, and other components that are subject to sliding friction during production and pipe coating. Blades and guide vanes for turbines and generators, as well as rotary parts for compressors and vacuum pumps are also examples. ~ In addition, guide bushings, surface bearings and the like are also typical applications of the plastic materials of the present invention. The piston gasket and guiding parts in the impact body are also very suitable for the components produced by the plastic material of the present invention. A retaining ring of the type described in the first paragraph of the present specification, for example, U.S. Patent No. 6,25,215, and a component of the same use of the plastic material according to the present invention can be used with considerable benefit. The retaining ring is an extreme example of a component that is subject to high frictional losses. Therefore, the present invention is based on the problems associated with the retaining ring and is described in substantial detail. [Prior Art] At present, an integrated circuit is typically formed on a semiconductor substrate, particularly a germanium wafer, by continuous deposition of a conductive layer, a semiconducting layer, and an insulating layer on a wafer. After deposition of the various layers, a 1287557 etch was performed to create a circuit function. After the series of layers are sequentially deposited and etched, the uppermost surface of the semiconductor substrate, that is, the outer surface of the substrate becomes less flat. This uneven surface creates some problems in the photolithographic steps of the integrated circuit process. Therefore, it is necessary to periodically planarize or level the surface of the semiconductor substrate. _ The so-called chemical mechanical polishing (hereinafter referred to as CMP process) is a kind of The method of receiving and receiving. Typically, this method of planarization requires the substrate, i.e., the semiconductor wafer, to be placed on a carrier or honing head. The exposed substrate surface is then placed on a rotating honing pad. A control force is applied to the substrate by the carrier to - press the substrate onto the honing pad. A polishing agent and honing particles containing at least one chemically reactive substance are supplied to the surface of the honing pad. - One of the most important cost factors in the CMP process is the fixed ring which is worn due to the considerable number of times of shutting down the machine. Replacement.

In the case of a full reference to the contents of the present invention, U.S. Patent Nos. 2004-00654 1 2 A and 2004-0 067 723 A have the equivalent of the retaining ring disclosed in U.S. Patent No. 6,251,215. The improvement, in particular, can be replaced relatively easily and quickly. Despite these improvements, there has been considerable cost-effectiveness in reducing the wear on the retaining ring during the CMP process during wafer fabrication. SUMMARY OF THE INVENTION It is an object of the present invention to provide a plastic material for manufacturing a component that is resistant to wear, particularly a retaining ring, thereby allowing the manufactured retaining ring to have a significantly longer service life. . This object can be achieved by a plastic material as defined in the first paragraph of the patent application. Titanium carbide (TiC) is a material with considerable hardness (Vickers hardness 3400). Therefore, when it is used as an additive for plastic materials for sliding and friction applications, as in the case of the CMP process, the problem to be solved is the problem caused by the increased wear, rather than the service life of the plastic material. Shorter question. Surprisingly, titanium carbide can be integrated with the plastic substrate, thus providing the assembly with relatively improved sliding friction characteristics and service life. - The linear thermal coefficient of e x p a n s i ο η of the titanium carbide is 3 1 5 . C is 0. 〇 2 % also has its advantages, it can be selected for plastic substrates for individual use, and can be further processed if necessary without considering carbonized titanium particles. Its low thermal conductivity of about 0.041 cal/sec cm °C also has a positive influence on the plastic material Φ containing titanium carbide particles in the present invention. It is avoided that heat generated in the application of sliding friction is quickly conducted into the surrounding plastic substrate. Surprisingly, with the progressive coating of titanium carbide particles in a plastic substrate, it has been found that the wear of components made from such plastic materials is significantly reduced. In the retaining ring, it is preferred that the groove is made on the surface by the machine's opening toward the honing surface of the C Μ P device and from the inside of the retaining ring to the periphery thereof to ensure that all self-retaining ring wear can be It is discharged along with the polishing agent 1287557. Usually, on the one hand, based on the cost of titanium carbide particles, and on the other hand, based on frictional considerations, the maximum enthalpy of the titanium carbide particle content is limited to 30% by weight. In particular, when the cost of the plastic material as the substrate is higher than the cost of the titanium carbide particles, it is recommended to use a high content, which in addition to reducing the wear and tear, and the effect of lowering the price of the plastic material becomes necessary. In many applications, components manufactured in proportions of 20 • or less are available in a wide range of features. In applications that generate high temperatures, a good result is obtained at a level of 15 to 25 wt%. A more desirable range is from 20 to 25% by weight. • Titanium carbide materials are preferably those that use a fine particle type, that is, a particle size of less than 1 μ μπι. In particular, titanium carbide particles having an average particle diameter of from 1 to 2 μm are preferred, and more preferably from 1.2 to 1.4 μm. - These particle sizes are small enough on the one hand to avoid any interference and on the other hand large enough to significantly improve the wear resistance. The preferred particle form of the titanium carbide particles is in the form of particles, especially spherical particles. Titanium carbide particles with a smooth surface, i.e., a crack-free surface, can be useful for versatile applications. In order to ensure a particularly good coating of the titanium carbide particles in the plastic substrate, it is preferred to treat the titanium carbide particles with a primer before combining them with the plastic material. Preferably, the particles have a primer layer. Incidentally or alternatively, the provided titanium carbide particles may be partially fluorinated. This improves the bonding of the plastic substrate. In particular, polymeric materials which are compatible with titanium carbide on the one hand and which are compatible with the plastic material of the individually selected substrate on the other hand are suitable as primers. Compared to 1287557, the primer layer contains a fluorine-containing polymer. Additionally or alternatively, the primer may be comprised of a group reactive with the plastic material of the substrate to form a covalent bond between the primer and the plastic material of the substrate. The invention is further related to components, particularly fixed rings for semiconductor wafers fabricated using the above-described plastic materials. - Even from a manufacturing point of view, the uniform distribution of the titanium carbide particles in the plastic substrate forms a relatively simple form, but the components of the present invention are not necessary for this requirement. # The titanium carbide particles in the plastic substrate preferably have a higher content in the worn surface area of the adjacent component than in the non-wear area. Incidentally or selectively, the inwardly radiating region of the component may have a lower content (gradually or continuously decreasing) of titanium carbide particles, or more preferably substantially free of titanium carbide particles. . This is further advantageous in that the use of the titanium carbide particles is limited to areas of the assembly that are subject to wear, and thus, as in the case of the fixed ring and the semiconductor wafer, unintended contact with the titanium carbide particles can be virtually eliminated. • In terms of components, especially those belonging to the embodiments described below, for example, it is possible to provide a wear layer made of a tubular semi-finished product by means of an inner wall which does not contain titanium carbide and which is coaxial with It is made by co-extrusion of titanium carbide foreign currency. The different amounts of titanium carbide particles in the wear layer of the assembly can of course be achieved by different manufacturing processes, for example using a sintering process. The invention is further related to a method of manufacturing a component, such as a patent application.范-10- !287557 ^ The person defined in items 17 and 18. In the manufacturing method, it is important that the plastic material filled with titanium carbide is subjected to a specific temperature control after molding. This is to enable the plastic material as the substrate to achieve a predetermined crystallinity'. It is to minimize the tension of the components. - Embodiments The above and further advantages of the present invention will be further illustrated by the following examples and with reference to the drawings. • Friction and wear measurements _ in the so-called Bullerian honing/polishing machine (Model: Buehler Phoenix 4 0 0 Type 49-4 1 0 1 -260 of Buehler Ltd., Lake Bluff, - Illinois, USA), The friction and wear of the plastic material in the U example are determined under the following conditions: 硏: honing agent (honing liquid): Semisperse SS-12 oxidation by Cabot Microelectronics, Research and Technology Center Aurora, Illinois, USA • Oxide slurry. The Rodel CR1C1400-A-3 urethane skateboard manufactured by Rohm & Hass CMP Development Center, Newwark, Delware, USA was used as a honing pad. The Bullerian honing/polishing machine was rotated counter-rotating at 150 rpm and the bearing ring of the retaining ring against the slide was operated at 3.8 psi at 196.25 ft./min. Test sample: -11- 1287557 For the purpose of the test, a plastic ring with an outer diameter of 3 2 0 m m, an inner diameter of 290 m, and a height of 12 m was made of extruded hollow tubes made of various plastic materials. When the plastic material of the present invention is used, the titanium carbide particles in the plastic substrate are uniformly distributed in each case. A fluoropolymer-coated titanium carbide particle marketed by Pacific Particulate Materials Ltd. (Port Coquitiam, - B.C., Canada) is used as a designated titanium carbide particle. These titanium carbide particles have a very narrow particle size from 1.2 to 1.4 μm. • The titanium carbide particles are first synthesized with the plastic material substrate of the retaining ring, and then the compound is formed by pushing into the hollow tube, and the retaining ring is later cut from the hollow tube. Hollow tubes are used to temper to affect crystallinity and reduce the tension exhibited in the material. The heating conditions for PEEK and PPS materials are as follows: Heating at 120 ° C for three hours at 22 ° (^0: heating furnace temperature for four hours at 220 ° C holding time: 11⁄2 hours per cm wall thickness Cooling rate: 20 ° C / hour until the temperature reaches

40 ° C Example 1: In this example, the honing properties of a plastic retaining ring made of standard PPS and PP S containing 22% by weight of titanium carbide particles were tested. The test data is listed in Figure 1. The table on the left of the chart, Table-12- 1287557, shows the plastic retaining ring made of standard PPS, and the fields on the right in the chart indicate the basis. The fixing ring of the titanium carbide granules in the PPs produced by the present invention. The results show that the wear of the retaining ring according to the present invention is significantly lower than that of the standard PPS produced by the one hour test even after the test for 8 hours. Example 2: In this example, the abrasive properties of a plastic retaining ring made of standard PEEK and PEEK containing 22% by weight of titanium carbide particles were tested. The test data is listed in Figure 2, where the various fields to the left of the chart represent plastic retaining rings made of standard PEEK, and the "right fields" to the right of the chart indicate that they are manufactured according to the present invention. The fixing ring of the titanium carbide particles was filled in PEEK. The results show that the fixing ring according to the present invention is significantly more wear-resistant than the standard PEEK tested after 1 hour even after the 8-hour test. The ring is even lower. ® The wear factor here is slightly higher than that measured from the PPS material, but is still several times lower than the wear ring made of the unfilled standard PPS material. The so-called "self-reinforcing polymer" (poly-reinforcing polymer) is a poly-para-benzene, which is used as a plastic material and has a different proportion of titanium carbide particles. The percentage of the fixing ring used in the present invention is 5.5, 11, 22% by weight. The results show that at 5.5 wt% of the titanium carbide particles, the wear has been greatly reduced by 1,287,557. At higher levels, wear initially increased again (11% by weight). However, when the content of titanium carbide particles was further increased (22% by weight), the wear was again reduced. This particular feature is observed from auto-reinforced polymers. Similar relationships can be observed in fiber reinforced plastics, but these examples are not recommended for the fabrication of semiconductor wafer retaining rings. - Embodiment 4: In this embodiment, a comparison is made between the wear and tear of various high performance plastics. The wear data is shown in Figure 3, where the left-to-right field shows the wear of the following plastics:

Standard PPS PET

- PEEK

PEEK PEKK containing 1% by weight of PTFE. Poly(p-diphenyl) The number of PET plastics shown in the graph of Figure 3 is quite good, but by using the titanium carbide of the present invention, it can be further Improve these numbers. PET is a constituent material suitable for use as a retaining ring, but is only suitable for simple semiconductor structures such as memory wafers, while high performance plastic PPS, PEEK and polypara benzene are suitable for use in complex semiconductor structures, such as processing wafers. Finally, Figures 4 and 5 are schematic views of the retaining rings 1 and 3, respectively, of the present invention, each having a wear layer 12 and 32, respectively composed of plastic substrates 14 and 34, wherein It is coated with titanium carbide particles 16 and 36. -14- 1287557 · The retaining ring 1 所示 shown in Fig. 4 (Fig. 4a is an enlarged partial cross-sectional view thereof), the content of the titanium carbide particles adjacent to the surface 18 to be subjected to wear is relatively unnecessary. The area that is subject to wear is 20 high. This particle distribution is recommended for plastics with lower raw material prices than titanium carbide materials. If the material of the high-performance plastic forming the substrate is more expensive than the titanium carbide material, based on the consideration of cost minimization, it is of course possible to use a uniform amount of titanium carbide particles throughout the wear layer without any adverse effects. #图5 shows a fixed ring 3 〇 with a further treatment of the distribution of titanium carbide particles (Fig. 5a is an enlarged partial cross-sectional view thereof) in which titanium carbide particles are 'assigned to the region 38 adjacent to the fixed ring 30 The inner surface 40 is provided to improve the reliability of the wafer 42 disposed in the retaining ring so as not to come into contact with the titanium carbide particles contained in the material to be worn. Figures 4 and 5 respectively show the one-piece retaining ring in the US application No. 2004-0065412 A. It should be understood that the plastic material of the present invention can also be properly applied according to the US 2004- 006773 Patent application No. A. Single-piece retaining ring in the case, and the improvement of its wear characteristics has the same successful effect. [Simplified schematic] Figure 1 is a standard PPS and contains 22% by weight of carbonization. Schematic diagram of the test data for testing the abrasive properties of the plastic retaining ring made of PPS of titanium particles; Figure 2 is the abrasion of the plastic retaining ring made of standard PEEK and PEEK containing 22% by weight of titanium carbide particles. Tests for testing the characteristics 1287557. Schematic diagram of the data; Figure 3 is a schematic diagram of the comparison of the wear 値 for various high-performance plastics; Figure 4 is the US Patent Application No. 2〇〇4·〇〇65412 A Fig. 4a is a cross-sectional view of an enlarged portion of Fig. 4; Fig. 5 is a perspective view of a one-piece retaining ring in the patent application No. 2004-00654 1 2 A ; • Figure 5a is a cross-sectional view of the enlarged portion of Figure 5; [Explanation of the main components] 10 Retaining ring 12 Worn layer 14 Plastic substrate 16 Titanium carbide 丄%! 18 Abrasion-resistant surface 20 Unweared area 30 Fixed Ring 32 Wear layer 34 Plastic substrate 3 6 Titanium carbide particles 3 8 Wear-resistant surface 40 Inner surface 42 Wafer-16-

Claims (1)

One 2 points 0_彳 1287557 螩 No. 94145075 "Plastic materials" patent case X. Patent application scope: 1 · A plastic material for the manufacture of friction and wear components, in particular for the manufacture of fixing rings for fixing semiconductor wafers in honing equipment, the material of which contains plasticity And the titanium carbide particles coated therein, the material is selected from the group consisting of polyetheretherketone, polyphenylene sulfide, polyparaphenylene, ethylene (PTFE) modified polyetheretherketone, and perfluoroalkoxyethylene Fluorovinyl ether copolymer (PFA) modified polytetrafluoroethylene peptone, polyolefin terephthalate, polyimide, polyamidoxime, especially polyphenylene and polyether oxime, And the amount in the plastic material is up to 30% by weight. 2. For the plastic material of claim 1 of the patent scope, wherein the plasticized titanium content is up to 25% by weight 'especially up to 20 weights 3 · as in the plastic material of claim 2, wherein the plasticized titanium content is from 20 to 25% by weight. 4. A plastic material as claimed in claim 1 wherein the carbonization path is from 1 to 2 μm, especially from 1.2 to 1.4 μm. 5 · The plastic expanded material of item 1 of the patent application scope, wherein the surface has a primer layer. 6 · A plastic material as claimed in claim 5, wherein the base polymer, especially a fluorine-containing polymer. 7 · A plastic material as claimed in item 1 of the patent application, in which carbonization is fluorinated. The plastic in the chemical machine and the polytetrafluoroethylene (PFA) and the polyether ketone amine and the carbon in the polycarbotitanium carbide material. The granulated titanium particle layer of the carbon particles in the pigment contains the granules. 1287557 8. The plastic material of claim 1, wherein the titanium carbide particles are in the form of granules, especially spherical particles. 9. A plastic material as claimed in claim 1 wherein the titanium carbide particles have a smooth surface. 10. The plastic material of claim 1 of the patent scope, wherein the self-reinforced plastic, especially the poly-para-benzene, is selected from the plastic material as the substrate, and its content in the titanium carbide particles is 3 to 8 wt%. 1 1 · A component suitable for friction and wear, comprising: A wear layer is made of a plastic material comprising a plastic substrate and titanium carbide particles coated therein; the plastic material is selected from the group consisting of polyetheretherketone, polyphenylene sulfide, and poly-alignment Benzene, polyetheretherketone modified by polytetrafluoroethylene (PTFE), polytetrafluoroethylene, polyether ketone modified by copolymer of perfluoroalkoxyethylene (PFA) and perfluorovinyl ether (PFA) Ketones, polyolefin terephthalates, polyimines, polyamidimines, and poly-[«, especially polyphenylenes and polyethers I; and the content of titanium carbide in the plastic material is 3 0% by weight. 1) 1 12· The assembly of the first aspect of the patent application, wherein the content of titanium carbide particles in the surface area of the adjacent component that is subject to wear is higher than the area that does not need to withstand wear. The assembly of claim 11 or 12, wherein the component is a fixed ring of a semiconductor wafer. 1 4. The assembly of claim 13 wherein the inwardly radiating surface adjacent to the fixed ring The wear layer does not substantially contain titanium carbide particles. 1 5 · A method of assembling the assembly of any one of items 1 to 14 characterized by the following steps: 1287557 a) synthesizing titanium carbide particles with a plastic material selected as a substrate; b) treating synthetic a plastic material to produce sinterable particles; c) sintering the particles obtained in step b) at a predetermined sintering temperature to form a wear layer; d) cooling the sintered material from a sintering temperature in a controlled manner to obtain a predetermined crystallinity And reducing the tension of the wear layer. The method of manufacturing the assembly of any one of claims 1 to 14 is characterized by the following steps: a) selecting titanium carbide particles and being selected Synthesis of a plastic material as a substrate; b) extruding the resultant material to form a wear layer; c) tempering the extruded wear layer to obtain a predetermined degree of crystallinity and reducing the tension of the wear layer.