JPS60177865A - Polisher - Google Patents

Abstract

PURPOSE:To polish the surface of a workpiece by using the polisher having high abrasion resistance, with high efficiency and high accuracy, by using the polisher consisting of the composite constitution prepared by mixing and solidifying high- polymeric materials and hard particles which are not dissolved into polishing liquid. CONSTITUTION:The high-polymeric materials and hard particles which are to be mixed and solidified are properly selected from the materials which can be made uniform through mixing, according to a workpiece, working quality, working efficiency and working precision. Plural kinds of high-polymeric materials and hard particles can be mixed at the same time. Abrasion is generated on the high-polymeric material 6 and hard particles 45 by the working action of polisher, and unevenness is formed on the surface of the polisher by the difference of the abrasion resistance of the both materials, and a stationary state is formed, keeping the above-described step difference constant. The step difference permits the polisher to be held effectively and improves working efficiency. The abrasion resistance and heat resistance of the polisher can be improved by the filling of hard particles, and the service life of the polisher can be prolonged, and the working accuracy of the workpiece can be.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polisher (for example, a polishing band) that can polish a workpiece with high accuracy and efficiency and has high wear resistance.

Polishing is done by using a polisher to rub a polishing agent containing polishing liquid or abrasive agent on the outer surface of the workpiece, and then rubbing it off. This is a processing operation that removes surface irregularities and smoothes them. There are two types of abrasive action on the workpiece: mechanical abrasive action and mechanochemical abrasive action.

The mechanical polishing action is to remove and smooth the protrusions on the surface of a workpiece by the cutting action of fine abrasive particles in the polisher embedded in the polisher surface. This aspect of the polisher requires that the surface be soft enough to embed and retain the abrasive particles, and hard enough to maintain a constant shape as a polisher bulk to retain the overall shape of the workpiece. It is something that we have. On the other hand, mechanochemical polishing action involves rubbing fine abrasive particles suspended in a polishing liquid onto the surface of a workpiece, causing them to adhere through a mechanochemical reaction, and removing the workpiece when the particles are rubbed off. In terms of mechanochemical polishing, the function of a polisher is to rub the polishing liquid or abrasive agent onto the workpiece and scrub it off.

Regarding polishers with unique functions,
Cool pitch, wood pitch, wax: various woods, bamboo;
Woven fabrics, non-woven fabrics, synthetic polymer foam materials: dense molecular materials;
Soft metals and materials such as tin and lead are used.

However, due to their viscoelasticity, tar pitch, wood pitch, and wax easily blend into the surface of the workpiece, and when used in combination with fine abrasive grains for glass polishing, etc., high-precision polished surfaces can be obtained. Because it is a viscous flow under constant stress and its properties are sensitively affected by temperature, strict condition control and skill are required to perform high-precision polishing. Further, even if an attempt is made to increase the efficiency by increasing the sliding speed or processing pressure of the polisher, the precision decreases due to heat generation and viscous flow, so the processing efficiency only reaches about 1 μm/hr per hour.

＠Wood and bamboo are natural products, so they have poor quality of grain stability.
When molded as a polisher, there is non-uniformity and anisotropy of the material, which is disadvantageous in terms of uniformity and isotropy required for high-precision polishing.

θ woven fabrics, non-woven fabrics, and polymeric foam materials tend to be used frequently to compensate for the drawbacks of the polishers mentioned above, and in the case of mechanochemical polishing of semiconductor materials that require particularly high quality, most of these polishers are used. are using.

In this case, the contact between the workpiece and the polisher is good, and it also has the functions of holding, rubbing, and scraping off the polishing agent, but in order to have a soft surface that performs these functions,
The polisher as a whole is also soft and has great compressibility.

For this reason, when grinding under continuous pressure, the machining efficiency gradually decreases due to permanent deformation and wear due to compression, and the service life also decreases by several tens of ON.
It only takes a few hundred hours.

Therefore, when using the polisher in mass production, the time and effort required to replace the polisher and the time required to stop the polishing operation during this time cannot be ignored. Furthermore, since the polisher is soft overall, even if the machining pressure is increased in order to increase the machining efficiency, it will be saturated at 0.6/9/cii at most, resulting in the problem of shortening the life of the polisher. Since the polisher has a structure with pores and voids, it also has the disadvantage that abrasive fine particles in the polishing agent enter and coagulate, causing the polisher to harden.

■In the case of dense polymer materials, there is no part to hold the polishing agent and the material itself is hard, so it is common to use grooves in the surface to supply the polishing agent to the processed surface. Unlike the polisher as a whole, the polisher is hard and the microscopic surface is dense and continuous, so it is necessary to apply high pressure to effectively bring the abrasive particles in the polishing agent into contact with the workpiece surface. Furthermore, even if this contact is achieved, there is no microscopic particle retention structure, so the polisher and workpiece will come into direct contact without the intervention of a polisher agent, due to the short sliding distance between the workpiece and the polisher. Therefore, high machining efficiency cannot be expected.

■Soft gold coffin terisha is mostly used for polishing using diamond abrasive grains. When using this polisher for polishing using general abrasive grains, due to the plastic deformation of the metal, the a grains once embedded in the polisher surface are not easily renewed, resulting in low processing efficiency. A hardened layer will be formed.

Further, when the edges of the workpiece come into strong local contact, the polisher develops plasticity v/n' and bites, creating unevenness on the surface and causing unstable contact.

In addition to this, there is also a polisher with a composite structure in which Teflon powder is mixed into the solder to reduce frictional resistance.

In this case, the polisher is the same as the wax polisher except for the effect of reducing frictional resistance. In addition, materials other than cloth-filled 7-el resin are also used, but this is aimed at retaining the boronizing agent in the cloth-filled part, but phenol resin is a hard and easily abrasive material, and its effect is limited to narrow grooves. There is no big difference from the dense polymer material mentioned above.

In addition, as shown in Patent No. 1,063,256, there is also a polisher that uses a dense polymer mixed with particles that dissolve in a polishing agent (polishing fluid). It is superior to conventional polishers in that it provides a machined surface with a low process-altered layer and has a long polisher life, but in terms of processing efficiency, it utilizes the rubbing and scraping functions of the binder polymer1. ! "do not have.

In view of the above-mentioned circumstances in conventional polishers, the present inventors have developed a method for properly holding polishing agents and polishing the surface of workpieces with high precision.
PolJ Sea that can be polished with high efficiency? After repeated consideration of LC, the polisher is made of M cutting & hardness and strength polymer materials and polymers 1! However, by creating a composite composition that is mixed and solidified with hard fine particles that do not dissolve in the polishing fluid, the polishing agent can remove unevenness caused by the difference in wear between the polymer material and the hard fine particles, depending on the polishing conditions. In addition to being used for holding, various experiments have been conducted with the idea that the increased hardness and strength of the bulk as a whole will enable high-precision, high-efficiency machining of thick shapes, as well as high wear resistance. We were able to complete the present invention.

That is, an object of the present invention is to provide an I-shape for mechanical polishing and/or mechanochemical polishing that can polish the surface of a workpiece with high precision and high efficiency and has high wear resistance.

The structure of the present invention to achieve the above object is to select a workpiece from among materials that can be integrated by combining a polymer material and a hard particle that does not dissolve in the polishing liquid and solidifying the composite material. It may be selected as appropriate depending on the processing quality, processing efficiency, and processing accuracy.

As polymeric materials that can be used, any of thermoplastic materials, thermosetting materials, materials with high or low hardness, and materials with high or low abrasion resistance can be used.

In addition, hard particles include various metal oxides, carbides, nitrides, borides, intermetallic compounds, glass, amorphous metals, single element crystals (St, C, etc.), etc. compared to the base polymer material. It is possible to select one that is hard and does not dissolve in the boiling agent. Of course, it is also possible to mix different types of polymer materials and hard particles at the same time.

Hereinafter, specific contents of the present invention will be explained in detail based on Examples.

Example: A mixture of 10% alumina powder with a particle size of about 10 μm and 90% polytetrafluoride powder was applied to the outer surface of a workpiece (for example, a silicon semiconductor substrate). The product is placed in a mold with a mold and heated to a temperature higher than the molding temperature (the molding temperature of polytetrafluoride) under pressure to solidify it.

After the mixture in the mold solidifies, the mold is cooled to room temperature,
When the solidified material was taken out, a composite structure having a predetermined shape was obtained. The cross-sections of this composite structure are shown in Figures 1 and 2.
As shown in the figure, alumina particles 4 and 5 are contained within the polymer material 6.
was found to be uniformly distributed.

During the polishing process, as shown in FIGS. 1 and 2, the surface of the workpiece 1 is coated with colloidal glue (a glue-like material in which fine silica particles 2 are suspended in a polishing liquid 3 made of water and sodium hydroxide). At the same time, the obtained composite structure is used as a polisher 7 and is reciprocated so as to cross in the lateral direction while applying pressure in the vertical direction to the surfaces of the workpiece 1 and the polisher 7. The polisher 7, which can remove the convex portions on the surface of the workpiece 1 by the action of the polisher present in the workpiece 1 and the polisher 7, is made of a polymeric material (tetrafluoride or tetrafluoride) as described above. ) and hard f! Since it is made of a composite material with Nji particles (alumina particles), the bulk strength of the entire polyshirt is stronger than that of a polymer material alone, and the workpiece 1 under pressure is There is less sinking into the polisher 7 surface, making it possible to perform polishing while maintaining high overall shape accuracy.

■ Due to the processing action of the polisher, the polymeric material 6 and hard particles 4 corresponding to the polishing conditions (However, the hard particles 4 represent only the hard particles on the surface of the polisher 7 among the hard particles in the polisher 7.) Km wear occurs, and due to the difference in wear resistance between the two, the number? Irregularities appear on the surface of the lidar. The level difference between the convex and concave portions of 2' remains constant and reaches a steady state. Figure 1 shows polymer material 6
Figure 2 shows the case where the wear is greater on the hard particles side. The minute irregularities on the surface thus generated become deeper when no pressure is applied to the polisher from the workpiece, and the polishing agent can be effectively retained and processing efficiency can be improved. In particular, in mechanochemical polishing, it is important to effectively cause adhesion between the abrasive particles 2 in the polishing agent and the workpiece 1, and inorganic abrasive particles such as colloidal silica are added to the polishing agent. The suspended aggregation is caused by the presence of hard particles 4 that adhere to the abrasive fine particles through a mechanochemical reaction, which presses the abrasive particles 2 onto the workpiece 1 and causes them to adhere, and the adhesion is scraped off. It is important in promoting the action. If the same material as the hard particles 4 comes into contact with the workpiece not as a particle but as a continuous rigid plate, due to its hardness, the contact pressure distribution will have locally extremely high parts and zero parts. High-pressure areas easily lead to macroscopic destruction and practical polishing is impossible, but because they are dispersed and held in the polymer material in the form of particles, the local high-pressure area can be reduced by the displacement ability of the polymer. Uniform contact pressure can be obtained without the generation of cracks, making it possible to utilize the performance of hard materials that originally have excellent mechanochemical abrasive action.

■ In addition, by appropriately selecting the filling rate of hard particles, this polisher has higher strength and thermal conductivity than is generally known as a filling effect on polymer materials, and also has excellent wear resistance. This can extend its lifespan.

As is clear from the above explanation, the polisher according to the present invention utilizes the excellent properties as a polisher such as mechanochemical reactivity by granulating a hard material that cannot be used as a polisher phase material as a continuous rigid body. It has a high degree of design freedom in that the polymer material and hard particles that are the constituent materials can be selected according to the purpose of the polishing process, and the polisher has a high degree of freedom in design due to the fine irregularities that occur on the polisher surface.
Since it has a drug retention function, its processing efficiency is also very high.

Furthermore, by filling the polisher with hard particles, the wear resistance and heat resistance of the polisher can be improved, and the life of the polisher can be extended and the processing accuracy of the workpiece can be improved. Therefore, if used for polishing optical components such as lenses and prisms that require high precision, or for polishing silicon semiconductor substrates that require high productivity, it will improve precision, efficiency, and wear resistance of the polisher. It is possible to lengthen the time interval between polisher replacements and obtain high productivity.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part showing how a polisher according to an embodiment of the present invention is used, and FIG. 2 is a cross-sectional view of a main part showing a use state of a polisher according to another embodiment of the present invention. In the drawing, 1 is the workpiece, 2 is the number? Polishing fine particles suspended in a polishing agent, 3 a polishing liquid, 4.5 hard particles (alumina particles), 6 a polymer material, 7 Polisher, patent applicant Nippon Telegraph and Telephone Public Corporation and one other representative. Patent attorney Shibu Mitsuishi and 1 other person

Claims (1)

[Claims] A polisher characterized by being made of a composite material made by mixing and solidifying polymer particles and hard particles that do not dissolve in polishing fluid.