CN205765541U - A kind of magneto-rheological fluid dynamic pressure composite polishing device - Google Patents

Abstract

The utility model discloses a magnetorheological fluid dynamic pressure composite polishing device, which comprises a polishing disk, a first rotating shaft, a polishing liquid, a second rotating shaft, a workpiece disk, a magnetic body and a piece to be polished. The upper surface of the polishing disk is along the A plurality of wedge-shaped structures are provided in the circumferential direction, and the wedge-shaped structures include a pin shaft and a wedge block. The pin shaft is fixedly mounted on the upper surface of the polishing disc, and the wedge block is oscillably mounted on the pin shaft. The polishing liquid is covered on the upper surface of the polishing disc and the wedge. When the polishing disc and the workpiece to be polished are in relative motion, the wedges can swing slightly around their respective pins, and the inclination can be automatically adjusted according to the rotation direction and load of the polishing disc, so that the polishing liquid can flow stably from between the workpiece to be polished and the wedge. The fluid dynamic pressure film is formed from the place with a large gap between them to the place with a small gap, so that under the double action of diamond abrasive and hydrodynamic pressure film, the surface material of the polished workpiece can be removed evenly and quickly, and the beneficial effect of rapid polishing and improved polishing effect can be realized. .

Description

A magneto-rheological fluid dynamic pressure composite polishing device

technical field

The utility model relates to a polishing device, in particular to a magneto-rheological fluid dynamic pressure composite polishing device.

Background technique

With the development of electronic information society, semiconductor materials are widely used as high-performance microelectronic components, such as single crystal silicon, aluminum oxide, strontium titanate and single crystal silicon carbide and other electronic ceramic materials are in increasing demand. Generally, the manufacture of semiconductor wafers needs to go through slicing, grinding, polishing and other processes. To achieve good performance, the surface accuracy needs to be ultra-smooth, and the surface accuracy also has high requirements. Taking LED epitaxial sapphire substrates as an example, the general requirements are generally The thickness deviation is less than 10 μm, the overall surface flatness is less than 10 μm, and the surface roughness is less than 0.05 μm. Therefore, the manufacture of semiconductor materials increasingly relies on grinding and polishing technology to meet its production requirements.

At present, there are four main processing methods for semiconductor wafers at home and abroad: 1. The traditional mechanical grinding and polishing processing method in the processing of traditional single crystal Si, Ge and other wafers; 2. The CMP processing method combined with mechanical removal and chemical removal ; 3. Processing by special processing methods such as laser, ultrasonic and other particles; 4. Using magnetorheological processing based on the rheological properties of magnetorheological fluid under a magnetic field. Among them, the existing free abrasive grinding and polishing processing method as a magnetorheological processing method cannot effectively and accurately control the moving speed, trajectory, and residence time of free abrasive particles between the grinding disc and the workpiece during the polishing process. , the free abrasives between the polishing disc and the workpiece and the interface only have larger-sized abrasives for processing, and due to the relative motion, a considerable part of the smaller-sized abrasives have not yet interfered with the surface of the workpiece, that is, they are separated from the interface between the grinding disc and the workpiece , resulting in low processing accuracy and processing efficiency. For example, the cluster magnetorheological polishing method mentioned in patent 200610132495.9 can polish single crystal silicon carbide well and obtain a smooth surface at the nanometer level, but due to the use of an external magnetic field to control the rheology of the magnetorheological working fluid Characteristics, it is difficult to control the distribution uniformity of the small flexible grinding heads formed in the polishing process, so that the thickness deviation, surface flatness and surface quality of the magnetorheologically polished semiconductor substrate are difficult to control.

Utility model content

The purpose of the utility model is to solve the problem of low processing accuracy and efficiency caused by the difficulty in controlling the processing precision existing in the existing free abrasive grinding and polishing processing method, and to provide a magnetorheological fluid flow device with uniform polishing, high processing efficiency and convenient use. Press compound polishing device.

The purpose of this utility model can adopt following technical scheme to reach:

A magneto-rheological fluid dynamic pressure composite polishing device, including a polishing disc, a first rotating shaft, a polishing liquid, a second rotating shaft, a workpiece disc and a piece to be polished, the first rotating shaft and the second rotating shaft are parallel to each other, and the first rotating shaft The two rotating shafts slide horizontally in the direction of the first rotating shaft, the magnetic body is arranged under the polishing disc, the polishing disc is fixedly installed on the first rotating shaft, the workpiece disc and the workpiece to be polished are arranged on the Above the polishing disc, the workpiece disc is fixedly mounted on the second rotating shaft, the workpiece to be polished is fixedly mounted on the lower bottom surface of the workpiece disc, and the lower bottom surface of the workpiece to be polished is connected to the upper surface of the polishing disc contact; the upper surface of the polishing disc is provided with a plurality of wedge-shaped structures along the circumferential direction, and the wedge-shaped structures include pins and wedges, and the pins are fixedly installed on the upper surface of the polishing disc, and the wedges It can be swingably installed on the pin shaft, and the polishing liquid covers the upper surfaces of the polishing disc and the wedge.

Further, a nozzle is provided above the polishing disc, and the polishing solution flows onto the upper surface of the polishing disc through the nozzle.

As a preferred solution, the piece to be polished is a semiconductor wafer.

Further, the end surface magnetic field strength of the magnetic body is not less than 2000Gs.

Further, there are multiple magnetic bodies, and the magnetic poles are arranged in a staggered arrangement.

Further, the piece to be polished is pasted on the lower bottom surface of the workpiece disk.

As a preferred embodiment, the inclination angle between the wedge and the polishing disc is 0-15 degrees.

Implementing the utility model has the following beneficial effects:

1. During the polishing process of the utility model, the working liquid covers the wedge-shaped structure on the upper surface of the polishing disc. When the polishing disc and the workpiece to be polished are in relative motion during the polishing process, the polishing liquid flows from the workpiece to be polished and the wedge. The fluid dynamic pressure film is formed from the place with a large gap to the place with a small gap. Under the double action of diamond abrasive and hydrodynamic pressure film, the surface material of the workpiece to be polished is removed evenly and quickly, which greatly improves the uniformity and efficiency of the polishing process. The purpose of fast polishing and improving the polishing effect.

2. In the polishing process of the utility model, when the polishing disc and the workpiece to be polished are in relative motion, the wedges can swing slightly around their respective pins, and the inclination can be automatically adjusted according to the rotation direction and load of the polishing disc to adapt to the speed of the polishing disc. And load requirements, so that the polishing liquid can stably flow from the place where the gap between the workpiece and the wedge is larger to the place where the gap is smaller to form a hydrodynamic pressure film, so that the dual effects of diamond abrasive and hydrodynamic pressure film The surface material of the polished workpiece can be removed uniformly and quickly, which greatly improves the uniformity and efficiency of the polishing process, and achieves the purpose of rapid polishing and improving the polishing effect.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural view of a magnetorheological fluid dynamic pressure composite polishing device of the present invention;

Fig. 2 is the structural representation of the polishing disk of Fig. 1;

Fig. 3 is a structural diagram of the working state of the workpiece to be polished in the magnetorheological fluid dynamic pressure composite polishing device of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Example

Referring to Fig. 1 and to Fig. 3, the present embodiment relates to a magneto-rheological fluid dynamic pressure composite polishing device, including a polishing disc 1, a first rotating shaft 2, a polishing liquid 3, a second rotating shaft 4, a workpiece disc 5, and a workpiece to be polished 6 and a magnetic body 7, the first rotating shaft 2 and the second rotating shaft 4 are parallel to each other, and the second rotating shaft 4 slides horizontally in the direction of the first rotating shaft 2, and the magnetic body 7 is arranged under the polishing disc 1 , the polishing disc 1 is fixedly mounted on the first rotating shaft 2, the workpiece disc 5 and the workpiece 6 to be polished are arranged above the polishing disc 1, and the workpiece disc 5 is fixedly mounted on the second rotating shaft 4, the workpiece 6 to be polished is fixedly mounted on the lower surface of the workpiece disc 5, and the lower surface of the workpiece 6 to be polished is in contact with the upper surface of the polishing disc 1; the upper surface of the polishing disc 1 is along the A plurality of wedge-shaped structures are provided in the circumferential direction, and the wedge-shaped structures include a pin shaft 81 and a wedge block 82, the pin shaft 81 is fixedly mounted on the upper surface of the polishing disc 1, and the wedge block 82 is swingably mounted on the On the pin 81 , the polishing liquid 3 covers the upper surface of the polishing disc 1 and the wedge 82 . The workpiece 6 to be polished is a semiconductor wafer, such as a sapphire substrate. The preparation method of the polishing liquid 3 is to add 2 to 20% by weight and an average particle size of 1 to 50 μm in an oil-based or water-based carrier liquid. Abrasives, stabilizers such as glycerin or oleic acid with a weight percentage of 1 to 10, antirust agents with a weight percentage of 1 to 10%, and carbonyl iron powder with a weight percentage of 15 to 40% and an average particle size of 1 to 50 μm; the most preferred , the polishing liquid 3 is composed of deionized water, a concentration of 15% and a diamond abrasive with an average particle diameter of 3 μm, a concentration of 30% and an average particle diameter of carbonyl iron powder of 5 μm, a concentration of 10% glycerin and a concentration of 2 % of rust inhibitor composition. During the polishing process, when the polishing disc 1 and the workpiece 6 are in relative motion, the wedge 82 can slightly swing around the pin shaft 81, and automatically adjust the inclination according to the rotation direction and load of the polishing disc 1 to adapt to the speed of the polishing disc 1 and load requirements, so that the polishing liquid 3 can stably flow from the place where the gap between the workpiece 6 to be polished and the wedge 82 is larger to the place where the gap is smaller to form a fluid dynamic pressure film, thereby forming a hydrodynamic pressure film between the diamond abrasive and the hydrodynamic pressure film Under the double action of the machine, the material on the surface of the workpiece to be polished can be removed evenly and quickly, which greatly improves the uniformity and efficiency of the polishing process, and realizes the purpose of fast polishing and improving the polishing effect.

The carbonyl iron powder in the polishing liquid 3 is adsorbed to the upper surface of the polishing disc 1 under the action of the magnetic field force of the magnetic body to form a grinding head structure. During the polishing process, the polishing disc 1 and the workpiece 6 to be polished are in relative motion , the polishing liquid 3 flows from the place where the gap between the workpiece 6 to be polished and the wedge 82 is larger to the place where the gap is smaller to form a hydrodynamic film, and under the double action of the grinding head structure and the hydrodynamic film, it can be removed evenly and quickly. The surface material of the workpiece 6 greatly improves the uniformity and efficiency of the polishing process, and realizes the purpose of fast polishing and improving the polishing effect.

The inclination height of the wedge 82 is no more than 1.5 mm, the inclination angle thereof is 0° to 15°, and the width of the platform 11 is 1.5 to 3 mm. The wedge 82 enables the polishing liquid 3 to be stored on the upper surface of the wedge 82 and the upper surface of the polishing disc 1. During the polishing process, the polishing disc 1 and the workpiece 6 to be polished are in relative motion, and the polishing liquid 3 is removed from the polishing disc 1. The fluid dynamic pressure film is formed by flowing from the place with a larger gap between the piece 6 and the wedge 82 to the place with a smaller gap, so as to improve the uniformity and efficiency of polishing.

The top of the polishing disc 1 is provided with a nozzle 9, and the polishing liquid 3 flows onto the upper surface of the polishing disc 1 through the nozzle 9; the speed at which the polishing liquid 3 is sprayed onto the polishing disc 1 is 70-90 milliliters ensures the supply of polishing liquid 3 to ensure the quality of polishing.

The workpiece 6 to be polished is pasted to the lower bottom surface of the workpiece plate 5, so that the installation and disassembly of the workpiece 6 to be polished can be quickly realized, and the processing efficiency is further improved.

What is disclosed above is only a preferred embodiment of the utility model, and of course it cannot limit the scope of rights of the utility model. Therefore, the equivalent changes made according to the claims of the utility model are still covered by the utility model. scope.

Claims (7)

1. a magneto-rheological fluid dynamic pressure composite polishing device, it is characterised in that: include polishing disk, first turn Axle, polishing fluid, the second rotating shaft, workpiece plate, magnetic and polished part, described first rotating shaft and second turn Axle is parallel to each other, and described second rotating shaft is slided to the first rotor shaft direction level, and described magnetic is located at described The lower section of polishing disk, described polishing disk is fixedly installed in described first rotating shaft, described workpiece plate and polished Part is located at the top of described polishing disk, and described workpiece plate is fixedly installed in described second rotating shaft, described in wait to throw Light part is fixedly installed in the bottom surface of described workpiece plate, and the bottom surface of polished part and described polishing disk is upper Surface contacts；The upper surface of described polishing disk is along the circumferential direction provided with multiple wedge structure, and described wedge shape is tied Structure includes that bearing pin and voussoir, described bearing pin are fixedly installed in the upper surface of described polishing disk, and described voussoir can be put Moving and be installed on described bearing pin, described polishing fluid is covered on the upper surface of described polishing disk and voussoir.

A kind of magneto-rheological fluid dynamic pressure composite polishing device the most according to claim 1, it is characterised in that: Described polishing disk be arranged over jet pipe, described polishing fluid is flowed on the upper surface of described polishing disk by jet pipe.

A kind of magneto-rheological fluid dynamic pressure composite polishing device the most according to claim 1, it is characterised in that: Described polished part is semiconductor wafer.

A kind of magneto-rheological fluid dynamic pressure composite polishing device the most according to claim 1, it is characterised in that: The magnetic fidle of end intensity of described magnetic is not less than 2000Gs.

5. according to a kind of magneto-rheological fluid dynamic pressure composite polishing device described in claim 1 or 4, its feature It is: described magnetic is set to multiple, and the interlaced spread configuration of magnetic pole.

A kind of magneto-rheological fluid dynamic pressure composite polishing device the most according to claim 1, it is characterised in that: Slanted angle between described voussoir and described polishing disk is 0～15 degree.

7. according to the arbitrary described a kind of magneto-rheological fluid dynamic pressure composite polishing device of claims 1 to 3, its It is characterised by: described polished part pastes the bottom surface of described workpiece plate.