A Patterning Automatic Coating and Knife Coating Device for Preparing a Polishing Pad

Abstract

The present invention provides a patterning automatic coating and doctor blade device for preparing a polishing pad, which relates to the technical field of polishing pad equipment. It includes: a stirring device, a feeding device, a supporting device, a magnetic adsorption turntable device, a roller doctor blade device and a waste collection device. The polishing pad abrasive coating device capable of patterning design according to this solution can ensure the patterning, uniformity and flatness of the abrasive layer while ensuring the quantitative and constant-speed dropping of the abrasive coating, thereby improving the production efficiency of the polishing pad, enriching the types of production, and expanding its application fields.

Description

Technical Field

[0001] The present invention relates to the technical field of polishing pad production equipment, and more specifically, to a patternable automatic coating and scraping film device for preparing a polishing pad. Background Art

[0002] Polishing, as a traditional precision machining technology, aims to achieve extremely high flatness, smoothness, and shape accuracy on the surface of workpieces, and is usually applied to fields with extremely high surface requirements for optical elements, semiconductor devices, precision mechanical parts, etc. A fixed abrasive polishing pad is the core of the polishing technology. In this type of polishing pad, the abrasive is firmly bonded to the polishing pad substrate, and the movement trajectory of the abrasive is semi-deterministic. Only the relatively protruding abrasives on the polishing pad can contact the workpiece, thereby achieving precise material removal and improving the polishing efficiency.

[0003] As an important tool for polishing processing, the quality of the fixed abrasive polishing pad directly affects the quality of the polishing effect and plays a key role in the polishing of various materials such as metals, semiconductors, and ceramics. The fixed abrasive polishing pad mainly consists of three parts: an abrasive layer, a rigid layer, and an elastic layer. The addition of the rigid layer is beneficial to improving the surface profile retention ability of the polishing pad, while the elastic layer and the abrasive layer are related to the uniformity of the surface quality of the polished workpiece. Appropriate elasticity can effectively avoid scratching the surface of the workpiece. During the production of the polishing pad, the abrasive and the binder are made into a slurry and then coated on the surface of the substrate. Different pattern designs on the surface of the polishing pad and the coating effect directly affect the subsequent polishing quality.

[0004] For the conventional production of the abrasive layer, generally, abrasives are added to the surface of the substrate, and then the slurry is scraped and coated evenly by manual scraping. The dripping of the slurry on the substrate is mostly achieved manually, and the addition amount is greatly affected by humans. The scraping knife used in the slurry coating process is a metal plate or a resin plate, and there are problems such as unsmooth scraping during the scraping process for some uneven substrates, or uneven thickness of the abrasive layer on the surface after scraping. Moreover, the surface of the polishing pad after scraping is flat and cannot be pattern-designed. The entire coating and scraping process is time-consuming and laborious, with low efficiency. Summary of the Invention

[0005] The present invention discloses a patternable automatic coating and scraping film device for preparing a polishing pad, which has a simple structure and is convenient to operate, aiming to solve the above-mentioned problems.

[0006] The present invention adopts the following solutions:

[0007] A patternable automatic coating and scraping film device for preparing a polishing pad, comprising: a stirring device, a feeding device, a magnetic adsorption turntable device, a roller blade device, and a waste collection device; wherein, the magnetic adsorption turntable device is adapted to place a polishing pad substrate and drive the polishing pad substrate to rotate; the feeding device is arranged above the magnetic adsorption turntable device and is adapted to continuously convey abrasive to the polishing pad substrate; the stirring device is arranged in the feeding device and is adapted to stir the abrasive grains in the feeding device; the roller blade device is arranged above the magnetic adsorption turntable device and comprises a roller blade with a pattern, and the roller blade is adapted to roll press on the rotating polishing pad substrate so that the abrasive is uniformly coated on the polishing pad substrate and a preset pattern is formed; the waste collection device is arranged on the periphery of the magnetic adsorption turntable device to collect the redundant material during the film scraping process.

[0008] Further, it further comprises a support device, and the support device is used for installing the feeding device and the stirring device.

[0009] Further, the roller blade device comprises a roller blade, the roller blade is set to be cylindrical, its two ends are respectively fixed on the outer edge of the magnetic adsorption turntable device, and the diameter is 5 mm to 30 mm.

[0010] Further, a patterned concave-convex mechanism is arranged on the outer surface of the roller blade, and the patterning includes one or several of linear, polyline, square grid, circular, and dot matrix.

[0011] Further, the polishing pad substrate is adapted to be connected to a stainless steel plate, and an intermediate layer is arranged between the stainless steel plate and the polishing pad substrate.

[0012] Further, the intermediate layer is a fiber material, or non-woven fabric, or polyurethane.

[0013] Further, the abrasive is diamond slurry, or alumina slurry, or silicon carbide slurry, or cerium oxide slurry, the liquid part of the slurry is a viscous resin, or flour, or starch, or chitosan, or sodium alginate liquid, and the concentration of the abrasive is adjustable, being 0.01 wt% to 90 wt%.

[0014] Further, the height of the roller blade from the magnetic adsorption turntable is adapted to be adjustable between 2 mm and 20 mm.

[0015] Further, a peristaltic pump is arranged at the feeding port of the feeding device, and the peristaltic pump is adapted to control the opening degree and flow rate of the feeding port.

[0016] Further, the magnetic adsorption turntable device comprises a turntable and a magnetic chuck arranged on the turntable, a heating device is arranged on the lower surface of the magnetic chuck, and a cooling circulation system is arranged at the bottom of the heating device.

[0017] Beneficial effects:

[0018] In this solution, the polishing pad substrate is placed on the magnetic adsorption turntable device in a magnetic adsorption manner, with a simple fixing method and convenient disassembly. The length of the roller scraper is adjustable and can be adjusted according to the size of the polishing pad. The liquid containing abrasives is added to the feeding device and continuously stirred by the stirring device. The slurry is added to the polishing pad substrate through the feeding device. After the abrasives drip onto the polishing pad substrate, the turntable on the magnetic adsorption turntable device will pass by the roller scraper during rotation. Through the leveling and extrusion of the roller scraper, a polishing pad with a uniformly coated surface thickness is finally obtained. After the polishing point substrate is evenly spread, the feeding device is closed, and the excess slurry is collected by the waste collection device of the turntable during the film scraping process. The automatic feeding device adopted can ensure the uniformity of the abrasives and the quantification of the dropped abrasives by using the automatic stirring and feeding device. By the method of spin coating and film scraping simultaneously, the coating efficiency and uniformity of the abrasives can be improved. At the same time, the scraper used is a metal roller scraper with concave and convex patterns on the surface, which has a certain weight itself. During the coating and film scraping process, its own weight can ensure that the slurry infiltrates well into the substrate, maintaining the flatness of the polishing pad and the uniformity of the abrasives. At the same time, patterning design can be carried out when the roller scraper scrapes the film, which plays a key role in improving the production efficiency and patterning design of the polishing pad. Description of the drawings

[0019] Figure 1 is a schematic structural diagram of a patternable automatic coating and film scraping device for preparing a polishing pad according to an embodiment of the present invention;

[0020] Figure 2 is a schematic structural diagram of the magnetic adsorption turntable device and the waste collection device of a patternable automatic coating and film scraping device for preparing a polishing pad according to an embodiment of the present invention;

[0021] Figure 3 is a schematic structural diagram of the roller scraper device of a patternable automatic coating and film scraping device for preparing a polishing pad according to an embodiment of the present invention;

[0022] Figure 4 is an exploded structural diagram of the feeding device and the stirring device of the roller scraper device of a patternable automatic coating and film scraping device for preparing a polishing pad according to an embodiment of the present invention;

[0023] Figure 5 is a schematic structural diagram of the magnetic adsorption turntable device of a patternable automatic coating and film scraping device for preparing a polishing pad according to an embodiment of the present invention;

[0024] Reference numerals: Stirring device 1, supporting device 2, feeding device 3, peristaltic pump 4, magnetic suction turntable device 5, heating device 51, cooling circulation system 52, magnetic chuck 53, turntable 54, roller scraper device 6, roller scraper 61, mounting bracket 62, connecting rod 63, waste collection device 7. Detailed implementation manners

[0025] Embodiment 1

[0026] Combined with Figures 1 to 5 As shown, this embodiment provides a patternable automatic coating and scraping film device for preparing a polishing pad, including: a stirring device 1, a feeding device 3, a magnetic suction turntable device 5, a roller scraper device 6, and a waste collection device 7; wherein, the magnetic suction turntable device 5 is adapted to place the polishing pad substrate and drive the polishing pad substrate to rotate; the feeding device 3 is arranged above the magnetic suction turntable device 5, and is adapted to continuously convey abrasive to the polishing pad substrate; the stirring device 1 is arranged in the feeding device 3, and is adapted to stir the abrasive grains in the feeding device 3; the roller scraper device 6 is arranged above the magnetic suction turntable device 5, and includes a roller scraper 61 with a pattern (not shown), and the roller scraper 61 is adapted to roll on the rotating polishing pad substrate so that the abrasive is evenly coated on the polishing pad substrate and a preset pattern is formed; the waste collection device 7 is arranged on the periphery of the magnetic suction turntable device 5 to collect the excess material during the film scraping process.

[0027] Combined with Figures 1 to 2 As shown, in this embodiment, the magnetic suction turntable device 5 includes a driving motor, a turntable, and a magnetic device arranged on the turntable. The driving motor is adapted to drive the turntable to rotate, and the magnetic device is arranged on the turntable to adsorb the polishing pad substrate with a stainless steel plate. The turntable is connected to the main shaft base, and the rotation speed of the turntable can be adjusted, and the speed is 10 r / min to 100 r / min, and the diameter of the turntable ≤ 300 mm.

[0028] Combined with Figures 1 to 3As shown, the roller squeegee device 6 includes a roller squeegee 61 and a mounting bracket 62. The mounting bracket 62 is arranged on both sides of the turntable. The mounting bracket has a scale display for convenient adjustment of the height of the roller squeegee, and is provided with a connecting rod for connecting the roller squeegee 61. The roller squeegee 61 can be replaced on the connecting rod 63. In this embodiment, the roller squeegee is set to be cylindrical, and the material can be metals such as copper or aluminum. The diameter of the roller is 5 mm to 30 mm. The two ends of the roller squeegee are respectively fixed on the outer edge of the magnetic adsorption turntable device 5, with a diameter of 5 mm to 30 mm. The height of the roller squeegee from the magnetic adsorption turntable is suitable for adjustment between 2 mm and 20 mm, so as to adjust the pressure on the polishing pad substrate as needed. The outer surface of the roller squeegee is provided with a patterned concave-convex mechanism. The pattern includes one or several of linear, broken line, grid, circular, and dot matrix. When the turntable rotates, the roller squeegee scrapes the abrasive above the polishing pad substrate. By spin-coating and scraping the film simultaneously, the coating efficiency and uniformity of the abrasive can be improved. At the same time, the roller squeegee itself has a certain weight, and during the coating and scraping process, the slurry can be well infiltrated into the polishing pad substrate by its own weight, maintaining the flatness of the polishing pad and the uniformity of the abrasive. Moreover, when the roller squeegee scrapes the film, a patterned design can be carried out, which can improve the production efficiency of the polishing pad and facilitate the preparation of the required pattern on the surface of the polishing pad.

[0029] The polishing pad substrate is suitable for being connected to a stainless steel plate, and an intermediate layer is arranged between the stainless steel plate and the polishing pad substrate. Specifically, by arranging the intermediate layer, the polishing pad substrate can be protected, and at the same time, during the scraping process, the connection with the stainless steel plate through the intermediate layer can effectively reduce the damage to the polishing pad substrate during the scraping process. The intermediate layer is various fiber materials (such as fiber cloth) or non-woven fabric or polyurethane, or other soft materials. By connecting the polishing pad substrate to the stainless steel plate, the polishing pad substrate is convenient to be fixed on the magnetic adsorption turntable device 5 and is convenient to disassemble.

[0030] In this embodiment, a support device 2 is further included, and the support device 2 is used to install the feeding device 3 and the stirring device 1.

[0031] Combined Figure 1 and Figure 4As shown, the feeding device 3 includes a conical feeding tank, which is arranged directly above the center of the turntable. A peristaltic pump 4 is provided at the feeding port of the feeding tank, and the peristaltic pump 4 is adapted to control the opening degree of the feeding port and the feeding rate of the slurry. Since the viscosity of the slurry may vary and the speed will be different, a peristaltic pump is used as the control switch here. The peristaltic pump can control the flow rate to achieve constant speed and quantitative feeding. In addition, the peristaltic pump is equipped with a micro stepping motor and is adapted to a silica gel tube or a BPT tube. The hose is the only consumable and is easy to maintain. The inner diameter of the hose is 2 mm to 10 mm, and the flow rate can be controlled between 1 ml / min and 500 ml / min. According to the uniformity of the required abrasive layer or the depth of the pattern, the flow rate can be adjusted to meet the requirements of different patterns and abrasive particle thicknesses. The stirring device 1 is arranged in the feeding tank and is adapted to continuously stir the abrasive particles in the feeding tank to make the abrasive particles more uniform. The stirring device 1 can adopt an existing stirrer, which will not be elaborated here.

[0032] In one embodiment, the supporting device 2 is arranged on an XY-axis motion mechanism (not shown), so that the feeding device 3 and the stirring device 1 can be driven to move above the polishing pad substrate plane. During preparation, first, a larger flow rate is opened for feeding to quickly cover the polishing pad substrate with the abrasive slurry, and then scraping is carried out; then, according to the uniformity of the abrasive layer on the polishing pad substrate or the depth of the pattern, when the depth of a certain area is small, the feeding device can be controlled to move above the corresponding area and feeding can be carried out with a smaller flow rate, and then scraping is carried out again with a roller knife, which can make the pattern film layer of the entire polishing pad more uniform and reduce the waste of abrasives. It should be noted that the uniformity of the abrasive layer on the polishing pad and the depth of the pattern can be judged by experience or by existing vision technology, which will not be elaborated here.

[0033] Combined with Figure 5As shown, in another embodiment, the magnetic suction turntable device includes a magnetic suction plate 53 and a turntable 54. A heating device 51 is provided on the lower surface of the magnetic suction plate 53, and a cooling circulation system 52 is provided at the bottom of the heating device 51. The magnetic suction plate 53 is arranged above the heating device 51, so that the heating device 51 can heat the magnetic suction plate, and the cooling circulation system 52 can quickly cool down the heating device 51 and the magnetic suction plate after stopping heating. The heating device 51 can be a heating sheet or a heating plate, which can provide heat to the polishing pad substrate and the abrasive slurry during the rolling process, prevent the slurry from solidifying, and at the same time can increase the speed of the abrasive slurry infiltrating into the polishing pad substrate. It should be noted that the temperature provided by the heating device 51 is adjustable to prevent damage to the polishing pad substrate. In addition, the heating device 51 can also accelerate evaporation when the abrasive slurry is relatively thin. During operation, first start the heating device 51 to heat the polishing pad substrate and the abrasive to an appropriate temperature. Then, use the roller squeegee to roll 1 to 3 circles to form a preliminary pattern layer. Then, turn off the heating component and turn on the cooling circulation system 52 to cool down the heating device 51 and the magnetic suction plate 53, and also cool down the polishing pad substrate and the abrasive, reduce the fluidity of the abrasive slurry, and promote the rapid hardening of the abrasive slurry on the polishing pad substrate. During this process, reduce the rotation speed of the turntable 54 and roll slowly to maintain the shape of the pattern layer. By setting the heating device 51 and the cooling circulation system 52 to work successively, the processing efficiency of the polishing pad is improved, and the temperature after forming is convenient for the user to take out the polishing pad.

[0034] In this embodiment, the abrasive is diamond slurry, alumina slurry, silicon carbide slurry or other slurries that can be used for polishing processing. The liquid part of the slurry is a viscous resin, flour, starch, chitosan, sodium alginate liquid, and the concentration of the abrasive is adjustable, ranging from 0.01wt% to 90wt%.

[0035] The waste material collection device 7 includes a waste material receiving tray, which is arranged below the turntable and has a diameter larger than that of the turntable, and is used to collect excess abrasive to collect the thrown-out abrasive grains.

[0036] During operation, the polishing pad substrate is magnetically attracted to the turntable, and the height of the roller squeegee is adjusted. The stirring device 1 is installed at the top of the supporting device 2, and the feeding device 3 is fixed above the supporting device 2. The slurry containing abrasive grains is added to the feeding device 3 and continuously stirred by the stirring device 1. The slurry containing abrasive is added to the polishing pad substrate through the feeding device 3. After the abrasive drops onto the polishing pad substrate, during the rotation of the turntable, it is spin-coated by centrifugal force and the slurry is leveled by the roller squeegee. The roller squeegee itself has a certain weight and a concave-convex patterned texture on its surface. Through the extrusion and film scraping of the roller squeegee, a polishing pad with a uniform slurry thickness and a certain pattern on the surface is finally obtained. During the film scraping process, the excess slurry is collected by the waste collection device 7. The present invention can automatically and efficiently coat the abrasive layer on the polishing pad substrate. The obtained polishing pad can be patterned, and has good application prospects in the polishing fields of metals, ceramics, semiconductors, etc. Through this solution, the efficiency can be improved, and at the same time, the amount of abrasive can be controlled to achieve the unified and batch production of polishing pads.

[0037] Example 2

[0038] Add W5 diamond abrasive to the resin to make a diamond abrasive slurry with a concentration of 3 wt%. Add the slurry to the stirring device, turn on the stirrer, and the stirring speed is 50 r / min. Controlled by the switch of the peristaltic pump, the abrasive drops onto the polishing pad substrate from the discharge port with a diameter of 5 mm at a speed of 5 ml / s at regular intervals and in a fixed amount. Adsorb the polishing pad substrate with a diameter of 200 mm on the magnetic chuck, and the magnetic chuck rotates at a speed of 50 r / min. The roller squeegee is located on the upper surface of the turntable. The material of the roller squeegee is copper, and its shape is a cylinder with a diameter of 10 mm and a length of 200 mm. There are linear stripes on the surface of the cylinder. The roller squeegee straddles the upper surface of the polishing disc substrate, and the height from the upper surface of the polishing disc substrate is 3 mm. After rotating for 5 minutes, the abrasive is evenly coated on the polishing disc substrate, and a polishing pad with linear stripes distributed around the circumference on the surface is obtained. The polishing pad prepared in this example can be used for polishing tools of various materials.

[0039] Example 3

[0040] Add W5 diamond abrasive into chitosan to prepare a diamond abrasive slurry with a concentration of 5 wt%. Add the slurry into a stirring device, turn on the stirrer, with a stirring speed of 70 r / min, controlled by a peristaltic pump, so that the slurry drops onto the polishing pad substrate regularly and quantitatively at a speed of 4 ml / s from an outlet with a diameter of 6 mm. Adsorb a polishing pad substrate with a diameter of 100 mm on a magnetic adsorption turntable device, the turntable rotates at a speed of 80 r / min, the roller scraper is located on the upper surface of the polishing disc, the material of the roller scraper is copper, the shape is a cylinder with a diameter of 8 mm and a length of 100 mm, the surface of the cylinder is square stripes, the roller scraper straddles the upper surface of the polishing disc substrate, the height from the upper surface of the polishing disc substrate is 2 mm. After rotating for 3 minutes, the abrasive is evenly coated on the polishing disc substrate, and a polishing pad with a square pattern on the surface is obtained. The polishing pad prepared in this embodiment can be used for polishing tools of various materials.

[0041] It should be understood that the above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the idea of the present invention belong to the protection scope of the present invention.

[0042] The above introduction of the drawings used in the embodiments only shows some embodiments of the present invention and should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

Claims

1. A patternable automatic coating and doctor blade device for preparing a polishing pad, characterized in that, Comprising: A stirring device, a feeding device, a magnetic suction turntable device, a roller squeegee device, and a waste collection device; wherein, The magnetic suction turntable device is adapted to place the polishing pad substrate and drive the polishing pad substrate to rotate; the magnetic suction turntable device includes a driving motor, a turntable, and a magnetic device arranged on the turntable, the driving motor is adapted to drive the turntable to rotate, and the magnetic device is arranged on the turntable for adsorbing the polishing pad substrate with a stainless steel plate; The feeding device is arranged above the magnetic suction turntable device and is adapted to continuously convey abrasive to the polishing pad substrate; during preparation, first start feeding with a larger flow rate to quickly cover the polishing pad substrate with the abrasive slurry, and then perform film scraping; then, according to the uniformity of the abrasive layer on the polishing pad substrate or the depth of the pattern, control the feeding device to move above the corresponding area and feed with a smaller flow rate, and then scrape the film with the roller squeegee again to make the pattern film layer of the whole polishing pad more uniform; The stirring device is arranged in the feeding device and is adapted to stir the abrasive grains in the feeding device; The roller squeegee device is arranged above the magnetic suction turntable device and includes a roller squeegee with a pattern, the roller squeegee is adapted to roll on the rotating polishing pad substrate so that the abrasive is evenly coated on the polishing pad substrate and a preset pattern is formed; the roller squeegee is adapted to improve the coating efficiency and uniformity of the abrasive by spin coating and scraping the film while being driven by the turntable, and at the same time, the roller squeegee uses its own weight to ensure that the slurry can infiltrate well into the polishing pad substrate during the coating and scraping process; The waste collection device is arranged on the periphery of the magnetic suction turntable device to collect the excess abrasive during the film scraping process; The polishing pad substrate is adapted to be connected to a stainless steel plate, and an intermediate layer is arranged between the stainless steel plate and the polishing pad substrate; The roller squeegee device includes a roller squeegee, the roller squeegee is set to be cylindrical, its two ends are respectively fixed on the outer edge of the magnetic suction turntable device, and the diameter is 5 mm to 30 mm; a patterned concave-convex mechanism is arranged on the outer surface of the roller squeegee, and the patterning includes several types such as linear, zigzag, square grid, circular, and dot matrix.

2. The patternable automatic coating and doctor blade device for preparing a polishing pad according to claim 1, wherein It further includes a support device, and the support device is used to install the feeding device and the stirring device.

3. The patternable automatic coating doctor blade device for preparing a polishing pad according to claim 1, wherein The intermediate layer is a fiber material, or non-woven fabric, or polyurethane.

4. The patternable automatic coating and doctor blade device for preparing a polishing pad according to claim 1, wherein The abrasive is diamond slurry, or alumina slurry, or silicon carbide slurry, or cerium oxide slurry, and the liquid part of the slurry is a viscous resin, or flour, or starch, or chitosan, or sodium alginate liquid, and the concentration of the abrasive is adjustable, being 0.01 wt% to 90 wt%.

5. The patternable automatic coating and doctor blade device for preparing a polishing pad according to claim 1, wherein The height of the roller squeegee from the magnetic suction turntable is adapted to be adjustable between 2 mm and 20 mm.

6. The patternable automatic coating and doctor blade device for preparing a polishing pad according to claim 1, wherein A peristaltic pump is arranged at the feeding port of the feeding device, and the peristaltic pump is adapted to control the opening degree and flow rate of the feeding port.

7. The patternable automatic coating and doctor blade device for preparing a polishing pad according to claim 1, wherein The magnetic suction turntable device includes a turntable and a magnetic chuck arranged on the turntable, a heating device is arranged on the lower surface of the magnetic chuck, and a cooling circulation system is arranged at the bottom of the heating device.

Images