TW202330171A - Pin ring for double-sided polishing equipment and double-sided polishing machine - Google Patents

Abstract

The embodiment of the invention discloses a pin ring for double-sided polishing equipment and a double-sided polishing machine, and the pin ring comprises a plurality of pin shafts which are uniformly fixed on a lower polishing unit of the double-sided polishing equipment along the circumferential direction; the plurality of sleeves are arranged on each pin shaft in the plurality of pin shafts in a rotatable manner; the gasket is arranged between the sleeve and the lower polishing unit, the gasket comprises a plurality of through holes allowing each pin shaft to penetrate through, the through holes are configured to allow one pin shaft to penetrate through, the gasket is configured to be in a circular ring shape composed of at least one fan-shaped section, and the fan-shaped sections are arranged in the through holes. And the fan-shaped section comprises at least two through holes.

Description

A pin ring for double-sided polishing equipment and a double-sided polishing machine

The invention belongs to the technical field of semiconductor manufacturing, in particular to a pin ring used for double-sided polishing equipment and a double-sided polishing machine.

In recent years, with the development of the semiconductor industry, higher requirements have been placed on the flatness of silicon wafers. In addition to the global back surface-referenced ideal plane/range (Global Backsurface-referenced Ideal plane/Range, GBIR ), Site Frontsurface referenced least Squares/Range (SFQR), Site Backsurface-referenced Ideal plane/Range (SBIR), etc., also started to use the following new Indicators: Roll Off Amount (ROA) for evaluating the flatness of silicon wafers, also known as Edge Roll Off Amount (Edge Roll Off Amount), Edge Site Frontsurface referenced least squares/range (Edge Site Frontsurface referenced least Squares/ Range, ESFQR); Z-Height Double Differentiation (ZDD) to evaluate curvature changes.

The double-sided polishing process is one of the most effective ways to obtain local planarization and global planarization of silicon wafers. When using double-sided grinding and polishing equipment, the pin ring installed in the double-sided grinding and polishing equipment is used to position and carry the silicon wafer to be ground. carrier plate. When assembling the double-sided grinding and polishing equipment, due to the scattered and large number of pin ring parts, it takes a long time to assemble and unload, and after assembly, it is necessary to manually check whether there is any omission. The regular maintenance of the double-sided grinding and polishing equipment requires high pressure. Washing, the parts on the pin ring are easily washed out by the high-pressure water gun due to dispersion, resulting in debris or metal contamination in subsequent processing.

In order to solve the above technical problems, the embodiment of the present invention expects to provide a pin ring and a double-side polishing machine for double-side polishing equipment, so as to reduce the maintenance cost of the double-side polishing equipment and ensure the quality of subsequent processing.

Technical scheme of the present invention is realized like this: In a first aspect, the present invention provides a pin ring for double-sided polishing equipment, the pin ring includes: a plurality of pin shafts, and the multiple pin shafts are uniformly fixed on the lower polishing unit of the double-sided polishing equipment along the circumferential direction on; a plurality of sleeves, the sleeve is rotatably mounted on each of the plurality of pin shafts; a gasket arranged between the sleeve and the lower polishing unit, the gasket includes for the a plurality of through holes through which each of the plurality of pins passes, the through holes configured to pass through one of the plurality of pins, wherein the gasket is configured to be formed by at least one sector An annular shape composed of segments, the sector segment includes at least two through holes.

In the second aspect, the present invention also provides a double-sided polishing machine, which includes: an upper polishing unit; a lower polishing unit; a silicon wafer carrier plate arranged between the polishing units; a pin ring, the pin ring is installed on On the lower polishing unit, the pin ring is used to limit the carrier disc and drive the carrier disc to rotate between the polishing units, wherein the number of the pin rings is two, namely the first pin ring and the second pin ring , the second pin ring is arranged radially outward around the first pin ring.

An embodiment of the present invention provides a pin ring for double-sided polishing equipment and a double-sided polishing machine. The scattered nature of the pin ring is eliminated by a washer composed of at least one sector section. The through hole, the gasket is assembled on the pin shaft in the way that the pin shaft passes through the through hole, which reduces the number of parts of the pin ring as a whole, saves the disassembly and assembly time of the equipment, and at the same time avoids washing the gasket when using a high-pressure water gun. The phenomenon of dropping and losing, thereby preventing the occurrence of chips caused by processing silicon wafers without gaskets.

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention.

Referring to accompanying drawing 1, in existing double-sided polishing equipment, this double-sided polishing equipment comprises upper polishing unit P and lower polishing unit S, and this upper polishing unit P is used for polishing the upper surface of silicon chip, and lower polishing unit S is used for Polish the lower surface of the silicon wafer. In the actual polishing process, referring to accompanying drawings 1 and 2, the lower polishing unit S is provided with a pin ring 1 to position the silicon wafer carrier C and guide the silicon wafer carrier C between the upper polishing unit P and the lower polishing unit S Rotate between. Referring to accompanying drawings 2 and 3 , the pin ring 1 is composed of a plurality of subunits A arranged in a ring shape, and each subunit A includes a pin shaft 101 , a sleeve 102 and a gasket 103 . The double-sided polishing equipment also includes a driving device, which is used to drive the rotation of the pin ring 1 to drive the rotation of the silicon wafer carrier plate C, so that the double-sided polishing equipment performs material removal processing on the silicon wafer, such as honing, grinding, polishing or grinding .

Referring to accompanying drawing 2 and accompanying drawing 3, common spacer 103 and sleeve 102 are set on pin shaft 101, and spacer 103 is arranged between sleeve 102 and lower polishing unit S, wherein, pin ring 1 is made up of a plurality of sub-units A structure, a single subunit A is provided with an independent gasket 103, each gasket 103 needs to be installed one by one in the assembly stage, and the staff need to spend a lot of time and energy to confirm whether the assembly of the gasket 103 is correct. During regular maintenance of the equipment, the lower polishing unit needs to be rinsed with a high-pressure water gun to remove crystals and/or debris on the lower polishing unit S. During the flushing process, the sleeve 102 needs to be disassembled for cleaning. The individual pads in the single subunit A The sheet 103 is easy to be washed away and lost, resulting in metal contamination in the subsequent processing due to the lack of a gasket 103 at the bottom of the sleeve 102, and because the gasket 103 at the bottom of some sleeves 102 is lost, the height of all the sleeves 102 is not uniform, silicon The non-uniform force on the wafer carrier plate C affects the polishing quality, and even leads to the occurrence of silicon wafer fragments.

In order to solve the above technical problems, referring to accompanying drawings 4 and 5, an embodiment of the present invention provides a pin ring 2 for double-sided polishing equipment, the pin ring 2 comprising: A plurality of pin shafts 201, the plurality of pin shafts 201 are evenly fixed on the lower polishing unit S of the double-sided polishing device along the circumferential direction; a plurality of sleeves 202, the sleeve 202 is rotatably mounted on each pin shaft 201 in the plurality of pin shafts 201; A gasket 203 disposed between the sleeve 202 and the lower polishing unit S, the gasket 203 includes a plurality of through holes 2031 for each of the plurality of pin shafts 201 to pass through, and the through holes 2031 pass through It is configured to allow one of the plurality of pin shafts 201 to pass through, wherein the washer 203 is configured as an annular shape composed of at least one sector section, and the sector section includes at least two through holes 2031 .

In the present invention, the washer 203 is a single washer 203 composed of at least one section, and here, the single washer 203 refers to the fact that the washer 203 is formed as an independent entity by mechanical combination of at least one sector section , the above-mentioned single gasket 203 can simplify the installation steps, save assembly time, and also reduce the risk of fragments caused by missing gaskets during equipment maintenance.

Wherein, the plurality of pin shafts 201 are uniformly arranged in the circumferential direction on the lower polishing unit S, referring to FIG. The way is fixedly installed on the lower polishing unit S. Since the silicon wafer carrier C rotates against the pin ring 2 through direct contact, the pin shaft 201 is made of hardened metal to better support the silicon wafer carrier C, wherein the hard material can be carbonitride or Alloys such as stainless steel, tungsten carbide, etc.

Referring to accompanying drawing 4, this pin ring 2 also comprises a plurality of sleeves 202, and this sleeve 202 is arranged on each pin shaft 201 in a rotatable manner, that is to say, the number of this sleeve 202 is the same as that of this pin shaft 201 equal in number. Specifically, the sleeve 202 has a cylindrical shape as a whole, and the sleeve 202 has a concave hole 2021 opened on one side. The inside of the concave hole 2021 is smooth so that when the sleeve 202 is assembled on the pin shaft 201, the sleeve 202 can rotate around its own central axis with the pin shaft 201 as the rotation axis. The inner diameter of the concave hole 2021 is configured to be greater than or equal to the diameter of the pin shaft 201 , so that the pin shaft 201 can extend into the concave hole 2021 and contact the bottom of the concave hole 2021 along the opening direction. Preferably, the diameter of the pin shaft 201 decreases gradually along the vertical direction to make the assembly of the sleeve 202 easier and improve the assembly efficiency of the equipment. The sleeve 202 is in direct contact with the silicon wafer carrier C. Preferably, the outside of the sleeve 202 engages with the silicon wafer carrier C in a toothed manner. When the sleeve 202 is assembled on the pin shaft 201, there is no friction between the pin shaft 201 and the silicon wafer carrier C, and direct contact occurs between the sleeve 202 and the silicon wafer carrier C, The sleeve 202 is mostly carried on the pin shaft 201 along the length direction, thereby reducing the occurrence of wear of the pin shaft 201. When a certain degree of wear occurs, the sleeve 202 can be directly replaced to improve the maintenance efficiency of the equipment. Wherein, the sleeve 202 is directly in contact with the silicon wafer carrier C, and guides the silicon wafer carrier C to rotate. Also in order to better support the silicon wafer carrier C, the sleeve 202 is made of the above-mentioned hard material. Cartridge 202.

Referring to accompanying drawings 4 and 5, the pin ring 2 further includes a washer 203, which is arranged between the sleeve 202 and the lower polishing unit S to protect the contact surface of the sleeve 202 and the lower polishing unit S . In addition, the washer 203 can also bridge the internal gap of the pin ring 2 , thereby preventing the polishing or cleaning polishing liquid from flowing undesirably into the interior of the device. The washer 203 includes a plurality of through holes 2031, and the through holes 2031 are configured to allow the plurality of pin shafts 201 to pass through. Preferably, the washer 203 is configured to allow one of the plurality of pin shafts 201 to pass through. That is, the number of the through holes 2031 is equal to the number of the pins 201, so that there is a gasket 203 at the bottom of each sleeve 202 to isolate the sleeve 202 and the lower polishing unit S. The through hole 2031 is configured such that its inner diameter is equal to or slightly larger than the maximum diameter of the pin shaft 201 to ensure that the pin shaft 201 can pass through the through hole 2031 . Wherein, the gasket 203 is made of rubber, and the available materials are usually styrene-butadiene rubber, hydrogenated rubber, EPDM rubber, silicon rubber, fluorine rubber, neoprene, perfluororubber, etc., so as to ensure the tension of the gasket 203. Elongation and abrasion resistance. Referring to FIG. 5 , it is schematically shown that the washer 203 includes 8 through holes 2031. Correspondingly, the washer 203 shown in FIG. 5 is suitable for a pin ring with 8 pin shafts 201 and 8 sleeves 202 2.

The gasket 203 also includes at least one sector section, which constitutes an annular gasket 203, and the contact surfaces of adjacent sector sections abut against each other to ensure the integrity of the gasket 203, wherein each of the sector sections The sector section includes at least two through holes 2031 . Referring to accompanying drawing 5, it shows the schematic structural diagram of this washer 203, schematically, this washer 203 comprises two sector sections, respectively is first sector section 2032 and second sector section 2033, and this first sector section Section 2032 has the same structure as the second sector section 2033, both of which are sector sections with a central angle of 180°, and the contact surfaces of the first sector section 2032 and the second sector section 2033 are two planes that abut against each other . In another embodiment, refer to FIG. 6 , which shows another way of combining the contact surfaces of the first sector 2032 and the second sector 2033 , wherein the end of the first sector 2032 The part is provided with a protrusion, and the end of the second sector 2033 is provided with a groove for receiving the protrusion, and the protrusion and the groove are configured to be connected by an interference fit, so as to ensure that the first The sector section 2032 is closely connected with the second sector section 2033 . Specifically, the sum of the number of through holes 2031 on the first sector 2032 and the second sector 2033 is equal to the number of through holes 2031, so that the gasket 203 can be placed between the lower polishing unit S and each sleeve 202 Between to protect the pin ring 2 and polishing equipment. In another embodiment of the present invention, referring to accompanying drawing 7, the pin ring 2 is composed of a sector section with a central angle of 360°, that is, the washer 203 is an integral ring, and the washer 203 is a component. When assembling the washer 203 on the pin shaft, the assembling steps can be simplified and the assembling efficiency can be improved. When assembling the double-sided polishing equipment, the through hole 2031 is aligned with the pin shaft 201, wherein the circumferential spacing between the adjacent through holes 2031 is equal to that of the adjacent pin shaft 201 along the circumferential direction, that is, when the After any two through holes 2031 on the washer 203 are aligned with their corresponding pin shafts 201 , the other through holes 2031 can also be directly aligned with their corresponding pin shafts 201 , so that the washer 203 and the pin shaft 201 can be easily assembled.

Preferably, in order to further ensure that the gasket 203 can line the bottom of the sleeve 202 to protect the sleeve 202 and the lower polishing unit S, and prevent the polishing unit from being worn, the fan-shaped section further includes an extension 2034, and the extension 2034 Set on the outer periphery of the corresponding through hole 2031, the extension 2034 surrounds the through hole 2031 and extends outward in the radial direction of the through hole 2031, see accompanying drawing 8, which shows a schematic diagram of the extension 2034, the extension 2034 Extend radially outward along the through hole 2031 to form a substantially circular ring shape, wherein the length of the extending portion 2034 along its extending direction is greater than or equal to the thickness of the sleeve 202, where the thickness of the sleeve 202 refers to is the thickness of the sleeve 202 along the radial direction. The extension part 2034 is preferably made integrally with the fan-shaped section to ensure that the extension part 2034 is coaxial with the through hole 2031, so that the extension part 2034 can accurately correspond to the bottom of the sleeve 202, and at the same time simplify the The manufacturing process of the gasket 203.

A pin ring 2 for double-sided polishing equipment disclosed in the embodiment of the present invention, the gasket 203 is composed of a fan-shaped section with a central angle of 360°, that is, the gasket 203 is a complete single ring-shaped part, the gasket 203 The assembly method is: along the length direction of the pin shaft 201 (the direction perpendicular to the surface of the lower polishing unit S), the gasket 203 is fitted to the pin shaft 201, wherein the gasket 203 is configured so that when the gasket 203 is assembled When on the pin shafts 201 , each pin shaft 201 passes through a through hole 2031 and is accommodated in the through hole 2031 . When assembling the washer 203 to the pin shaft 201 through the above-mentioned structure, it is only necessary to align the pin shaft 201 with the through hole 2031 to complete the assembly of the washer 203 through a single vertical movement. At this time, the disassembly of the gasket 203 can be realized by a single movement in the vertical direction. Since the gasket 203 is a complete independent ring made of rubber, even if the gasket 203 is directly washed with a high-pressure water gun, the gasket 203 will not be damaged. 203's are damaged or lost.

The embodiment of the present invention also provides a double-sided polishing machine 3, the double-sided polishing machine 3 includes an upper polishing unit P and a lower polishing unit S for processing the surface of the silicon wafer, and a polishing unit for carrying the silicon wafer to move between the polishing units. Silicon wafer carrier disc C, the double-sided polishing machine 3 also includes the pin ring 2 disclosed in the above-mentioned embodiment, referring to accompanying drawing 9, which shows a top view of the lower polishing unit S of the double-sided polishing machine 3, where there is no The sleeve is shown, the number of the pin rings 2 is two, respectively the first pin ring 21 and the second pin ring 22, compared with the double-sided polishing equipment of the related art shown in accompanying drawings 1 to 3, The double-sided polishing machine 3 replaces the pin ring 1 with the pin ring 2 disclosed in the embodiment of the present invention, and replaces the scattered gaskets with an integrated gasket, thereby simplifying the assembly steps of the double-sided polishing machine 3 and saving assembly time , and during the maintenance of the double-sided polishing machine 3, the risk of washer loss is avoided.

Wherein, the first pin ring 21 is arranged on the surface of the lower polishing unit S coaxially with the lower polishing unit S, and the second pin ring 22 is arranged radially outward around the first pin ring 21 on the surface of the lower polishing unit S. On the surface of the lower polishing unit S, that is, the diameter of the second pin ring 22 is larger than that of the first pin ring 21 . The first pin ring 21 includes a first pin shaft 211 and a first washer 213, and the second pin ring 22 includes a second pin shaft 221 and a second washer 223. The gap between the first pin ring 21 and the second pin ring 22 moves, and the area between the first pin ring 21 and the second pin ring 22 forms a processing area of the silicon wafer. Wherein, the first sleeve in the first pin ring 21 and the second sleeve in the second pin ring 22 are both provided with driving teeth on the outside, and correspondingly, the silicon wafer carrier C is provided with driving teeth on the outside. The matching receiving teeth, the first pin ring 21 and the second pin ring 22 drive the silicon wafer carrying tray C to move through the engagement of the driving teeth with the receiving teeth.

It should be noted that: the technical solutions described in the embodiments of the present invention can be combined arbitrarily if there is no conflict.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present invention. All should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the patent application.

A: Subunit C: Wafer Carrier P: upper polishing unit S: lower polishing unit 1: pin ring 101:pin shaft 102: Sleeve 103: Gasket 2: pin ring 201:pin shaft 202: Sleeve 2021: Dimple 203: Gasket 2031: Through hole 2032: The first sector 2033: The second sector 2034: Extension 21: First pin ring 211: the first pin shaft 213: First washer 22: Second pin ring 221: the second pin shaft 223:Second washer 3: Double-sided polishing machine

Fig. 1 is the structural representation of double-sided polishing equipment in the related art; 2 is a top view of a lower polishing unit of a double-sided polishing device in the related art; Fig. 3 is a schematic cross-sectional view of two adjacent subunits in a pin ring in the related art; 4 is a cross-sectional view of a pin ring for double-sided polishing equipment according to an embodiment of the present invention; Fig. 5 is a schematic structural diagram of a washer used for a pin ring of double-sided polishing equipment according to an embodiment of the present invention; Fig. 6 is a schematic diagram of a butt joint structure of a gasket according to another embodiment of the present invention; Fig. 7 is a schematic structural view of a gasket according to another embodiment of the present invention; Fig. 8 is a schematic structural view of an extension part for double-sided polishing equipment according to an embodiment of the present invention; Fig. 9 is a top view of a lower polishing unit of a double-sided polishing machine according to an embodiment of the present invention.

203: Gasket

2031: Through hole

Claims (10)

A pin ring for double-sided polishing equipment, the pin ring comprising: A plurality of pin shafts, the plurality of pin shafts are evenly fixed on the lower polishing unit of the double-sided polishing device along the circumferential direction; a plurality of sleeves rotatably mounted on each of the plurality of pins; a washer disposed between the sleeve and the lower polishing unit, the washer includes a plurality of through holes through which each of the plurality of pin shafts passes, the through holes are configured to allow the plurality of pin shafts to pass through One of the pin shafts passes through, wherein the washer is configured into an annular shape composed of at least one sector section, and the sector section includes at least two through holes. The pin ring for double-sided polishing equipment as claimed in claim 1, wherein the number of the sector is one, and the number of the through holes on the sector is equal to the number of the pin shaft. The pin ring for double-sided polishing equipment according to claim 1 or 2, wherein the through hole is configured with an inner diameter greater than or equal to the diameter of the pin shaft. The pin ring for double-sided polishing equipment according to claim 1 or 2, wherein, the sector section further includes an extension extending radially outward around each through hole, and the extension extends radially The length is greater than or equal to the thickness of the sleeve in the radial direction. The pin ring for double-sided polishing equipment as claimed in claim 4, wherein the extension part is integrally formed with the washer. The pin ring for double-sided polishing equipment as claimed in claim 1 or 2, wherein the outer wall of the sleeve and the silicon wafer carrier plate are configured to engage in a toothed manner. The pin ring for double-sided polishing equipment as claimed in claim 1 or 2, wherein the pin shaft and the sleeve are made of hard materials. The pin ring for double-sided polishing equipment as claimed in claim 1 or 2, wherein the gasket is made of rubber. A double-sided polishing machine, the double-sided polishing machine includes: upper polishing unit; lower polishing unit; a silicon wafer carrier plate arranged between the polishing units; The pin ring for double-sided polishing equipment as described in any one of claims 1 to 8, the pin ring is installed on the lower polishing unit, and the pin ring is used to limit the silicon wafer carrier and drive the silicon The chip carrier disk rotates between the polishing units, wherein the number of the pin rings is two, respectively a first pin ring and a second pin ring, and the second pin ring is arranged radially outward around the first pin ring . The double-sided polishing machine as claimed in claim 9, wherein the silicon wafer carrying plate is between the first pin ring and the second pin ring by engaging with the first pin ring and the second pin ring Gap rotation.

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