KR102598098B1 - Polishing apparatus and substrate processing apparatus - Google Patents

Abstract

The polishing device includes a polishing table to which liquid is supplied to the upper surface and rotating around a central axis, a ring-shaped liquid receiving member disposed below the periphery of the polishing table, and a lower end portion mounted on the periphery of the polishing table. It has a cylindrical drain member extending toward the liquid receiving member.

Description

Polishing apparatus and substrate processing apparatus {POLISHING APPARATUS AND SUBSTRATE PROCESSING APPARATUS}

(referred to as reference)

This application claims priority to Japanese Patent Application No. 2018-070919 filed on April 2, 2018 and Japanese Patent Application No. 2018-080025 filed on April 18, 2018, the contents of which are here It is used in

The present invention relates to a polishing device and a substrate processing device.

Conventionally, a CMP (Chemical Mechanical Polishing) device is known as one of the substrate processing devices for processing substrates such as silicon wafers. This substrate processing apparatus includes a polishing unit (polishing device) that polishes the substrate, and a cleaning unit that cleans the substrate. As shown in Japanese Patent Application Laid-Open No. 2017-18930, the polishing device includes a polishing table and a polishing head also called a top ring. The polishing table has a polishing pad attached to its rotating upper surface.

In such a polishing device, an abrasive liquid (liquid) containing abrasive particles such as silica (SiO ₂ ) or ceria (CeO ₂ ) is supplied from a polishing liquid nozzle onto a rotating polishing table on which a polishing pad is attached. On the polishing table (polishing pad), the substrate held on the lower surface of the polishing head is rotated and pressed. By this pressurization, the substrate surface in contact with the polishing pad surface is created into a desired flat surface by both rotation of the polishing table and the polishing head in the presence of the abrasive liquid.

The substrate with the desired flat surface is conveyed to the cleaning unit and subjected to cleaning treatment. A gas mixture containing an inert gas such as nitrogen gas is supplied from an atomizer nozzle to the upper surface of the polishing pad after the substrate is transported. As a result, the polishing pad surface is cleaned and used for polishing the next substrate.

In the above polishing process, the polishing liquid supplied from the polishing liquid nozzle, the gas mixture liquid supplied from the atomizer nozzle, and the polishing debris generated by polishing are present on the polishing table. In order to dispose of the liquid containing the polishing debris, the polishing device is equipped with a drainage and exhaust structure.

The drainage and exhaust structure provided in the polishing apparatus of Japanese Patent Application Laid-Open No. 2017-18930 includes an abrasive liquid receiving pan (liquid receiving member) and a gas-liquid separator. This abrasive liquid receiving pan is provided near the outer periphery of the polishing table and is configured to catch the liquid that falls as the polishing table rotates. Additionally, this gas-liquid separator is configured to separate the gas-liquid while introducing the liquid into the abrasive liquid receiving pan and allowing the introduced liquid to fall.

Additionally, in the above polishing process, the temperature of the polishing table rises due to the generation of frictional heat accompanying polishing. For this reason, as shown in Japanese Patent Laid-Open No. 2007-222965, a heat medium flow path is formed within the polishing table for passing a heat medium such as water to adjust the temperature.

A thermal medium is supplied to one end of the thermal medium flow path via the shaft portion of the polishing table, and the supplied thermal medium flows toward the other end of the thermal medium flow path. Therefore, the polishing table can be cooled or heated while the heat medium flows through the heat medium flow path. The heat medium whose temperature has been adjusted in this way is discharged from the other end of the heat medium flow path and taken out to the outside via the shaft portion.

The loading and unloading of the heat medium into the polishing table is performed using a pipe provided in the rotation axis of the polishing table and having a rotary joint at the bottom, as shown in, for example, Japanese Patent Laid-Open No. 2016-16491. all. That is, a heating medium supply piping and a heating medium return piping are attached to this pipe, and these heating medium supply piping and a heating medium return piping are configured so that the heating medium is deposited and withdrawn via a rotary joint. . Additionally, this pipe is also used for piping power or signal conductors of sensors provided at the bottom of the polishing table.

However, in the conventional drainage and exhaust structure, an abrasive liquid receiving pan is provided near the outer periphery of the polishing table, and the liquid containing polishing debris that moves and falls as the polishing table rotates is simply received by the abrasive liquid receiving pan. It is structured so that For this reason, it has been desired to be able to more actively discharge liquid from the polishing table to the abrasive liquid receiving pan. If the liquid can be more actively discharged from the polishing table, mist, etc. existing around the polishing table can be discharged quickly, thereby improving the clean condition around the polishing table.

Additionally, the optimal temperature of the upper surface of the polishing table varies depending on the type of substrate or polishing rate, and it may be necessary to change the heat medium flow path within the polishing table or the material of the polishing table itself according to these specifications. In a conventional polishing table, the entire surface from the top side where the heat medium flow path is formed to the bottom side connected to the motor was integrated, so it was necessary to replace the entire surface. For this reason, there were drawbacks such as increased manufacturing costs.

The present invention has been made in view of the above circumstances, and provides a polishing device capable of actively discharging liquid existing on a polishing table, and a substrate processing device equipped with such a polishing device.

The present invention has been made in further consideration of the above circumstances, and provides a polishing device that can inexpensively change the specifications of a polishing table according to the purpose of temperature control, and a substrate processing device equipped with such a polishing device.

(1) A polishing device according to an aspect of the present invention includes a polishing table to which liquid is supplied to the upper surface and rotating about a central axis, a ring-shaped liquid receiving member disposed below a peripheral portion of the polishing table, and It is mounted on the periphery of the polishing table and has a cylindrical drain member whose lower end extends toward the liquid receiving member.

(2) The polishing device according to (1) above, wherein the liquid receiving member has an inner circumferential wall disposed radially inside a lower end of the drain member, and the lower end of the drain member is lower than the upper end of the inner circumferential wall. You can extend it to .

(3) The polishing device according to (1) or (2) above, wherein a step for mounting the drain member is formed on a peripheral portion of the polishing table, and the drain member is attached to the bottom surface of the step via a bolt. It is mounted and has a first seal member that seals a gap in the radial direction between the drain member and the side surface of the step, and a second seal member that seals an insertion hole of the drain member through which the bolt is inserted. It's okay too.

(4) The polishing device according to (1) to (3) above, wherein the polishing device is disposed radially outside the drain member and has a gap in the radial direction with the drain member toward the upper surface of the polishing table. It has a cover member that gradually becomes smaller, and a gas-liquid separation device that sucks gas through the liquid receiving member and separates liquid contained in the gas, wherein the gas-liquid separation device is between the drain member and the cover member. The gap formed may be used as a suction path.

(5) The polishing device according to (4) above, wherein the cover member is disposed with a gap between the outer circumferential wall of the liquid receiving member, and the gap size between the cover member and the outer circumferential wall is equal to that of the cover member. It may be smaller than the gap size with the upper end of the drainage member.

(6) In the polishing device according to (4) or (5) above, the cover may be movable in the vertical direction.

(7) A polishing apparatus according to an aspect of the present invention has a polishing table on which a substrate is pressed on an upper surface and rotates about a central axis, wherein the polishing table forms the upper surface and has a heat medium flow path therein. The branch has a table and a table base that detachably supports the table.

(8) The polishing device according to (7) above, comprising: a plurality of bolts for detachably fixing the periphery of the table to the periphery of the table base, and radially inside the plurality of bolts, You may have one or more knock pins for positioning the table.

(9) The polishing device according to (8) above, which has a cylindrical drain member covering a dividing surface between the table and the table base from a radial direction, and the drain member is subjected to the polishing by the plurality of bolts. It may be detachably mounted on the periphery of the table.

(10) The polishing device according to (7) to (9) above, wherein a cylindrical flange rotationally driven by a motor is connected to the lower surface of the table base, and the flange is connected to the lower surface of the table base. A space for mounting a film thickness measuring device that measures the film thickness of the substrate may be formed.

(11) In the polishing device according to (7) to (10) above, a ring-shaped drainage protrusion protruding downward may be formed on the lower surface side of the peripheral portion of the table base.

(12) In the polishing device according to (7) to (11) above, a coating layer to which a polishing pad is peelably adhered may be formed on the upper surface of the table.

(13) In the polishing device according to (12) above, the coating layer may be a fluororesin coating layer.

(14) In the polishing device according to (12) above, the coating layer may be a glass coating layer.

(15) In the polishing device according to (12) above, the coating layer may be a ceramic coating layer.

(16) In the polishing device according to (12) above, the coating layer may be a diamond coating layer.

(17) A substrate processing apparatus according to one aspect of the present invention is a substrate processing apparatus having a polishing unit for polishing a substrate and a cleaning unit for cleaning the substrate polished by the polishing unit, wherein the polishing unit includes the ( The polishing device described in 1) to (16) is provided.

According to the above aspect of the present invention, a cylindrical drain member whose lower end extends toward the liquid receiving member is provided at the periphery of the polishing table, so that liquid can be efficiently guided to the liquid receiving member from the upper surface of the polishing table, The clean condition around the polishing table can be improved.

Furthermore, according to the above aspect of the present invention, since the table having the heat medium flow path is detachably supported on the table base, only the portion of the table having the heat medium flow path can be exchanged depending on the purpose of temperature control. The specifications of the polishing table can be changed inexpensively.

1 is a configuration diagram of a polishing table and its surrounding structure included in a polishing apparatus according to a first embodiment of the present invention.
FIG. 2 is an enlarged view of portion A of FIG. 1.
Fig. 3 is a perspective view of an abrasive liquid reservoir provided in the polishing device according to the first embodiment of the present invention.
Fig. 4 is a cross-sectional view of a gas-liquid separation device included in the polishing device according to the first embodiment of the present invention.
Fig. 5 is a plan view showing the overall configuration of the substrate processing apparatus according to the first embodiment of the present invention.
Fig. 6 is a configuration diagram of a polishing table and its surrounding structure included in the polishing apparatus according to the second embodiment of the present invention.
Fig. 7 is a plan view of a polishing table according to a second embodiment of the present invention.
Fig. 8 is an explanatory diagram showing the internal structure of a shaft according to the second embodiment of the present invention.
FIG. 9 is a schematic perspective view showing the overall configuration of the polishing unit shown in FIG. 5.
Fig. 10 is a cross-sectional view showing the attachment structure of the polishing pad according to the second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A polishing device and a substrate processing device according to an embodiment of the present invention will be described below with reference to the drawings. In addition, the embodiment shown below is explained as an example in order to better understand the spirit of the invention, and does not limit the invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make it easier to understand the features of the present invention, major parts may be enlarged for convenience, and the dimensional ratios of each component are limited to being the same as in reality. I can't. Additionally, in order to make the features of the present invention easier to understand, some parts have been omitted for convenience.

<First embodiment>

(polishing device)

FIG. 1 is a configuration diagram of a polishing table 1 and its surrounding structure included in a polishing apparatus according to an embodiment. FIG. 2 is an enlarged view of portion A of FIG. 1.

This polishing device is included as part of a substrate processing device (described later) that processes semiconductor substrates such as silicon wafers. This polishing device is comprised of a polishing table 1, a top ring, etc., but only a portion of the polishing table 1 is shown here.

In the following description, before explaining the substrate processing apparatus, the polishing table 1 and its surrounding structure (drain exhaust structure 10) of the polishing apparatus, which is the main part of the present invention, will be explained.

The polishing table 1 shown in FIG. 1 has a circular upper surface and rotates around a central axis L passing through the center of the circular shape. This polishing table 1 has a table 2 located on the upper surface side, and a table base 3 on which the table 2 is stacked. Additionally, a polishing pad is attached to the upper surface of the table 2, but is omitted here. An opening corresponding to the sensor hole 2h provided in the table 2, which will be described later, is formed in the polishing pad.

The material of the table 2 is selected from the viewpoint of thermal conductivity and ease of processing, and is, for example, made of stainless steel, ceramic, or aluminum alloy. This table 2 is formed by vertically joining the first table part 2a located above and the second table part 2b located below the first table part 2a.

A heat medium flow path 4 is formed in the second table portion 2b. The heat medium flow path 4 is the upper surface of the second table portion 2b, and is a concave groove formed to cover approximately the entire upper surface. The first table portion 2a is a plate body (cover body) that is joined to the upper surface of the second table portion 2b and closes the upper surface opening of the concave groove of the heat medium flow passage 4. A heat medium (temperature control water, etc.) is supplied to this heat medium flow path 4 from the rotary joint 9a side, which will be described later, via the shaft 9.

A step 2c is provided on the upper surface side of the peripheral portion of the table 2. The depth of this step 2c is determined by the thickness of the springer 11 (drainage member) and the head portion of the bolt 2d for attaching the springer 11 and the table 2 to the table base 3. The total height is determined to be below the upper surface position of the first table portion 2a. In this embodiment, the springer 11 is one of the structural members of the drainage exhaust structure 10.

As shown in Fig. 2, a seal washer 2d1 (second seal member) is fitted between the head of the bolt 2d and the springer 11. The seal washer 2d1 prevents the liquid on the table 2 from entering the table base 3 side through the insertion hole of the springer 11 through which the bolt 2d is inserted.

On the side of the step 2c provided on the table 2, a concave groove is provided that is concave inward in the radial direction, and an O-ring 2f (first seal member) is disposed in this concave groove. The O-ring 2f abuts the inner end surface of the springer 11 mounted on the step 2c. The O-ring 2f seals the gap in the radial direction between the springer 11 and the side surface of the step 2c, and the liquid on the table 2 flows to the table base 3 side through the gap. Prevent intrusion.

Returning to Fig. 1, one or a plurality of knock pin holes 2g are provided on the lower surface of the table 2 at a predetermined distance from each other on the same radius. In addition, in Fig. 1, only one knock pin hole 2g is shown among a plurality (for example, three) knock pin holes 2g. The installation location of this knock pin hole 2g corresponds to the knock pin 3b provided in the table base 3, which will be described later. Additionally, the table 2 is provided with a sensor hole 2h penetrating in the vertical direction at a position radially away from the central axis L.

The table base 3 can be made of a material having sufficient rigidity, for example, the above-mentioned SUS304 or ceramic. However, if it is made of ceramic, it may be expensive. Additionally, from the viewpoint of density, ease of processing, etc., it can also be made of, for example, an aluminum alloy. For example, the above-mentioned A6061P aluminum alloy for forging or AC4CH aluminum alloy casting are suitable.

The upper surface of the table base 3, that is, the surface in contact with the bottom surface (lower surface) of the table 2, is formed in a circular shape similar to that of the table 2. Additionally, when this table base 3 is viewed from the front side, it is formed in an inverted trapezoid. And, on the bottom surface side of the peripheral portion of the table base 3 and radially inside the fastening position of the bolt 2d, an annular drainage protrusion 3a protruding downward is integrally formed. there is.

As shown in FIG. 2, on the upper surface of the table base 3, radially inside the bolt 2d, one or a plurality of knock pins 3b are provided at a predetermined distance from each other on the same radius. It is installed so that it protrudes toward (2). In addition, in Fig. 1, only one knock pin 3b is shown among a plurality (for example, three) knock pins 3b. These knock pins 3b are provided opposing the knock pin holes 2g provided in the table 2 described above. The table 2 and the table base 3 are positioned by inserting the knock pin 3b into the knock pin hole 2g, and are fastened together with the springer 11 by the bolt 2d, It is integrated so that it can rotate around the central axis (L).

Additionally, the table base 3 is provided with a sensor mounting portion 3c. This sensor mounting portion 3c is provided on the table 2 when the knock pin 3b of the table base 3 is inserted into the knock pin hole 2g of the table 2 and both are positioned and stacked. It is provided in a position opposite to the sensor hole 2h. This sensor mounting portion 3c is equipped with a wafer film thickness detector (film thickness measuring device) 5 that detects the flat surface state of a substrate (not shown) to be polished on the polishing table 1. The wafer film thickness detector 5 is in watertight contact with the sensor hole 2h.

Additionally, a flange 6 is connected to the central portion of the bottom surface of the table base 3. The flange 6 is made of a cylindrical body, and its upper end is fixed to the table base 3 using a bolt 6a. The length of the flange 6 in the axial direction is set to a length extending downward from the lower end position of the wafer film thickness detector 5 mounted on the table base 3. Therefore, this flange 6 also serves to secure space for mounting the wafer film thickness detector 5 on the table base 3.

A motor 7 is connected to the lower end of the flange 6. The motor 7 has a hollow motor rotation shaft 7a, and the upper end of the motor rotation shaft 7a is fixed to the lower end of the flange 6 using a bolt 6b. Additionally, the motor casing 7b of this motor 7 is fixed to the frame 8 on the fixed side of the polishing device. That is, the polishing table 1 is supported on the frame 8 via the motor 7 and the flange 6. And, when the motor 7 is driven to rotate, the polishing table 1 is rotated with a bolt ( 2d), the table 2 can be rotated around the central axis L.

The upper end of the shaft 9 passing through the hollow motor rotation shaft 7a of the motor 7 is connected to the center of the bottom surface of the polishing table 1. The lower end of the shaft 9 is connected to the rotary joint rotation shaft 9d of the rotary joint 9a via a coolant flange 9e fixed to the lower end of the motor rotation shaft 7a. Therefore, the shaft 9 above the rotary joint 9a can rotate together with the table 2.

The rotary joint 9a is connected to a heat medium supply pipe 9b that supplies heat medium to the shaft 9 side and a heat medium return pipe 9c that returns the heat medium discharged from the shaft 9 side. It is done. Additionally, within the shaft 9, although not shown, there is a pipe for supplying the heat medium supplied to the shaft 9 to one end of the heat medium flow path 4 in the table 2, and a heat medium flow path 4. A pipe is formed to return the heat medium discharged from the other end to the rotary joint 9a side.

Therefore, when a thermal medium is supplied to the thermal medium supply pipe 9b of the rotary joint 9a, the supplied thermal medium passes through the thermal medium flow path 4 in the table 2 and again into the rotary joint 9a. It returns to the heat medium return pipe (9c). In this way, by supplying a heat medium through the rotary joint 9a, the upper surface of the table 2 can be adjusted to a desired temperature even if it is rotating.

Next, the drainage exhaust structure 10 will be described with reference to FIGS. 3 and 4 as well.

As shown in FIG. 2, the drainage exhaust structure 10 includes a springer 11 (drainage member), a cover 20 (cover member), an abrasive liquid reservoir 30 (liquid reservoir member), and a gas-liquid reservoir. It consists of a separation device 40 (see FIG. 1).

As described above, the springer 11 shown in FIG. 1 is provided at the step 2c of the table 2, and its overall shape is formed into a cylindrical shape that can cover the entire side surface of the table 2. It is done. The vertical cross-sectional shape of the springer 11 is an L-shaped top and bottom, and the upper curved portion of the shape is mounted on the step 2c of the table 2. In addition, the length of the part vertically descending from the curved part is determined to extend downward from the lower end of the draining projection 3a provided on the table base 3.

Next, the cover 20, the abrasive liquid receiver 30, and the gas-liquid separation device 40 attached to the polishing table 1 having the above-described structure will be described.

The cover 20 is provided on the fixed frame side of the polishing device, not shown, and its overall shape is such that it can cover the entire side of the springer 11 at a position radially outside the springer 11. It is formed in a cylindrical shape. The cover 20 is formed so that the gap in the radial direction between the cover 20 and the springer 11 becomes gradually smaller as it moves toward the upper surface of the polishing table 1. Specifically, when the gap size at the upper surface of the polishing table 1 is S1 and the gap size at the lower end of the springer 11 is S2, there is a relationship of S1 < S2.

That is, the cover 20 is located at a predetermined distance radially outward from the springer 11, and its inner circumference is inclined (axially diametrically) to slightly incline toward the center of the cylindrical shape. Additionally, the length of the cylindrical cover 20 in the axial direction is sufficiently longer than the length of the portion extending vertically from the curved portion of the springer 11. Accordingly, the gap formed between the springer 11 and the cover 20 forms a kind of orifice structure that narrows as it moves upward.

This cover 20 is movable in the vertical direction (axial direction), as indicated by the two-dot chain line. This movement in the vertical direction is performed by an actuator provided on the fixed frame side of the polishing device, not shown, but can also be performed manually. The solid line in FIG. 2 indicates a state in which the cover 20 has moved upward and is in a state where it can receive the abrasive liquid or gas mixture liquid discharged from the upper surface side of the table 2. Meanwhile, the two-dot chain line in FIG. 2 indicates a state in which the cover 20 has moved downward. The downward movement of the cover 20 is performed when replacing the polishing pad attached to the table 2 or during maintenance work on the polishing head, also called a top ring, and the table 2.

The abrasive liquid receiver 30 is provided on the fixed frame side of the polishing device, not shown, and has a trough 31 (see FIG. 3) having a circular opening at the top. As shown in FIG. 2, the outer peripheral wall 31a on the radial outer side of the gutter 31 is disposed radially outer than the lower end of the cover 20, so that the cover 20 is maintained even when the cover 20 moves up or down. ) is designed to overlap with the lower part of the. Additionally, if the gap size between the cover 20 and the outer peripheral wall 31a when the cover 20 moves upward is S3, the relationship is S3 < S1 < S2. S3 can be made sufficiently small. As a result, the inflow of external air into the inside of the trough 31 is suppressed, and the suction efficiency of the gas-liquid separation device 40 described later is improved.

In addition, including the exhaust treatment device (suction device), not shown, connected to the exhaust pipe 45, which will be described later, when S3 is small, air from the motor side is introduced rather than outside air. As a result, since the polishing liquid flows down roughly as shown by the arrow, it becomes difficult for the polishing liquid to flow into the motor side, and it also becomes difficult for the polishing liquid to enter the gap between the parts where the member is fastened.

On the other hand, the inner peripheral wall 31b on the radial inner side of the gutter 31 is disposed radially inner than the lower end of the springer 11. The lower end of the springer 11 extends downward than the upper end of the inner peripheral wall 31b, and the two overlap. Therefore, a kind of labyrinth structure can be formed by the springer 11 and the inner peripheral wall 31b of the abrasive liquid receiver 30. As a result, it is possible to prevent gas and liquid from flowing into the inner peripheral wall 31b of the abrasive liquid receiver 30 in the radial direction, that is, toward the bottom surface of the table base 3.

As shown in FIG. 3, a drain tank 32 is provided in a part of the trough 31, and is configured to collect liquid such as abrasive fluid in the trough 31. The liquid collected here is configured to be guided to the gas-liquid separation device 40 through the discharge pipe 33 provided on the bottom wall of the drain tank 32. Additionally, the upper opening of the drain tank 32 is closed by the cover member 32a. The cover member 32a is provided with a mounting pin (not shown) inserted into a mounting hole 32b provided in the drain tank 32.

As shown in FIG. 4 , the gas-liquid separation device 40 has a space with a predetermined capacity inside, and a gas-liquid separation cylinder 41 is built into the space. This gas-liquid separation container 41 is mounted so that its upper part surrounds the opening of the discharge pipe 33 connected to the abrasive liquid receiver 30, and an inclined collision plate 42 is provided at a position opposite to the opening. ) is installed. Additionally, an opening 43 is provided at a location of the gas-liquid separation tank 41 opposite the collision plate 42.

The collision plate 42 is divided into an upper collision plate 42a and a lower collision plate 42b. Among these, the upper end of the upper impingement plate 42a is fixed to the inner wall side of the gas-liquid separation device 40, and the lower impingement plate 42b is slidably mounted on the lower side of the upper impingement plate 42a. there is. Therefore, the collision plate 42 can adjust the length at which the gas-liquid mixture discharged from the discharge pipe 33 of the abrasive liquid receiver 30 touches the collision plate 42.

The gas-liquid separation device 40 is configured to separate gas and liquid within the space, and is provided with a drain pipe 44 and an exhaust pipe 45. Among these, the drainage pipe 44 is provided at the bottom of the gas-liquid separation device 40 and is configured to discharge the liquid separated by the gas-liquid separation device 40 to a drainage treatment device not shown. Additionally, the exhaust pipe 45 is located at the top of the gas-liquid separation device 40 and is provided on the side opposite to the side where the opening 43 of the gas-liquid separation cylinder 41 is provided. Therefore, since the position of the exhaust pipe 45 is the longest distance from the position of the opening 43, the liquid accompanying the airflow flowing through the exhaust pipe 45 can be reduced. Additionally, this exhaust pipe 45 is connected to an exhaust treatment device (suction device), not shown.

When polishing a substrate such as a silicon wafer on the polishing table 1 having the above configuration, a polishing pad is attached to the upper surface of the table 2. Additionally, a substrate is mounted on the lower surface of the top ring (polishing head). Then, when the motor 7 rotates, the table 2 on which the polishing pad is attached rotates via the flange 6 and the table base 3.

On the polishing pad, an abrasive liquid containing abrasive grains such as silica (SiO ₂ ) and ceria (CeO ₂ ) is supplied from a polishing liquid nozzle (not shown), and the lower surface of the top ring is applied to the upper surface of the polishing pad to which the abrasive liquid is supplied. The substrate held in rotates and is pressurized. By this pressurization, the substrate surface in contact with the polishing pad surface is created into a desired flat surface by both rotation of the polishing table 1 and the polishing head in the presence of the abrasive liquid.

When the wafer film thickness detector 5 detects that the polished surface of the substrate is a desired flat surface, i.e., has a desired film thickness, the substrate is transferred to the cleaning device of the next substrate processing device and subjected to cleaning treatment. A gas mixture containing an inert gas such as nitrogen gas is supplied from an atomizer nozzle (not shown) onto the rotating polishing pad after the substrate is transported. As a result, the upper surface of the polishing pad is cleaned and used for polishing the next substrate to be polished.

As described above, the abrasive liquid is supplied from the polishing liquid nozzle to the upper surface of the rotating table 2 with the polishing pad attached, and the gas mixture liquid is supplied from the atomizer nozzle, so that the abrasive liquid is supplied from around the upper surface of the table 2. The abrasive liquid, the abrasive liquid containing polishing debris, the gas mixture liquid, or the gas mixture liquid containing polishing debris, or the mist of these liquids are discharged. In addition, in the present invention, when simply referred to as “liquid,” it includes various substances discharged from the upper surface of the polishing table 1.

As indicated by arrows in FIG. 2, part of the liquid discharged from the upper surface of the table 2 of the polishing table 1 falls along the outer peripheral surface of the springer 11, and part falls inside the cover 20. After being received on the wall, it falls along the inner wall and is received in the abrasive liquid receiver 30. In addition, the gas-liquid separation device 40 uses the gap formed between the springer 11 and the cover 20 as a suction flow path, and since the gap forms a kind of orifice structure, a descending airflow faster than the surroundings ( flow rate) is generated. Accordingly, the liquid about to be discharged from the upper surface of the table 2 can quickly and efficiently move to the abrasive liquid receiver 30 through the portion of the orifice structure. Thereby, the clean condition around the polishing table 1 can be further improved. Additionally, in order to facilitate the movement of liquid in the springer 11 and the cover 20, their materials or surfaces may be rich in hydrophilic or water-repellent properties.

In addition, since the inner peripheral wall 31b of the springer 11 and the abrasive liquid receiver 30 forms a kind of labyrinth structure, it is possible to prevent gas and liquid from flowing into the bottom surface side of the table base 3. . Accordingly, it is possible to prevent the wafer film thickness detector 5 and the motor 7 disposed on the bottom surface side of the table base 3 from being exposed to water. In addition, since a drainage projection 3a protruding downward is provided integrally near the outer periphery of the bottom surface of the table base 3, liquid attempting to move to the center of the table base 3 can be effectively blocked. there is.

(Substrate processing device)

Next, a substrate processing apparatus 100 including a polishing apparatus having the above configuration will be described.

FIG. 5 is a plan view showing the overall configuration of the substrate processing apparatus 100 according to one embodiment.

The substrate processing apparatus 100 shown in FIG. 5 is a chemical mechanical polishing (CMP) apparatus that polishes the surface of a substrate W such as a silicon wafer to a flat surface. This substrate processing apparatus 100 is provided with a housing 102 in the shape of a rectangular box. The housing 102 is formed into a substantially rectangular shape when viewed from the top.

The housing 102 is provided with a substrate transport path 103 extending in the longitudinal direction at its center. A load/unload portion 110 is disposed at one end of the substrate transport path 103 in the longitudinal direction.

A polishing section 120 is disposed on one side of the substrate transport path 103 in the width direction (a direction perpendicular to the longitudinal direction in plan view), and a cleaning section 130 is disposed on the other side. The substrate transport path 103 is provided with a substrate transport unit 140 that transports the substrate W. In addition, the substrate processing apparatus 100 includes a control unit 150 (control panel) that controls the operations of the load/unload unit 110, the polishing unit 120, the cleaning unit 130, and the substrate transfer unit 140. Equipped with

The load/unload unit 110 includes a front load unit 111 that accommodates the substrate W. A plurality of front rod portions 111 are provided on one side of the housing 102 in the longitudinal direction. The plurality of front rod portions 111 are arranged in the width direction of the housing 102. The front load unit 111 mounts, for example, an open cassette, a Standard Manufacturing Interface (SMIF) pod, or a Front Opening Unified Pod (FOUP). SMIF and FOUP are sealed containers that store the cassette of the substrate W inside and are covered with a partition wall, and can maintain an environment independent of external space.

In addition, the load/unload unit 110 includes two transfer robots 112 for loading and unloading the substrate W from the front load unit 111, and each transfer robot 112 in a row of the front load unit 111. It is provided with a traveling mechanism 113 that causes it to travel along. Each transfer robot 112 is equipped with two hands, upper and lower, and is used separately before and after processing the substrate W. For example, the upper hand is used when returning the substrate W to the front load unit 111, and the lower hand is used when removing the unprocessed substrate W from the front load unit 111.

The polishing unit 120 includes a plurality of polishing units 121 (121A, 121B, 121C, 121D) that polish (flatten) the substrate W. A plurality of polishing units 121 are arranged in the longitudinal direction of the substrate transport path 103 . The polishing unit 121 includes a polishing table 123 that rotates a polishing pad 122 having a polishing surface, a substrate W, and a polishing pad 122 on the polishing table 123 to hold the substrate W. A top ring 124 for polishing while pressing, a polishing liquid supply nozzle 125 for supplying polishing liquid or dressing liquid (for example, pure water) to the polishing pad 122, and polishing of the polishing pad 122. A dresser 126 for dressing the surface, and a mixture of a liquid (for example, pure water) and a gas (for example, nitrogen gas) or a liquid (for example, pure water) in a mist state to spray the polishing surface. An atomizer (127) is provided.

The polishing unit 121 supplies polishing liquid onto the polishing pad 122 from the polishing liquid supply nozzle 125, presses the substrate W against the polishing pad 122 with the top ring 124, and further presses the top ring 124 onto the polishing pad 122. By moving 124 and the polishing table 123 relative to each other, the substrate W is polished and its surface is flattened. In the dresser 126, hard particles such as diamond particles or ceramic particles are fixed to a rotating part at the tip that contacts the polishing pad 122, and the rotating part oscillates to cover the entire polishing surface of the polishing pad 122. Dress uniformly to form a flat polished surface. The atomizer 127 cleans the polishing surface by washing away polishing debris and abrasive grains remaining on the polishing surface of the polishing pad 122 with a high-pressure fluid, and cleans the polishing surface by the dresser 126, which is mechanical contact. Sharpening operations, i.e. regeneration of the polished surface, are achieved.

The cleaning unit 130 includes a plurality of cleaning units 131 (131A, 131B) that clean the substrate W, and a drying unit 132 that dries the cleaned substrate W. A plurality of cleaning units 131 and drying units 132 (a plurality of processing units) are arranged in the longitudinal direction of the substrate transport path 103 . A first transfer chamber 133 is provided between the cleaning unit 131A and the cleaning unit 131B. The first transfer chamber 133 is provided with a transfer robot 135 that transfers the substrate W between the substrate transfer unit 140, the cleaning unit 131A, and the cleaning unit 131B. Additionally, a second transfer chamber 134 is provided between the cleaning unit 131B and the drying unit 132. The second transfer chamber 134 is provided with a transfer robot 136 that transfers the substrate W between the cleaning unit 131B and the drying unit 132.

The cleaning unit 131A includes, for example, a roll sponge-type cleaning module and performs primary cleaning of the substrate W. Additionally, the cleaning unit 131B also includes a roll sponge type cleaning module and performs secondary cleaning of the substrate W. Additionally, the cleaning unit 131A and the cleaning unit 131B may be of the same type or different types of cleaning modules, for example, a pencil sponge type cleaning module or a two-fluid jet type cleaning module. The drying unit 132 includes, for example, a drying module that performs rotagoni drying (IPA (Iso-Propyl Alcohol) drying). After drying, the shutter 101a provided on the partition between the drying unit 132 and the load/unload unit 110 is opened, and the substrate W is taken out from the drying unit 132 by the transfer robot 112. .

The substrate transport unit 140 includes a lifter 141, a first linear transporter 142, a second linear transporter 143, and a swing transporter 144. In the substrate transfer path 103, there are a first transfer position (TP1), a second transfer position (TP2), a third transfer position (TP3), and a fourth transfer position (TP4) in that order from the load/unload unit 110 side. , the 5th conveyance position TP5, the 6th conveyance position TP6, and the 7th conveyance position TP7 are set.

The lifter 141 is a mechanism that transports the substrate W up and down at the first transport position TP1. The lifter 141 receives the substrate W from the transfer robot 112 of the load/unload unit 110 at the first transfer position TP1. Additionally, the lifter 141 transfers the substrate W received from the transfer robot 112 to the first linear transporter 142 . A shutter 101b is provided on the partition wall between the first transfer position TP1 and the load/unload unit 110, and when the substrate W is transferred, the shutter 101b is opened to release the lifter from the transfer robot 112. The substrate (W) is delivered to (141).

The first linear transporter 142 transports the substrate W between the first transport position TP1, the second transport position TP2, the third transport position TP3, and the fourth transport position TP4. It is a device that does The first linear transporter 142 includes a plurality of transfer hands 145 (145A, 145B, 145C, 145D) and a linear guide mechanism 146 that moves each transfer hand 145 in the horizontal direction at a plurality of heights. is provided. The conveyance hand 145A moves between the first conveyance position TP1 and the fourth conveyance position TP4 by the linear guide mechanism 146. This transport hand 145A is a pass hand for receiving the substrate W from the lifter 141 and delivering it to the second linear transporter 143. This conveyance hand 145A is not provided with a lifting/lowering driving part.

The conveyance hand 145B moves between the first conveyance position TP1 and the second conveyance position TP2 by the linear guide mechanism 146. This transfer hand 145B receives the substrate W from the lifter 141 at the first transfer position TP1 and delivers the substrate W to the polishing unit 121A at the second transfer position TP2. . The transfer hand 145B is provided with a lifting and lowering drive unit, and rises when delivering the substrate W to the top ring 124 of the polishing unit 121A, and descends after delivering the substrate W to the top ring 124. In addition, the conveyance hand 145C and the conveyance hand 145D are also provided with similar lifting/lowering driving parts.

The conveyance hand 145C moves between the first conveyance position TP1 and the third conveyance position TP3 by the linear guide mechanism 146. This transfer hand 145C receives the substrate W from the lifter 141 at the first transfer position TP1 and delivers the substrate W to the polishing unit 121B at the third transfer position TP3. . Additionally, the transfer hand 145C receives the substrate W from the top ring 124 of the polishing unit 121A at the second transfer position TP2, and transfers the substrate W to the polishing unit 121B at the third transfer position TP3. It also functions as an access hand for transferring the substrate W.

The conveyance hand 145D moves between the second conveyance position TP2 and the fourth conveyance position TP4 by the linear guide mechanism 146. The transfer hand 145D receives the substrate W from the top ring 124 of the polishing unit 121A or the polishing unit 121B at the second transfer position TP2 or the third transfer position TP3, and 4 It functions as an access hand for transferring the substrate W to the swing transporter 144 at the transfer position TP4.

The swing transporter 144 has a hand that can move between the fourth transport position TP4 and the fifth transport position TP5, and moves from the first linear transporter 142 to the second linear transporter 143. Transfer the substrate (W) to. Additionally, the swing transporter 144 transfers the substrate W polished in the polishing unit 120 to the cleaning unit 130 . On the side of the swing transporter 144, a temporary stand for the substrate W is provided. The swing transporter 144 inverts the substrate W received at the fourth transfer position TP4 or the fifth transfer position TP5 up and down and mounts it on a temporary stand. The substrate W mounted on the temporary stand is transferred to the first transfer chamber 133 by the transfer robot 135 of the cleaning unit 130.

The second linear transporter 143 is a mechanism that transports the substrate W between the fifth transport position TP5, the sixth transport position TP6, and the seventh transport position TP7. The second linear transporter 143 is provided with a plurality of transfer hands 148 (148A, 148B, 148C) and a linear guide mechanism 149 that moves each transfer hand 145 in the horizontal direction at a plurality of heights. do. The conveyance hand 148A moves between the fifth conveyance position TP5 and the sixth conveyance position TP6 by the linear guide mechanism 149. The transport hand 145A functions as an access hand that receives the substrate W from the swing transporter 144 and delivers it to the polishing unit 121C.

The conveyance hand 148B moves between the 6th conveyance position TP6 and the 7th conveyance position TP7. The transfer hand 148B functions as an access hand for receiving the substrate W from the polishing unit 121C and transferring it to the polishing unit 121D. The conveyance hand 148C moves between the 7th conveyance position TP7 and the 5th conveyance position TP5. The transfer hand 148C receives the substrate W from the top ring 124 of the polishing unit 121C or the polishing unit 121D at the sixth transfer position TP6 or the seventh transfer position TP7, and 5 It functions as an access hand for transferring the substrate W to the swing transporter 144 at the transfer position TP5. Although description is omitted, the operation of the transfer hand 148 when transferring the substrate W is the same as the operation of the first linear transporter 142 described above.

Also in the substrate processing apparatus 100 having the above configuration, the polishing table 1 of the present invention and its drainage exhaust structure 10 are applied to the polishing table 123 of the polishing unit 121 (polishing device). , the clean condition around the polishing table 123 can be further improved.

<Second Embodiment>

(polishing device)

FIG. 6 is a configuration diagram of the polishing table 1 and its surrounding structure included in the polishing apparatus according to one embodiment. Fig. 7 is a top view of the polishing table 1 according to one embodiment. Fig. 8 is an explanatory diagram showing the internal structure of the shaft 9 according to one embodiment.

In this embodiment, different parts will be explained based on the polishing device of the first embodiment, and description of the same members will be omitted.

A thermal medium (temperature control water, etc.) is supplied to the thermal medium flow path 4 of the present embodiment from the rotary joint 9a side, which will be described later, via the shaft 9, and the thermal medium is as shown in FIG. 7. , is supplied from the supply port 2A at the center of the table 2, and discharged from the two discharge ports 2B at the center of the table 2. Specifically, the heat medium is supplied from the supply port 2A, flows toward the radial outer side of the table 2, and branches radially inward and radially outward in the middle portion 2I, After circulating through the radial inside and radial outside of the table 2, respectively, it is discharged from the two discharge ports 2B. Thereby, the temperature of the upper surface of the table 2 can be efficiently equalized.

In the polishing table 1, since substantially the entire upper surface of the table 2 is used for polishing, equalization of the temperature of the upper surface of the table 2 is important as a polishing condition. Additionally, uniformity of the temperature of the upper surface of the table 2 is also important from the viewpoint of extending the life of the polishing table 1 and the polishing pad (not shown). That is, for example, if the temperature of the upper surface of the table 2 cannot be uniformized and the temperature distribution becomes large, there will be a difference in local expansion and contraction of the coating film (not shown) of the table 2, and further, a difference between the coating film and the table (2) ), the difference in local expansion and contraction between the two increases, and as a result of the deterioration of the membrane, it becomes a factor in cracking or peeling.

The following materials are suitable for the table 2. For example, if the material of the table 2 is SiC (silicon carbide), the minimum tensile strength is 450 (MPa), which is excellent in processability and sufficient mechanical strength, and the thermal conductivity is also 170 (W/(m·K)) ) is high, making it suitable for temperature control.

Additionally, the table 2 can also be made of aluminum, which is easy to machine. For example, if the material of the table 2 is A6061P aluminum alloy plate, the minimum tensile strength is 310 (MPa), which is excellent in processability and sufficient mechanical strength, and the thermal conductivity is also 167 (W/(m·K)). It is high and suitable for temperature control.

In addition, for example, when the material of the table 2 is AC4CH aluminum alloy casting, the minimum tensile strength is 230 (MPa), which provides excellent workability and sufficient mechanical strength, and the thermal conductivity is also 151 (W/(m· K)) is high, making it suitable for temperature control. In contrast, in the case of SUS304, which is common as a mechanical material, the minimum tensile strength is 520 (MPa), which has sufficient mechanical strength, but the thermal conductivity is low at 17 (W/(m·K)), and in addition, the heat medium flow path in Priceban is low. Since it requires advanced machining, such as forming (4), it cannot be said to be a material with excellent processability, but its toughness is high, making it an option.

A step 2c is provided on the upper surface side of the peripheral portion of the table 2. The depth of this step 2c is determined by the thickness of the springer 11 (drainage member), which will be described later, and the thickness of the bolt 2d for attaching the springer 11 and the table 2 to the table base 3. The total height of the head portion is determined to be below the upper surface position of the first table portion 2a.

As shown in FIG. 7 , a plurality of bolts 2d (12 in the example shown) are arranged at a predetermined distance from each other on the same radius of the peripheral portion of the table 2. As shown in FIG. 6 , these plurality of bolts 2d removably fasten the peripheral portion of the table 2 to the peripheral portion of the table base 3 via the springer 11. That is, by removing these bolts 2d, the table 2 and the springer 11 can be separated from the table base 3.

The upper end of the shaft 9 passing through the hollow motor rotation shaft 7a of the motor 7 is connected to the center of the lower surface of the polishing table 1. The lower end of the shaft 9 is connected to the rotary joint rotation shaft 9d of the rotary joint 9a via a heat medium flange 9k fixed to the lower end of the motor rotation shaft 7a. Therefore, the shaft 9 above the rotary joint 9a can rotate together with the table 2. The rotary joint 9a is connected to a heat medium supply pipe 9b that supplies heat medium to the shaft 9 side and a heat medium return pipe 9c that returns the heat medium discharged from the shaft 9 side. It is done.

Additionally, the shaft 9 contains pipes as shown in FIG. 8. The pipe 9f is arranged concentrically with the central axis L. On both sides of this pipe 9f, there is a pipe 9g for supplying the heat medium supplied from the heat medium supply pipe 9b of the rotary joint 9a to the heat medium flow path 4 in the table 2, and a heat medium A pipe 9h (located on the back side in FIG. 8) is additionally provided to discharge the heat medium discharged from the flow path 4 to the heat medium return pipe 9c of the rotary joint 9a.

The upper portions (head portion 9j) of the pipe 9f and conduits 9g and 9h are connected (inserted) to the bush 3d provided on the bottom surface side of the table base 3. This head portion 9j is formed of a two-stage cylinder with a small diameter at the top and a large diameter at the bottom, and has O-rings at two places above and below the circumferential surface of the small diameter cylinder and at one point below the circumferential surface of the large diameter cylinder (FIG. 8 (see thick line in) is provided, so that the heat medium from the pipe 9g is supplied to the heat medium flow path 4 through a passage not shown in the small diameter cylinder, and the heat medium is discharged from the heat medium flow path 4. It is configured to be discharged from the large-diameter cylinder to the pipe 9h through a passage not shown.

On the other hand, the lower portions of the pipe 9f and the conduits 9g and 9h are supported by the heat medium flange 9k. This heat medium flange 9k is fixed to the lower end of the motor rotation shaft 7a and is connected to the rotary joint rotation shaft 9d of the rotary joint 9a. Therefore, when a thermal medium is supplied to the thermal medium supply pipe 9b of the rotary joint 9a, the supplied thermal medium flows through the small diameter cylinder of the thermal medium flange 9k, the pipe 9g, and the head portion 9j. It passes through the heat medium flow path 4 in the table 2, through the large-diameter cylinder of the head 9j, the pipe 9h, and the heat medium flange 9k, and then again through the heat medium return pipe of the rotary joint 9a ( You can return to 9c).

The temperature adjustment of the table 2 is, for example, to raise the temperature of the table 2 when the temperature of the table 2 has not yet reached a predetermined temperature at the start of operation of the polishing machine. That is, a heating medium can be supplied to heat the table 2. Then, when the operation of the polishing device progresses and the temperature of the table 2 exceeds a predetermined temperature due to frictional heat accompanying polishing, a heat medium may be supplied to cool the table 2. In this way, by adjusting the table 2 to a constant temperature at all times, substrate polishing with high yield can be performed.

The flange 6 is provided with a branch pipe 9i. This branch pipe 9i is used for piping the power line or signal conductor of the wafer film thickness detector 5. These wirings are guided to the rotary joint 9a side via the pipe 9f. For this reason, although not shown, a rotary connector mechanism is also mounted on the lower part of the rotary joint 9a, and is configured to enable power supply and extraction of detection signals.

In this embodiment, the springer 11 shown in FIG. 6 is provided at the step 2c of the table 2, as described above, and its overall shape is the entire side surface of the table 2, and , It is formed into a cylindrical shape that can cover the dividing surface D between the table 2 and the table base 3 from the radial direction. The longitudinal cross-sectional shape of the springer 11 is an L-shaped top and bottom, and the upper curved portion of the shape is mounted on the step 2c of the table 2. In addition, the length of the part vertically descending from the curved part is determined to extend downward from the lower end of the draining projection 3a provided on the table base 3.

In this way, according to the present embodiment described above, the substrate is pressed against the upper surface and the polishing table 1 has a polishing table 1 that rotates around the central axis L, and the polishing table 1 forms the upper surface, and has a polishing table 1 inside. It has a table (2) having a heat medium flow path (4), and a table base (3) that supports the table (2) in a detachable manner. According to this configuration, only the table 2 having the heat medium flow path 4 can be partially replaced depending on the purpose of temperature control, so the specifications of the polishing table 1 can be changed at low cost.

For example, the table 2 is made of a material that has better workability than the table base 3 (e.g., when the table base 3 is stainless steel, the table 2 has better workability than stainless steel, aluminum, ceramic, etc.) It is also possible to form . In addition, it becomes possible to respond to replacement of the table 2 based on deterioration of the surface of the table 2 due to long-term use (for example, occurrence of rust when the material is aluminum).

In addition, in this embodiment, as shown in FIGS. 6 and 7, a plurality of bolts 2d for removably fixing the peripheral portion of the table 2 to the peripheral portion of the table base 3, and a plurality of bolts 2d ), since there is one or more knock pins 3b that position the table 2 relative to the table base 3 on the radial inner side, when the bolt 2d is removed, the table base 3 ) can be easily separated from the table (2) together with the springer (11). In addition, during installation, the position of the table 2 with respect to the table base 3 is determined via not only the plurality of bolts 2d but also one or more knock pins 3b arranged on the radial inner side thereof. Therefore, even if a split structure of the table 2 and the table base 3 is adopted, they can be rotated like an integrated structure.

In addition, in this embodiment, there is a cylindrical springer 11 that covers the dividing surface D between the table 2 and the table base 3 from the radial direction, and the springer 11 includes a plurality of bolts. Since it is detachably mounted on the periphery of the polishing table 1 at (2d), it is possible to prevent liquid from entering the dividing surface D between the table 2 and the table base 3.

Additionally, a cylindrical flange 6 that is rotationally driven by a motor 7 is connected to the lower surface of the table base 3, and the flange 6 is connected to the lower surface of the table base 3. A space is formed for mounting a wafer film thickness detector 5 that measures thickness. Since an annular drainage protrusion 3a protruding downward is formed on the lower surface side of the periphery of the table base 3, the wafer film thickness is caused by the inflow of liquid into the lower surface side of the table base 3. It is possible to prevent water leakage into the detector (5).

(Substrate processing device)

The substrate processing apparatus uses the substrate processing apparatus 100 of the first embodiment.

Even in the substrate processing apparatus 100 having the above configuration, polishing is performed for the purpose of temperature control by applying the polishing table 1 of the present invention to the polishing table 123 of the polishing unit 121 (polishing device). The specifications of the table 123 can be changed inexpensively.

(Attached structure of polishing pad)

Next, the attachment structure of the polishing pad 122 provided to be attached to the polishing table 123 having the above configuration will be described.

FIG. 9 is a schematic perspective view showing the overall configuration of the polishing unit 121 shown in FIG. 5.

As shown in FIG. 9, the polishing unit 121 includes a polishing table 123 and a top ring 124 that holds the substrate W, which is the polishing object, and presses it against the polishing pad 122 on the polishing table 123. It is available. The polishing table 123 is connected to a hollow table shaft 200 (flange 6 shown in FIG. 6 described above). The table axis 200 is connected to a polishing table rotation motor (motor 7 shown in FIG. 6 (not shown in FIG. 9) described above), and the polishing table 123 is integrated with the table axis 200. It is capable of rotation. In addition, the polishing table 123 shown in FIG. 9 is premised on the structure of the polishing table 1 (divided structure (laminated structure) of the table 2) described above, but the attachment structure of the polishing pad 122 is also applicable to a conventional polishing table (integrated structure (single-layer structure) of the table 2).

A polishing pad 122 is attached to the upper surface of the polishing table 123, and the surface of the polishing pad 122 constitutes a polishing surface for polishing the substrate W. The polishing pad 122 can be roughly divided into three types: hard foam type, non-woven type, and suede type.

The hard foam type is a pad containing pores, and is generally made of polyurethane. The non-woven fabric type is a non-woven fabric such as polyester impregnated with urethane or the like. The suede type is coated on a base material by wet molding, and the base material includes a product using the same non-woven fabric used in the non-woven pad above and a product using PET (polyethylene terephthalate). there is. These substrates are manufactured by coating a DMF (dimethylformamide) solution of urethane resin and substituting DMF with a coagulant (water), and pores are exposed on the surface.

A polishing liquid supply nozzle 125 is installed above the polishing table 123. The polishing liquid supply nozzle 125 supplies polishing liquid (slurry) to the polishing pad 122 on the polishing table 123. It is intended to be supplied. Inside the polishing table 123, a flow path for a heat exchange medium (heating medium flow path 4 shown in FIG. 6 (not shown in FIG. 9) described above) is provided.

By flowing cooling water as a heat exchange medium in the flow path for this heat exchange medium, heat exchange is performed between the heat exchange medium and the polishing table 123, and thermal deformation of the polishing table 123 due to frictional heat during polishing is prevented and polishing is performed. The surface temperature of the table 123 is controlled. Therefore, as shown in FIG. 9, a rotary joint 9a is provided at the lower end of the table axis 200, and coolant flows from the outside to the polishing table (not shown) via a coolant pipe (not shown) and the rotary joint 9a. 123) is intended to be supplied to the flow path.

The top ring 124 is connected to the top ring shaft 201, and the top ring shaft 201 moves up and down with respect to the support arm 202. By moving the top ring shaft 201 up and down, the entire top ring 124 is moved up and down with respect to the support arm 202 to determine its position. The top ring shaft 201 is rotated by driving a top ring rotation motor (not shown). As the top ring shaft 201 rotates, the top ring 124 rotates around the top ring shaft 201.

The top ring 124 is configured to hold the substrate W on its lower surface. The support arm 202 is configured to be rotatable around the shaft 203, and is positioned at the substrate transfer positions (the second transfer position TP2, the third transfer position TP3, and the sixth transfer position shown in FIG. 5 ). (TP6), the substrate W transported to the seventh transport position (TP7) is vacuum-sucked. The top ring 124 holding the substrate W on its lower surface can be moved upwards of the polishing table 123 by rotating the support arm 202.

The top ring 124 holds the substrate W on its lower surface and presses the substrate W against the surface of the polishing pad 122 . At this time, the polishing table 123 and the top ring 124 are each rotated, and the polishing liquid (slurry) is supplied onto the polishing pad 122 from the polishing liquid supply nozzle 125 provided above the polishing table 123. . A polishing liquid containing silica (SiO ₂ ) or ceria (CeO ₂ ) as abrasive grains can be used. In this way, while supplying the polishing liquid onto the polishing pad 122, the substrate W is pressed against the polishing pad 122 by the top ring 124 to move the substrate W and the polishing pad 122 relative to each other. (W) is polished. Additionally, during polishing, there may be relative movement (for example, oscillation (rotation)) other than rotation of the substrate W and the polishing pad 122. Thereby, deterioration of the same portion of the polishing pad 122 is prevented.

However, as shown in FIG. 10 described later, the polishing pad 122 is adhered to the table 2 via an adhesive layer 211. When polishing a large number of samples (substrates W), the polishing pad 122 experiences a decrease in polishing performance, an uneven polishing surface, and accumulation of foreign substances. Therefore, the polishing pad 122 is polished regularly or according to the number of polishes. ) needs to be newly added. At that time, if the adhesion of the polishing pad 122 is strong, a great deal of effort and time are required for new attachment work. For this reason, the polishing table 123 of this embodiment is provided with a structure for attaching the polishing pad 122 as shown in FIG. 10 .

Fig. 10 is a cross-sectional view showing the attachment structure of the polishing pad 122 according to one embodiment.

As shown in FIG. 10 , a coating layer 210 to which the polishing pad 122 is peelably adhered is formed on the upper surface of the table 2 forming the polishing table 123. An adhesive layer 211 is formed on the back surface 122b of the polishing pad 122 opposite the polishing surface 122a. In other words, the coating layer 210 is interposed between the table 2 and the polishing pad 122, and the adhesive layer 211 is interposed between the coating layer 210 and the polishing pad 122.

That is, the adhesive layer 211 may be formed on the upper surface of the coating layer 210. In addition, the “adhesion” of the adhesive layer 211 herein includes “adhesion.”

The adhesive forming the adhesive layer 211 is not particularly limited and includes pressure-sensitive adhesives, hot-melt adhesives, etc., with hot-melt adhesives being preferred. Adhesives may be used individually, or two or more types may be mixed. The hot melt adhesive is not particularly limited, and known ones can be used without particular restrictions. In addition to hot melt adhesives and pressure-sensitive adhesives, two-component curing type epoxy-based adhesives, silicone-based adhesives, etc. may be used instead of or in combination with hot melt adhesives and pressure-sensitive adhesives. Additionally, in addition to pressure-sensitive adhesives and hot melt adhesives, acrylic adhesives, silicone-based adhesives, and double-sided tapes may be used.

The material forming the table 2 may be the above-mentioned metal (aluminum (alloy), stainless steel), ceramic, or synthetic resin. Additionally, the surface of the aluminum (alloy) table 2 may be covered with an aluminum oxide or nickel film. The surface hardness of the table 2 can be increased by the aluminum oxide and nickel films. Additionally, when the table 2 is made of aluminum (alloy), if there is a heat medium flow path 4 or other mechanism (temperature control device, etc.) for temperature control within the table 2, aluminum (alloy) has good thermal conductivity. Therefore, it has good temperature control and can contribute to stabilizing polishing performance. Additionally, a flow path for discharging the slurry may be formed on the upper surface of the table 2.

The coating layer 210 is made of a low-adhesion material to enable the polishing pad 122 to be reattached with light effort in order to easily, efficiently, and safely perform the reattachment operation of the polishing pad 122. It is formed. In addition, the “low adhesion” of the low-adhesion material as used herein means “facilitating peeling of the polishing pad 122” and does not mean whether the adhesion is high or low for a specific material. In addition, the coating layer 210 also has the function of maintaining a good attached condition of the polishing pad 122 by preventing contact between the above-described oxide film and the polishing liquid, etc. and preventing corrosion of the table 2.

As the low-adhesion material forming the coating layer 210, fluororesin (PTFE (polytetrafluoroethylene), PCTFE (polychlorotrifluoroethylene), PVDF (polyvinylidene fluoride), FEP (tetrafluoroethylene·6 Propylene fluoride copolymer) and PFA (perfluoroalkoxyfluorine resin) are preferred. Additionally, depending on the polishing conditions (polishing liquid, type of polishing pad, etc.), polyamide resin, phenol resin, or polyester resin may be used. Examples of coating means for the coating layer 210 include electrostatic spray, hot melt spray, and cementing.

The thickness of the coating layer 210 is preferably, for example, 100 μm or less. In addition, in consideration of the adhesion of the coating material and the peeling characteristics of the adhesive available for the material, it is desirable to control the surface roughness of the coating layer 210 and ensure sufficient adhesion or adhesion to the polishing pad 122. Additionally, the coating layer 210 may have not only one layer but also multiple layers, such as second or third layers. According to such a coating layer 210 (fluororesin coating layer), the polishing pad 122 can be easily removed from the upper surface of the table 2 because the surface friction coefficient is low. For this reason, replacement of the polishing pad 122 can be performed more safely, quickly, and easily.

Additionally, the coating layer 210 may be a glass coating layer, a ceramic coating layer, or a diamond coating layer. Since this coating layer 210 has a harder surface and less deformation than the resin coating layer such as the fluororesin coating layer described above, the polishing pad 122 can be easily removed and the residual adhesive can also be easily removed. In addition, since the surface is harder than the resin coating layer and the deformation is small, the lifespan of the table 2 can be increased when the polishing pad 122 is reapplied multiple times.

In addition, in the case of a resin coating layer, maintenance of the coating surface (top surface of table 2) involves work of removing and recoating (attaching) the coating layer, but maintenance by minor polishing of the coating surface is required on a regular basis. Just by doing this, the flatness and cleanliness of the coating surface can be ensured and the lifespan of the table 2 can be increased. The polishing method for maintaining the coated surface can be performed by attaching a polishing member dedicated to polishing the coated surface to the dresser 126 (see FIG. 5) of the polishing unit 121 without bringing in a separate polishing device.

In this way, according to the present embodiment described above, a polishing device for flattening the substrate W includes a polishing pad 122 having a polishing surface 122a, and holding the substrate W on the polishing surface 122a ( The top ring 124 for pressing) and the moving device (top ring rotation motor, support) for moving (relatively moving) the table 2 (polishing table 123) and the top ring 124 to each other in order to polish the substrate W. It includes a table 2 having an arm 202, etc.) and a first surface (upper surface) for adhesion of the polishing pad 122, and the table 2 has a coating layer 210 of a low-adhesion material on the upper surface. ), the work of reattaching the polishing pad 122 can be performed simply, efficiently, and safely with light effort.

As described above, the present invention polishes various samples (substrates W) held on the top ring 124 while moving them relative to the polishing pad 122 using a polishing liquid suitable for each sample. In the polishing device, the lifespan of the polishing table 123 and the polishing pad 122 is increased. In order to improve its lifespan, the polishing performance of the table 2 is also taken into consideration, and a polishing table 1 (see FIG. 6) having an exchangeable upper surface of the present invention is provided, that is, a split structure of the table 2. Just do it. In addition, the division structure of the table 2 has a structure that actively discharges the used polishing liquid from the polishing table 1 and an outer peripheral portion of the polishing table 1 that prevents material deterioration or mixing of the polishing liquid due to the polishing liquid. The mounting structure (see FIGS. 6 and 4) can prevent the polishing liquid from entering the dividing surface D. Additionally, when using the polishing pad 122, it is necessary to satisfy both conflicting points: maintenance of its function (adhesion) and ease of replacement (removability). In consideration of the resistance of the polishing pad 122 and the table 2 below it to the polishing liquid, a coating layer 210 is provided as shown in FIG. 10, and in particular fluororesin, glass, ceramic, and diamond. It is desirable to do so.

Although preferred embodiments of the present invention have been described and explained above, it should be understood that these are exemplary and should not be considered limiting of the present invention. Additions, omissions, substitutions and other changes can be made without departing from the scope of the present invention. Accordingly, the present invention should not be considered limited by the foregoing description, but is limited by the scope of the claims.

For example, in the above embodiment, a configuration in which the polishing device of the present invention is applied to the polishing unit 120 of the substrate processing device 100 (chemical mechanical polishing (CMP) device) is illustrated. However, for example, the present invention It can also be applied to substrate processing equipment other than CMP equipment (for example, back surface polishing equipment, bevel polishing equipment, etching equipment, or plating equipment).

Claims (17)

A polishing table to which liquid is supplied to the upper surface and rotates around a central axis;
a ring-shaped liquid receiving member disposed below a peripheral portion of the polishing table;
a cylindrical drain member mounted on the periphery of the polishing table and having a lower end extending toward the liquid receiving member;
a cover member disposed radially outward from the drain member and whose radial gap with the drain member gradually decreases toward the upper surface of the polishing table;
It further has a gas-liquid separation device that sucks gas through the liquid receiving member and separates the liquid contained in the gas,
The suction path of the gas-liquid separation device is a gap formed between the drain member and the cover member,
The cover member is disposed with a gap from the outer peripheral wall of the liquid receiving member,
A polishing device wherein a gap size between the cover member and the outer peripheral wall is smaller than a gap size between the cover member and an upper end of the drain member. According to claim 1,
The liquid receiving member has an inner peripheral wall disposed radially inside the lower end of the drain member,
The polishing apparatus, wherein the lower end of the drain member extends downward than the upper end of the inner peripheral wall. According to claim 1,
A step for mounting the drain member is formed on the periphery of the polishing table,
The drain member is mounted on the bottom surface of the step via a bolt,
a first seal member that seals a gap in a radial direction between the drain member and a side surface of the step;
A polishing device comprising a second sealing member that seals an insertion hole of the drainage member through which the bolt is inserted. According to claim 1,
A polishing device wherein the cover is movable in an up and down direction. a polishing unit that polishes the substrate;
A substrate processing device having a cleaning unit for cleaning the substrate polished in the polishing unit,
A substrate processing apparatus, wherein the polishing unit includes the polishing device according to any one of claims 1 to 4. delete delete delete delete delete delete delete delete delete delete delete delete