JP2001198801A - Polishing device and polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing device and a polishing method suitable for flattening the surface of the work to be processed at a controlled temperature by a chemical and mechanical polishing(CMP) method. SOLUTION: A fluid pressure in a first passage 13 to supply the fluid 11 to a space 14 is kept bigger than a fluid pressure in a second passage 15 to discharge the fluid from the space 14 by using a polishing tool 100 having the space 14 formed so as to make contact with a polishing pad 1 through an elastic body 2 in a polishing pad holder 5. The flow of the fluid is produced in the space 14 and the fluid pressure in the space 14 is practically kept at a designated value by supplying the fluid to the space 14 and discharging it from the space 14. The polishing pad 1 is pressed onto a work by transmitting the fluid pressure in the space 14 to the polishing pad 1 through the elastic body 2, and the polishing pad 1 is moved relatively to the work while controlling the temperature of the fluid supplied to the space 14, in order to grind the work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus and a polishing method suitable for flattening a work surface of a work (workpiece) by polishing, and more particularly to a polishing method for forming a wiring on a semiconductor substrate. The present invention relates to a polishing apparatus and a polishing method suitable for flattening an insulating material layer formed on a formation surface or a wiring by a chemical mechanical polishing method at a controlled temperature.

[0002]

2. Description of the Related Art In recent years, processing methods for flattening a work surface of a work by polishing have been applied in various fields. As an example, a flattening process in a wiring process of a semiconductor wafer can be cited.

The wiring process of a semiconductor wafer is performed, for example, as follows. That is, when a wiring made of a conductive material such as Al, W, and Cu is formed on a semiconductor wafer, and then an insulating material such as SiO ₂ is laminated,
Polishing and planarization of an insulating material is necessary to secure a depth of focus in a photolithography step of a multilayer wiring process. Also, a groove is provided in the semiconductor substrate, a film of a conductive material is formed so that the conductive material is embedded in the groove, and then, in order to ensure insulation of the conductive material in an adjacent groove, the groove is formed in the groove. It is necessary to planarize so that the top surface of a certain conductive material is flush with the top surface of the substrate.

[0004] When the above-mentioned flattening process is performed, chemical mechanical polishing (Chemical Mechanical Polishing) is performed.
g; sometimes abbreviated as CMP). The CMP method is polishing performed by utilizing the fact that a polishing liquid chemically reacts with a work on a surface to be processed. Therefore, in order to perform polishing at a uniform polishing rate so as to achieve good processing accuracy, it is necessary to stably advance a chemical reaction between the polishing liquid and the work.

The processing accuracy corresponds to the degree of uniformity of an actual processing amount with respect to a target processing amount (generally represented by the thickness of a removed workpiece in polishing). It can be represented by a difference in thickness between a portion having the largest thickness and a portion having the smallest thickness in a later work. Therefore, when the target processing amount is the same, the processing accuracy becomes worse as the thickness difference increases.

[0006]

One of the factors affecting the chemical reaction between the polishing liquid and the workpiece is temperature. For example, if the temperature of the polishing liquid on the surface to be processed, the work and the polishing pad are too low, the reaction does not proceed smoothly,
The polishing (processing) rate may decrease. On the other hand, when the temperature of the polishing liquid increases due to frictional heat generated during polishing, abrasive grains (eg, silica and alumina) contained in the polishing liquid aggregate due to vaporization of the polishing liquid, and the aggregated abrasive grains cause the surface to be processed. Scratches may occur. This aggregation is remarkably recognized when the temperature of the polishing liquid is 80 ° C. or higher. As described above, in the CMP method, the temperature of the polishing liquid, the work and the polishing pad near the surface to be processed affects not only the polishing efficiency but also the quality of the work after polishing.

Further, it has been found that when the polishing surface of the polishing pad is exposed to high temperatures, its life is shortened. For example,
In the case where the polishing pad is made of foamed polyurethane, if the temperature exceeds 70 ° C., deterioration starts, and air bubbles are crushed in the surface layer. Depending on such a polishing pad, it is difficult to proceed with polishing, and replacement is often required. Similarly, a retainer ring made of POM (polyoxymethylene) provided around the work is easily deformed or deteriorated at a high temperature.

Therefore, if the temperature of the polishing liquid, the work and the polishing pad near the surface to be processed can be controlled, the polishing (chemical reaction) can proceed under optimum conditions, the quality of the work after polishing can be improved, and the polishing can be performed. It is believed that the polishing pad and retainer ring of the device can be used for an extended period of time. Therefore, it has been attempted to perform polishing by the CMP method with some kind of temperature control.

For example, in Japanese Patent Application Laid-Open No. 9-55361, in order to control the temperature of the surface of a semiconductor wafer during polishing so as to be uniform in the surface of the semiconductor wafer,
A semiconductor manufacturing apparatus in which a semiconductor substrate holding mechanism includes a plurality of temperature control elements is disclosed. Similarly, JP-A-8-216
No. 023 and JP-A-8-25214 also disclose controlling the temperature of the work. Japanese Patent Application Laid-Open No. 7-221054 describes that the temperature of the polishing pad on the sliding contact surface is raised by heating the surface plate, and Japanese Patent Application Laid-Open No. 8-243915 describes that the temperature of the polishing liquid is controlled. ing.

[0010] In any of these, a polishing apparatus for performing polishing by pressing a work such as a semiconductor wafer against a polishing cloth or a polishing pad attached to a surface plate and moving the polishing cloth or the polishing pad relative to the work. Or, it relates to a polishing method. The polishing cloth or polishing pad used in such a polishing apparatus or the like generally has a diameter larger than 600 mm. It is difficult to attach such a large polishing cloth to the surface plate without causing air bubbles between the surface and the surface plate and without causing wrinkles on the polishing cloth or the like. That is, as the diameter of the platen is larger, the skill of attaching the polishing cloth or the like is required to be more skilled, and this has been one factor that lowers the efficiency of the entire polishing process.

In general, a semiconductor wafer has undulations having a period of several cm and an amplitude of several μm on its surface due to a large number of materials stacked on a silicon substrate.
When polishing a semiconductor wafer, it is necessary to flatten only fine irregularities existing on the surface to be processed by polishing while leaving the undulations caused by the undulations as they are. For that purpose, it is desirable to carry out polishing so that the polishing pad follows the undulation.

The present applicant has disclosed a polishing apparatus in which the operation of attaching a polishing pad is easy, and the polishing pad has improved followability of undulation of a work, as disclosed in Japanese Patent Application Laid-Open No. 7-2017.
No. 88 proposes this. FIG. 4 shows a schematic sectional view of the device. In the apparatus, the polishing pad (401) is attached to the elastic body (402), and a space (403) capable of storing a pressurized fluid is formed in the polishing tool. The fluid pressure is applied to the polishing pad (4) through the elastic body (402).
01), whereby the polishing pad (401) is pressed to follow the undulation of the work (404). As a result, the work surface of the work (404) can be polished at a uniform polishing rate. Polishing is performed by rotating the polishing pad (401) and the work (404) while the polishing pad (401) is pressed against the work (404). According to the device, the diameter is 300mm
A polishing pad of a small diameter can be used.

The present invention relates to the above apparatus and method for polishing a work by using a small-diameter polishing pad, pressing the polishing pad against the work with a pressurized fluid, and moving the polishing pad relative to the work. It is another object of the present invention to control a polishing pad and / or a work near a surface to be processed to a predetermined temperature.

[0014]

According to the present invention, there is provided a polishing apparatus comprising a system for controlling a temperature of a polishing pad, the system comprising: 1) a polishing pad; Including an elastic body attached to the surface opposite to the polishing surface, and a polishing pad holder,
The polishing pad holder has a shaft portion extending perpendicular to the polishing surface of the polishing pad, and a polishing tool in which a space is formed in the polishing pad holder so as to contact the polishing pad via an elastic body. 2) a first path for supplying a fluid to the space, a first path partially passing through a shaft of a polishing pad holder; 3) a second path for discharging a fluid from the space. A second path partially passing through the shaft of the polishing pad holder; 4) means for controlling the temperature of the fluid supplied to the space;
And 5) A first polishing apparatus comprising means for controlling the pressure of the fluid in the space.

The first polishing apparatus includes a space formed in the polishing pad holder of the polishing tool so as to be in contact with the polishing pad via an elastic body (this space is referred to as a “space in the polishing pad holder” or simply a “space”). (Also referred to as), while the fluid is supplied to the space substantially continuously via the first path and discharged from the space via the second path. Generates a flow of fluid in the space, thereby allowing a continuous heat exchange between the fluid and the polishing pad. Therefore, during the polishing, if the temperature of the fluid is controlled and the fluid at the controlled temperature is supplied into the space, the polishing pad can be controlled to a predetermined temperature by heat exchange with the fluid, and as a result, during polishing, It is possible to control the temperature near the surface to be processed.
In this specification, “fluid” means a gas or a liquid having fluidity.

Specifically, the flow of the fluid in the space can be caused by supplying the fluid to the space via the first path and discharging the fluid from the space via the second path. At this time, the pressure of the fluid in the second path is lower than the pressure of the fluid in the first path. Accordingly, the pressure of the fluid in the space is equal to the pressure of the fluid in the first path and the second pressure.
And the pressure of the fluid in the path. Therefore, in the present invention, "the pressure in the space is substantially maintained at a predetermined value"
The term is used to mean that the pressure of the fluid in the space is maintained at a constant value while generating the flow of the fluid. The pressure of the fluid in the space is transmitted to the polishing pad via the elastic body, thereby ensuring that the polishing pad is pressed against the work. Alternatively, by controlling both the pressure of the fluid to be supplied and the pressure of the fluid to be discharged to predetermined values, the pressure of the fluid in the space can be more accurately maintained at the predetermined value.

The pressure of the fluid in the space may be changed for some reason, for example, by a large external force acting on the polishing pad to deform the space, thereby temporarily increasing or decreasing the pressure of the fluid in the space. In such a case, the pressure of the fluid supplied to the first path is reduced or increased, or the flow rate of the fluid discharged from the second path is increased or decreased instantaneously. The pressure can be returned to the predetermined pressure in a short time. The above-mentioned "keeping the pressure in the space" substantially "at a predetermined value" means that when a pressure change occurs in the fluid in the space in such a short time, such a pressure change is generated for a short time. This also includes aspects corrected by the above.

The present invention is also a polishing apparatus provided with a system for controlling the temperature of a work and a retainer ring, the system comprising: 1) a work fixing plate for supporting and fixing the work; 2) a work fixing plate. Attached work temperature control means and work temperature detector; 3) work temperature control means; 4) retainer ring temperature mounted so as to be located on the side of the retainer ring opposite to the polishing surface; A second polishing apparatus, comprising: an adjusting means and a retaining ring temperature detector; and 5) means for controlling the retaining ring temperature adjusting means.

The second polishing apparatus secures a good polishing rate by heating or cooling the work and the retainer ring to control the temperature thereof, and also prevents the temperature of the polishing liquid from rising to prevent the polishing liquid from rising. To prevent agglomeration of the abrasive grains. The temperature adjusting means is means for heating and / or cooling an object (here, the work and the retainer ring), and means an element whose operation can be controlled by a temperature control means described later. Means temperature information of the object, for example, the temperature of the object or a change in temperature over time is measured. The means for controlling the temperature control means includes controlling the operation of the temperature control means to set the temperature of the object to a predetermined temperature based on the temperature information from the temperature detector and the target temperature (set temperature). Means what you do.

The second polishing apparatus is characterized in that a work and a retainer ring are provided with independent temperature control means, a temperature detector and a means for controlling the temperature control means, respectively. This is because the material of the work surface of the workpiece (eg, SiO ₂ ) and the material of the retainer ring (eg, PO
Polyacetal resin such as M)
This is to cope with the fact that frictional heat generated during polishing is easily stored in the retainer ring. That is, in order to make the two have the same temperature, it is necessary to make the degrees of heating or cooling different from each other. Therefore, the temperature of the work and the retainer ring can be controlled independently.

The second polishing apparatus having the system for controlling the temperature of the workpiece and the retainer ring also has the temperature control system for the polishing pad included in the first polishing apparatus described above. In such a case, the temperature of the work surface of the workpiece can be controlled with higher accuracy.

The present invention also provides a method of polishing a work by moving a polishing pad relative to the work, the polishing pad comprising an elastic pad attached to a surface opposite to a polishing surface of the polishing pad. Body, and a polishing pad holder, the polishing pad holder having a shaft extending perpendicularly to the polishing surface of the polishing pad, and in the polishing pad holder, the polishing pad is in contact with the polishing pad via an elastic body. Using a polishing tool having a space formed therein, maintaining the pressure of the fluid in the path for supplying the fluid to the space greater than the pressure of the fluid in the path for discharging the fluid from the space, and transferring the fluid to the space. Supplying and discharging the fluid from the space causes a flow of the fluid in the space, and maintains the pressure of the fluid in the space substantially at a predetermined value. By transmitting the pressure of the fluid to the polishing pad via the elastic body, the polishing pad is pressed against the work, the temperature of the fluid supplied to the space is controlled to a temperature within a predetermined range, and the A first polishing method characterized by causing heat exchange is provided.

This method can be carried out, for example, using the first polishing apparatus. By controlling the temperature of the fluid supplied to the space to a temperature within a predetermined range, it becomes possible to advance polishing accompanied by a chemical reaction at a good processing rate, and to prevent the temperature of the polishing liquid from rising, This prevents abrasive grains contained in the polishing liquid from agglomerating.

Further, according to the present invention, in a method of polishing a work by moving a polishing pad relative to the work, the temperature of the work supported on the work fixing plate is adjusted to the opposite side of the work surface of the work. The temperature of the retainer ring provided around the work is controlled by controlling the work temperature adjusting means located on the side of the surface of the work so that the temperature is within a predetermined range. The second polishing method is characterized in that the temperature is controlled within a predetermined range by controlling the retainer ring temperature adjusting means located on the side of the second polishing method.

This polishing method can be carried out, for example, by the above-mentioned second polishing apparatus. The temperature of the work and the retainer ring can be appropriately set according to the type of the work and the polishing liquid. It is not necessary to control the temperature of the work and the retainer ring so as to be the same temperature. For example, the work may be heated and the retainer ring may be cooled.

The first polishing method and the second polishing method can be combined. In that case, the temperatures of the fluid, the work, and the retainer ring supplied to the space in the polishing pad holder may be set to different temperatures. The three independent temperature controls allow the polishing of the workpiece to proceed more advantageously.

Further, in the polishing method of the present invention, a polishing liquid having a temperature and / or a flow rate within a predetermined range may be supplied. By controlling the temperature and / or the flow rate of the polishing liquid, the polishing rate and the like can be controlled more accurately, and the quality of the polished work can be further improved.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the apparatus and method of the present invention will be described. First, a first polishing apparatus of the present invention and a polishing method of the present invention performed by the polishing apparatus will be described. A first polishing apparatus of the present invention is a polishing apparatus including a system for controlling a temperature of a polishing pad, the system comprising: 1) a polishing pad, and affixing to a surface of the polishing pad opposite to a polishing surface. Including elastic body, and polishing pad holder,
The polishing pad holder has a shaft portion extending perpendicular to the polishing surface of the polishing pad, and a polishing tool in which a space is formed in the polishing pad holder so as to contact the polishing pad via an elastic body. 2) a first path for supplying a fluid to the space, a first path partially passing through a shaft of a polishing pad holder; 3) a second path for discharging a fluid from the space. A second path partially passing through the shaft of the polishing pad holder; 4) means for controlling the temperature of the fluid supplied to the space;
And 5) means for controlling the pressure of the fluid in the space.

The polishing tool used in the first polishing apparatus of the present invention has a shaft portion extending perpendicular to the polishing surface of the polishing pad, and is in contact with the polishing pad via an elastic body inside. Has a polishing pad holder in which a space is formed. The space in the polishing pad holder is for containing a fluid with controlled pressure. One surface of the space is defined by an elastic body in which a polishing pad is attached to a surface facing the work, so that the pressure of a fluid existing in the space can be transmitted to the polishing pad via the elastic body. Secured.

The elastic body is preferably formed of a thin stainless plate diaphragm, for example. The polishing pad is
An appropriate material can be selected according to the type of the work. For example, when polishing a film made of SiO ₂ formed on a semiconductor wafer, foamed polyurethane is preferable. The shape and size of the polishing pad can be determined according to the shape and size of the work, for example, 4 to 12 inches in diameter (about 100 to
When polishing a substantially circular semiconductor wafer (300 mm), a circular polishing pad having a diameter about 100 mm larger than the diameter of the semiconductor wafer may be used.

The polishing tool may have a polishing liquid supply path which penetrates the shaft of the polishing pad holder and discharges the polishing liquid from the center of the polishing pad. In this case, it is necessary to provide an opening at the center of the polishing pad and the elastic body so that the supply of the polishing liquid is ensured.

In the first polishing apparatus of the present invention, a part of the first path for supplying the fluid to the space and a part of the second path for discharging the fluid from the space penetrate the polishing tool. ing. Part of the first path and the second path preferably pass through the shank of the polishing pad holder. One end of the first path is connected to a supply source of fluid supplied to a space in the polishing pad holder, and the other end communicates with the space.
One end of the second path communicates with the space, and the other end communicates with the outside of the polishing apparatus to discharge fluid.

The fluid is supplied to the space via the first path. The pressure of the fluid in the first path is maintained at a predetermined value by a suitable pressure adjusting means capable of maintaining the pressure on the secondary side at a predetermined value. The pressure adjusting means includes, for example, a pressure adjusting valve, which is provided between the fluid supply source and the polishing tool.
It is good to intervene in the route.

In order to discharge the fluid through the second passage while maintaining the pressure of the fluid in the second passage at a predetermined value, a valve is provided in the second passage so that an unnecessarily large amount of fluid is supplied. It is preferable to prevent discharge. When the pressure of the fluid in the first path is maintained at a predetermined value by the pressure regulating valve, if the fluid is discharged from the second path at a constant flow rate, the pressure of the fluid in the second path is also approximately equal to the predetermined value. Will be maintained. As a valve for discharging the fluid in this way, there is a flow control valve such as a needle valve or a diaphragm valve. The flow control valve may be provided in the second path together with the pressure gauge as needed. The pressure gauge is used for initially setting the degree of opening and closing of the flow control valve according to the pressure in the second path. In this case, "means for controlling pressure"
Is constituted by a pressure adjusting means provided in the first path, preferably a pressure adjusting means provided in the first path and a flow rate adjusting valve provided in the second path.

The second path may be provided with a valve that opens fully when the pressure exceeds a predetermined pressure and completely closes when the pressure is less than the predetermined pressure, instead of the flow control valve as described above. In this case, the “means for controlling the pressure” is constituted by the pressure adjusting means provided in the first path and the valve.

Alternatively, instead of the flow control valve as described above, the flow rate of the fluid discharged from the second path is set in the second path so that the pressure in the second path becomes constant. A valve that can be changed at any time (for example, a valve using an electropneumatic regulator) may be provided in the second path. In that case,
The “means for controlling the pressure” includes pressure adjusting means provided on the first path and pressure adjusting means provided on the second path.

Since the pressure of the fluid in the second path is smaller than the pressure of the fluid in the first path, the fluid in the space flows through the space while providing the pressure required for the polishing pad to press against the work. pass. As described later, since the temperature of the supplied fluid is controlled, continuous predetermined heat exchange occurs between the fluid passing through the space and the work.

The fluid used in the present invention is preferably a gas such as air or nitrogen. Also, as long as it does not adversely affect the work and the polishing pad,
The fluid may be a liquid such as water.

In the present invention, the pressure of the fluid in the space is controlled to be higher than the pressure of the surrounding atmosphere of the polishing apparatus so that the polishing pad is pressed against the work. Specifically, the gauge pressure of the fluid in the first path is 19.6 to 49 kPa (0.2 to 0.5 kgf / cm ² ),
It is preferable to discharge the fluid by setting the pressure of the fluid in the second path to be lower than the pressure of the fluid in the first path by about 490 Pa (about 0.005 kgf / cm ² ). Therefore, the pressure of the fluid in the space takes a value between the pressure of the fluid in the first path and a pressure about 490 Pa (about 0.005 kgf / cm ² ) lower than that. In the present invention, the gauge pressure refers to a pressure based on a pressure outside a polishing apparatus, particularly a polishing pad. For example, if the polishing is performed at atmospheric pressure, the gauge pressure corresponds to the absolute pressure minus the atmospheric pressure.

The polishing pad is pressed against the work by the pressure of the fluid transmitted through the elastic body so as to follow the undulation of the work. As a result, it is possible to flatten only the fine irregularities existing on the surface to be processed by polishing while keeping the undulations caused by the undulation of the workpiece.

The fluid flowing in the space is supplied to the space in a temperature-controlled manner such that the polishing pad is maintained at a temperature within a predetermined range by continuous heat exchange occurring between the fluid and the polishing pad. Therefore, the first polishing apparatus of the present invention
Means is provided for controlling the temperature of the fluid supplied to the space. Such temperature control means are: 1) a temperature control means capable of heating and / or cooling the fluid and its operation is controllable; 2) a temperature detector for obtaining temperature information of the discharged fluid; And 3) preferably comprises control means for controlling the operation of the temperature adjusting means based on the temperature information obtained from the temperature detector and the target temperature. These may be electrically connected, for example, to form a closed loop control system.

[0042] The temperature adjusting means is provided in a first path between the polishing tool and the fluid supply source. The temperature control means may be any as long as it can heat and / or cool the fluid, and may be, for example, a heat exchanger. Further, in the present invention, the temperature of the fluid supplied to the space is preferably adjusted before adjusting the pressure of the fluid supplied to the space. Therefore, when the pressure adjusting means is provided in the first path, the temperature adjusting means:
It may be located between the fluid supply and the pressure regulating means.
That is, in the present invention, priority is given to setting the pressure of the fluid to be supplied to a predetermined value. Therefore, after adjusting the temperature, the temperature change that occurs when the pressure is further adjusted is ignored, or the change is taken into account. Preferably, the temperature of the fluid is adjusted.

The temperature detector can measure the temperature of the fluid discharged from the second path. The temperature detector may be, for example, a thermocouple or an infrared radiation thermometer.

The temperature control of the fluid is specifically performed as follows. For example, if the temperature inside the space becomes high for some reason and the temperature of the fluid detected by the temperature detector becomes high, the temperature of the polishing solution also increases, and there is a possibility that agglomeration of abrasive grains in the polishing solution may occur. For this reason, it is necessary to lower the temperature of the supplied fluid, and therefore, the means for controlling the temperature control means controls the temperature control means so that the supplied fluid is cooled. Conversely, if the temperature of the fluid detected by the temperature detector is low, which may cause the temperature of the polishing liquid to decrease and the polishing rate to decrease, a means for controlling the temperature adjusting means is provided. The temperature control means is controlled so that the fluid to be heated is heated. The control is performed by appropriate control means,
For example, it may be performed by a computer.

The temperature of the supplied fluid may be appropriately set according to the type of the polishing liquid, the type of the polishing pad and the work, and the polishing conditions (for example, the number of rotations of the polishing pad). For example, when an insulating film made of SiO ₂ or the like is formed on a semiconductor wafer, and the insulating film is polished with a polishing pad made of polyurethane foam using a polishing liquid in which SiO ₂ or the like is dispersed as abrasive grains in an aqueous ammonia solution. The temperature of the polishing pad is desirably maintained at 50 to 70 ° C. so that a good polishing rate can be secured and the agglomeration of abrasive grains in the polishing liquid can be prevented. It is preferable to control to ° C.

The work is polished by moving the polishing pad relative to the work. Therefore,
In the present invention, it is desirable that the polishing tool is configured to be rotatable about a central axis of a shaft portion of the polishing pad holder. In that case, it is preferable to connect the first and second paths to a rotary joint so that the fluid can be supplied through the first path and the fluid can be discharged through the second path even during rotation. .

FIG. 1 shows an example of the temperature control system of the polishing pad described above. The temperature control system includes a polishing tool (100), a first path (13), a second path (15), a pressure regulating valve (10) as fluid pressure control means,
It includes a flow control valve (16) and a pressure gauge (17), and a heat exchanger (12) as a means for controlling the temperature of the fluid.

The polishing tool (100) includes a polishing pad (1),
The polishing pad holder (5) includes an elastic body (2) and a polishing pad holder (5), and a space (14) is formed in the polishing pad holder (5).
Is provided with a polishing liquid supply path (8). The polishing liquid supply path (8) is connected to a polishing liquid supply source (7) so that the polishing liquid (6) is supplied from the center of the polishing pad (1). The polishing pad (1) has an opening at the center so that a polishing liquid can be supplied. The outer periphery of the opening is an inner peripheral mounting member (3), and the outer edge of the polishing pad is an outer peripheral mounting member (4). ) Is attached airtightly to the polishing pad holder (5).

The first path (13) and the second path (1) are provided on the shaft (5a) of the polishing pad holder of the polishing tool (100).
Part of 5) penetrates, and one end of each penetrates into the space (14) in the polishing pad holder. Route 1 (13)
Is connected to a fluid supply source (9), and a second path (15)
The other end communicates with the outside of the polishing tool as a fluid outlet.
In FIG. 1, in order to avoid complicating the drawing, the first path and the second path show only a portion located in the polishing tool, and the other portions include a fluid ( Only the flow of 11) is shown by arrows.

The fluid (11) supplied to the space (14) is heated or cooled to a predetermined temperature by the temperature control means (12) from the fluid supply source (9) and then sent to the pressure control valve (10). And a predetermined pressure there. The fluid (11) adjusted to a predetermined pressure is sent into the space (14) via the first path in the polishing tool (100), and further sent to the second path (15).
And is discharged from the flow control valve (16). In the embodiment shown, the second path (15) branches off, one leading to the flow regulating valve (16) and the other leading to the temperature detector (18). The flow rate adjusting valve (16) can change the flow rate by adjusting the opening / closing degree of the valve. The opening / closing degree of the flow control valve is the first
While observing the reading of the pressure gauge (17), the fluid is discharged from the flow control valve (16) while maintaining the fluid pressure in the second route at a predetermined value in relation to the pressure of the fluid in the route. Do. To generate a flow velocity in the space (14),
The pressure of the fluid in the second path, that is, the value indicated by the pressure gauge (17), must be smaller than the pressure of the fluid in the first path, that is, the pressure of the fluid at the outlet (secondary side) of the pressure regulating valve (10). The flow control valve must be adjusted to satisfy this condition.

The fluid sent to the temperature detector (18) is used for obtaining temperature information of the fluid to be discharged. The temperature information obtained by the temperature detector (18) is converted into, for example, an electric signal and sent to control means (19) for controlling the heat exchanger (12), and the control means (19) The heat exchanger (12) is controlled in order to make the temperature of the water suitable. Thus, in the illustrated embodiment, the temperature detector (18), the control means (19) and the heat exchanger (12) constitute a closed loop control system, and the temperature of the fluid (11) is reduced by the system. Controlled and stable.

In the illustrated embodiment, the polishing liquid is supplied from the center of the polishing pad. However, the polishing liquid may be dropped on a work, for example.
The polishing liquid supply path (8) shown in (1) becomes unnecessary, and there is no need to form an opening in the center of the polishing pad, and the polishing pad is held by the polishing pad holder exclusively at the outer edge.

The polishing liquid may be supplied to the work while controlling the temperature within a certain range. For example, in the embodiment shown in FIG. 1, a heat exchanger or the like may be connected to the polishing liquid supply source (7) to heat or cool the polishing liquid to a predetermined temperature.

The polishing liquid is preferably supplied to the work at a flow rate of about 100 cm ³ / min.

In order to control the pressure in the space with higher accuracy, pressure adjusting means is provided in both the first path and the second path so that the pressure of the fluid in each path becomes a predetermined value. Is preferred. Also in this case, the pressure of the fluid in the second path is smaller than the pressure of the fluid in the first path, and therefore, the pressure of the fluid in the space is equal to the pressure of the fluid in the first path and the pressure of the fluid in the second path. Between the values.

As the pressure adjusting means provided in the first path and the second path, for example, a valve combined with an electropneumatic regulator (or a solenoid valve) can be used. By arranging the electropneumatic regulator capable of pressure control in both the first and second paths, for example, the pressure of the fluid in the space due to an external factor can be reduced as compared with the case where the flow rate regulating valve is provided in the second path. When the pressure changes, the pressure can be quickly returned to the predetermined pressure, and the pressure of the fluid in the space can be controlled with better accuracy. According to the electropneumatic regulator, the pressure of the fluid to be supplied and the pressure of the fluid to be discharged can be changed as needed based on an external electric signal. Therefore, if the set pressure of one or both of the electropneumatic regulators is changed by an electric signal while polishing is being performed, the pressure of the fluid in the space in the polishing pad holder can be easily changed. Therefore, the polishing (processing) conditions can be easily changed from the outside.

For example, if the pressure of the fluid in the first path is 3
The first electropneumatic regulator provided in the first path is set to be 9.2 kPa (0.4 kgf / cm ² ), and the fluid pressure in the second path is 38.7 kPa (0.395 kgf / cm ² ). By setting the second electropneumatic regulator provided in the second path so that the pressure difference between the fluid in the first path and the fluid in the second path is about 500 Pa (about 0.005 kgf / cm ² ), Fluid pressure is 38.7-39.2 kP
a (0.395-0.4 kgf / cm ² ).
Further, the pressure of the fluid in the first path is 40.2 kPa.
(0.41 kgf / cm ² ) by setting the first electropneumatic regulator provided in the first path so that the fluid pressure in the second path is 39.2 kPa (0.40 kgf / cm ² ). By setting the second electropneumatic regulator provided in the second path,
The pressure difference between the fluid in the first path and the fluid in the second path is about 1 kPa (about 0.01 kgf / cm ² ), and the fluid moves in the space at twice the flow rate in the case exemplified above, and the polishing pad and the polishing pad The heat exchange during is further promoted. In this case, the pressure of the fluid in the space is 39.2 to 40.2 kPa (0.40 to 40 kPa).
0.41 kgf / cm ² ).

FIG. 2 shows an example of a temperature control system for a polishing pad using an electropneumatic regulator. The members or elements having the same reference numerals as those in FIG. 1 have the same functions as the corresponding members or elements in FIG. In FIG. 2, a first electropneumatic regulator (21) and a second electropneumatic regulator (23) are connected to the first path and the second path, respectively. Each of the electropneumatic regulators (21) and (23) is connected to the fluid supply source (9), and the pressure of the fluid of the fluid supply source (9) acts on the fluid in the first path and the second path. Pressure can be adjusted. The first and second electropneumatic regulators (21) and (23) are controlled by external signals (22) and (24) so that the pressures of the fluids in the first path and the second path become predetermined values. . Since the electropneumatic regulator is controlled by remote control, the pressure of the discharged fluid is displayed on the operation unit, and therefore, a pressure gauge corresponding to the pressure gauge (17) in FIG. 1 is not provided. Fluid (1
1) connects the second path (15) to the second electropneumatic regulator (2
It is discharged via the valve (23a) of 3).

Next, a second polishing apparatus of the present invention and a polishing method of the present invention performed by the polishing apparatus will be described. A second polishing apparatus according to the present invention includes a system for controlling the temperature of a work and a retainer ring. The system includes: 1) a work fixing plate for supporting and fixing the work; 2) a work attached to the work fixing plate. Temperature control means and work temperature detector; 3) means for controlling work temperature control means; 4) retainer ring temperature control means and retainer mounted so as to be located on the surface of the retainer ring opposite to the polishing surface. A ring temperature detector; and 5) means for controlling the retainer ring temperature adjusting means.

The work fixing plate supports and fixes the work so that the work does not deviate from a predetermined position during polishing.
It is preferable that the work fixing plate specifically includes a suction plate having an opening for vacuum suction and a space to be evacuated. Further, a work temperature adjusting means is attached to the work fixing plate, and the temperature of the work is adjusted by the work temperature adjusting means through the fixing plate, so that the work fixing plate is formed of a material having high thermal conductivity. More specifically, it is preferably made of Teflon-coated stainless steel or SiC.

It is desirable that the work temperature adjusting means and the work temperature detector attached to the work fixing plate so as to be located on the side opposite to the work surface of the work are located as close as possible to the work. It is more desirable to install it so that it contacts the work. If it is away from the work, it becomes difficult to efficiently heat or cool the work, and the temperature of the work cannot be detected correctly.

During polishing, the temperature of the work needs to be controlled to a temperature within a predetermined range according to the type of the polishing liquid and the work, the polishing conditions, and the like. For this purpose, the work needs to be heated or cooled. . The heating or cooling of the work is performed by the work temperature adjusting means. The work temperature adjusting means is preferably a thermoelectric heating element and / or a thermoelectric cooling element utilizing the Peltier effect. Such elements are small and easy to install,
For example, the work can be heated or cooled only by applying a current to the element by remote control, and thus is preferably used in the present invention.

At least one thermoelectric heating element and at least one thermoelectric cooling element are mounted on a work fixing plate. When heating is required, current is applied exclusively to the thermoelectric heating element, and when cooling is required, only thermoelectric cooling element is applied. The heating and cooling of the work may be freely performed by passing an electric current. Alternatively, in one element utilizing the Peltier effect, the direction of the current may be arbitrarily changed so that the element can function as both a heating element and a cooling element.

A plurality of work temperature adjusting means may be provided.
Further, the workpiece may be formed in a ring shape in order to uniformly heat the workpiece.

The work temperature detector may be any as long as it can measure the temperature near the work surface of the work, and may be, for example, a thermocouple, an infrared radiation thermometer, or the like. A plurality of temperature detectors may be provided, in which case the average of the temperatures measured by each detector can be used as the temperature of the work.

The means for controlling the work temperature adjusting means controls the work temperature adjusting means based on the information obtained by the work temperature detector and the target work temperature (work set temperature). It is electrically connected to the temperature detector and the work temperature adjusting means, and forms an electric circuit with them. For example, when the temperature near the work surface of the work measured by the work temperature detector is higher than the set temperature, the control unit is required to promote cooling by the work temperature adjustment unit. An electric signal is sent to the work temperature control means. It is desirable in terms of efficiency that the control of the temperature adjusting means by the control means be automatically performed, for example, by a computer.

The preferable range of the temperature of the work detected by the work temperature detector is determined according to the type of the polishing liquid and the work, the polishing conditions, and the like. For example, when an insulating film made of SiO ₂ or the like is formed on a semiconductor wafer and the insulating film is polished using a polishing liquid in which SiO ₂ or the like is dispersed as abrasive grains in an aqueous ammonia solution, a good polishing rate is required. It is preferable to control the temperature of the work to 50 to 70 ° C. in order to secure the temperature and prevent the agglomeration of the abrasive grains due to the temperature rise of the polishing liquid.

The retainer ring is provided to prevent excessive polishing on the outer periphery of the work. Therefore, the retainer ring surrounds the entire circumference of the work, and is arranged such that one surface thereof is flush with the work surface of the work as a polishing surface. For the retainer ring, a conventionally used one can be used. For example, a polyacetal resin (for example, PO
Materials consisting of engineering plastics such as M) can be used.

The retainer ring and the work are simultaneously polished by the polishing pad. However, since the retainer ring and the work are made of different materials, the frictional heat generated during the polishing is different due to the difference in the thermal conductivity. The temperatures on the polishing surface of the retainer ring will be different from each other. Therefore, in the present invention, the temperature of the retainer ring is controlled by an independent temperature control system.

The retainer ring temperature adjusting means and the retainer ring temperature detector are preferably installed on the side opposite to the polished surface of the retainer ring so as to be as close as possible to the retainer ring, and come into contact with the retainer ring. It is more preferable to install it. If it is away from the retainer ring, it becomes difficult to efficiently heat or cool the retainer ring, and the temperature of the retainer ring cannot be detected correctly.

The means for controlling the retainer ring temperature control means, the retainer ring temperature detector and the means for controlling the retainer ring temperature control means are the same as the means for controlling the work temperature control means, the work temperature detector and the work temperature control means, respectively. is there. Therefore, the detailed description is omitted here. The means for controlling the work temperature control means and the means for controlling the retainer ring temperature control means may exist as one control device as long as the work and the retainer ring temperature control means can be independently controlled.

Generally, a retainer ring made of a polyacetal resin such as POM tends to accumulate heat and thus tends to increase in temperature. Since a rise in temperature causes deformation of the retainer ring, the temperature of the retainer ring during polishing is reduced to 60 degrees.
It is preferable that the temperature is cooled to not more than ℃.

In the second polishing apparatus of the present invention, it is preferable that the work and the retainer ring have a rotating means that can rotate integrally. Specifically, it is preferable to dispose the work and the retainer ring on a turntable that can rotate (rotate) about the central axis as a rotation axis. In that case, the wiring connected to the work and the retainer ring temperature adjusting means and the work and the retainer ring temperature detector are rotatably supported by bearings through the through holes formed in the spindle shaft of the turntable, and are internally mounted on the spindle. It is preferable that the electric wiring provided inside the spindle is connected to a means for controlling the work and the retainer ring temperature adjusting means through a hollow slip ring.

When the retainer ring itself does not have sufficient strength, the cross-sectional shape in the direction perpendicular to the thickness direction on the surface opposite to the polished surface of the retainer ring is the same as that of the retainer ring. It is advisable to arrange a backup plate to support the retainer ring. In that case, the retaining ring temperature adjusting means and the retaining ring temperature detector are attached to the backup plate. Therefore, the backup plate is preferably made of a material having a high thermal conductivity so that the retainer ring temperature control means can efficiently heat or cool the retainer ring, and specifically, made of Teflon-coated stainless steel. Preferably, it is When a backup plate is used and a turntable is used, the backup plate is placed on the turntable.

FIG. 3 shows an example of the work and retainer ring temperature control system described above. FIG.
In, the work (31) is fixed to a fixed plate (35) including a suction plate (32) and a vacuum space (33) by vacuum suction. The temperature control system for the work (31)
It includes a temperature detector (36a) and a thermoelectric cooling element (37a) embedded in 5), and a comparison circuit (48) electrically connected to them. Retaining ring (38)
Are arranged all around the work (31), and the backup plate (3
Supported by 9). The temperature control system of the retainer ring (38) includes a temperature detector (36b) arranged below the backup plate (39) and a thermoelectric cooling element (37).
b), as well as a comparison circuit (48) electrically connected to them.

In the illustrated embodiment, the temperature information signal (53) from the temperature detector (36a) of the work (31) is compared with the set temperature signal (50a) by the comparison circuit (48), and the comparison result is the control signal. The signal is sent to the amplifier circuit (49) as (54). The control signal (54) sent to the amplifier circuit (49) converts the set temperature signal (50b) amplified by the amplifier circuit (49) to the work (31) appropriately based on the temperature information (53). Vary to get. The changed signal is sent to the thermoelectric cooling element (37a) as a voltage signal (55) for applying a voltage. The temperature of the retainer ring (38) is similarly controlled. FIG. 3 shows only signals related to temperature control of the work (31) in order to avoid complication of the drawing.

Work (31) and retainer ring (38)
Are fixed plate (35) and backup plate (39) respectively
It is placed on the turntable (40) via. Temperature detector (36a) (36b) and thermoelectric cooling element (37a)
The electrical wiring (44) leading to the outside from (37b)
It is passed through a through hole formed in the spindle shaft (41), is rotatably supported by a bearing (43), and is housed in the spindle (42). The spindle shaft (41) has a hollow tubular path (34) at the center thereof as a fluid path (45) for vacuum suction, and an electric path for arranging electric wiring (44) therearound. (46) Yes. The rotating electric path (46) is connected to a comparison circuit (48) and an amplification circuit (49) via a hollow slip ring (47). The hollow tubular channel (34) is connected to a rotary joint (51) from which a vacuum pump or a pure water supply (52) for cleaning the adsorption surface
Connected to.

As described above, the second polishing apparatus according to the present invention is characterized in that the temperature control of the workpiece and the retainer ring is performed independently. However, when the retainer ring is made of a material having physical and chemical properties similar to the work, for example, SiC or SiO ₂ , the amount of heat generated in the work and the retainer ring becomes equal, so that the work temperature adjusting means is used. It is also possible to control the retainer ring temperature adjusting means by one control means.

The temperature control system for the polishing pad of the first polishing apparatus and the temperature control system for the work and the retaining ring of the second polishing apparatus described above may be used in combination. In this case, for example, the polishing may be performed by pressing the polishing pad of the polishing tool shown in FIG. 1 against the work shown in FIG. 3 from above and rotating the polishing pad, the work, and the retainer ring. In that case, the temperature of the fluid to be supplied to the space in the polishing pad holder, the temperature of the work, and the temperature of the retainer ring may be controlled to be different from each other. For example, an insulating film made of SiO ₂ or the like is formed on a semiconductor wafer, and the insulating film is formed on an aqueous ammonia solution using SiO 2.
_When polishing using a polishing liquid in which ₂ or the like is dispersed as abrasive grains, the temperature of the fluid supplied to the space is 20 to 80 ° C., the temperature of the work is 50 to 70 ° C., and the temperature of the retainer ring is 6
It is preferable to control the temperature to 0 ° C. or lower.

The temperature range described in the above description is particularly suitable for polishing an oxide film formed on a semiconductor wafer, and a preferable temperature range depends on the material and shape of the work surface of the work. The range changes.

In the above, the polishing apparatus and the polishing method of the present invention have been described mainly with respect to the temperature control system of the polishing pad, and the temperature control system of the work and the retainer ring. However, other members or elements are conventionally used. Or JP-A-7-20178
No. 8 can be arbitrarily adopted. For example, the polishing tool may include driving means for rotating the polishing pad, and means for moving the polishing tool to bring the polishing pad closer to the work. Further, the polishing tool may be one that can swing the polishing pad in the horizontal direction during polishing by a suitable driving means.

Further, the polishing apparatus and the polishing method of the present invention are not applied only to polishing by the CMP method.
Mechanical polishing (MP) and mechanochemical polishing (MCP)
ishing) method.

[0083]

According to the polishing apparatus and the polishing method of the present invention, the temperature of the polishing pad and / or the temperature of the work and the retainer ring in the vicinity of the work surface of the work can be controlled within a predetermined range, thereby efficiently polishing the work. Is effected. Further, by exchanging heat between the polishing pad and a fluid flowing in a space in the polishing pad holder, the polishing pad is prevented from being exposed to a high temperature, and the life of the polishing pad is improved. Can be. Further, by independently controlling the temperature of the retainer ring, it is possible to effectively prevent the retainer ring from being deformed by high heat.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a temperature control system for a polishing pad of a polishing apparatus according to the present invention.

FIG. 2 is a schematic sectional view showing an example of a temperature control system for a polishing pad of the polishing apparatus of the present invention.

FIG. 3 is a schematic cross-sectional view showing an example of a temperature control system for a workpiece and a retainer ring of the polishing apparatus of the present invention.

FIG. 4 is a schematic sectional view showing an example of a conventional polishing apparatus.

[Explanation of symbols]

100 ... polishing tool, 1 ... polishing pad, 2 ... elastic body,
3 ... inner peripheral side mounting member, 4 ... outer peripheral side mounting member, 5 ... polishing pad holder, 5a ... shaft part of polishing pad holder, 6 ... polishing liquid, 7 ... polishing Liquid supply source, 8 ... polishing liquid supply path, 9 ... fluid supply source, 10 ... pressure regulating valve, 11 ... fluid, 12 ... heat exchanger, 13 ... first path , 14 ... space, 15 ...
2nd path, 16 ... Flow regulating valve, 17 ... Pressure gauge, 18 ... Temperature detector, 19 ... Control means, 21 ... First electropneumatic regulator,
22 ... External signal, 23 ... Second electropneumatic regulator, 23a ...
Valve, 24 ... External signal, 31 ... Work, 32 ... Suction cup, 33 ...
Vacuum space, 34 ... hollow tubular path, 35 ... fixed plate, 36a ... work temperature detector, 36b ... retainer ring temperature detector, 3
7a ... Work temperature control means (thermoelectric cooling element), 37b ...
Retaining ring temperature control means (thermoelectric cooling element), 38 ...
Retainer ring, 39 ... Backup plate, 40 ... Turntable, 41 ... Spindle shaft, 42 ... Spindle, 43 ...
Bearing, 44 ... Electrical wiring, 45 ... Fluid path, 46 ... Electrical path, 47 ... Slip ring, 48 ... Comparison circuit, 49 ... Amplification circuit, 50a, 50b ... .Set temperature signal, 51 ... Rotary joint, 52 ... Vacuum pump or pure water supply source, 53 ... Temperature information signal, 54 ... Control signal, 55 ... Voltage signal, 401 ... Polishing pad, 402 ... elastic body, 403 ... space, 404 ... work.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsuyoshi Shingu 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 3C058 AA07 AA09 AA12 AB04 AC04 BA05 BA08 BB04 CB01 CB03 DA17

Claims (14)

[Claims] 1. A polishing apparatus comprising a system for controlling a temperature of a polishing pad, the system comprising: 1) a polishing pad, an elastic body attached to a surface of the polishing pad opposite to a polishing surface, And polishing pad holder,
The polishing pad holder has a shaft portion extending perpendicular to the polishing surface of the polishing pad, and a polishing tool in which a space is formed in the polishing pad holder so as to contact the polishing pad via an elastic body. 2) a first path for supplying a fluid to the space, a first path partially passing through a shaft of a polishing pad holder; 3) a second path for discharging a fluid from the space. A second path partially passing through the shaft of the polishing pad holder; 4) means for controlling the temperature of the fluid supplied to the space;
And 5) a polishing apparatus comprising means for controlling a pressure of a fluid in the space. 2. The polishing apparatus according to claim 1, wherein the means for controlling the pressure includes pressure adjusting means for setting a pressure of the fluid in the first path to a predetermined value. 3. The pressure control device according to claim 1, wherein the pressure control unit includes a pressure adjustment unit that sets the pressure of the fluid in the first path to a predetermined value, and a pressure adjustment unit that sets the pressure of the fluid in the second path to a predetermined value. The polishing apparatus according to claim 1, wherein: 4. The apparatus of claim 1 wherein said means for controlling pressure comprises a first electropneumatic regulator connected to a first path and a second electropneumatic regulator connected to a second path. Item 4. The polishing apparatus according to Item 3. 5. The polishing tool according to claim 1, wherein the polishing tool has a polishing liquid supply path which penetrates a shaft portion of the polishing pad holder and discharges the polishing liquid from a central portion of the polishing pad. Polishing equipment. 6. A polishing apparatus comprising a system for controlling the temperature of a work and a retainer ring, the system comprising: 1) a work fixing plate for supporting and fixing the work; 2) a work attached to the work fixing plate. Temperature control means and work temperature detector; 3) means for controlling work temperature control means; 4) retainer ring temperature control means and retainer mounted to be located on the side of the retainer ring opposite to the polishing surface. A polishing apparatus comprising: a ring temperature detector; and 5) means for controlling a retainer ring temperature adjusting means. 7. The polishing apparatus according to claim 6, wherein the work temperature adjusting means and / or the retainer ring temperature adjusting means is a thermoelectric heating element and / or a thermoelectric cooling element. 8. The apparatus according to claim 6, further comprising rotating means for integrally rotating the work and the retainer ring.
A polishing apparatus according to claim 1. 9. The backup plate is provided on a surface of the retainer ring opposite to the polished surface, and the retainer ring temperature adjusting means and the retainer ring temperature detector are attached to the backup plate. The polishing apparatus according to claim 1. 10. A polishing pad temperature control system according to any one of claims 1 to 5, and a workpiece and retainer ring temperature control system according to any one of claims 6 to 9. Polishing equipment. 11. A method of polishing a work by moving a polishing pad relative to the work, comprising: a polishing pad; an elastic body attached to a surface of the polishing pad opposite to a polishing surface; The polishing pad holder includes a polishing pad holder, the polishing pad holder having a shaft portion extending perpendicularly to a polishing surface of the polishing pad, and a space in the polishing pad holder so as to contact the polishing pad via an elastic body. Using the formed abrasive tool, maintaining the pressure of the fluid in the path for supplying the fluid to the space greater than the pressure of the fluid in the path for discharging the fluid from the space, and supplying the fluid to the space; By discharging the fluid from the space, a flow of the fluid is generated in the space, and the pressure of the fluid in the space is kept substantially at a predetermined value. By transmitting a force to the polishing pad via the elastic body, the polishing pad is pressed against the work, the temperature of the fluid supplied to the space is controlled to a temperature within a predetermined range, and heat exchange between the fluid and the polishing pad is performed. A polishing method characterized by causing polishing. 12. A method of polishing a work by moving a polishing pad relative to the work, wherein the temperature of the work supported on the work fixing plate is controlled by adjusting the temperature of the work opposite to the work surface of the work. The temperature of the retainer ring provided around the work is controlled by controlling the work temperature adjusting means located at the side of the surface opposite to the polishing surface of the retainer ring. A polishing method for controlling a temperature within a predetermined range by controlling a retainer ring temperature adjusting means. 13. A method of polishing a work by moving a polishing pad relative to the work, comprising: a polishing pad; an elastic body attached to a surface of the polishing pad opposite to a polishing surface; A polishing tool including a polishing pad holder, wherein a space is formed in the polishing pad holder so as to be in contact with the polishing pad via an elastic body, and a pressure of the fluid in a path for supplying a fluid to the space from the space. Maintaining a pressure higher than the pressure of the fluid in the path for discharging the fluid, supplying a fluid to the space and discharging the fluid from the space to cause a flow of the fluid in the space, Maintaining the pressure at a substantially predetermined value, pressing the polishing pad against the work by transmitting the pressure of the fluid in the space to the polishing pad via the elastic body, The temperature of the fluid supplied to the space is controlled to a temperature within a predetermined range, heat exchange occurs between the fluid and the polishing pad, and the temperature of the workpiece supported by the workpiece fixing plate is adjusted to the work surface of the workpiece. The temperature of the retainer ring provided around the work is controlled by controlling the work temperature adjusting means located on the opposite side of the work so that the temperature is within a predetermined range. A polishing method comprising: controlling a temperature within a predetermined range by controlling a retainer ring temperature adjusting means located on a side surface side. 14. The polishing method according to claim 11, wherein a polishing liquid having a temperature within a predetermined range is supplied.