JP2003133271A - Chemical mechanical polishing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deteriorated productivity or the like due to error detection in a CMP apparatus comprising a mechanical detection mechanism for detecting the presence or absence of a wafer in a carrier head. SOLUTION: The chemical mechanical polishing apparatus which comprises three carrier heads 31-34 for absorbing and holding a wafer, a removable table 51, and three platens 61, 71 and 81 for pressing and polishing the wafer held by the carrier heads, and has mechanical detection mechanisms in the carrier heads, wherein four reflex optical sensors 120 are provided on a top face of a base 20 outside the carrier heads 31-34. This structure improves polishing efficiency as well as productivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical mechanical polishing apparatus for flattening a semiconductor substrate or the like as an object to be processed by chemical and mechanical polishing (CMP), and more particularly to holding a semiconductor substrate against a carrier head. The present invention relates to a chemical mechanical polishing device provided with a detection mechanism for mechanically detecting whether or not it has been removed.

[0002]

2. Description of the Related Art A chemical mechanical polishing apparatus (CMP apparatus) is known as an apparatus for flattening the surface of a semiconductor substrate (hereinafter, simply referred to as a wafer) as an object to be processed which has been subjected to various lamination processes. . This device holds a wafer with a carrier head, presses the wafer against a polishing pad on a platen, and supplies a polishing agent (slurry) while rotating the carrier head and the platen (rotary base) to chemically remove the wafer surface. And it is mechanically polished.

In this device, as shown in FIG.
The housing 2, the holding ring 3 formed in an annular shape on the outer circumference of the housing 2, the movable holding member 4 supported in the inner space of the holding ring 3 so as to be movable in the vertical direction, and arranged in close contact with the lower surface of the movable holding member 4. A membrane (flexible membrane) 5 that can be elastically deformed by a change in pressure or the like is provided. The movable holding member 4 defines the chamber C and has a plurality of first through holes 4a communicating with the chamber C on the lower surface portion to which the membrane 5 is attached, and one first through hole 4a having an opening diameter larger than the first through hole 4a. 2 through holes 4b, a passage 4c for connecting a suction pump (not shown) to the chamber C, and the like.

Further, in the above apparatus, since the wafer W needs to be accurately held by the carrier head 1 (movable holding member 4) during the polishing process, a mechanical device for detecting the presence or absence of the wafer W is required. A different detection mechanism is provided. This detection mechanism is configured by a passage 6 which is partially provided in the movable holding member 4 and is opened to the atmosphere, an opening / closing valve 7 that opens and closes the passage 6, a spring 8 that urges the opening / closing valve 7 in the closing direction, and the like. Has been done.

In the above apparatus, as shown in FIG. 7A, when the pressure in the chamber C is reduced by the suction pump with the wafer W placed on the lower surface of the membrane 5, the first through hole 4a and the first through hole 4a The membranes 5 ′ and 5 ″ located in the two through holes 4 b are deformed by being sucked inward, and a low pressure pocket LP is generated between the membrane 5 ′ and the wafer W.
These low-pressure pockets LP act as suction cups to adsorb the wafer W. Therefore, the wafer W is firmly held by the movable holding member 4. At this time, the membrane 5 ″ corresponding to the second through hole 4b is deformed to a level at which it does not come into contact with the opening / closing valve 7 due to the pressure in the low pressure pocket LP, so that the opening / closing valve 7 closes the passage 6. To maintain.

On the other hand, as shown in FIG. 7B, when the inside of the chamber C is decompressed by the suction pump without the wafer W on the lower surface of the membrane 5, the first through hole 4a and the second through hole 4b are formed. The membranes 5 ′ and 5 ″ located at are deformed by being sucked inward, but due to the absence of the wafer W, they are deformed more than in the case shown in FIG. 7A. As a result, the membrane 5 corresponding to the second through hole 4b
″ Is in contact with the opening / closing valve 7 and further pushes the opening / closing valve 7 upward against the biasing force of the spring 8.
The opening / closing valve 7 opens the passage 6. As a result, even if the inside of the chamber C is continuously depressurized by the suction pump, the passage 6 is opened to the atmosphere, so that the pressure inside the chamber C does not become lower than the predetermined level.

That is, in the above detection mechanism, FIG.
As shown in FIG. 7, when the pressure in the chamber C is detected by a pressure sensor (not shown) and the value is P1 (see FIG. 7).
(In the state shown in (a)), it is determined that the wafer W is present (held), and its value is P2 (P2>
In the case of P1) (in the state shown in FIG. 7B), it is determined that the wafer W is absent (not held).

[0008]

In the mechanical detection mechanism as described above, the opening / closing valve 7 sticks to and from the reciprocating guide passage due to variations in assembling accuracy, operating environment, temporal factors, and the like. And so on,
As shown in FIG. 9, there is a case in which the passage 6 is not completely restored and the passage 6 is stopped while being kept open.

As a result, although the wafer W is adsorbed and held by the membrane 5, the pressure sensor detects the value of P2, and there is no wafer W (wafer W).
Has fallen), it will be judged (erroneous detection). Based on this determination, the control unit that controls the entire operation of the apparatus stops the rotation of the carrier head 1, the platen, etc., and stops the polishing operation. Therefore, the apparatus automatically stops in spite of the presence of the wafer W, so that the polishing work is interrupted in the middle, and the operator must perform a confirmation work each time the interrupting work is performed. Will be reduced.

Contrary to the above-mentioned detection mechanism, a chemical mechanical polishing apparatus having another type of detection mechanism that erroneously detects that the wafer W is present even though it is not present,
If such an erroneous detection is performed, the carrier head 1 and the platen are continuously rotated even though the wafer W is not held, so that the membrane 5 and the holding ring 3 are directly pressed against the polishing pad or the like to polish the wafer. As a result, the membrane 5 may be damaged or damaged, or the polishing pad may be damaged.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a mechanical detection mechanism for detecting the presence or absence of an object to be processed such as a wafer.
Even if an erroneous detection is performed, the frequency of the device stopping based on the detection signal is suppressed, unnecessary checking work is minimized, stable polishing work is maintained, and productivity is improved, or An object of the present invention is to provide a chemical mechanical polishing apparatus that can prevent damage or breakage of components and the like as much as possible in an apparatus including a detection mechanism that erroneously detects that there is no processing object.

[0012]

A chemical mechanical polishing apparatus of the present invention comprises a carrier head for adsorbing and holding an object to be processed,
A chemical mechanical polishing apparatus comprising a rotary base for pressing and polishing an object to be processed held by a carrier head, and a base supporting the rotary base, which is held by a carrier head at a predetermined position on the base. A detection sensor for detecting the presence or absence of the processed object is provided. According to this configuration, even if the mechanical detection mechanism built in the carrier head makes a false detection, another detection sensor arranged on the base outside the carrier head detects the presence or absence of the object to be processed. Therefore, stoppage of the device due to erroneous detection can be prevented as much as possible, or damage to component parts and the like can be prevented as much as possible. In addition, even in a device that does not include a mechanical detection mechanism, the presence or absence of the object to be processed can be detected by this detection sensor.

In the above structure, the detection sensor may be a reflection type optical sensor having a light projecting portion and a light receiving portion. According to this configuration, since it is a non-contact type optical sensor rather than a mechanical sensor, it is possible to prevent erroneous detection due to malfunctions that occur in a conventional detection mechanism, and to perform more reliable detection.

In the above structure, the detection sensor may be arranged near the outer edge of the rotary base. According to this configuration, since the detection sensor is arranged in the vicinity of the outer edge of the rotary base, that is, in the adjacent area on the outer side, other parts (for example, a pad conditioner for adjusting the polishing pad) arranged above the rotary base are arranged. , A slurry supply pipe for supplying an abrasive, etc.) can be prevented from being detected by mistake, and the presence or absence of the object to be processed can be detected more reliably.

Further, the chemical mechanical polishing apparatus of the present invention includes a carousel movably carrying a plurality of carrier heads capable of adsorbing and holding an object to be processed and rotatably arranged around a predetermined rotation axis. An attachment / detachment table for attaching / detaching the object to be processed with respect to the carrier head, a plurality of rotary bases arranged corresponding to each of the plurality of carrier heads for pressing and polishing the object to be processed held by the carrier head,
With a detachable table and a base that supports a rotating base,
A detachable table and a plurality of rotary bases are chemical mechanical polishing devices arranged around the rotation axis of a carousel, and a detection sensor for detecting the presence or absence of an object to be processed held by the carrier head at a position outside the carrier head. Is provided,
It is characterized by that. According to this configuration, when the object to be processed held by the carrier head is transferred from the removable tape to the adjacent rotary base or from one rotary base to another adjacent rotary base, the carrier head is Even if the built-in mechanical detection mechanism makes a false detection,
Since another detection sensor arranged on the base outside the carrier head detects the presence or absence of the object to be processed, stoppage of the device due to erroneous detection can be prevented as much as possible, or damage to component parts and the like can be prevented as much as possible. As a result, the work of polishing the object to be processed is efficiently performed, and the productivity is improved. In addition, even in a device that does not include a mechanical detection mechanism, the presence or absence of the object to be processed can be detected by this detection sensor.

In the above structure, the detection sensor may be a reflection type optical sensor having a light projecting portion and a light receiving portion. According to this configuration, since it is a non-contact type optical sensor rather than a mechanical sensor, it is possible to prevent erroneous detection due to malfunctions that occur in a conventional detection mechanism, and to perform more reliable detection.

In the above structure, it is possible to adopt a structure in which the detection sensor is arranged in the vicinity of the outer edge of the removable table and in the vicinity of each outer edge of the plurality of rotary bases, and between the rotary shaft of the carousel. According to this configuration,
Even in an apparatus having a plurality of processing stations for attaching / detaching an object to be processed and polishing processing, reliable detection can be performed for each transfer process, so that the frequency of erroneous detection can be suppressed as much as possible and polishing work can be performed more efficiently. Productivity is further improved.

In the above structure, there is provided control means for controlling at least the operations of the carousel, the carrier head and the detection sensor, and the control means controls the object to be processed held by the carrier head as one of a plurality of rotary substrates. When moving from a position facing the rotary base to a position facing another adjacent rotary base, the carrier head is moved backward so that the object to be processed is drawn toward the rotary shaft side of the carousel in advance, and then moved forward in the opposite direction. In addition, it is possible to employ a configuration in which the detection sensor performs a detection operation during the backward movement or the forward movement. According to this configuration, since the object to be processed performs the detection operation at a predetermined timing away from other parts (for example, a pad conditioner, a slurry supply pipe, etc.) arranged above the rotating base, False detection can be reliably prevented, and the presence or absence of the object to be processed can be detected more stably and highly accurately.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 5
1 shows an embodiment of a chemical mechanical polishing apparatus according to the present invention, and FIG. 1 is a schematic plan view showing the entire configuration, FIG.
Is a plan view showing the base, FIG. 3 is a side view showing the relationship between the detection sensor and the object to be processed, FIG. 4 is a block diagram showing the control system, and FIG. 5 is a plan view showing the operation and the operation timing of the detection sensor. is there.

This device has a base 1 as shown in FIG.
0, a carousel 30 rotatably supported by a rotary shaft 20 above the base 10, a transport mechanism 40 that is disposed adjacent to the base 10 and transports a cassette 41 that stores a wafer W as an object to be processed, the entire apparatus The control unit 100 as a control unit for controlling the operation and the like is provided as a basic configuration.

As shown in FIGS. 1 and 2, the base 10 includes a single attachment / detachment station 50 for attachment / detachment of the wafer W, and the attachment / detachment station 50, followed by the rotary shaft 2.
A first polishing station 60, a second polishing station 70, a third polishing station 80, and the like, which are sequentially arranged counterclockwise around 0 (carousel 30), are provided. A cleaning station 90 is arranged between the attachment / detachment station 50 and the three polishing stations 60, 70, 80.

The loading / unloading station 50 temporarily mounts the wafer W when the wafer W is loaded / unloaded to / from carrier heads 31, 32, 33, 34 described later.
1 is provided. 3 polishing stations 60, 70,
Reference numeral 80 is a platen 61, 71, 81 as a rotary base having a polishing pad on the upper surface, and slurry supply pipes 62, 72, 82 forming part of the slurry supply unit.
And pad conditioners 63, 73, 83 and the like.

The platens 61, 71, 81 are each rotationally driven by a drive motor (not shown), and the rotational speed thereof is about 30 rpm to 200 rpm. The slurry supply pipes 62, 72, 82 supply an abrasive (slurry) containing a reaction agent, abrasive particles, a chemical reaction catalyst, etc., to the surface of the polishing pad, and a plurality of high-pressure rinses for the polishing pad. Also equipped with a rinse nozzle. The pad conditioners 63, 73, and 83 are the adjustment heads 6 respectively.
3a, 73a and 83a are provided to maintain the polishing pad in an optimum state so as to efficiently polish the wafer W pressed against the polishing pad.

The carousel 30 includes four carrier heads 3.
1, 32, 33, 34 are carried. The carrier heads 31, 32, 33, 34 are respectively rotated by drive motors (not shown), and a suction system for adsorbing the wafer W, and the adsorbed wafer W as a polishing pad on the platens 61, 71, 81. A pressing system for pressing, a mechanical detection mechanism for detecting the presence or absence of the wafer W, and the like are provided. Since the suction system, the detection mechanism, and the like have the same structure as the conventional structure shown in FIGS. 6 and 7, description thereof will be omitted here.

The carrier heads 31, 32, 33,
34 includes drive mechanisms 31a, 32a, 33a,
34a is provided. Drive mechanism 31a, 32a, 3
3a and 34a are corresponding carrier heads 3
1, 32, 33, 34 are moved (retracted) toward the rotating shaft 20 in the direction D in the plane parallel to the upper surfaces of the platens 61, 71, 81, and are also moved away from the rotating shaft 20. The platen 61, 71, 81 is moved downward (moved forward) and further moved downward and upward in the vertical direction perpendicular to the upper surfaces of the platens 61, 71, 81.

On the upper surface of the base 10, as shown in FIG. 2, four detection sensors 120 (120a, 120b, 1) are provided.
20c, 120d) are arranged. These four detection sensors 120 are mounted on a ring bracket 130 arranged outside the rotary shaft 20 and fixed to the base 10, and are supported at an angular interval of approximately 90 degrees from each other.

The detection sensor 120, as shown in FIG.
A light projecting unit 121 that projects detection light, a light receiving unit 122 that receives the reflected light in which the detection light projected from the light projecting unit 121 is reflected by the front surface (lower surface) of the wafer W, the light projecting unit 121, and the light receiving unit. It is a so-called reflection type optical sensor (photointerrupter) configured by a housing 123 or the like that holds 122. The light projecting portion 121 is composed of a light emitting diode, and its tip portion 121a is rounded so as to form a hemispherical surface. The light receiving portion 122 is formed of a light receiving element, and its tip portion 122a is rounded so as to form a hemispherical surface. The housing 123 is a ring bracket 130.
The housing 123 can be finely adjusted in angle, height and the like.

Since the polishing processing space in which the detection sensor 120 is disposed is in an environment of adverse conditions in which abrasives (slurry), polishing powder, etc. are scattered, these are also formed on the surfaces of the light projecting section 121 and the light receiving section 122. May be attached to In this case, the tip portions 121 of the light projecting portion 121 and the light receiving portion 122
Since the a and 122a are formed in a round shape so as to form a hemispherical surface, the adhering substances immediately flow downward and do not hinder the functions of light projection and light reception. In particular,
When an optical sensor is used in an environment space where chemical mechanical polishing is performed, the light projecting unit 121 and the light receiving unit 12 are used as described above.
To form the tip portions 121a and 122a of the second round shape,
It is effective in increasing the detection accuracy. The rounded shape is not limited to the hemispherical shape as long as the attached matter can be easily separated.

The light projecting section 121 and the light receiving section 122 are
When being positioned with respect to the lower surface of the wafer W held by the carrier heads 31, 32, 33, 34, as shown in FIG. 3, it is line-symmetric with respect to a line V perpendicular to the lower surface of the wafer W. And the angle θ formed by the optical axis L1 of the light projecting portion 121 and the optical axis L2 of the light receiving portion 122, and from the light projecting end and the light receiving end of the light projecting portion 121 and the light receiving portion 122 to the lower surface of the wafer W. To the distance H to the angle θ
Is set to about 60 to 80 degrees, preferably about 70 degrees, and the distance H is about 8 mm to 12 mm, preferably 10 degrees.
It is set to about mm. Thus, the detection sensor 120
By locating, it is possible to prevent erroneous detection and detect the presence or absence of the wafer W with high accuracy.

Further, as shown in FIG. 2, the four detection sensors 120 are respectively attached to the detachable table 51 and the platen 6.
They are arranged in the vicinity of the outer edges of 1, 71 and 81 and between them and the rotary shaft 20. That is, each detection sensor 120
Is positioned and fixed on or near a line connecting the centers of the removable table 51 and the platens 61, 71, 81 and the center of the rotary shaft 20.

As described above, since the detection sensor 120 is arranged corresponding to each of the attachment / detachment table 51 and the three platens 61, 71, 81, the carrier heads 31, 32, 33, 34 holding the wafer W are The presence or absence of the wafer W can be detected for each station regardless of which station area it is. That is, the attachment / detachment station 50 and the three polishing stations 60,
Since it is possible to detect the presence or absence of the wafer W for each transfer process between the 70 and 80, even if the mechanical detection mechanism causes an erroneous detection, the frequency of stopping the device due to the erroneous detection can be suppressed as much as possible. it can. As a result, it is possible to prevent the polishing work from being unnecessarily stopped and to efficiently perform the polishing work.

As described above, by disposing the detection sensor 120 near the outer edges of the attachment / detachment table 51 and the three platens 61, 71, 81 and between the rotation shaft 20 and the detection sensor 120, the detection sensor 120 in the wafer W is It is possible to prevent other components and the like from being erroneously detected, and erroneously detect that the wafer W is present. In particular, each polishing station 60, 70,
In the area 80, above the platens 61, 71, 81, not only the carrier heads 31, 32, 33, 34 but also the slurry supply pipes 62, 72, 82, or
Since the pad conditioners 63, 73, 83 and the like are present, the detection light projected from the detection sensor 120 may be reflected by the surfaces of various components and returned, and a detection signal indicating that the wafer W is present may be output.

Therefore, as described above, the slurry supply pipes 62, 72, 82 or the pad conditioner 6 is used.
By arranging the detection sensor 120 between the rotary shaft 20 and the space where the 3, 3, 83, etc. do not exist, that is, near the outer edges of the attachment / detachment table 51 and the platens 61, 71, 81, detection by components other than the wafer W It is possible to reliably prevent the light from being reflected, and thereby to perform highly accurate detection without erroneous detection.

As shown in FIG. 4, a control unit (control means) 100 is provided in a control system that controls the entire apparatus.
Is a central arithmetic processing unit 110 that performs various arithmetic processes and emits control signals, a storage unit 115 that stores various operation information such as recipe information indicating a procedure of polishing work in advance, and a rotational driving of the carousel 30. Drive circuit 130 that controls the drive heads, drive circuits 31a, 32a, 33a, and 34a that drive the carrier heads 31, 32, 33, and 34a, carrier heads 31, 32, and
A drive circuit 150 for controlling the rotational drive of 33 and 34, and a drive circuit 1 for controlling the rotational drive of the platens 61, 71 and 81.
60, a drive circuit 170 for controlling the drive of the pad conditioners 63, 73, 83, a drive circuit 180 for controlling the drive of the slurry supply system, a detection sensor 120 (120)
a, 120b, 120c, 120d) is provided with a detection circuit 190 for controlling the detection operation (detection timing).

That is, the detection sensor 120 is the wafer W.
For the operation (detection timing) of detecting the presence or absence of the drive mechanism, the drive mechanisms 31a, 32a, 33a, 34a are previously stored in the storage unit 1.
When the carrier heads 31, 32, 33, 34 are appropriately moved based on the recipe information stored in 15, when the carrier heads 31, 32, 33, 34 reach a predetermined position, or within a predetermined range. When it is located at, the detection circuit 190 is activated by the control signal from the central processing unit 110, and the detection operation by the detection sensor 120 is performed.

Next, the operation and detection sensor 12 of the above device.
The detection operation of 0 will be described. Here, for convenience of description, a case will be described in which one wafer W is held by one carrier head 31 and the polishing processing is sequentially performed by the three polishing stations 60, 70, 80.

First, the wafer W taken out of the cassette 41 by the loading / unloading mechanism (not shown) is placed on the attachment / detachment table 51. Then, for example, the carrier head 31
Is driven to adsorb the wafer W, and the carrier head 31
Moves (reverses) in the direction of being attracted to the rotary shaft 20 (direction D1). During this backward movement, the detection sensor 120a is operated at a predetermined timing to detect the presence or absence of the wafer W.

Then, the carousel 30 is rotated counterclockwise by about 9 degrees.
Rotate 0 degrees to position the carrier head 31 on the first polishing station 60. Then, the drive mechanism 31a brings the carrier head 31 closer to a position facing the platen 61, presses the wafer W against the polishing pad, and performs the polishing process.

When the polishing process in the first polishing station 60 is completed, the drive mechanism 31a raises the carrier head 31 away from the polishing pad, and at the same time the rotary shaft 20 is rotated.
Move in the direction (D1 direction) that is pulled to the side (reverse movement)
To do. During this backward movement, the detection sensor 120b is operated at a predetermined timing to detect the presence or absence of the wafer W.

Subsequently, the carousel 30 rotates counterclockwise by approximately 90 degrees in order to move the carrier head 31 to the adjacent second polishing station 70. Then, the drive mechanism 31a moves (forward moves) the carrier head 31 in a direction away from the rotary shaft 20 (direction D2).
During the forward movement, the presence / absence of the wafer W may be detected by operating the detection sensor 120c at a predetermined timing. In this case, the double detection operation is performed before the polishing process is performed in the second polishing station 70, and the frequency of erroneous detection can be more finely suppressed. Then, the carrier head 3 is driven by the drive mechanism 31a.
1 is brought to a position facing the platen 71, the wafer W is pressed against the polishing pad, and the polishing process is performed.

When the polishing process in the second polishing station 70 is completed, the drive mechanism 31a raises the carrier head 31 away from the polishing pad and the rotary shaft 20
Move in the direction (D1 direction) that is pulled to the side (reverse movement)
To do. During this backward movement, the detection sensor 120c is operated at a predetermined timing to detect the presence or absence of the wafer W.

The same applies to the polishing process in the third polishing station 80 and the detection operation by the detection sensor 120d. When the polishing process in the third polishing station 80 is completed, the carousel 30 rotates 270 degrees clockwise. Then, the carrier head 31 is positioned at the position of the attachment / detachment station 50, and the wafer W is detached and taken out.

In the above-described series of polishing processes, when the mechanical detection mechanism outputs a signal indicating that there is no wafer W, as long as each detection sensor 120 outputs a signal indicating that a wafer W exists. The polishing process is continued. That is, when it is determined by the detection signal of the detection sensor 120 that the detection mechanism is performing erroneous detection, the control unit 100 (central processing unit 110) continues the polishing process without stopping the device.

On the other hand, if the detection sensor 120 determines that there is no wafer W (the wafer W has fallen off) regardless of the signal from the detection mechanism, the control unit 100 (central processing unit 110) outputs the control signal. Is issued and all operations stop. After that, the operator confirms the wafer W, removes the dropped wafer W, and the like.

In the series of polishing processing and detection operations described above, in the apparatus having a plurality of processing stations, particularly when the wafer W is transferred from one processing station (platen) to the adjacent processing station of the next process. Since the detection operation is performed by the detection sensor 120, reliable detection can be performed for each transfer stroke, and the frequency of erroneous detection can be suppressed as much as possible. This improves the efficiency of the polishing operation and improves the productivity.

The carrier head 31 (32, 33,
34) is moved (backward movement or forward movement) between the rotary shaft 20 and the platens 61, 71, 81, the detection light is reflected by other parts in order to cause the detection sensor 120 to perform a detection operation. Therefore, it is possible to prevent erroneous detection and more stably detect the presence or absence of the wafer W with high accuracy.

In the above series of operations, the detection mechanism erroneously detects that the wafer W is not held even though it is held, but conversely, the wafer W is held when the wafer W is not held. In the case of erroneously detecting that the wafer W is not held, the carrier heads 31, 32, 33, 34 and the platens 61, 71,
81 can be activated to prevent damage or breakage of the membrane, polishing pad, or other components.

In the above embodiment, a plurality of carrier heads 31, 32, 33, 34 and a plurality of platens 6 are provided.
In the chemical mechanical polishing apparatus including 1, 71, 81, separate detection sensors 120 (120a, 120b, 120c, 12) are provided outside the carrier heads 31, 32, 33, 34.
0d) is provided, but the present invention is not limited to this, and even in the case where automatic continuous polishing processing is performed in an apparatus equipped with a single carrier head and platen, a separate The detection sensor can be used.

[0049]

As described above, according to the chemical mechanical polishing apparatus of the present invention, as a means for detecting the presence or absence of the object to be processed which is held by adsorption on the carrier head, a conventional mechanical type detection mechanism is used. In addition to the above, by providing a detection sensor that is arranged on the base that is outside the carrier head, even if the conventional detection mechanism makes an erroneous detection, this separate detection sensor ensures that Since the presence / absence is detected, the frequency of stopping the device due to erroneous detection can be suppressed as much as possible, and the productivity can be improved. In addition, even if a processing mechanism that erroneously detects that the object to be processed is not held is provided, the separate detection sensor reliably detects the presence or absence of the object to be processed. It is possible to prevent damage to parts.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of a chemical mechanical polishing apparatus according to the present invention.

FIG. 2 is a plan view showing an upper surface of a base to which a detection sensor is attached.

FIG. 3 is a side view showing a relationship between a detection sensor and a wafer held by a carrier head.

FIG. 4 is a block diagram showing a control system of an apparatus according to the present invention.

FIG. 5 is a plan view illustrating the operation of the measure according to the present invention and the detection timing of the detection sensor.

FIG. 6 is a cross-sectional view showing a structure of a carrier head and a structure of a mechanical detection mechanism.

FIG. 7 is a view for explaining the operation of a mechanical detection mechanism incorporated in the carrier head, and FIG. 7A is a cross-sectional view showing a state in which the detection mechanism is operating normally with a wafer being sucked; FIG. 6B is a cross-sectional view showing a state in which the detection mechanism is normally operating in a state where the wafer is not adsorbed.

FIG. 8 is a graph showing a pressure signal based on the operation of the detection mechanism.

FIG. 9 is a cross-sectional view showing a state in which a mechanical detection mechanism causes an erroneous detection when a wafer is sucked.

[Explanation of symbols]

C chamber 4 movable holding member 5 membrane 6 passage (detection mechanism) 7 opening / closing valve (detection mechanism) 8 spring (detection mechanism) 10 base 20 rotary shaft 30 carousel 31, 32, 33, 34 carrier head 31a, 32a, 33a, 34a Drive mechanism 50 Attachment / detachment station 51 Attachment / detachment table 60 First polishing station 70 Second polishing station 80 Third polishing station 61, 71, 81 Platen (rotary base) 62, 72, 82 Slurry supply pipe 63, 73, 83 Pad Conditioner 90 Cleaning station 100 Control unit (control means) 110 Central processing unit (control means) 120 (120a, 120b, 120c, 120d)
Detection sensor (light sensor) 121 Light emitting unit 122 Light receiving unit 130 Ring bracket

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshihiro Tanaka             14-3 Shinizumi, Narita City, Chiba Prefecture Nogedaira Industrial Park             Uchi Applied Materials Japan Co., Ltd.             In the company (72) Inventor Hiroshi Ishiwatari             14-3 Shinizumi, Narita City, Chiba Prefecture Nogedaira Industrial Park             Uchi Applied Materials Japan Co., Ltd.             In the company (72) Inventor Akimatsu Akihiro             14-3 Shinizumi, Narita City, Chiba Prefecture Nogedaira Industrial Park             Uchi Applied Materials Japan Co., Ltd.             In the company F-term (reference) 3C058 AA07 AB03 BA09 CB06 DA17

Claims (7)

[Claims] 1. A chemistry comprising a carrier head for adsorbing and holding an object to be processed, a rotary base for pressing and polishing the object to be processed held by the carrier head, and a base for supporting the rotary base. A mechanical polishing apparatus, comprising a detection sensor for detecting the presence or absence of an object to be processed held by the carrier head, at a predetermined position on the base. 2. The chemical mechanical polishing apparatus according to claim 1, wherein the detection sensor is a reflection type optical sensor having a light projecting portion and a light receiving portion. 3. The chemical mechanical polishing apparatus according to claim 1, wherein the detection sensor is arranged near an outer edge of the rotary base. 4. A carousel movably carrying a plurality of carrier heads capable of adsorbing and holding an object to be processed and rotatably arranged around a predetermined rotation axis, and attachment / detachment of the object to / from the carrier head. And a plurality of rotary bases arranged corresponding to each of the plurality of carrier heads for pressing and polishing the object to be processed held by the carrier head, and supporting the removable table and the rotary base. A detachable table and a plurality of rotating bases arranged around the rotation axis, wherein the removable head and the plurality of rotating bases are arranged around the rotation axis, and are held by the carrier head at a predetermined position on the base. A chemical mechanical polishing device comprising a detection sensor for detecting the presence or absence of a body. 5. The chemical mechanical polishing apparatus according to claim 4, wherein the detection sensor is a reflection type optical sensor having a light projecting portion and a light receiving portion. 6. The detection sensor is arranged in the vicinity of the outer edge of the removable table and in the vicinity of the outer edge of each of the plurality of rotation bases, and between the rotation sensor and the rotation axis of the carousel. The chemical mechanical polishing apparatus according to claim 4 or 5. 7. A control means for controlling at least operations of the carousel, the carrier head, and the detection sensor, wherein the control means controls the object to be processed held by the carrier head to the plurality of rotary substrates. When moving from a position facing one rotary base to a position facing another rotary base adjacent to the rotary base, the carrier head is moved backward so that the object to be processed is attracted to the rotary shaft side in advance, and then in the reverse direction. 7. The chemical mechanical polishing apparatus according to claim 4, wherein the detection sensor is caused to perform a detection operation during the backward movement or forward movement.