TWI834628B - Magnetic element and eddy current sensor using the same - Google Patents

Abstract

Provided are a magnetic element that makes a magnetic field formed on an object to be polished stronger and an eddy current detector using the magnetic element. The eddy current detector has a bottom portion that is a magnetic body, a magnetic core portion provided at the center of the bottom portion, and a peripheral wall portion provided at a peripheral portion of the bottom portion. The eddy current detector also has an excitation coil arranged on the outer periphery of the magnetic core part and capable of generating a magnetic field; and an excitation coil arranged on the outer periphery of the peripheral wall part capable of generating a magnetic field.

Description

Magnetic components, and eddy current detectors using the magnetic components

The present invention relates to a magnetic element and an eddy current detector using the magnetic element.

In recent years, with the advancement of high-level integration of semiconductor devices, circuit wiring has become increasingly finer, and the distance between wirings has become narrower. Here, it is necessary to flatten the surface of the semiconductor wafer as the object to be polished, and as one method of this flattening method, grinding (polishing) is performed with a grinding device.

The polishing device includes a polishing table for holding a polishing pad for polishing an object to be polished, and a top ring for holding the object to be polished and pressing it against the polishing pad. The grinding table and the top ring are respectively driven to rotate by a driving part (such as a motor). The object to be polished is polished by causing the liquid (slurry) containing the abrasive to flow on the polishing pad and pressing the object to be polished held by the top ring against it.

In a polishing device, if the object is not polished sufficiently, the circuits will not be insulated, and short circuits may occur. In addition, if the object is polished excessively, the cross-sectional area of the wiring will decrease, resulting in an increase in resistance, or the wiring itself will be completely removed, and the circuit itself cannot be formed. Therefore, in a polishing device, it is necessary to detect the optimal polishing end point.

As the technology described above, there is a structure described in Japanese Patent Application Laid-Open No. 2017-58245. In this technology, an eddy current detector using a so-called can-type coil is used to detect the polishing end point. [Prior art documents] [Patent documents]

[Patent Document 1] Japanese Patent Application Publication No. 2017-58245

[Problem to be solved by the invention]

On the surface of the object to be polished, metal may be distributed in a broad surface (lump shape) or fine wiring such as copper may be locally present on the surface. When the surface exists locally, it is required that the eddy current density flowing through the object to be polished becomes larger than when the metal is distributed in a wide plane. That is, the eddy current detector will change the magnetic field formed by the object to be polished. Be stronger.

One aspect of the present invention is to solve the above-mentioned problems, and an object thereof is to provide a magnetic element that makes the magnetic field of an object to be polished stronger and an eddy current detector using the magnetic element. [Means used to solve problems]

In order to solve the above problem, in a first aspect, a magnetic element is used, which is characterized by having: a bottom magnetic body; a central magnetic body provided in the center of the bottom magnetic body; and a peripheral magnetic body. A magnetic body is provided on the peripheral portion of the bottom magnetic body; an inner coil is disposed on the outer periphery of the central magnetic body and is capable of generating a magnetic field; and an outer coil is disposed on the peripheral magnetic body. of the outer circumference and can generate a magnetic field.

In this embodiment, there is an external coil arranged on the outer periphery of the peripheral magnetic body and capable of generating a magnetic field. Therefore, conventionally, only the inner coil capable of generating a magnetic field is arranged on the outer periphery of the central magnetic body. However, according to this embodiment, the magnetic field can be strengthened more than conventionally.

A second aspect uses the magnetic element according to the first aspect, wherein the bottom magnetic body has a columnar shape, and the peripheral magnetic bodies are arranged at both ends of the columnar shape. The magnetic element can be an E-shaped coil, for example.

A third aspect is the magnetic element according to the first aspect, characterized in that a plurality of the peripheral magnetic bodies are provided in a peripheral part of the bottom magnetic body. The number of peripheral magnetic bodies can be two, three, four, six, etc., and it can be a multi-pole coil.

A fourth aspect uses the magnetic element according to the first aspect, wherein the peripheral magnetic body is a wall provided at a peripheral part of the bottom magnetic body and surrounds the central magnetic body. The peripheral magnetic body may have a cylindrical shape, a quadrangular cylindrical shape, or the like. These shapes are the same as those of conventional can-type coils. However, in the conventional can-shaped coil, there is no external coil that is arranged on the outer periphery of the peripheral magnetic body and can generate a magnetic field. Therefore, the fourth aspect can strengthen the magnetic field more than the conventional pot-shaped coil phase.

A fifth aspect is the magnetic element according to any one of the first to fourth aspects, wherein the inner coil and the outer coil are electrically connected in parallel.

In a sixth aspect, the magnetic element according to any one of the first to fifth aspects is used, wherein the direction of the magnetic field generated by the inner coil in the central magnetic body is consistent with the direction of the magnetic field generated by the outer coil in the central magnetic body. The directions of the magnetic fields generated within the central magnetic body can be the same.

A seventh aspect is the magnetic element according to any one of the first to sixth aspects, characterized by having a detection coil arranged on the outer periphery and/or the peripheral portion of the central magnetic body. The outer periphery of the magnetic body can detect magnetic fields.

An eighth aspect is a magnetic element according to the seventh aspect, characterized by having a dummy coil arranged on the outer periphery of the central magnetic body and/or the outer periphery of the peripheral magnetic body and capable of detecting a magnetic field.

A ninth aspect is the magnetic element according to any one of the first to sixth aspects, characterized by having a detection coil and a dummy coil, the detection coil being arranged on the outer periphery of the central magnetic body and capable of detecting a magnetic field. , the virtual coil is arranged on the outer periphery of the central magnetic body and can detect the magnetic field. This embodiment has the following effects. Sometimes it is not necessary to provide a detection coil or a dummy coil on the outer periphery of the peripheral magnetic body. For example, it may be desirable to limit the acquisition range of the interlinkage flux generated by the eddy current generated by the outer coil and the inner coil by using a magnetic element instead of providing a detection coil and a dummy coil on the peripheral magnetic body. That is, sometimes it is desired to limit the range of the interlinkage magnetic flux that can be obtained by the detection coil and the dummy coil arranged on the outer periphery of the central magnetic body.

A tenth aspect uses an eddy current detector, characterized by having the magnetic element according to any one of the seventh to ninth aspects.

In the eleventh aspect, a polishing device is used, which has: a polishing table, to which a polishing pad for grinding an object to be polished can be attached; a driving part capable of driving the polishing table to rotate; and a holding part, The holding part can hold the object to be polished and press it against the polishing pad; as in the eddy current detector described in the tenth aspect of the patent application, the eddy current detector is arranged inside the polishing table. , the detection coil can detect the eddy current formed in the object to be polished by the inner coil and the outer coil as the grinding table rotates; and an end point detection part, the end point detection part can The detection of the polishing end point indicating the completion of polishing of the object to be polished is based on the detected eddy current.

In a twelfth aspect, the polishing device according to the eleventh aspect is adopted, wherein the end point detection unit determines the polishing rate of the object to be polished based on the detected eddy current, and calculates the polishing rate based on the polishing rate. The expected grinding amount when grinding the object to be grinded, so that the grinding end point can be detected.

A thirteenth aspect is the polishing device according to the twelfth aspect, wherein the end point detection unit compares data on the film thickness obtained from the eddy current with data on the film thickness predicted from the polishing rate. , when the comparison result is larger than the specified value, the data related to the film thickness obtained from the eddy current may not be used.

A fourteenth aspect is the polishing device according to the twelfth aspect or the thirteenth aspect, wherein the end point detection unit is capable of detecting the desired polishing amount and a threshold value related to a film thickness corresponding to the polishing end point. The grinding end point.

In a fifteenth aspect, a polishing method is adopted, which polishing method is a polishing method in which polishing is performed between a polishing pad and an object to be polished that is disposed facing the polishing pad, and is characterized in that the polishing method is held by a polishing table. The step of polishing the pad; the step of rotationally driving the polishing table; the step of rotationally driving the holding portion for holding the object to be polished and pressing it against the polishing pad; arranging the vortex of the tenth mode inside the polishing table. A current-type detector uses the detection coil to detect the eddy current formed in the object to be polished by the inner coil and the outer coil as the grinding table rotates; from the detected eddy current The eddy current detection is a step in which the polishing end point indicates the completion of polishing of the object to be polished.

A sixteenth aspect uses the polishing method according to the fifteenth aspect, characterized in that the intensity of the magnetic field generated by the inner coil and/or the outer coil is changed when the electrical conductivity of the object to be polished changes.

In a seventeenth aspect, the polishing method according to the fifteenth or sixteenth aspect is used, characterized in that a plurality of eddy current detectors according to the tenth aspect are arranged inside the polishing table, and the plurality of eddy current detectors are arranged inside the polishing table. The detection sensitivities of detectors vary from one another.

In the eighteenth aspect, a computer-readable recording medium is used, and the computer-readable recording medium records a program for causing a computer to function as the end point detection means and the control means for controlling the grinding of the object. A grinding device for performing grinding, the grinding device having: a grinding table, to which a grinding pad for grinding the object to be polished can be attached; a driving part capable of driving the grinding table to rotate; and a holding part , the holding part can hold the object to be polished and press it against the polishing pad; as the eddy current detector according to the tenth aspect, the eddy current detector is arranged inside the polishing table and can be The detection coil detects the eddy current formed on the object to be polished by the inner coil and the outer coil as the grinding table rotates, and the end point detection unit can detect the eddy current from the detected eddy current. The eddy current detection indicates the polishing end point indicating the completion of polishing of the object to be polished, and the control means controls the polishing by the polishing device.

A 19th aspect is the polishing device according to any one of the 11th to 14th aspects, characterized in that the polishing device has an optical system, and the optical system passes through a lens provided on the polishing pad. a through hole, which irradiates light to the polished surface of the polished object through an optical fiber, so that the reflected light is collected by the optical fiber; and a film thickness monitoring device of the polished object, where the film thickness monitoring device of the polished object is provided There is an analysis and processing means for analyzing and processing the reflected light received by the optical system, and the analysis and processing means is used to analyze and process the reflected light, and monitor the polishing progress of the thin film formed on the polished surface of the object to be polished, The polishing device is provided with a liquid supply hole on the polishing table that supplies a transparent liquid to a through hole provided on the polishing pad. The liquid supply hole is arranged and formed so that the transparent liquid supplied from the liquid supply hole forms an angle relative to the polishing pad. The flow that travels perpendicularly to the polished surface of the object to be polished fills the through hole, and the optical fiber is configured to allow irradiation light and reflected light to pass through the transparent liquid in the flow portion that travels perpendicularly to the polished surface, and is provided with a discharge The transparent liquid drain hole of the through hole is located behind the movement direction of the polishing table with respect to the liquid supply hole, and is open at the end surface of the through hole opposite to the object to be polished .

A twentieth aspect is the polishing device according to the nineteenth aspect, wherein the midpoint of the line segment connecting the center of the liquid supply hole and the center of the drain hole is located further than the center point of the through hole. In front of the moving direction of the grinding table.

A 21st aspect is the polishing device according to the 19th or 20th aspect, wherein the cross-section of the through-hole is a substantially elliptical hole, and the outer periphery of the end surface surrounds the liquid supply hole and the liquid discharge hole. end face.

A 22nd aspect is the polishing device according to any one of the 19th to 21st aspects, characterized in that a forced draining mechanism is provided, and liquid is forcedly drained from the drain hole by the forced draining mechanism.

In a 23rd aspect, the polishing method according to any one of the 15th to 17th aspects is adopted, characterized by having a light-transmitting liquid nozzle and a device arranged to surround the light-transmitting liquid nozzle at an outer peripheral portion of the light-transmitting liquid nozzle. The light-transmitting liquid receiving part brings the columnar light-transmitting liquid flow from the light-transmitting liquid nozzle into contact with the polished surface of the object to be polished, and receives the light-transmitting liquid flow with the light-transmitting liquid receiving part, The light-transmitting liquid flow in a state in which the light-transmitting liquid in the light-transmitting liquid nozzle communicates with the light-transmitting liquid in the light-transmitting liquid receiving part and is sealed from the outside is passed through the light-transmitting liquid flow through the optical system and is Irradiate light to the polished surface of the polished object, and use the optical system to receive the reflected light reflected by the polished surface of the polished object through the light-transmitting liquid flow, and measure the intensity of the received reflected light from the received reflected light. The film thickness of the surface being ground.

In a 24th aspect, the polishing method according to the 23rd aspect is used, characterized in that the optical system has at least one optical fiber, and the front end of the optical fiber is inserted into the light-transmitting liquid flow, and the light-transmitting liquid flow passes through the optical fiber and the light-transmitting liquid flow. Light is irradiated to the polished surface of the polished object, and the reflected light reflected by the polished surface is collected through the light-transmitting liquid flow and the optical fiber.

In a 25th aspect, the polishing device according to any one of the 11th to 14th aspects and the 19th to 22nd aspects is used, which is characterized in that it has a plurality of processing areas and transfer areas, and the processing areas are implemented A plurality of processing units for light-shielding processing are stored inside in a vertical arrangement. The transport area accommodates a transport machine inside and is disposed between the processing areas. A light-shielding wall is provided between the processing area and the transport area to block light. , and the front of the transportation area is shielded from light by a maintenance door, and the processing unit is connected to the light-shielding wall in a light-shielding state.

A twenty-sixth aspect is the polishing device according to the twenty-fifth aspect, wherein the processing unit is provided with a substrate insertion port having an openable and closable shutter, and the light-shielding wall is provided with a substrate insertion port surrounding the object to be polished The surrounding light-shielding film is provided with an opening in the area where the light-shielding wall is surrounded by the light-shielding film.

A twenty-seventh aspect is a polishing device according to the twenty-fifth or twenty-sixth aspect, characterized in that the processing area is a cleaning area, and the processing of the object to be polished is cleaning of the object to be polished.

In the 28th aspect, the grinding device according to any one of the 11th to 14th aspects, the 19th to 22nd aspects, and the 25th to 27th aspects is used, wherein the grinding device has : a polishing section that polishes the object to be polished; a cleaning section that cleans and dries the object to be polished; a partition wall that separates the polishing section and the cleaning section; and an opening in the partition wall that separates the object. a transport mechanism that transports the polished object from the polishing section to the cleaning section; and a housing that has a side wall and accommodates the polishing section, the cleaning section, and the transport mechanism inside, The cleaning part has: a cleaning means for cleaning the polished object with a cleaning liquid; a drying means for drying the cleaned object to be polished; and a device that can freely move horizontally and vertically between the cleaning means and the drying means. The conveying means for handing over the object to be polished is provided, and the polishing part includes the polishing table, the holding part, the driving part, the eddy current detector, and the end point detection part. Additionally, U.S. Patent No. 5,885,138 is incorporated by reference into this specification in its entirety.

In a 29th aspect, the polishing method according to any one of the 15th to 17th, 23rd and 24th aspects is used, characterized in that in the polishing method using a polishing device, the polishing device has: The polishing part for grinding the object to be polished; the cleaning part for cleaning and drying the object to be polished; the partition wall that separates the grinding part and the cleaning part; and all grinding parts are ground through the opening of the partition wall. a transport unit that transports the object to be polished from the polishing section to the cleaning section; and a housing that has a side wall and accommodates the polishing section, the cleaning section, and the transport unit inside, in the cleaning section , cleaning the polished object with a cleaning liquid, drying the cleaned object, and transferring the polished object horizontally and vertically between the cleaning step and the drying step, and transport the object to be ground.

In the 30th aspect, the grinding device according to any one of the 11th to 14th aspects, the 19th to 22nd aspects, and the 25th to 28th aspects is used, and has the method of applying the polishing device to the object. Polishing the abrasive object, an optical detector that measures the intensity of the reflected light from the object to be abraded, based on the eddy current and the intensity of the reflected light from the object to be abraded measured by the optical detector, The grinding end point indicating the end of said grinding is detected.

In a 31st aspect, the grinding device according to the 30th aspect is adopted, characterized in that it has a viewing window incorporated into the polishing table at a position that can face the object to be polished during polishing, and is located at a lower part of the viewing window. equipped with the optical detector.

In a 32nd aspect, the grinding device according to the 30th aspect is adopted, wherein the grinding table has an opening disposed at a position in the grinding table that can face the object to be polished during grinding, and the An optical detector is disposed at a lower portion of the window, and has a fluid supply portion for supplying a cleaning fluid into the opening.

In the 33rd aspect, the grinding device according to any one of the 11th aspect to the 14th aspect, the 19th aspect to the 22nd aspect, the 25th aspect to the 28th aspect, and the 30th aspect to the 32nd aspect is used. On the basis of the above, the eddy current detector generates a magnetic field on the object to be ground and detects the intensity of the generated magnetic field. In addition, the grinding device has: a second motor for rotationally driving the holding part; a swing arm for holding the holding part; a third motor for swinging the swing arm around a swing center on the swing arm; detecting the drive part (first motor) and the second motor, The detection unit generates a first output based on the current value of one of the third motors and/or the torque command value of the one motor, based on the first output and the eddy current detector. The intensity of the magnetic field is used to detect the polishing end point indicating the end of the polishing.

In the 34th aspect, a program is used for causing a computer to function as the end point detection means and the control means for controlling a grinding device that grinds the object to be ground, and the grinding device has a function for holding the object to be ground. a holding part for the abrasive; a swing arm for holding the holding part; and an arm torque detection part that directly or indirectly detects the arm torque applied to the swing arm, and the end point detection part means is based on the arm The arm torque detected by the torque detection unit detects a polishing end point indicating the completion of the polishing, and the control means controls polishing by the polishing device.

A thirty-fifth aspect uses the program described in the thirty-fourth aspect, wherein the program is updateable.

In a 36th aspect, a polishing device is used, which is characterized in that it has a substrate processing device that polishes a substrate and obtains a signal related to the polishing; and a data processing device connected by the substrate processing device and a communication means, and the data The processing device updates parameters related to the polishing process based on the signal obtained by the substrate processing device. Here, the signal is an analog signal and/or a digital signal.

Here, as polishing parameters, there are, for example, (1) the pressing force on the four regions of the semiconductor wafer, that is, the central part, the inner middle part, the outer middle part, and the peripheral part, (2) the polishing time, (3) The rotational speed of the grinding table and top ring, (4) the threshold used to determine the grinding end point, etc. The update of parameters refers to the update of the above parameters.

In a thirty-seventh aspect, a polishing device is used. In the polishing device according to the thirty-sixth aspect, the signal is obtained by one type of detector or a plurality of detectors of different types. Different types of detectors used in this method include the following detectors. That is, (1) a detector that acquires a measurement signal related to the torque fluctuation of the swing axis motor, (2) an SOPM (optical detector), (3) an eddy current detector, (4) a detector that acquires a signal related to the rotation of the polishing table A detector that measures signals related to changes in the motor current of the motor.

In the 38th mode, a polishing method is adopted, which is characterized by including the steps of connecting a substrate processing device and a data processing device through a communication unit; using the substrate processing device to polish the substrate and obtaining a signal related to polishing; and by The data processing device updates the parameters related to the polishing process based on the signal obtained by the substrate processing device.

In a thirty-ninth aspect, a polishing device is used, which is characterized in that it has a substrate processing device, an intermediate processing device, and a data processing device that polishes a substrate and obtains a signal related to the polishing. The substrate processing device and the intermediate processing device are processed by the third processing device. A communication means is connected. The intermediate processing device and the data processing device are connected by a second communication means. The intermediate processing device generates a data group related to the grinding process based on the signal obtained by the substrate processing device. The data processing device is based on The data set monitors the status of the polishing process of the substrate processing device, and the intermediate processing device or the data processing device detects a polishing end point indicating the end of the polishing based on the data set.

In the 40th mode, a grinding device can be used, characterized in that the signal in the 39th mode is obtained by one detector or a plurality of detectors of different types. Different types of detectors used in this method include the following detectors. That is, (1) a detector that acquires a measurement signal related to the torque fluctuation of the swing axis motor, (2) an SOPM (optical detector), (3) an eddy current detector, (4) a detector that acquires a measurement signal related to the rotation of the polishing table A detector that measures signals related to changes in the motor current of the motor.

In the 41st aspect and the 39th aspect, examples of the data set include the following data set. The detector signal output by the detector and the required control parameters can be used as a data set. That is, the data set can include: the pressing of the semiconductor wafer by the top ring, the current of the swing axis motor, the motor current of the polishing table, the measurement signal of the optical detector, the measurement signal of the eddy current detector, and the top ring on the polishing pad. The location, flow rate/type of slurry and chemical solution, and related calculation data of the above information, etc.

In the 42nd aspect and the 39th aspect, as an example of the transmission method of the data group, there are the following cases. Transmission can be performed using a transmission system that transmits one-dimensional data in parallel or a transmission system that transmits one-dimensional data sequentially. In addition, the above one-dimensional data can be processed into two-dimensional data as a data set.

In the 43rd mode and the 39th mode, a signal with a large change in signal value can be extracted and the polishing parameters can be updated. As a method of updating polishing parameters, for example, there is the following method. By setting a priority proportional coefficient (weighting coefficient) to the target values of both the main detector and the sub-detector, the influence ratio of the main detector and the sub-detector is specified. Extract signals with large changes in signal value to update the priority proportion coefficient. In addition, among the changes in the signal value, there are changes only in a short time and changes in the entire long time. In addition, the change in signal value refers to the time-related differential value of the signal value or the time-related difference, etc.

In the 44th mode, a polishing method is adopted, which is characterized by including: the steps of connecting a substrate processing device and an intermediate processing device that polish the substrate and obtain signals related to the polishing through a first communication means; The step of connecting the intermediate processing device and the data processing device; the step of the intermediate processing device generating a data set related to polishing processing based on the signal obtained by the substrate processing device; the data processing device monitoring based on the data set The step of the polishing processing status of the substrate processing device; and the step of the intermediate processing device or the data processing device detecting a polishing end point indicating the end of the polishing based on the data set.

In the 45th aspect, a polishing method is used for polishing between a polishing pad and an object to be polished arranged opposite to the polishing pad, which is characterized by including: the step of holding the polishing pad by a polishing table; the step of rotationally driving the polishing table; the step of rotationally driving a holding portion for holding the object to be polished and pressing the polishing pad; and arranging the eddy current detector according to the tenth aspect inside the polishing table. The step of; accompanying the rotation of the grinding table, using a detection coil to detect the eddy current formed on the object to be polished through at least one of the first step, the second step, and the third step, the first step being The detection coil is used to detect the eddy current formed on the object to be polished by the inner coil. The aforementioned second step is to detect the eddy current formed on the object to be polished by the outer coil through the detection coil. Eddy current, the aforementioned third step is to use the detection coil to detect the eddy current formed in the object to be ground by both the inner coil and the outer coil; detecting from the detected eddy current The step of the grinding end point indicating the completion of grinding of the object to be ground.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each of the following embodiments, the same or corresponding components are denoted by the same reference numerals, and repeated descriptions may be omitted. In addition, the features shown in each embodiment can also be applied to other embodiments within the scope of not contradicting each other.

FIG. 1 is a plan view showing the overall structure of a substrate processing apparatus according to an embodiment of the present invention. As shown in FIG. 1 , this substrate processing apparatus has a housing part, that is, a substantially rectangular housing 61 in this embodiment. Housing 61 has side walls 700 . The interior of the casing 61 is divided into a loading/unloading part 62, a polishing part 63, and a cleaning part 64 by partition walls 1a and 1b. These loading/unloading portions 62, grinding portions 63, and cleaning portions 64 are independently assembled and exhausted. In addition, the substrate processing apparatus includes a control unit 65 that controls substrate processing operations.

The loading/unloading portion 62 has two or more (four in this embodiment) front loading portions 20 on which wafer cassettes storing a large number of semiconductor wafers (substrates) are placed. These front loading portions 20 are arranged adjacent to the housing 61 and arranged along the width direction (the direction perpendicular to the length direction) of the substrate processing apparatus. The front loader 20 can be equipped with an open cassette, a SMIF (Standard Manufacturing Interface: Standard Manufacturing Interface) cassette, or a FOUP (Front Opening Unified can: front opening wafer cassette). Here, SMIF and FOUP are sealed containers that can ensure an independent environment from the outside space by storing the wafer cassette inside and covering it with a partition wall.

Moreover, in the loading/unloading part 62, the traveling mechanism 21 is laid along the arrangement of the front loading part 20. The traveling mechanism 21 is provided with two transport robots (loaders) 22 that can move in the arrangement direction of the wafer cassettes. The transport robot 22 can access the wafer cassette mounted on the front loader 20 by moving on the traveling mechanism 21 . Each transport robot 22 has two robot arms at the top and bottom. The robot arm on the upper side is used when returning processed semiconductor wafers to the wafer cassette. The robot arm on the lower side is used to take out the semiconductor wafer before processing from the wafer cassette. In this way, the upper and lower manipulators are used separately. In addition, the robot arm on the lower side of the transfer robot 22 can turn the semiconductor wafer over by rotating around its axis.

The loading/unloading section 62 is an area that needs to be kept in the cleanest condition. Therefore, the inside of the loading/unloading unit 62 is normally maintained at a higher pressure than any one of the outside of the substrate processing apparatus, the polishing unit 63 , and the cleaning unit 64 . The polishing section 63 uses slurry as the polishing fluid and is the dirtiest area. Therefore, a negative pressure is formed inside the polishing part 63 , and the pressure is maintained lower than the internal pressure of the cleaning part 64 . The loading/unloading portion 62 is provided with a filter fan unit (not shown) having an air purifying filter such as a HEPA filter, a ULPA filter, or a chemical filter. From the filter fan unit, clean air from which particles, toxic vapors, and toxic gases have been removed is constantly blown out.

The polishing unit 63 is an area for polishing (planarizing) the semiconductor wafer, and includes a first polishing unit 3A, a second polishing unit 3B, a third polishing unit 3C, and a fourth polishing unit 3D. As shown in FIG. 1 , the first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D are arranged along the length direction of the substrate processing apparatus.

As shown in FIG. 1 , the first polishing unit 3A includes a polishing table 30A, a top ring 31A, a polishing liquid supply nozzle 32A, a dresser 33A, and a sprayer 34A. The polishing pad 10 having a polishing surface is attached to the polishing table 30A. The top ring (holding portion) 31A holds the semiconductor wafer, and the semiconductor wafer is polished while being pressed against the polishing pad 10 on the polishing table 30A. The polishing liquid supply nozzle 32A supplies polishing liquid and conditioning liquid (for example, pure water) to the polishing pad 10 . The dresser 33A conditions the polishing surface of the polishing pad 10 . The sprayer 34A makes a mixed fluid of a liquid (for example, pure water) and a gas (for example, nitrogen) or the liquid (for example, pure water) into a mist form and sprays it onto the polishing surface.

Similarly, the second polishing unit 3B includes a polishing table 30B on which the polishing pad 10 is mounted, a top ring 31B, a polishing liquid supply nozzle 32B, a dresser 33B, and a sprayer 34B. The third polishing unit 3C includes a polishing table 30C on which the polishing pad 10 is mounted, a top ring 31C, a polishing liquid supply nozzle 32C, a dresser 33C, and a sprayer 34C. The fourth polishing unit 3D includes a polishing table 30D on which the polishing pad 10 is mounted, a top ring 31D, a polishing liquid supply nozzle 32D, a dresser 33D, and a sprayer 34D.

The first grinding unit 3A, the second grinding unit 3B, the third grinding unit 3C, and the fourth grinding unit 3D have the same structure as each other. Therefore, details of the grinding units will be described below with the first grinding unit 3A as the subject.

FIG. 2 is a perspective view schematically showing the first polishing unit 3A. The top ring 31A is supported by the top ring shaft 111. The polishing pad 10 is attached to the upper surface of the polishing table 30A, and the upper surface of the polishing pad 10 constitutes a polishing surface for polishing the semiconductor wafer 16 . Furthermore, fixed abrasive grains can be used instead of the polishing pad 10 . The top ring 31A and the polishing table 30A are configured to rotate around their axes as shown by arrows. The semiconductor wafer 16 is held on the lower surface of the top ring 31A by vacuum suction. During polishing, the polishing liquid is supplied from the polishing liquid supply nozzle 32A to the polishing surface of the polishing pad 10 , and the semiconductor wafer 16 to be polished is pressed against the polishing surface by the top ring 31A and is polished.

FIG. 3 is a cross-sectional view schematically showing the structure of the top ring 31A. The top ring 31A is connected to the lower end of the top ring shaft 111 via a universal joint 637 . The universal joint 637 is a ball joint that allows the top ring 31A and the top ring shaft 111 to tilt relative to each other and transmits the rotation of the top ring shaft 111 to the top ring 31A. The top ring 31A has a substantially disk-shaped top ring main body 638 and a stop ring 640 arranged at a lower portion of the top ring main body 638 . The top ring main body 638 is made of a material with high strength and rigidity such as metal or ceramic. In addition, the retaining ring 640 is formed of a highly rigid resin material, ceramics, or the like. In addition, the blocking ring 640 and the top ring main body 638 may also be integrally formed.

Housed in a space formed inside the top ring main body 638 and the retaining ring 640 are a circular elastic pad 642 that contacts the semiconductor wafer 16 , an annular pressure piece 643 made of an elastic film, and a holding elastic pad. The generally disc-shaped splint 644 of 642. The upper peripheral end of the elastic pad 642 is held by the splint 644, and four pressure chambers (air bags) P1, P2, P3, and P4 are provided between the elastic pad 642 and the splint 644. The pressure chambers P1, P2, P3, and P4 are formed by the elastic pad 642 and the clamping plate 644. Pressurized fluid such as pressurized air is supplied to the pressure chambers P1, P2, P3, and P4 via fluid paths 651, 652, 653, and 654 respectively, or the pressure chambers P1, P2, P3, and P4 are evacuated. The central pressure chamber P1 is circular, and the other pressure chambers P2, P3, and P4 are annular. These pressure chambers P1, P2, P3, P4 are arranged concentrically.

The internal pressures of the pressure chambers P1, P2, P3, and P4 can be changed independently of each other by the pressure adjustment unit described later, thereby independently adjusting the four regions of the semiconductor wafer 16, that is, the central portion and the inner middle portion. , the outer middle part, and the pressing force of the peripheral part. In addition, by raising and lowering the entire top ring 31A, the retaining ring 640 can be pressed against the polishing pad 10 with a specified pressing force. A pressure chamber P5 is formed between the clamping plate 644 and the top ring body 638, and the pressure chamber P5 is supplied with pressurized fluid via the fluid path 655, or the pressure chamber P5 is evacuated. Thereby, the clamp plate 644 and the elastic pad 642 as a whole can move in the up and down direction.

The peripheral end of the semiconductor wafer 16 is surrounded by a retaining ring 640 to prevent the semiconductor wafer 16 from flying out from the top ring 31A during grinding. An opening (not shown) is formed in a portion of the elastic pad 642 constituting the pressure chamber P3. By creating a vacuum in the pressure chamber P3, the semiconductor wafer 16 is adsorbed and held by the top ring 31A. In addition, by supplying nitrogen gas, dry air, compressed air, etc. to the pressure chamber P3, the semiconductor wafer 16 is released from the top ring 31A.

FIG. 4 is a cross-sectional view schematically showing another structural example of the top ring 31A. In this example, the elastic pad 642 is installed on the lower surface of the top ring body 638 without providing a clamping plate. In addition, the pressure chamber P5 between the clamping plate and the top ring body 638 is not provided. Instead, an elastic bag 646 is disposed between the blocking ring 640 and the top ring body 638, and a pressure chamber P6 is formed inside the elastic bag 646. The retaining ring 640 can move up and down relative to the top ring body 638 . A fluid path 656 is communicated with the pressure chamber P6 so that pressurized fluid such as pressurized air is supplied to the pressure chamber P6 through the fluid path 656 . The internal pressure of the pressure chamber P6 can be adjusted by a pressure adjustment unit described below. Therefore, the pressing force of the retaining ring 640 on the polishing pad 10 can be adjusted independently of the pressing force on the semiconductor wafer 16 . Other structures and operations are the same as those of the top ring shown in Figure 3 . In this embodiment, either type of top ring of Figure 3 or Figure 4 can be used.

FIG. 5 is a cross-sectional view for explaining a mechanism for rotating and swinging the top ring 31A. The top ring shaft (for example, a spline shaft) 111 is rotatably supported on the top ring head 660 . In addition, the top ring shaft 111 is connected to the rotation shaft of the motor M1 via the pulleys 661 and 662 and the belt 663, and the top ring shaft 111 and the top ring 31A are rotated around their axes by the motor M1. The motor M1 is installed on the upper part of the top ring head 660 . In addition, the top ring head 660 and the top ring shaft 111 are connected by an air cylinder 665 as a vertical drive source. The top ring shaft 111 and the top ring 31A move up and down integrally by the air (compressed gas) supplied to the cylinder 665 . In addition, a mechanism including a ball screw and a servo motor may be used as a vertical drive source instead of the air cylinder 665 .

The top ring head 660 is rotatably supported on the support shaft 667 via a bearing 672 . This support shaft 667 is a fixed shaft and has a non-rotating structure. The top ring head 660 is provided with a motor M2, and the relative position of the top ring head 660 and the motor M2 is fixed. The rotation shaft of the motor M2 is connected to the support shaft 667 via a rotation transmission mechanism (gear, etc.) not shown. By rotating the motor M2, the top ring head 660 is allowed to swing (swing) around the support shaft 667. Therefore, by the swinging motion of the top ring head 660, the top ring 31A supported at the front end thereof moves between the polishing position above the polishing table 30A and the transport position on the side of the polishing table 30A. In addition, in this embodiment, the swing mechanism which swings the top ring 31A is comprised by the motor M2.

A through hole (not shown) extending along the length direction of the top ring shaft 111 is formed inside the top ring shaft 111 . The fluid paths 651, 652, 653, 654, 655, and 656 of the top ring 31A are connected to the rotary joint 669 provided at the upper end of the top ring shaft 111 through the through hole. Fluids such as pressurized gas (clean air) and nitrogen are supplied to the top ring 31A via the rotary joint 669 , and the gas is evacuated from the top ring 31A. The rotary joint 669 is connected to a plurality of fluid tubes 670 that communicate with the fluid paths 651 , 652 , 653 , 654 , 655 , and 656 (see FIGS. 3 and 4 ), and these fluid tubes 670 are connected to the pressure adjusting portion 675 . In addition, the fluid pipe 671 for supplying pressurized air to the cylinder 665 is also connected to the pressure adjusting portion 675 .

The pressure adjustment unit 675 includes an electric regulator that adjusts the pressure of the fluid supplied to the top ring 31A, pipes connected to the fluid pipes 670 and 671 , pneumatic valves provided in these pipes, and an operating source constituting the pneumatic valves. An electric regulator that adjusts the pressure of the air, an ejector that creates a vacuum in the top ring 31A, and the like, the above-mentioned structures are combined to form one block (unit). The pressure adjustment part 675 is fixed on the upper part of the top ring head 660 . The pressure of the pressurized gas supplied to the pressure chambers P1, P2, P3, P4, and P5 (see FIG. 3 ) of the top ring 31A and the pressurized air supplied to the cylinder 665 is adjusted by the electric regulator of the pressure adjusting unit 675 . Similarly, the ejector of the pressure adjustment portion 675 creates a vacuum in the pressure chambers P1, P2, P3, and P4 of the top ring 31A and in the pressure chamber P5 between the clamping plate 644 and the top ring body 638.

In this way, since the electric regulator and the valve as the pressure adjusting device are arranged near the top ring 31A, the controllability of the pressure in the top ring 31A is improved. More specifically, since the distance between the electric regulator and the pressure chambers P1, P2, P3, P4, and P5 is close, the responsiveness to the pressure change command from the control unit 65 is improved. Similarly, since the ejector as a vacuum source is also provided near the top ring 31A, the responsiveness when creating a vacuum in the top ring 31A is improved. In addition, the back surface of the pressure adjusting portion 675 can be used as a mounting base for electrical equipment, and a conventionally required mounting frame can be eliminated.

The top ring head 660, the top ring 31A, the pressure adjustment part 675, the top ring shaft 111, the motor M1, the motor M2, and the cylinder 665 constitute a module (hereinafter referred to as the top ring assembly). That is, the top ring shaft 111, the motor M1, the motor M2, the pressure adjustment part 675, and the air cylinder 665 are installed on the top ring head 660. The top ring head 660 is detachable from the support shaft 667 . Therefore, by separating the top ring head 660 from the support shaft 667, the top ring assembly can be detached from the substrate processing apparatus. With the above-mentioned structure, the maintainability of the support shaft 667, the top ring head 660, etc. can be improved. For example, when abnormal noise occurs from the bearing 672 , the bearing 672 can be easily replaced. In addition, when the motor M2 or the rotation transmission mechanism (reducer) is replaced, there is no need to disassemble adjacent equipment.

FIG. 6 is a cross-sectional view schematically showing the internal structure of the polishing table 30A. As shown in FIG. 6 , a detector 676 for detecting the state of the film of the semiconductor wafer 16 is embedded in the polishing table 30A. In this example, an eddy current type detector is used as detector 676 . The signal from the detector 676 is sent to the control unit 65 so that a monitoring signal indicating the film thickness is generated by the control unit 65 . The value of the monitoring signal (and therefore the detector signal) does not represent the film thickness itself, but the value of the monitoring signal changes according to the film thickness. Therefore, the monitoring signal is a signal that can indicate the film thickness of the semiconductor wafer 16 .

The control part 65 determines the internal pressure of each pressure chamber P1, P2, P3, P4 based on the monitoring signal, and outputs an instruction to the pressure adjustment part 675, so that the determined internal pressure is formed in each pressure chamber P1, P2, P3, P4. The control part 65 functions as a pressure control part which operates the internal pressure of each pressure chamber P1, P2, P3, P4 based on a monitoring signal, and as an end point detection part which detects the polishing end point.

Like the first polishing unit 3A, the detector 676 is also provided on the polishing tables of the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D. The control unit 65 generates a monitoring signal from the signal sent from the detector 676 of each polishing unit 3A to 3D, and monitors the progress of polishing of the semiconductor wafer in each polishing unit 3A to 3D. When a plurality of semiconductor wafers are polished by the polishing units 3A to 3D, the control unit 5 monitors monitoring signals indicating the film thickness of the semiconductor wafers during polishing, and controls the pressing force of the top rings 31A to 31D based on these monitoring signals. The grinding time in the grinding units 3A to 3D is made approximately the same. In this way, by adjusting the pressing force of the top rings 31A to 31D during grinding based on the monitoring signal, the grinding time in the grinding units 3A to 3D can be averaged.

The semiconductor crystal may be continuously ground using any one of the first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D, or a plurality of polishing units selected in advance from these polishing units 3A to 3D. Circle 16. For example, the semiconductor wafer 16 may be polished in the order of the first polishing unit 3A → the second polishing unit 3B, or the semiconductor wafer 16 may be polished in the order of the third polishing unit 3C → the fourth polishing unit 3D. In addition, the semiconductor wafer 16 may be polished in the order of the first polishing unit 3A → the second polishing unit 3B → the third polishing unit 3C → the fourth polishing unit 3D. In any case, by averaging the grinding times of all the grinding units 3A to 3D, the output can be improved.

The eddy current detector is suitable for use when the film of the semiconductor wafer is a metal film. When the film of the semiconductor wafer is a translucent film such as an oxide film, an optical detector can be used as the detector 676 . Alternatively, a microwave detector may be used as the detector 676. Microwave detectors can be used for both metallic and non-metallic films. Hereinafter, an example of an optical detector and a microwave detector will be described.

FIG. 7 is a schematic diagram showing a polishing table equipped with an optical detector. As shown in FIG. 7 , an optical detector 676 that detects the state of the film of the semiconductor wafer 16 is embedded in the polishing table 30A. The detector 676 irradiates light to the semiconductor wafer 16 and detects the state of the film (film thickness, etc.) of the semiconductor wafer 16 from the intensity of the reflected light from the semiconductor wafer 16 (reflection intensity or reflectance).

In addition, the polishing pad 10 is provided with a light-transmitting portion 677 for transmitting light from the detector 676 . The light-transmitting portion 677 is made of a material with high transmittance, such as non-foaming polyurethane. Alternatively, the light-transmitting portion 677 may be formed by providing a through hole in the polishing pad 10 and flowing a transparent liquid from below while the through hole is blocked by the semiconductor wafer 16 . The light-transmitting portion 677 is disposed at the center of the semiconductor wafer 16 held by the top ring 31A.

As shown in FIG. 7 , the detector 676 has: a light source 678a; a light-emitting optical fiber 678b as a light-emitting part that irradiates the light from the light source 678a to the polished surface of the semiconductor wafer 16; and a receiver that receives reflected light from the polished surface. The light-collecting optical fiber 678c of the optical part; a spectrometer unit 678d internally equipped with a spectroscope that splits the light received by the light-collecting optical fiber 678c and a plurality of light-collecting elements that stores the light splitted by the spectroscope as electrical information; control The operation control unit 678e controls the lighting and extinguishing of the light source 678a and the time when the light collecting element in the spectroscope unit 678d starts reading; and the power supply 678f that supplies power to the operation control unit 678e. In addition, power is supplied to the light source 678a and the spectroscope unit 678d via the operation control unit 678e.

The light-emitting end of the light-emitting optical fiber 678b and the light-receiving end of the light-collecting optical fiber 678c are configured to be substantially perpendicular to the surface to be polished of the semiconductor wafer 16. As the light collecting element in the spectroscope unit 678d, for example, a 128-element photodiode array can be used. The spectroscope unit 678d is connected to the operation control unit 678e. Information from the light-collecting element in the spectroscope unit 678d is sent to the action control unit 678e, and spectral data of the reflected light is generated based on the information. That is, the operation control unit 678e reads the electrical information stored in the light-collecting element to generate spectral data of the reflected light. This spectral data represents the intensity of reflected light decomposed according to wavelength, and changes depending on the film thickness.

The operation control unit 678e is connected to the control unit 65 described above. In this way, the spectral data generated by the operation control unit 678e is sent to the control unit 65. In the control unit 65, based on the spectrum data received from the operation control unit 678e, a characteristic value related to the film thickness of the semiconductor wafer 16 is calculated and used as a monitoring signal.

FIG. 8 is a schematic diagram showing a polishing table equipped with a microwave detector. The detector 676 includes an antenna 680a that irradiates the polished surface of the semiconductor wafer 16 with microwaves, a detector body 680b that supplies microwaves to the antenna 680a, and a waveguide 681 that connects the antenna 680a and the detector body 680b. The antenna 680a is embedded in the polishing table 30A and is arranged to face the center position of the semiconductor wafer 16 held by the top ring 31A.

The detector main body 680b has a microwave source 680c that generates microwaves and supplies the microwaves to the antenna 680a; and a device that separates the microwaves (incident waves) generated by the microwave source 680c from the microwaves (reflected waves) reflected from the surface of the semiconductor wafer 16. splitter 680d; and a detection unit 680e that receives the reflected wave separated by the splitter 680d and detects the amplitude and phase of the reflected wave. In addition, as the splitter 680d, a directional coupler is suitably used.

The antenna 680a is connected to the splitter 680d via the waveguide 681. The microwave source 680c is connected to the splitter 680d, and the microwave generated by the microwave source 680c is supplied to the antenna 680a via the splitter 680d and the waveguide 681. The microwaves are irradiated from the antenna 680 a to the semiconductor wafer 16 , and penetrate (penetrate) the polishing pad 10 to reach the semiconductor wafer 16 . The reflected wave from the semiconductor wafer 16 passes through the polishing pad 10 again and is received by the antenna 680a.

The reflected wave is sent from the antenna 680a to the splitter 680d through the waveguide 681, and the incident wave and the reflected wave are separated by the splitter 680d. The reflected wave separated by the separator 680d is sent to the detection part 680e. The detection unit 680e detects the amplitude and phase of the reflected wave. The amplitude of the reflected wave is detected as electric power (dbm or W) or voltage (V), and the phase of the reflected wave is detected by a phase meter (not shown) built in the detection unit 680e. The amplitude and phase of the reflected wave detected by the detection unit 680e are sent to the control unit 65, where the film thickness of the metal film, non-metal film, etc. of the semiconductor wafer 16 is analyzed based on the amplitude and phase of the reflected wave. The value analyzed is monitored by the control unit 65 as a monitoring signal.

FIG. 9 is a perspective view showing a trimmer 33A usable as an embodiment of the present invention. As shown in FIG. 9 , the dresser 33A includes: a dresser arm 685; a dresser member 686 rotatably mounted on the front end of the dresser arm 685; a swing shaft 688 connected to the other end of the dresser arm 685; and a swing shaft as a swing shaft. 688 serves as a motor 689 of the driving mechanism that swings (swings) the dresser arm 685 around the center. The trimming member 686 has a circular trimming surface, and hard particles are fixed on the trimming surface. Examples of the hard particles include diamond particles, ceramic particles, and the like. A motor (not shown) is built into the trimmer arm 685, and the trimming member 686 is rotated by this motor. The swing shaft 688 is connected to a lifting mechanism (not shown), and the lifting mechanism lowers the dresser arm 685 so that the dressing member 686 presses the polishing surface of the polishing pad 10 .

FIG. 10( a ) is a perspective view showing the sprayer 34A. The sprayer 34A has an arm 690 having one or a plurality of spray holes in the lower part, a fluid flow path 691 connected to the arm 690, and a swing shaft 694 that supports the arm 690. FIG. 10( b ) is a schematic diagram showing the lower part of the arm 690 . In the example shown in FIG. 10( b ), a plurality of injection holes 690 a are formed at equal intervals in the lower part of the arm 690 . The fluid flow path 691 can be configured by a hose, a pipe, or a combination thereof.

FIG. 11( a ) is a side view showing the internal structure of the nebulizer 34A, and FIG. 11( b ) is a plan view showing the nebulizer 34A. The open end of the fluid flow path 691 is connected to a fluid supply pipe (not shown), and fluid is supplied from the fluid supply pipe to the fluid flow path 691 . Examples of the fluid used include a liquid (for example, pure water), a mixed fluid of a liquid and a gas (for example, a mixed fluid of pure water and nitrogen), and the like. The fluid flow path 691 communicates with the injection hole 690 a of the arm 690 , and the fluid becomes mist and is injected from the injection hole 690 a to the polishing surface of the polishing pad 10 .

As shown by the dotted lines in FIG. 10( a ) and FIG. 11( b ), the arm 690 is pivotable between the cleaning position and the retreat position with the swing axis 694 as the center. The movable angle of the arm 690 is approximately 90°. Generally, as shown in FIG. 1 , the arm 690 is located in the cleaning position and is arranged along the radial direction of the polishing surface of the polishing pad 10 . During maintenance such as replacement of the polishing pad 10, the arm 690 is manually moved to the retreat position. Therefore, there is no need to disassemble the arm 690 during maintenance, and maintainability can be improved. Alternatively, the rotation mechanism may be connected to the swing shaft 694 and the arm 690 may be rotated by the rotation mechanism.

As shown in FIG. 11( b ), two reinforcing members 696 and 696 having different shapes are provided on both sides of the arm 690 . By providing these reinforcing members 696 and 696, when the arm 690 performs a swing motion between the cleaning position and the retreat position, the axis center of the arm 690 will not vibrate significantly, and the atomization motion can be effectively performed. In addition, the sprayer 34A has a lever 695 for fixing the swing position of the arm 690 (the angular range in which the arm 690 can swing). That is, by using the operation lever 695, the angle at which the arm 690 can rotate can be adjusted according to conditions. When the lever 695 is rotated, the arm 690 can rotate freely, and the arm 690 can be manually moved between the cleaning position and the retreat position. Furthermore, when the lever 695 is tightened, the position of the arm 690 is fixed in either the cleaning position or the retracted position.

The arm 690 of the sprayer may also be configured to be foldable. Specifically, the arm 690 may be composed of at least two arm members connected by a joint. In this case, the angle formed by the arm members when folded is not less than 1° and not more than 45°, preferably not less than 5° and not more than 30°. When the angle between the arm components is greater than 45°, the arm 690 occupies a large space. When it is less than 1°, the width of the thin arm 690 must be reduced, and the mechanical strength will be reduced. In this example, the arm 690 may be configured not to rotate about the swing axis 694 . During maintenance such as replacement of the polishing pad 10, the folding arm 690 prevents the sprayer from interfering with the maintenance work. As another modification, the arm 690 of the sprayer can be made telescopic. In this example, by shortening the arm 690 during maintenance, the sprayer is therefore not in the way.

The purpose of providing the sprayer 34A is to flush the grinding debris, abrasive grains, etc. remaining on the polishing surface of the polishing pad 10 with high-pressure fluid. By using the fluid pressure of the sprayer 34A to purify the polishing surface and the mechanical contact of the dresser 33A to dress the polishing surface, better dressing, that is, regeneration of the polishing surface can be achieved. Usually, after dressing with a contact type dresser (diamond dresser, etc.), the polished surface is often regenerated with a sprayer.

Next, a conveyance mechanism for conveying a semiconductor wafer will be described with reference to FIG. 1 . The conveyance mechanism includes a lifter 11, a first linear conveyor 66, a swing conveyor 12, a second linear conveyor 67, and a buffer table 180.

The lifter 11 receives the semiconductor wafer from the transfer robot 22 . The first linear conveyor 66 conveys the semiconductor wafer received from the elevator 11 between the first conveyance position TP1 , the second conveyance position TP2 , the third conveyance position TP3 and the fourth conveyance position TP4 . The first polishing unit 3A and the second polishing unit 3B receive and polish the semiconductor wafer from the first linear conveyor 66 . The first polishing unit 3A and the second polishing unit 3B deliver the polished semiconductor wafer to the first linear conveyor 66 .

The swing transfer device 12 transfers semiconductor wafers between the first linear transfer device 66 and the second linear transfer device 67 . The second linear conveyor 67 conveys the semiconductor wafer received from the swing conveyor 12 between the fifth conveyance position TP5, the sixth conveyance position TP6, and the seventh conveyance position TP7. The third grinding unit 3C and the fourth grinding unit 3D receive and grind the semiconductor wafer from the second linear conveyor 67 . The third polishing unit 3C and the fourth polishing unit 3D deliver the polished semiconductor wafer to the second linear conveyor 67 . The semiconductor wafer that has been polished by the polishing unit 3 is placed on the temporary storage table 180 by the swing transfer device 12 .

FIG. 12( a ) is a plan view showing the cleaning unit 64 , and FIG. 12( b ) is a side view showing the cleaning unit 64 . As shown in FIGS. 12( a ) and 12 ( b ), the cleaning unit 64 is divided into a first cleaning chamber 190 , a first transfer chamber 191 , a second cleaning chamber 192 , a second transfer chamber 193 , and a drying chamber 194 . An upper primary cleaning module 201A and a lower primary cleaning module 201B are arranged in the first cleaning chamber 190 and are arranged in a longitudinal direction. The upper primary cleaning module 201A is arranged above the lower primary cleaning module 201B. Similarly, an upper secondary cleaning module 202A and a lower secondary cleaning module 202B arranged in a longitudinal direction are arranged in the second cleaning chamber 192 . The upper secondary cleaning module 202A is disposed above the lower secondary cleaning module 202B. The primary and secondary cleaning modules 201A, 201B, 202A, and 202B are cleaning machines that use cleaning fluid to clean semiconductor wafers. These primary and secondary cleaning modules 201A, 201B, 202A, and 202B are arranged in the vertical direction, so they have the advantage of occupying a small area.

A temporary storage stage 203 for semiconductor wafers is provided between the upper secondary cleaning element 202A and the lower secondary cleaning element 202B. In the drying chamber 194, an upper drying module 205A and a lower drying module 205B are arranged in a longitudinal direction. These upper drying modules 205A and lower drying modules 205B are isolated from each other. Filter fan units 207 and 207 for supplying clean air into the drying modules 205A and 205B are provided above the upper drying module 205A and the lower drying module 205B, respectively. The upper primary cleaning module 201A, the lower primary cleaning module 201B, the upper secondary cleaning module 202A, the lower secondary cleaning module 202B, the temporary storage table 203, the upper drying module 205A, and the lower drying module 205B It is fixed to the frame (not shown) via bolts etc.

The first transportation robot 209 that can move up and down is arranged in the first transportation room 191 , and the second transportation robot 210 that can move up and down is arranged in the second transportation room 193 . The first transportation robot 209 and the second transportation robot 210 are respectively movably supported by support shafts 211 and 212 extending in the longitudinal direction. The first conveyance robot 209 and the second conveyance robot 210 have drive mechanisms such as motors inside, and can move vertically along the support shafts 211 and 212 . The first conveyance robot 209 has two upper and lower levels of robot arms like the conveyance robot 22 . As shown by the dotted line in FIG. 12( a ), the lower manipulator of the first transfer robot 209 is disposed at a position where the buffer table 180 can be accessed. When the lower robot arm of the first transfer robot 209 accesses the buffer table 180 , a shutter (not shown) provided in the partition wall 1 b is opened.

The first transfer robot 209 operates to store the temporary storage table 180, the upper primary cleaning module 201A, the lower primary cleaning module 201B, the temporary storage table 203, the upper secondary cleaning module 202A, and the lower secondary cleaning element 202B. The semiconductor wafer 16 is transported therebetween. The first transfer robot 209 uses the lower robot arm when transporting the semiconductor wafer before cleaning (semiconductor wafer to which slurry is attached), and uses the upper robot arm when transporting the semiconductor wafer after cleaning. The second transport robot 210 operates to transport the semiconductor wafer 16 between the upper secondary cleaning module 202A, the lower secondary cleaning module 202B, the buffer table 203, the upper drying element 205A, and the lower drying element 205B. Since the second transport robot 210 only transports the cleaned semiconductor wafer, it only has one robot arm. The transfer robot 22 shown in FIG. 1 uses its upper robot arm to take out the semiconductor wafer from the upper drying element 205A or the lower drying element 205B, and returns the semiconductor wafer to the wafer cassette. When the upper robot arm of the transportation robot 22 accesses the drying elements 205A and 205B, the shutter (not shown) provided in the partition wall 1a is opened.

Since the cleaning unit 64 has two primary cleaning modules and two secondary cleaning modules, it can constitute a plurality of cleaning lines for cleaning a plurality of semiconductor wafers in parallel. The "cleaning line" refers to a moving path when a semiconductor wafer is cleaned by a plurality of cleaning elements inside the cleaning unit 64 . For example, as shown in FIG. 13 , the first transportation robot 209 , the upper primary cleaning module 201A, the first transportation robot 209 , the upper secondary cleaning element 202A, the second transportation robot 210 , and then the upper drying element 205A A semiconductor wafer is transported in this order (see cleaning line 1). In parallel with this, the first transport robot 209, the lower primary cleaning module 201B, the first transport robot 209, and the lower secondary cleaning element 202B, The second transport robot 210 transports other semiconductor wafers in this order, and then the lower drying element 205B (see cleaning line 2). As described above, using two parallel cleaning lines, a plurality of (typically two) semiconductor wafers can be cleaned and dried almost simultaneously.

Next, the structures of the upper drying element 205A and the lower drying element 205B will be described. The upper drying element 205A and the lower drying element 205B are dryers that perform rotational movement drying. The upper drying element 205A and the lower drying element 205B have the same structure, so the upper drying element 205A will be described below. FIG. 14 is a longitudinal sectional view showing the upper drying module 205A, and FIG. 15 is a plan view showing the upper drying module 205A. The upper drying element 205A has a base 401 and four cylindrical substrate support members 402 supported by the base 401 . The base 401 is fixed to the upper end of the rotation shaft 406, and the rotation shaft 406 is rotatably supported by the bearing 405. The bearing 405 is fixed to the inner peripheral surface of the cylindrical body 407 extending parallel to the rotation axis 406 . The lower end of the cylinder 407 is mounted on the stand 409, and its position is fixed. The rotating shaft 406 is connected to the motor 415 via the pulleys 411 and 412 and the belt 414. By driving the motor 415, the base 401 is rotated around its axis.

A rotating cover 450 is fixed to the upper surface of the base 401 . In addition, FIG. 14 shows a longitudinal sectional view of the rotation cover 450. The rotation cover 450 is disposed to surround the entire circumference of the semiconductor wafer 16 . The longitudinal cross-sectional shape of the rotary cover 450 is inclined radially inward. In addition, the longitudinal cross-sectional view of the rotation cover 450 is composed of a smooth curve. The upper end of the rotating cover 450 is close to the semiconductor wafer 16 , and the inner diameter of the upper end of the rotating cover 450 is set to be slightly larger than the diameter of the semiconductor wafer 16 . In addition, a cutout 450 a extending along the shape of the outer peripheral surface of the substrate support member 402 is formed at the upper end of the rotation cover 450 corresponding to each substrate support member 402 . A liquid discharge hole 451 extending obliquely is formed on the bottom surface of the rotating cover 450 .

A front nozzle 454 is arranged above the semiconductor wafer 16 , and the front nozzle 454 supplies pure water to the surface (front surface) of the semiconductor wafer 16 as a cleaning liquid. Front nozzle 454 is disposed toward the center of semiconductor wafer 16 . The front nozzle 454 is connected to a pure water supply source (cleaning liquid supply source) (not shown), and pure water is supplied to the center of the surface of the semiconductor wafer 16 through the front nozzle 454 . Examples of the cleaning liquid include chemical liquids in addition to pure water. In addition, two nozzles 460 and 461 for performing rotational movement drying are arranged in parallel above the semiconductor wafer 16 . The nozzle 460 supplies IPA vapor (a mixture of isopropyl alcohol and N2 gas) to the surface of the semiconductor wafer 16 , and the nozzle 461 supplies pure water to prevent the surface of the semiconductor wafer 16 from drying. These nozzles 460 and 461 are configured to be movable in the radial direction of the semiconductor wafer 16 .

Arranged inside the rotating shaft 406 are a rear nozzle 463 connected to a cleaning liquid supply source 465 and a gas nozzle 464 connected to a dry gas supply source 466 . Pure water is stored in the cleaning liquid supply source 465 as the cleaning liquid, and the pure water is supplied to the back surface of the semiconductor wafer 16 through the rear nozzle 463 . In addition, the dry gas supply source 466 stores N2 gas, dry air, or the like as dry gas, and the dry gas is supplied to the back surface of the semiconductor wafer 16 through the gas nozzle 464 .

Next, the supply of pure water from the front nozzle 454 is stopped, the front nozzle 454 is moved to a designated standby position away from the semiconductor wafer 16 , and the two nozzles 460 and 461 are moved above the semiconductor wafer 16 Location. Then, while the semiconductor wafer 16 is rotated at a low speed of 30 to 150 min-1, IPA vapor is supplied from the nozzle 460 to the surface of the semiconductor wafer 16, and pure water is supplied from the nozzle 461 to the surface of the semiconductor wafer 16. At this time, pure water is also supplied from the rear nozzle 463 to the back surface of the semiconductor wafer 16 . Then, the two nozzles 460 and 461 are simultaneously moved in the radial direction of the semiconductor wafer 16 . Thereby, the surface (upper surface) of the semiconductor wafer 16 is dried.

Thereafter, the two nozzles 460 and 461 are moved to a designated standby position, and the supply of pure water from the rear nozzle 463 is stopped. Then, the semiconductor wafer 16 is rotated at a high speed at a speed of 1000 to 1500 min -1 to shake off the pure water attached to the back surface of the semiconductor wafer 16 . At this time, the dry gas is blown from the gas nozzle 464 to the back surface of the semiconductor wafer 16 . In this way, the back surface of the semiconductor wafer 16 is dried. The dried semiconductor wafer 16 is taken out from the drying element 205A by the transport robot 22 shown in FIG. 1 and returned to the wafer cassette. In this way, the semiconductor wafer is subjected to a series of processes including grinding, cleaning and drying. According to the drying element 205A configured as described above, both surfaces of the semiconductor wafer 16 can be dried quickly and effectively, and the end point of the drying process can be accurately controlled. Therefore, the processing time for the drying process does not become a speed-limiting process of the entire cleaning process. In addition, the processing time in the plurality of cleaning lines formed in the cleaning unit 4 can be averaged, and the throughput of the entire process can be improved.

According to this embodiment, the semiconductor wafer is in a dry state when the semiconductor wafer is loaded into the polishing apparatus (before loading). After polishing and cleaning are completed, the semiconductor wafer is in a dry state before unloading and is unloaded from the substrate cassette. The dry semiconductor crystal can be put into the cassette from the grinding device and taken out. That is, dry entry/dry removal is possible.

The semiconductor wafer placed on the buffer table 180 is transported to the first cleaning chamber 190 or the second cleaning chamber 192 via the first transport chamber 191 . The semiconductor wafer is cleaned in the first cleaning chamber 190 or the second cleaning chamber 192 . The semiconductor wafer that has been cleaned in the first cleaning chamber 190 or the second cleaning chamber 192 is transported to the drying chamber 194 through the second transport chamber 193 . The semiconductor wafer is dried in the drying chamber 194 . The dried semiconductor wafer is taken out from the drying chamber 194 by the transportation robot 22 and returned to the cassette.

FIG. 16 is a schematic diagram showing the overall structure of a polishing unit (polishing device) according to an embodiment of the present invention. As shown in FIG. 16 , the polishing device includes a polishing table 30A and a top ring 31A (holding portion) that holds a substrate such as a semiconductor wafer that is a polishing object and presses the substrate against the polishing surface of the polishing table.

The first polishing unit 3A is a polishing unit for polishing between the polishing pad 10 and the semiconductor wafer 16 arranged to face the polishing pad 10 . The first polishing unit 3A includes a polishing table 30A for holding the polishing pad 10 and a top ring 31A for holding the semiconductor wafer 16 . The first polishing unit 3A has a swing arm 110 for holding the top ring 31A, a swing shaft motor 14 for swinging the swing arm 110, and a driver 18 that supplies driving power to the swing shaft motor 14. Furthermore, the first polishing unit 3A has an arm torque detection unit 26 that detects the arm torque applied to the swing arm 110 and detects a polishing end point indicating the end of polishing based on the arm torque 26 a detected by the arm torque detection unit 26 . The end point detection part 28. The end point detection unit 28 detects the polishing end point indicating the end of polishing using at least one of the output of the arm torque detection unit 26 and the output of the current detection unit 810 described below.

This embodiment will be described with reference to FIGS. 16 to 48 . By retaining the top ring at the end of the swing arm, the precision of the polishing end point detection can be improved. In this embodiment, a method based on eddy currents, a method based on arm torque, and a method of detecting and utilizing the driving load of the driving unit that rotates the polishing table or the top ring can be used as the polishing end point detection means. In this embodiment, in the manner in which the top ring is held at the end of the swing arm, the polishing end point is mainly detected based on eddy current. However, the polishing end point can also be detected based on the eddy current arm torque, or the polishing end point can be detected. The driving load of the driving unit that drives the table or the top ring to rotate is detected to detect the polishing end point.

The holding part, the swing arm, the arm driving part, and the end point detection part constitute a group, and groups with the same structure are respectively provided in the first grinding unit 3A, the second grinding unit 3B, the third grinding unit 3C, and the fourth grinding unit 3D.

The grinding table 30A is connected to the motor M3 (refer to FIG. 2 ) that is a drive unit disposed below the table axis 102 and is rotatable around the table axis 102 . The polishing pad 10 is attached to the upper surface of the polishing table 30A, and the surface 101 of the polishing pad 10 constitutes a polishing surface for polishing the semiconductor wafer 16 . A polishing liquid supply nozzle (not shown) is provided above the polishing table 30A, and the polishing liquid Q is supplied to the polishing pad 10 on the polishing table 30A through the polishing liquid supply nozzle. As shown in FIG. 16 , an eddy current detector 50 that generates an eddy current in the semiconductor wafer 16 and detects the polishing end point is embedded in the polishing table 30A.

The top ring 31A is composed of a top ring main body 24 that presses the semiconductor wafer 16 against the polishing surface 101 and a stop ring 23 that holds the outer peripheral edge of the semiconductor wafer 16 so that the semiconductor wafer 16 does not fly out from the top ring.

The top ring 31A is connected to the top ring shaft 111. The top ring shaft 111 moves up and down relative to the swing arm 110 by an up and down movement mechanism (not shown). By the up and down movement of the top ring shaft 111, the entire top ring 31A is raised, lowered and positioned relative to the swing arm 110.

In addition, the top ring shaft 111 is connected to the rotating cylinder 112 via a key (not shown). This rotating drum 112 has a timing pulley 113 on its outer peripheral portion. A top ring motor 114 is fixed to the swing arm 110 . The timing pulley 113 is connected to the timing pulley 116 provided in the top ring motor 114 via a timing belt 115 . When the top ring motor 114 rotates, the rotating drum 112 and the top ring shaft 111 are integrally rotated via the timing pulley 116 , the timing belt 115 , and the timing pulley 113 , thereby rotating the top ring 31A.

The swing arm 110 is connected to the rotation shaft of the swing shaft motor 14 . The swing shaft motor 14 is fixed to the swing arm shaft 117 . Therefore, the swing arm 110 is supported rotatably with respect to the swing arm shaft 117 .

The top ring 31A can hold a substrate such as the semiconductor wafer 16 on its lower surface. The swing arm 110 is swingable around the swing arm axis 117 . The top ring 31A holding the semiconductor wafer 16 on its lower surface moves from the receiving position of the semiconductor wafer 16 to above the polishing table 30A by the rotation of the swing arm 110 . Then, the top ring 31A is lowered to press the semiconductor wafer 16 against the surface (polishing surface) 101 of the polishing pad 10 . At this time, the top ring 31A and the grinding table 30A are rotated respectively. At the same time, the polishing liquid is supplied to the polishing pad 10 from the polishing liquid supply nozzle provided above the polishing table 30A. In this way, the semiconductor wafer 16 is brought into sliding contact with the polishing surface 101 of the polishing pad 10, and the surface of the semiconductor wafer 16 is polished.

The first polishing unit 3A has a table drive unit (not shown) that drives the polishing table 30A to rotate. The first polishing unit 3A may include a table torque detection unit (not shown) that detects table torque applied to the polishing table 30A. The table torque detection unit can detect the table torque from the current of the table drive unit which is the rotation motor. The end point detection unit 28 may detect the polishing end point indicating the end of polishing only from the eddy current detected by the eddy current detector 50 , or the end point detection unit 28 may take the arm torque 26 a detected by the arm torque detection unit 26 into consideration. , table torque, detects the grinding end point indicating the end of grinding.

Next, the eddy current detector 50 included in the polishing device of the present invention will be described in detail with reference to the drawings. FIG. 17 is a diagram showing the structure of the eddy current type detector 50. FIG. 17(a) is a block diagram showing the structure of the eddy current type detector 50. FIG. 17(b) is an equivalent circuit diagram of the eddy current type detector 50. .

As shown in FIG. 17( a ), the eddy current detector 50 is arranged near the metal film (or conductive film) mf of the detection target, and the AC signal source 52 is connected to its coil. Here, the detection target metal film (or conductive film) mf is, for example, a thin film such as Cu, Al, Au, or W formed on the semiconductor wafer W. The eddy current detector 50 is arranged, for example, about 1.0 to 4.0 mm away from the metal film (or conductive film) of the detection target.

In the eddy current detector, by generating eddy current in the metal film (or conductive film) mf, the oscillation frequency changes. From this frequency change, the frequency pattern and impedance change of the metal film (or conductive film) are detected, and based on the impedance Change the impedance type of the detection metal film (or conductive film). . That is, in the frequency type, in the equivalent circuit shown in FIG. 17(b), when the eddy current I2 changes, when the impedance Z changes and the oscillation frequency of the signal source (variable frequency oscillator) 52 changes, The detection circuit 54 can detect the change in the oscillation frequency and can detect the change in the metal film (or conductive film). In the impedance type, in the equivalent circuit shown in Figure 17(b), when the eddy current I2 changes, when the impedance Z changes and the impedance Z seen from the signal source (fixed frequency oscillator) 52 changes, The detection circuit 54 can detect the change in the impedance Z, and can detect the change in the metal film (or conductive film).

In the impedance type eddy current detector, the signal outputs X, Y, phase, and combined impedance Z are taken out as described later. From the frequency F or the impedance X, Y, etc., the measurement information of the metal film (or conductive film) Cu, Al, Au, W can be obtained. The eddy current detector 50 can be built in a position near the surface inside the polishing table 30A as shown in FIG. Changes in the metal film (or conductive film) are detected through the eddy current of the metal film (or conductive film) on the semiconductor wafer.

The frequency of the eddy current detector can use a single radio wave, a mixed radio wave, an AM modulated radio wave, an FM modulated radio wave, the scan output of a function generator, or multiple oscillation frequency sources. It should be suitable for the type of metal film and choose an oscillation frequency with good sensitivity. , modulation method.

The impedance type eddy current detector will be described in detail below. The AC signal source 52 uses a fixed frequency oscillator of approximately 2 to 30 MHz, such as a crystal oscillator. Furthermore, the current I1 flows to the eddy current detector 50 by the AC voltage supplied from the AC signal source 52 . The current flows to the eddy current detector 50 arranged near the metal film (or conductive film) mf, and the magnetic flux interlinks with the metal film (or conductive film) mf. Mutual inductance M is formed, and eddy current I2 flows in the metal film (or conductive film) mf. Here, R1 is the equivalent impedance including the primary side of the eddy current detector, and L1 is the self-inductance similarly including the primary side of the eddy current detector. On the mf side of the metal film (or conductive film), R2 is the equivalent impedance equivalent to the eddy current loss, and L2 is its self-inductance. It can be seen from the terminals a and b of the AC signal source 52 that the impedance Z on the eddy current detector side changes depending on the size of the eddy current loss formed in the metal film (or conductive film) mf.

18 and 19 are schematic diagrams showing a configuration example of the eddy current detector 50 according to this embodiment. The eddy current detector 50 arranged near the substrate on which the conductive film is formed is composed of a can core 60 and six coils 860, 862, 864, 866, 868, and 870. The can-shaped core 60 as a magnetic material has a bottom portion 61a (bottom magnetic material), a magnetic core portion 61b (central magnetic material) provided in the center of the bottom portion 61a, and a peripheral wall portion 61c ( Peripheral magnetic body). The peripheral wall part 61c is a wall part provided at the peripheral part of the bottom surface part 61a, and surrounds the magnetic core part 61b. In this embodiment, the bottom portion 61a has a circular disk shape, the magnetic core portion 61b has a solid cylindrical shape, and the peripheral wall portion 61c has a cylindrical shape surrounding the bottom portion 61a.

The central coils 860 and 862 among the six coils 860 , 862 , 864 , 866 , 868 , and 870 are excitation coils connected to the AC signal source 52 . The excitation coils 860 and 862 generate eddy currents in the metal film (or conductive film) mf arranged on the nearby semiconductor wafer W by the magnetic field formed by the voltage supplied from the AC signal source 52 . Detection coils 864 and 866 are arranged on the metal film side of the excitation coils 860 and 862 to detect the magnetic field generated by the eddy current formed in the metal film. Virtual coils 868 and 870 are arranged on the opposite side to the detection coils 864 and 866 across the excitation coils 860 and 862 .

The excitation coil 860 is an internal coil arranged on the outer periphery of the magnetic core portion 61b and capable of generating a magnetic field and forming an eddy current in the conductive film. The excitation coil 862 is an external coil arranged on the outer periphery of the peripheral wall portion 61c and capable of generating a magnetic field and forming an eddy current in the conductive film. The detection coil 864 is arranged on the outer periphery of the magnetic core portion 61b and can detect the magnetic field and the eddy current formed in the conductive film. The detection coil 866 is arranged on the outer periphery of the peripheral wall portion 61c and can detect a magnetic field and eddy current formed in the conductive film.

The eddy current detector includes virtual coils 868 and 870 that detect eddy currents formed in the conductive film. The virtual coil 868 is arranged on the outer periphery of the magnetic core portion 61b and can detect a magnetic field. The virtual coil 870 is arranged on the outer periphery of the peripheral wall portion 61c and can detect a magnetic field. In this embodiment, the detection coil and the dummy coil are arranged on the outer periphery of the bottom portion 61a and the peripheral wall portion 61c. However, the detection coil and the dummy coil may be arranged on only one of the outer periphery of the bottom portion 61a and the peripheral wall portion 61c.

The axial direction of the magnetic core portion 61b is orthogonal to the conductive film on the substrate. The detection coils 864 and 866, the excitation coils 860 and 862, and the dummy coils 868 and 870 are arranged at different positions in the axial direction of the magnetic core portion 61b. In the axial direction of 61b, detection coils 864 and 866, excitation coils 860 and 862, and dummy coils 868 and 870 are arranged in this order from a position close to the conductive film on the substrate to a position farther away. Lead wires (not shown) for external connection are respectively led from the detection coils 864 and 866, the excitation coils 860 and 862, and the dummy coils 868 and 870.

FIG. 18 is a cross-sectional view of a plane passing through the central axis 872 of the magnetic core portion 61b. The can-shaped core 60 as a magnetic material has a disk-shaped bottom portion 61a, a cylindrical magnetic core portion 61b provided at the center of the bottom portion 61a, and a cylindrical peripheral wall portion 61c provided around the bottom portion 61a. As an example of the dimensions of the can core 60 , the diameter L1 of the bottom portion 61 a is approximately 1 cm to 5 cm, and the height L2 of the eddy current detector 50 is approximately 1 cm to 5 cm. The outer diameter of the peripheral wall portion 61 c has a cylindrical shape that is uniform in the height direction in FIG. 18 , but may also have a tapered shape (tapered shape) that tapers away from the bottom portion 61 a, that is, toward the tip.

The wires used in the detection coils 864 and 866, the excitation coils 860 and 862, and the virtual coils 868 and 870 are copper, manganese-nickel-copper alloy wires, or nickel-chromium alloy wires. By using manganese-nickel-copper alloy wire and nickel-chromium alloy wire, the resistance changes little with temperature and the temperature characteristics are good.

In this embodiment, since the excitation coils 860 and 862 are formed by winding wire rods around the outside of the magnetic core portion 61b and the outside of the peripheral wall portion 61c made of ferrite or the like, it is possible to increase the eddy flow flowing through the measurement target object. current density. In addition, since the detection coils 864 and 866 are also formed outside the magnetic core portion 61b and the peripheral wall portion 61c, the generated reverse magnetic field (linkage magnetic flux) can be effectively collected.

In order to increase the eddy current density flowing through the measurement target, in this embodiment, the excitation coil 860 and the excitation coil 862 are further connected in parallel as shown in FIG. 19 . That is, the inner coil and the outer coil are electrically connected in parallel. The reasons for parallel connection are as follows. When connected in parallel, the voltage that can be applied to the excitation coils 860 and 862 increases, thereby increasing the current flowing through the excitation coils 860 and 862 compared to the case of a series connection. Therefore, the magnetic field increases. Also, when connected in series, the inductance of the circuit increases and thus the frequency of the circuit decreases. It becomes difficult to apply the required high frequencies to the excitation coils 860, 862. Arrow 874 indicates the direction of current flowing through excitation coils 860 and 862 .

As shown in FIG. 19 , the excitation coil 860 and the excitation coil 862 are connected so that the magnetic fields of the excitation coil 860 and the excitation coil 862 have the same direction. That is, current flows in different directions in the excitation coil 860 and the excitation coil 862 . The magnetic field 876 is the magnetic field generated by the inner excitation coil 860 , and the magnetic field 878 is the magnetic field generated by the outer excitation coil 862 . As shown in FIG. 20 , the magnetic fields of the excitation coil 860 and the excitation coil 862 have the same direction. That is, the direction of the magnetic field generated by the inner coil in the magnetic core part 61b is the same as the direction of the magnetic field generated by the outer coil in the magnetic core part 61b.

Magnetic field 876 and magnetic field 878 shown in area 880 are in the same direction, so the two magnetic fields add together and become larger. Compared with the conventional case where only the magnetic field 876 generated by the exciting coil 860 exists, in this embodiment, the amount of the magnetic field 878 generated by the exciting coil 862 is increased.

Next, unlike FIG. 19 , as shown in FIG. 21 , a case will be described in which the excitation coil 860 and the excitation coil 862 are connected so that the magnetic field directions of the excitation coil 860 and the excitation coil 862 are opposite. That is, current flows in the same direction in excitation coil 860 and excitation coil 862 . The magnetic field 876 is the magnetic field generated by the inner excitation coil 860 , and the magnetic field 878 is the magnetic field generated by the outer excitation coil 862 . As shown in FIG. 22 , the magnetic fields of the excitation coil 860 and the excitation coil 862 have opposite directions. That is, the direction of the magnetic field generated by the inner coil in the magnetic core part 61b is opposite to the direction of the magnetic field generated by the outer coil in the magnetic core part 61b.

Magnetic field 876 and magnetic field 878 shown in area 880 are in opposite directions, so the two magnetic fields cancel each other and become smaller. The magnetic field 878 generated by the outer excitation coil 862 suppresses the magnetic field 876 generated by the inner excitation coil 860 and changes the flow of the magnetic lines of force in the core portion 61b. In addition, the magnetic field shown in FIG. 22 is a case where the electric current flowing in the outer excitation coil 862 is large. When the current is large, the magnetic field generated by the excitation coil 862 is stronger than the magnetic field generated by the excitation coil 860 inside the peripheral wall portion 61c, so the magnetic field 878 suppresses the magnetic field 876. As a result, a magnetic field shown in Fig. 22 is generated.

Comparing Figure 20 with Figure 22, the following is known. The eddy current density generated in the semiconductor wafer 16 by the magnetic field shown in FIG. 20 is strong in a narrow range. The eddy current density generated in the semiconductor wafer 16 by the magnetic field shown in FIG. 22 is strong in a wide range.

FIG. 23 is a schematic diagram showing a connection example of coils of the eddy current detector. As shown in FIG. 23(a) , the detection coils 864 and 866 and the virtual coils 868 and 870 are connected in anti-phase with each other. The detection coil 864 and the detection coil 866 are connected in series. Virtual coil 868 and virtual coil 870 are connected in series. In FIG. 23 , the excitation coils 860 and 862, the detection coils 864 and 866, and the virtual coils 868 and 870 are shown as one coil.

The detection coils 864 and 866 and the dummy coils 868 and 870 form an inverted series circuit as described above, and both ends thereof are connected to the resistance bridge circuit 77 including the variable resistor 76 . The excitation coils 860 and 862 are connected to the AC signal source 52 to generate alternating magnetic flux, thereby forming an eddy current in the nearby metal film (or conductive film) mf. By adjusting the resistance of the variable resistor 76, the output voltage of the series circuit composed of the detection coils 864 and 866 and the dummy coils 868 and 870 can be adjusted to zero when the metal film (or conductive film) is not present. The signals of L ₁ and L ₃ are adjusted into the same phase by using variable impedances 76 ( VR ₁ , VR ₂ ) connected in parallel to the detection coils 864 and 866 and the virtual coils 868 and 870 respectively. That is, in the equivalent circuit of Fig. 23(b), the variable impedances VR ₁ (=VR _1-1 +VR _1-2 ) and VR ₂ (=VR _2-1 +VR _2-2 ) are adjusted so that VR _1-1 × (VR _2-2 + jωL ₃ ) = VR _1-2 × (VR _2-1 + jωL ₁ ) (1). Therefore, as shown in Figure 23(c), the signals of L ₁ and L ₃ before adjustment (shown by the dotted lines in the figure) become signals with the same phase and amplitude (shown by the solid lines in the figure).

Next, when the metal film (or conductive film) exists in the vicinity of the detection coils 864 and 866, the magnetic flux generated by the eddy current formed in the metal film (or the conductive film) passes between the detection coils 864 and 866. The virtual coils 868 and 870 are interlinked. However, since the detection coils 864 and 866 are disposed closer to the metal film (or conductive film), the balance of the induced voltages generated in the detection coils 864 and 866 and the virtual coils 868 and 870 is affected. By destroying the film, the interlinkage flux formed by the eddy current of the metal film (or conductive film) can be detected. That is, by isolating the series circuit of the detection coils 864 and 866 and the virtual coils 868 and 870 from the excitation coils 860 and 862 connected to the AC signal source, and adjusting the balance with the resistor bridge circuit, the zero point can be adjusted. Therefore, since the eddy current flowing in the metal film (or conductive film) can be detected based on the zero state, the detection sensitivity of the eddy current in the metal film (or conductive film) is improved. This makes it possible to detect the magnitude of the eddy current formed in the metal film (or conductive film) in a wide dynamic range.

FIG. 24 is a block diagram showing a synchronous detection circuit of the eddy current detector. This figure shows an example of a measurement circuit in which the impedance Z on the eddy current detector 50 side is viewed from the AC signal source 52 side. The impedance Z measurement circuit shown in this figure can extract the resistance component (R), reactance component (X), amplitude output (Z), and phase output (tan ^-1 R/X) associated with changes in film thickness.

As mentioned above, the signal source 52 that supplies the AC signal is a fixed-frequency oscillator composed of a crystal oscillator, and supplies a fixed-frequency voltage of, for example, 2 MHz, 8 MHz, or 16 MHz to the metal film (or conductive film) on which the detection target is formed. The eddy current detector 50 is located near the semiconductor wafer W of the film) mf. The AC voltage formed by the signal source 52 is supplied to the eddy current detector 50 through the band-pass filter 82 . The signal detected by the terminal of the eddy current detector 50 passes through the high-frequency amplifier 83 and the phase shift circuit 84, and the cos component of the detection signal is extracted by the synchronous detection unit composed of the cos synchronous detection circuit 85 and the sin synchronous detection circuit 86. and sin components. Here, the oscillation signal formed by the signal source 52 is formed with the in-phase component (090 cos) of the signal source 52 by the phase shift circuit 84 and the sin synchronous detection circuit 85 and the sin synchronous detection circuit 86 perform the above-mentioned synchronous detection.

The synchronously detected signal uses low-pass filters 87 and 88 to remove unnecessary high-frequency components above the signal component, and the resistance component (R) output as the cos synchronous detection output and the reactance component as the sin synchronous detection output are respectively extracted. (X) output. In addition, the vector operation circuit 89 obtains the amplitude output (R ² +X ² ) ^1/2 from the resistance component (R) output and the reactance component (X) output. In addition, the vector operation circuit 90 similarly obtains the phase output (tan ^-1 R/X) from the resistance component output and the reactance component output. Here, in order to remove noise components of the detector signal, various filters are provided in the main body of the measurement device. By setting corresponding cutoff frequencies for various filters, for example, setting the cutoff frequency of a low-pass filter in the range of 0.1 to 10 Hz, the noise component of the detector signal mixed in the grinding process can be removed and the measurement can be performed with high accuracy. The target metal film (or conductive film) is measured.

Next, an example of a method of detecting the end point using the eddy current detector 50 shown in FIG. 18 will be described with reference to FIG. 25 . In FIG. 25 , the vertical axis represents the film thickness (mm) of the semiconductor wafer 16 and the horizontal axis represents the polishing time (sec) after the start of polishing. On the horizontal axis, the number of rotations when measured by the eddy current detector 50 is also represented by an integer. 1 is the first rotation, N is the Nth rotation. The end point detection unit 28 determines the polishing rate of the semiconductor wafer 16 from the detected eddy current, and creates an approximation line based on the polishing rate (initial polishing rate formula 882). The initial polishing rate formula 882 is created using the eddy current obtained while the polishing table 30A is rotating multiple times in the initial stage of polishing.

The expected polishing amount when polishing the semiconductor wafer 16 is calculated using the polishing rate according to the initial polishing rate formula 882, and the time to reach the polishing end point 884 is detected. The end point detection unit 28 detects the polishing end point 884 based on the expected polishing amount and the threshold 886 related to the film thickness corresponding to the polishing end point 884 . At this time, when the change in the output of the eddy current detector 50 is small compared to the change in the wiring height in the semiconductor wafer 16 due to polishing, it is difficult to accurately obtain the change in the output value of the eddy current detector 50 . At this time, the cancellation algorithm of the output value of the eddy current detector 50 as shown below is executed.

In the cancellation algorithm, the end point detection unit 28 compares the film thickness-related data obtained from the eddy current and the film thickness-related data predicted from the polishing rate. If the comparison result is larger than the specified value, the end point detection unit 28 does not use the film thickness-related data obtained from the eddy current. Film thickness related information. For example, the data collected for each rotation is compared with the data related to the film thickness predicted from the initial polishing rate formula 882. If the two are significantly different from the specified value, the collected data is not used. For example, when data is collected in the N+2th spin, when the difference between the data collected in the N+2nd spin and the data collected in the N+1th spin is greater (or smaller) than in the N+1th spin When the difference (specified value) between the data collected and the data collected in the Nth spin is determined, the data collected in the N+2 spin will not be used. Instead, use the value based on the initial grind rate equation 882. Whether it is not used when it is larger than the specified value or not used when it is smaller than the specified value depends on the polishing conditions such as the properties of the film.

Other situations where the collected information will not be used include the following situations. For example, when data is collected on the N+2nd spin, when the data collected on the N+2nd spin is larger than the data collected on the N+1th spin, the data collected on the N+2th spin will not be used. material. Instead, use data based on the initial grind rate Equation 882.

When the data collected at the N+2nd rotation is not used, if a value close to the approximate line is obtained after the N+3rd rotation, this data is used. As mentioned above, after the polishing is started, the initial polishing rate formula 882 is created using a number of rotations. For example, it can be re-created using the latest number of rotations every ten rotations.

Next, an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion 61 a but surrounds the wall portion of the magnetic core portion 61 b will be described with reference to FIGS. 26 to 28 . In FIGS. 26 and 27 , the bottom portion 61 a has a columnar shape, and the peripheral wall portion 61 c is the eddy current detector 50 (magnetic element) arranged at both ends of the columnar shape. Figure 26 is a top view. Fig. 27 is a cross-sectional view taken along line AA in Fig. 26. Two peripheral portion magnetic bodies 61d are provided in the peripheral portion of the bottom portion 61a. This eddy current detector 50 is an E-type magnetic element as shown in FIG. 27 . FIG. 28 is a plan view of four eddy current detectors 50 (magnetic elements) in which the peripheral magnetic body 61d is provided on the peripheral portion of the bottom surface 61a. The number of peripheral magnetic bodies 61d may be five or more.

In the case of an E-type magnetic element, the coil arrangement may be the coil arrangement shown in FIGS. 49 and 50 in addition to the arrangement shown in FIGS. 26 and 27 . Figure 49 is a top view. FIG. 50 is a cross-sectional view taken along line AA in FIG. 49 . In the embodiment shown in FIGS. 49 and 50 , detection coils 864a and 864b are further provided on the outer periphery of the portion 61e of the bottom portion 61a between the magnetic core portion 61b and the peripheral portion magnetic body 61d, and the excitation coils 860a, 860b and virtual coils 868a, 868b. At least one of the detection coils 864a and 864b, the excitation coils 860a and 860b, and the dummy coils 868a and 868b may also be provided in the portion 61e. In addition, in the embodiment shown in FIGS. 49 and 50 , only the excitation coils 860 a and 860 b and the dummy coils 868 a and 868 b may be provided as the excitation coils and the dummy coils without providing the excitation coil 860 and the dummy coil 868 .

The detection coil 864a and the detection coil 864b may be electrically connected by a wire, or may be electrically independent without being connected by a wire. The excitation coil 860a and the excitation coil 860b, and the dummy coil 868a and the dummy coil 868b may be electrically connected by wires, or may be electrically independent without being connected by wires.

Next, referring to FIG. 48 , an embodiment will be described in which the intensity of the magnetic field generated by the excitation coil 860 and/or the excitation coil 862 is changed when the conductivity of the semiconductor wafer 16 changes. Hereinafter, an embodiment in which the intensity of the magnetic field generated by the excitation coil 860 and the excitation coil 862 is changed will be described. However, only one of the excitation coil 860 and the excitation coil 862 may change the intensity of the generated magnetic field.

In FIG. 48 , an insulating layer 888 (insulating portion) is formed on the semiconductor wafer 16 , and a conductive layer 890 such as copper is formed on the insulating layer 888 . Polishing is performed from the state of FIG. 48(a) through the state of FIG. 48(b) to the state of FIG. 48(c). The conductive layer 890 is used as wiring, for example.

In the state of FIG. 48( a ), since the conductive layer 890 exists on the front surface of the semiconductor wafer 16 , the conductive layer 890 will generate a large amount of eddy current. In the state of FIG. 48( c ), since the conductive layer 890 only exists in a smaller portion of the semiconductor wafer 16 , the conductive layer 890 will generate less eddy current. From the state of Fig. 48(a) to the state of Fig. 48(b), the intensity of the magnetic field generated by the excitation coils 860 and 862 is small. When the state of FIG. 48(b) is reached, the intensity of the magnetic field generated by the excitation coils 860 and 862 increases. This is because the conductivity of the semiconductor wafer 16 changes when it reaches the state of FIG. 48( b ).

When the conductivity of the semiconductor wafer 16 changes, the time point at which the intensity of the magnetic field generated by the excitation coils 860 and 862 is changed may be when the polishing of the portion 892 of the insulating layer 888 shown in FIG. 48(a) is completed. , instead of becoming the state in Figure 48(b).

In order to increase the intensity of the magnetic field generated by the excitation coils 860 and 862, the current flowing through the excitation coils 860 and 862 is increased, or the voltage applied to the excitation coils 860 and 862 is increased. As another method of increasing the intensity of the magnetic field, a state in which only one of the excitation coil 860 and the excitation coil 862 is used may be changed to a state in which both the excitation coil 860 and the excitation coil 862 are used.

In addition, a plurality of eddy current detectors may be disposed inside the polishing table instead of changing the intensity of the magnetic field generated by the excitation coil 860 and/or the excitation coil 862 when the conductivity of the semiconductor wafer 16 changes. The plurality of eddy current detectors have different detection sensitivities. From the state of FIG. 48(a) to the state of FIG. 48(b) , the eddy current detector 50 with low detection sensitivity is used. When the state of FIG. 48(b) is reached, the eddy current detector 50 with high detection sensitivity is used.

Here, "the detection sensitivities are different from each other" means "the intensity of the generated magnetic field is different" and/or "the range of the generated magnetic field is different", etc. Cases that require a plurality of eddy current detectors with mutually different detection sensitivities include the following cases, for example. (a) When it is necessary to measure the film thickness of multiple wafers with different proportions of conductive films in one wafer, (b) When it is necessary to analyze the thickness in the height direction 896 as shown in Fig. 48(a) The case where the film thickness of a plurality of wafers with different polishing amounts needs to be measured, (c) the case where the film thickness of a plurality of wafers with different polishing amounts needs to be measured in the height direction 896 shown in Figure 48(a), etc. .

The case (c) in which it is necessary to measure the film thickness of a plurality of wafers with different polishing amounts in the height direction 896 is, for example, the following case. At the start of polishing, the conductive layer 890 (Cu wiring) has the distance LL in the height direction shown in FIG. 48(a) . At the end of polishing, the conductive layer 890 has a distance LS in the height direction 896 shown in FIG. 48(c). There are various possibilities as combinations of distance LL and distance LS. Depending on the range of distance LL, a plurality of detectors with different resolutions are sometimes required.

As a method of changing the detection sensitivity, the method of arranging a plurality of eddy current detectors inside the polishing table has been described above. However, as a method of changing the detection sensitivity, only the excitation coil 860 shown in FIG. 18 and One side of the excitation coil 862. That is, as a method of changing the detection sensitivity, the following method can be adopted, which includes: as the grinding table 30A rotates, through at least one of the first step, the second step, and the third step, the detection coil 864 and/or the detection The coil 866 detects the eddy current formed in the semiconductor wafer 16; and the step of detecting a polishing end point indicating the completion of polishing of the semiconductor wafer 16 from the detected eddy current. In the first step, the eddy current formed in the semiconductor wafer 16 by the excitation coil 860 is detected by the detection coil 864 and/or the detection coil 866 . In the second step, the eddy current formed in the semiconductor wafer 16 by the excitation coil 862 is detected by the detection coil 864 and/or the detection coil 866 . In the third step, the eddy current formed in the semiconductor wafer 16 by both the excitation coil 860 and the excitation coil 862 is detected by the detection coil 864 and/or the detection coil 866 .

The outer diameter of excitation coil 860 is smaller than the outer diameter of excitation coil 862 . Therefore, compared with the range of the magnetic field generated by the excitation coil 860 alone and the range of the magnetic field generated by the excitation coil 862 alone, the range of the magnetic field generated by the excitation coil 862 alone is larger. Therefore, the exciting coil 860 can measure the film thickness in a narrow area. The excitation coil 862 can measure the film thickness in a wide area.

When both the excitation coil 860 and the excitation coil 862 are used, the magnetic fields generated by the excitation coil 860 and the excitation coil 862 can be combined (synthesized) for control. By combined control, both the expansion area of the magnetic field and the intensity of the magnetic field can be controlled to a greater extent than when only one of the excitation coil 860 and the excitation coil 862 is used.

Which of the first step, the second step, and the third step is to be adopted may be determined by the structure of the fine circuit on the semiconductor wafer 16 or the size of the die.

In addition, the relationship between the size of the eddy current detector 50 and the wafer size of the measurement target is preferably the following relationship. For example, when the shape of the wafer is a square or a rectangle, the size of the eddy current detector 50 is preferably a circumscribed circle circumscribing the square or rectangle. The size of the eddy current detector 50 should not be too small or too large compared to the circumscribed circle. When the wafer size is extremely larger or smaller than the size of the eddy current detector 50 , the eddy current may not be detected. In this case, it may be necessary to arrange a plurality of eddy current detectors 50 with different sizes.

In addition, simply increasing the excitation coil increases the intensity of the eddy current. Therefore, when detecting the lump (film) shown in Fig. 48(a) , even simply increasing the excitation coil is effective. “Agglomerate (film)” means a conductive layer 890 that covers the entire surface of the semiconductor wafer 16 like the region 894 . In addition, "only the excitation coil is added" means that only the excitation coils 860 and 862 are provided with the outer coil, that is, the excitation coil 862, and the detection coils 864, 866, and virtual coils 868, 870 are not provided with the outer coil, that is, detection. Coil 866, virtual coil 870.

When detecting the conductive layer 890 (Cu wiring) shown in FIGS. 48(b) and 48(c) , the detection sensitivity of the eddy current detector 50 needs to be higher than that in the state of FIG. 48(a) . Therefore, In addition to the detection coils 864 and 866 and the dummy coils 868 and 870, it is sometimes preferable to provide outer coils, namely the detection coil 866 and the dummy coil 870.

Next, an example will be described in which the end point detection unit 28 detects the polishing end point indicating the end of polishing in consideration of the arm torque 26 a and the table torque detected by the arm torque detection unit 26 . In FIG. 16 , in the connection portion of the swing arm 110 connected to the swing shaft motor 14 , the arm torque detection unit 26 detects the arm torque 26 a applied to the swing arm 110 . Specifically, the arm drive unit is a swing shaft motor (rotation motor) 14 that rotates the swing arm 110 , and the arm torque detection unit 26 detects the arm torque 26 a applied to the swing arm 110 from the current value of the swing shaft motor 14 . The current value of the swing axis motor 14 is a quantity dependent on the arm torque at the connection portion of the swing arm 110 connected to the swing axis motor 14 . In the present embodiment, the current value of the swing shaft motor 14 is the current value 18b supplied from the driver 18 to the swing shaft motor 14 .

The method of detecting the arm torque 26a by the arm torque detection unit 26 will be described with reference to FIG. 29 . The driver 18 inputs a position command 65 a regarding the position of the swing arm 110 from the control unit 65 . The position command 65 a is data corresponding to the rotation angle of the swing arm 110 relative to the swing arm shaft 117 . In addition, the driver 18 inputs the rotation angle 36 a of the swing arm shaft 117 from the encoder 36 built in and attached to the swing shaft motor 14 .

The encoder 36 can detect the rotation angle 36 a of the rotation shaft of the swing shaft motor 14 , that is, the rotation angle 36 a of the swing arm shaft 117 . In this figure, the swing shaft motor 14 and the encoder 36 are shown independently. In fact, the swing shaft motor 14 and the encoder 36 are integrated. An example of such an integrated motor is a synchronous AC servo motor with a feedback encoder.

The driver 18 has a bias circuit 38 , a current generation circuit 40 , and a PWM circuit 42 . The deviation circuit 38 obtains the deviation 38a between the position command 65a and the rotation angle 36a from the position command 65a and the rotation angle 36a. The deviation 38a and the current value 18b are input to the current generating circuit 40. The current generating circuit 40 generates a current command 18a corresponding to the deviation 38a from the deviation 38a and the current current value 18b. The PWM circuit 42 receives the current command 18a and is controlled by PWM (Pulse Width Modulation) to generate the current value 18b. The current value 18 b is a three-phase (U phase, V phase, W phase) current capable of driving the swing axis motor 14 . The current value 18b is supplied to the swing shaft motor 14 .

The current command 18a is a quantity that depends on the current value of the swing axis motor 14 and depends on the arm torque. The arm torque detection unit 26 performs at least one process of AD conversion, amplification, rectification, effective value conversion, etc. on the current command 18a, and then outputs it to the end point detection unit 28 as the arm torque 26a.

The current value 18b is the current value itself of the swing shaft motor 14 and depends on the amount of arm torque. The arm torque detection unit 26 may detect the arm torque 26a applied to the swing arm 110 from the current value 18b. When the arm torque detection unit 26 detects the current value 18b, a current detector such as a Hall detector can be used.

Referring to FIG. 29 , a method of detecting the motor current by the current detection unit 810 (detection unit) will be described. The current detection unit 810 detects the motor M3 (first motor, see FIG. 2 ) for driving the polishing table to rotate, the motor M1 (the second motor, see FIG. 5 ) for driving the top ring 31A, and the motor M1 for rotating the swing arm. The current value of one of the motors in the swing motor M2 (the third motor, see Figure 5) is generated and the first output is generated. In this embodiment, the current detection unit 810 detects the current value of the motor M2 and generates the first output 810a. The current value 18b of the three phases (U phase, V phase, and W phase) is input to the current detection unit 810 .

The current detection unit 810 samples each of the U-phase, V-phase, and W-phase current values 18b, for example, every 10 msec, and obtains a 100-msec moving average for each of the sampled current values 18b. The purpose of moving average is to reduce noise. Then, full-wave rectification is performed on the U-phase, V-phase, and W-phase current values 18b, and then the effective value is obtained for each of them by effective value conversion. After calculating the effective value, the three values are added to generate the first output 810a. The current detection unit 810 outputs the generated first output 810 a to the end point detection unit 28 .

In addition, the noise reduction processing can perform various noise reduction processing, and is not limited to the above-mentioned moving average processing. In addition, the current detection unit 810 may perform processing other than effective value calculation on the current value 18b. For example, after calculating the absolute values of the current values 18b, these three values may be added together to generate the first output 810a. In addition, the current detection unit 810 may generate the sum of the squares of the absolute values of the three-phase current values of the motor as the first output. In addition, the effective value may be calculated for only one or two phases among the current values 18b of the U phase, V phase, and W phase. The first output may be any amount as long as it is an amount that can represent a change in torque. The end point detection unit 28 that detects the polishing end point indicating the end of polishing based on the first output can detect the polishing end point indicating the end of polishing from a change in the first output (friction force).

In this embodiment, the swing arm 110 which swings in the left-right direction (circumferential direction) on the plane of the polishing table 30A was demonstrated. However, this embodiment is also applicable to an arm that reciprocates in the radial direction in the linear direction between the rotation center of the polishing table 30A and the end of the polishing table 30A on the plane of the polishing table 30A.

In addition, the end point detection unit 28 can be configured as a computer including a CPU, a memory, and an input/output unit. At this time, a program functioning as the end point detection unit and the control unit for controlling polishing of the polishing device can be stored in the memory, wherein the end point detection unit can detect an indication of the semiconductor wafer 16 from the detected eddy current. The end of grinding is the grinding end point.

Next, another embodiment including an optical detector will be described with reference to FIG. 30 . In this method, the detection of the torque fluctuation of the swing axis motor 14 of the swing polishing table 30A and the detection of the reflectance of the polished surface of the semiconductor wafer 16 by an optical detector are both used. In order to detect the end point, a detector is built into the polishing table 30A. The detector is an optical detector 724. As the optical detector 724, a detector using an optical fiber or the like is used. In addition, an eddy current detector may be used instead of the optical detector 724 .

In the case of the embodiment of FIG. 30 , the following problems can be solved. When only one of the torque fluctuation detection method or the optical detection method is used for end point detection, and when polishing of the metal film and polishing of the insulating film are mixed in the polishing of the polishing target, the following problems arise. The torque fluctuation detection method is suitable for detecting the boundary between the metal film and the insulating film, and the optical detection method is suitable for detecting changes in the thickness of the film. Therefore, with only one method, when both the detection of the film boundary and the detection of the thickness of the remaining film are required, only insufficient detection accuracy can be obtained. The problem can be solved by using torque fluctuation detection and optical detection separately depending on whether it is the detection of the film boundary or the detection of the thickness of the remaining film.

In the case of an optical detector, the end point detection unit of the polishing device irradiates light to the semiconductor wafer 16 and measures the intensity of the reflected light from the semiconductor wafer 16 . The end point detection unit detects the polishing end point indicating the completion of polishing based on the arm torque detected by the arm torque detection unit and the intensity of the reflected light from the semiconductor wafer 16 measured by the optical detector 724 . The output of the optical detector 724 is sent to the control unit 65 via the wiring 726 .

In the case of an optical detector, there is an opening 720 in a part of the polishing pad 10 . The opening 720 has an observation port 722 as a viewing window. Through the observation port 722, light irradiation and reflected light detection are performed. During polishing, the observation port 722 is installed at a position in the polishing table 30A that can face the semiconductor wafer 16 . An optical detector 724 is arranged below the observation port 722 . When the optical detector 724 is an optical fiber detector, the observation port 722 may not be provided.

When there is no observation port 722, pure water may be output from the periphery of the optical fiber detector, and the slurry supplied from the nozzle 728 may be removed to detect the end point. The optical detector has a fluid supply part (not shown) that supplies pure water (or fluid such as high-purity gas or a mixture of liquid and gas) for cleaning the slurry into the opening 420 .

There may also be a plurality of detectors. For example, as shown in FIG. 30 , it is provided at the center part and the end part, and the detection signals of both the center part and the end part are monitored. FIG. 30( a ) shows the arrangement of the optical detector 724 , and FIG. 30( b ) is an enlarged view of the optical detector 724 . From these plural signals, the end point detection unit 28 selects a detection signal that is not affected by the polishing conditions (or is most suitable for the polishing conditions) in response to changes in the polishing conditions (material of the semiconductor wafer 16 , polishing time, etc.). Judge the end point and stop grinding.

This point will be explained further. The combination of the torque fluctuation detection (motor current fluctuation measurement) and optical detection performed by the swing axis motor 14 is used to detect the interlayer insulating film (ILD) and STI (Shallow Trench Isolation). It is effective when the component isolation film is formed at the polishing end point. In optical inspections such as SOPM (Spectrum Optical Endpoint Monitoring), the thickness of the remaining film is detected and endpoint detection is performed. For example, in the manufacturing process of the LSI multilayer film, it is sometimes necessary to form a residual film by polishing the metal film and polishing the insulating film. It is necessary to polish the metal film and polish the insulating film. According to the polishing of the metal film or the polishing of the insulating film, torque fluctuation detection and optical detection can be used separately.

In addition, when the film structure of the end point is a mixed state of a metal and an insulating film, it is difficult to perform accurate end point detection using only one of torque fluctuation detection and optical detection. Therefore, the film thickness is measured by torque fluctuation detection and optical detection. Based on the detection results of the two, it is determined whether the end point is reached, and polishing is completed at the most appropriate time. In a mixed state, in both torque fluctuation detection and optical detection, the measurement signal is weak, so the measurement accuracy decreases. However, by using signals obtained by two or more measurement methods, the most appropriate end position can be determined. For example, when any one of the determinations of signals obtained by two or more measurement methods results in a result that is an end point, it is determined to be an end point.

Next, another embodiment including an optical detector will be described with reference to FIG. 31 . In this method, the detection of the torque variation of the swing axis motor 14 of the swing polishing table 30A (the friction variation of the polishing table 30A), the detection of the reflectance of the polished surface of the semiconductor wafer 16 by an optical detector, are used in combination. The eddy current detector detects the eddy current in the object to be polished of the semiconductor wafer 16 . Use a combination of these three detection methods.

In the case of the embodiment of FIG. 31 , the following problems can be solved. The torque fluctuation detection method and the optical detection method of the embodiment in FIG. 30 have a problem that it is difficult to detect changes in the thickness of the metal film. The embodiment of FIG. 31 solves this problem, and the embodiment of FIG. 30 further uses detection of eddy current. Since the eddy current within the metal film is detected, it is easier to detect changes in the thickness of the metal film.

FIG. 31(a) shows the arrangement of the optical detector 724 and the eddy current detector 730. FIG. 31(b) is an enlarged view of the optical detector 724, and FIG. 31(c) is an enlarged view of the eddy current detector 730. Figure. The eddy current detector 730 is arranged in the polishing table 30A. The eddy current detector 730 generates a magnetic field in the semiconductor wafer 16 and detects the intensity of the generated magnetic field. The end point detection unit 28 detects based on the arm torque detected by the arm torque detection unit 26 , the intensity of the reflected light from the semiconductor wafer 16 measured by the optical detector 724 , and the intensity of the magnetic field measured by the eddy current detector 730 The grinding end point indicates the end of grinding.

This method is an example of combining torque fluctuation detection of the swing axis motor 14 for end point detection and detection of physical quantities of the semiconductor wafer 16 by the optical detector 724 and the eddy current detector 730 incorporated in the polishing table 30A. . The torque fluctuation detection (motor current fluctuation measurement) of the swing axis motor 14 is suitable for end point detection at a portion of the polished sample where the film quality changes. The optical method is suitable for detecting the remaining film amount of insulating films such as ILD and STI and for endpoint detection using it. The end point detection by an eddy current detector is preferably, for example, the end point detection at the point when the plated metal film is polished to the underlying insulating film as the end point.

In the manufacturing process of multi-layered semiconductors such as LSI, multiple layers made of various materials are polished. Therefore, in order to perform polishing and end-point detection of various films with high accuracy, in one embodiment, three end-point detection methods can be used. Three or more types can also be used. For example, further, torque fluctuation detection (motor current fluctuation measurement (TCM)) of the motor that rotates the polishing table 30A can be used in combination.

Using the combination of these four endpoint detections, high-function control and high-precision endpoint detection can be achieved. For example, when the top ring 31A moves (oscillates) on the polishing table 30A to perform polishing, the TCM detects the torque variation of the polishing table 30A caused by the change in the position of the top ring 31A. Thereby, by the rotation when the top ring 31A is located at the center of the grinding table 30A, when the top ring 31A moves to one end of the movable grinding table 30A, and when the top ring 31A moves to the other end of the grinding table 30A, The moment changes, and the main reason why the top ring 31A presses the sample differently can be found. When the main cause is found, feedback such as adjustment of the pressure on the surface of the top ring 31A can be performed to make the pressure on the sample uniform.

The main cause of the torque variation of the polishing table 30A caused by the change in the position of the top ring 31A is considered to be the deviation in the level of the top ring 31A and the polishing table 30A, and the levelness of the sample surface and the surface of the polishing pad 10 Due to the deviation or the difference in the degree of wear of the polishing pad 10, there will be a difference in friction between when the top ring 31A is located at the center and when the top ring 31A is located at a position deviated from the center.

In addition, when the film structure of the polishing end point of the film of the semiconductor wafer 16 is a mixed state of a metal and an insulating film, since it is difficult to perform accurate end point detection using only one detection method, the method of detecting arm torque fluctuation With the optical detection method, or the method of detecting arm torque fluctuations, the method of detecting eddy current, or all three signal detections to determine the end state, the grinding is completed at the most appropriate time. In a mixed state, the measurement signal is weak in any of the torque fluctuation detection, optical type, and eddy current detection methods, so the measurement accuracy decreases. However, by making a determination using signals obtained by three or more measurement methods, the most appropriate end position can be determined. For example, when any one of the judgments of signals obtained by three or more measurement methods is used and a result is judged to be an end point, it is judged to be an end point.

These combinations are listed below. i. Arm torque detection + table torque detection, ii. Arm torque detection + optical detection, iii. Arm torque detection + eddy current detection, iv. Arm torque detection + optical detection by microwave detector , v. Arm torque detection + optical detection + table torque detection, vi. Arm torque detection + optical detection + eddy current detection, vii. Arm torque detection + optical detection + optical detection by microwave detector Type detection, viii. Arm torque detection + eddy current detection + table torque detection, ix. Arm torque detection + eddy current detection + optical detection by microwave detector, x. Arm torque detection + table torque Detection + optical detection by microwave detector, xi. In addition, a combination of any detector combined with arm torque detection is also included.

32 , 33 , and 34 illustrate examples in which the film structure at the end portion is a mixed state of a metal and an insulating film. In the following examples, the metal is Cu, Al, W, Co and other metals, the insulating film is SiO2, SiN, glass material (SOG (Spin-on Glass), BPSG (Boron Phosphorus Silicon Glass), etc.), Lowk material, Resin materials, other insulating materials. Manufacture SiO2, SOG, BPSG, etc. by CVD or coating. Figures 32(a) and 32(b) are examples of polishing the insulating film. Figure 32(a) shows the state before polishing, and Figure 32(b) shows the state after polishing. Membrane 732 is silicon. A film 734 is formed on the film 732, and the film 734 is an insulating film such as SiO2 (thermal oxide film) or SiN. A film 736 is formed on the film 734. The film 736 is an insulating film such as an oxide film (SiO2) or a glass material (SOG, BPSG) formed by film formation. The film 736 is polished to the state shown in Fig. 32(b).

The film thickness of film 736 is measured by optical detection. The boundary 758 between film 736 and film 734, and the boundary between film 734 and film 732 are sensitive to reflection of light. Therefore, optical detection is desired. In addition, when the materials of the film 736 and the film 734 are different, the change in friction during polishing may be large. At this time, it is appropriate to use optical detection + torque detection.

Figures 33(a) and 33(b) are examples of polishing metal films. Figure 33(a) shows the state before polishing, and Figure 33(b) shows the state after polishing. The embedded part 737 is STI. A film 738 similar to the film 736 is formed on the film 734 . Gate electrode 740 is formed on film 734 . A diffusion layer 744 serving as a drain or source is formed under the film 734 . The diffusion layer 744 is connected to vertical wirings 742 such as through holes and plugs. The gate electrode 740 is connected to a vertical wiring 742 (not shown). The vertical wiring 742 penetrates the inside of the film 738 . A metal film 746 is formed on the film 738 . The vertical wiring 742 and the metal film 746 are made of the same metal. The metal film 746 is polished to the state shown in Fig. 33(b). In addition, in FIG. 33 , the gate electrode 740 and the diffusion layer 744 are formed, but other circuit components may be formed.

Since the metal film 746 is a metal film, the eddy current is detected by utilizing the fact that the waveform of the eddy current in the metal film 746 changes greatly when the metal film decreases sharply. In addition, optical detection, which utilizes a state in which the amount of reflection from the metal film is large to reduce the metal film and cause the amount of reflection to change rapidly, can be used in combination with eddy current detection. The film 738 is an insulating film, so the film thickness is measured by optical detection.

Figures 34(a) and 34(b) are examples of polishing metal films. Figure 34(a) shows the state before polishing, and Figure 34(b) shows the state after polishing. The embedded part 737 is STI. Film 738 is formed on film 734 . Gate electrode 740 is formed on film 734 . A diffusion layer 744 serving as a drain or source is formed under the film 734 . The diffusion layer 744 is connected to vertical wirings 742 such as through holes and plugs. The gate electrode 740 is connected to a vertical wiring 742 (not shown). The vertical wiring 742 penetrates the inside of the film 738 . A metal horizontal wiring 750 is formed on the through hole 742 . The metal film 748 and the horizontal wiring 750 are made of the same metal. The metal film 748 is polished to the state shown in Fig. 34(b).

Since the metal film 748 is a metal film, an eddy current detector is used to detect the eddy current. Since the insulating film 738 is an insulating film, optical detection is used to measure the film thickness. In addition, the embodiments shown below in FIG. 32 are applicable to all the embodiments in FIGS. 1 to 31 .

Next, an embodiment as a modification of FIG. 16 will be described with reference to FIG. 35 . In this embodiment, the swing arm 110 is composed of a plurality of arms. In FIG. 35 , for example, it is composed of arms 752 and arms 754 . The arm 752 is attached to the swing shaft motor 14, and the top ring 31A is attached to the arm 754. At the joint portion of the arm 752 and the arm 754, the torque variation of the swing arm is detected and the end point is detected.

In the case of the embodiment of FIG. 35 , the following problems can be solved. In the case of FIG. 16 , during end point detection, there is a problem that the accuracy of end point detection is reduced due to the influence of gap vibration etc. which will be described later. In the case of the embodiment of FIG. 35 , since the influence of gap vibration and the like can be reduced, this problem can be solved.

A torque detector that detects torque fluctuations of the swing arm is disposed at the joint portion 756 of the arm 752 and the arm 754 . The torque detector has a load cell 706 and a strain gauge. In joint 756 , arm 752 and arm 754 are secured to each other with metal piece 710 . The arm 752 is swingable by the swing shaft motor 14 . When measuring the change in torque from the change in the current of the swing motor, it is sometimes desirable to temporarily stop the swing operation to measure the change in torque. This is because noise in the motor current of the swing motor sometimes increases with the swing motion.

In the case of this mode, when the polishing torque fluctuates due to the frictional fluctuation of the portion where the film quality changes like the boundary 758 in FIG. 32( a ), the boundary 758 can be detected by the torque detector of the joint portion 756 detection. The fluctuation of the grinding torque can also be detected by the detection of the current fluctuation of the swing axis motor 14 . The torque fluctuation detection by the torque detector of the joint part 756 has the following advantages compared with the torque fluctuation detection by the current fluctuation.

Torque fluctuation detection by detecting current fluctuations may be affected by errors caused by rotational motion (oscillation) of the swing axis motor 14 , for example, clearance vibration of the swing arm 110 caused by the swing axis motor 14 . The backlash vibration refers to a vibration caused by the backlash during the rotation operation of the swing shaft motor 14 because there is some play in the mounting portion where the swing arm 110 is attached to the swing shaft motor 14 . In the torque fluctuation detection by the torque detector of the joint part 756, there is no gap vibration in the joint part 756, and the torque fluctuation corresponding to the friction change of the polishing part can be detected. Therefore, more accurate end point detection is possible. In order to reduce the gap vibration, it is sometimes necessary to stop the swing of the swing arm 110 . However, in the torque fluctuation detection using the torque detector of the joint portion 756, high-precision end point detection can be performed without stopping the swing of the swing arm 110.

This method can also be applied to the case where there are a plurality of top rings 31A or the carousel method. As LSI laminate films become thinner and functional components become miniaturized, in order to stabilize performance and maintain yield, polishing endpoints need to be performed with higher precision than ever before. This method is effective as a technology that can cope with such requirements.

Next, the control of the entire substrate processing apparatus by the control unit 65 will be described with reference to FIG. 36 . The control unit 65 that is the main controller includes a CPU, a memory, a recording medium, software recorded on the recording medium, and the like. The control unit 65 monitors and controls the entire substrate processing apparatus, and performs signal transmission and reception, information recording, and calculation for this purpose. The control unit 65 mainly transmits and receives signals with the unit controller 760 . The unit controller 760 also has a CPU, a memory, a recording medium, software recorded in the recording medium, and the like. In the case of FIG. 36 , the control unit 65 has built-in programs that function as end point detection means for detecting the polishing end point indicating the end of polishing and as control means for controlling polishing by the polishing unit. In addition, the unit controller 760 may also have part or all of the program built-in. The program can be updated. In addition, the program may not be updated.

According to the embodiment described with reference to FIGS. 36 to 38 , the following problems can be solved. There are the following points as problems of conventional control methods of typical polishing devices. Regarding endpoint detection, multiple tests are conducted before grinding the target substance. Based on the obtained data, the grinding conditions and endpoint determination conditions are obtained, and a formula as the grinding conditions is formed. Although partial signal analysis is sometimes used, a detector signal is used for semiconductor wafer structures to determine the endpoint detection process. As a result, sufficient accuracy cannot be obtained for the following requirements. In order to improve the yield of manufactured components and wafers, higher-precision endpoint detection is required during the production of components and wafers, and deviations between batches and wafers need to be suppressed to a small level. In order to achieve the above object, by using the system to perform end point detection to which the embodiments of FIG. 36 and later are applied, more accurate end point detection can be performed, the yield can be improved, and the polishing amount variation between wafers can be reduced.

In particular, it is capable of high-speed data processing, signal processing of a large number of various types of detectors, standardization of data for these signals, learning using artificial intelligence (AI) from the data, and determination for end point detection. Creation of a data set, learning by storing judgment examples from the created data set, improving the accuracy of the learning effect, updating the polishing parameters judged by the learned judgment function, and realizing high-speed reflection of the polishing parameters to the control system high-speed communication processing system, etc. These can be applied to all embodiments shown previously in Figure 35.

The unit controller 760 controls the unit 762 (one or a plurality of units) installed in the substrate processing apparatus. In this embodiment, the unit controller 760 is provided for each unit 762. As the unit 762, there is an unloading part 62, a grinding part 63, a cleaning part 64 and the like. The unit controller 760 controls the operation of the unit 762, transmits and receives signals from the monitoring detector, transmits and receives control signals, and performs high-speed signal processing. The unit controller 760 is composed of an FPGA (field-programmable gate array), an ASIC (application specific integrated circuit), and the like.

Unit 762 is operated by signals from unit controller 760 . Additionally, unit 762 receives detector signals from the detectors and sends them to unit controller 760 . The detector signal is sometimes further sent from the unit controller 760 to the control section 65 . The detector signal is processed (including arithmetic processing) by the control unit 65 or the unit controller 760, and a signal for the next action is sent from the unit controller 760. This is how unit 762 operates. For example, the unit controller 760 detects the torque variation of the swing arm 110 through the current variation of the swing shaft motor 14 . The unit controller 760 sends the detection results to the control unit 65 . The control unit 65 performs end point detection.

Examples of software include the following. The software obtains the type of polishing pad 10 and the slurry supply amount based on the data recorded in the control device (control unit 65 or unit controller 760 ). Next, the software specifies the polishing pad 10 that can be used during the maintenance period of the polishing pad 10 or until the maintenance period, calculates the slurry supply amount, and outputs it. The software may be software that can be installed in the substrate processing apparatus 764 after the substrate processing apparatus 764 is shipped.

The communication between the control part 65, the unit controller 760, and the unit 762 may be wired or wireless. Communication via the Internet or other communication means (high-speed communication via a dedicated loop) can be used with the outside of the substrate processing apparatus 764 . Regarding the communication of data, the cloud may be used through cloud collaboration, the data may be exchanged via a smartphone in a substrate processing apparatus through smartphone collaboration, or the like. Thereby, the operation status of the substrate processing apparatus and the setting information of the substrate processing can be exchanged with the outside of the substrate processing apparatus. As a communication device, a communication network can also be formed between detectors and the communication network can be utilized.

Using the above control function and communication function, the substrate processing device can be automatically operated. For automated operation, it is possible to standardize the control mode of the substrate processing apparatus and to use a threshold value for determining the polishing end point.

Enables abnormality/life prediction/judgment/display of substrate processing equipment. In addition, control for stabilizing performance can be performed.

It can automatically extract the characteristic quantities of various data and polishing data (film thickness, polishing end point) during the operation of the substrate processing device, automatically learn the operating status and polishing status, automatically standardize the control mode, and perform abnormality/life prediction/judgment. /display.

It is possible to standardize formats, etc., in communication methods, device interfaces, etc., and to use information communication between devices and devices to manage devices and devices.

Next, in the substrate processing device 764, a detector is used to obtain information from the semiconductor wafer 16, and through communication means such as the Internet, a data processing device (cloud, etc.) installed in/outside the factory where the substrate processing device is installed is ) to store data, analyze the data stored in the cloud, etc., and control the substrate processing device according to the analysis results. Fig. 37 shows the structure of this embodiment.

1. The information obtained from the semiconductor wafer 16 by the detector may be as follows. A measurement signal or measurement data related to the torque fluctuation of the swing axis motor 14, a measurement signal or measurement data of an SOPM (optical detector), a measurement signal or measurement data of an eddy current detector, or a combination of one or more of the above. Measurement signals or measurement data; 2. The function and structure of communication means such as the Internet can be as follows. The signal or data including the above-mentioned measurement signal or measurement data is transmitted to the data processing device 768 connected to the network 766 . Network 766 may be a communication means such as the Internet or high-speed communication. For example, the network 766 may be a substrate processing device, a gateway, the Internet, a cloud, the Internet, and a data processing device connected in this order. As high-speed communication, there are high-speed optical communication, high-speed wireless communication, etc. In addition, as high-speed wireless communication, Wi-Fi (registered trademark), Bluetooth (registered trademark), Wi-Max (registered trademark), 3G, LTE, etc. are considered. It is also applicable to other high-speed wireless communications. In addition, the cloud can be used as a data processing device. When the data processing device 768 is installed in a factory, it can process signals from one or more substrate processing devices in the factory. When the data processing device 768 is installed outside the factory, signals from one or more substrate processing devices in the factory can be transmitted to the outside of the factory and processed. At this time, it is possible to connect to a data processing device installed in the country or abroad. 3. The data processing device 768 analyzes the data stored in the cloud, etc., and controls the substrate processing device 764 according to the analysis results as follows. After the measurement signal or measurement data is processed, it can be transmitted to the substrate processing device 764 as a control signal or control data. The substrate processing device 764 that has received the data updates the polishing parameters related to the polishing process based on the data and performs the polishing operation. In addition, if the data from the data processing device 768 is a signal/data indicating that the end point is detected, it is determined that the end point is detected. Get to the end point and end the grind. The polishing parameters include (1) the pressing force for the four regions of the semiconductor wafer 16 , that is, the central portion, the inner middle portion, the outer middle portion, and the peripheral portion, (2) the grinding time, (3) the grinding table 30A, The rotation speed of the top ring 31A, (4) the threshold used to determine the polishing end point, etc.

Next, other embodiments will be described with reference to FIG. 38 . FIG. 38 is a diagram showing a modification of the embodiment of FIG. 37 . In this embodiment, a substrate processing device, an intermediate processing device, a network 766, and a data processing device are sequentially connected. The intermediate processing device is composed of, for example, FPGA and ASIC, and has filtering functions, computing functions, data processing functions, data composition functions, etc.

Depending on how the Internet and high-speed optical communication are used, it is divided into the following three situations: (1) The Internet is between the substrate processing device and the intermediate processing device, and the network 766 is the Internet; (2) There is high-speed optical communication between the substrate processing device and the intermediate processing device, and the network 766 is high-speed optical communication. (3) There is high-speed optical communication between the substrate processing device and the intermediate processing device, and the Internet is used from the intermediate processing device to the outside. road conditions.

(1): This is a situation where the data communication speed and data processing speed in the overall system can be the Internet communication speed. The data sampling speed is about 1~1000mS, and it can carry out data communication of multiple grinding condition parameters. In this case, the intermediate processing device 770 creates a data set to be sent to the data processing device 768 . The details of the data set are described later. The data processing device 768 that receives the data set performs data processing, for example, calculates the change value of the polishing condition parameters until the end position, creates a process plan for the polishing process, and returns it to the intermediate processing device 770 through the network 766. The intermediate processing device 770 sends the change values of the polishing condition parameters and the required control signals to the substrate processing device 764 .

In the case of (2): the communication between the substrate processing device and the intermediate processing device, the detector signal and the status management equipment between the intermediate processing device and the data processing device are high-speed communications. In high-speed communication, communication can be carried out at communication speeds of 1~1000Gbps. In high-speed communication, data, data groups, instructions, control signals, etc. can be communicated. In this case, the intermediate processing device 770 creates a data set and sends it to the data processing device 768 . The intermediate processing device 770 extracts data required for processing in the data processing device 768 and processes the data to form a data set. For example, a plurality of detector signals for end point detection are extracted and created into a data group.

The intermediate processing device 770 sends the generated data set to the data processing device 768 through high-speed communication. The data processing device 768 calculates parameter change values up to the polishing end point and creates a process plan based on the data set. The data processing device 768 receives data sets from a plurality of substrate processing devices 764 , calculates parameter update values for the next step of each device and creates a process plan, and sends the updated data sets to the intermediate processing device 770 . The intermediate processing device 770 converts the updated data set into a control signal based on the updated data set, and sends it to the control unit 65 of the substrate processing device 764 through high-speed communication. The substrate processing device 764 performs polishing in response to the updated control signal and performs end point detection with high accuracy.

Case (3): The intermediate processing device 770 receives a plurality of detector signals from the substrate processing device 764 through high-speed communication. In high-speed optical communication, it can achieve communication speeds of 1~1000Gbps. In this case, the polishing conditions can be controlled online by high-speed communication between the substrate processing device 764, the detector, the control unit 65, and the intermediate processing device 770. The data processing sequence is, for example: detector signal reception (from the substrate processing device 764 to the intermediate processing device 770), data set creation, data processing, parameter update value calculation, update parameter signal transmission, and polishing control by the control unit 65 , the updated sequence of endpoint detection.

At this time, the intermediate processing device 770 uses the intermediate processing device 770 of high-speed communication to perform high-speed end point detection control. The status signal is periodically sent from the intermediate processing device 770 to the data processing device 768, and the data processing device 768 performs monitoring and processing of the control status. The data processing device 768 receives status signals from a plurality of substrate processing devices 764 and performs planning of the next process steps for each substrate processing device 764 . The planning signal based on the planned process step is sent to each substrate processing device 764. In each substrate processing device 764, preparation for the polishing process and execution of the polishing process are performed independently of each other. In this way, the high-speed communication intermediate processing device 770 performs high-speed end point detection control, and the data processing device 768 performs status management of a plurality of substrate processing devices 764 .

Next, an example of a data group will be explained. Ability to store detector signals and required control parameters as data sets. The data set can include: the pressing of the top ring 31A to the semiconductor wafer 16, the current of the swing axis motor 14, the motor current of the polishing table 30A, the measurement signal of the optical detector, the measurement signal of the eddy current detector, and the polishing pad 10 The position of the top ring 31A above, the flow rates/types of slurry and chemical liquid, and relevant calculation data of the above data, etc.

The above types of data sets can be transmitted using a transmission system that transmits one-dimensional data in parallel or a transmission system that transmits one-dimensional data sequentially. As a data set, the one-dimensional data mentioned above can be processed into two-dimensional data and used as a data set. For example, when the X-axis is used as time and the Y-axis is used as a large number of data columns, multiple parameter data at the same time are processed into one data group. Two-dimensional data can be processed as data such as two-dimensional image data. This advantage is that for the transmission of two-dimensional data, it can be transmitted, received and processed as time-related data using fewer wirings than for the transmission of one-dimensional data. Specifically, when one-dimensional data is converted into one signal per wire as it is, a large amount of wiring is required. However, in the case of two-dimensional data transmission, multiple signals can be sent through one wire. In addition, when multiple lines are used, the interface with the data processing device 768 that receives the sent data becomes complicated, and data reorganization in the data processing device 768 becomes complicated.

In addition, when such a two-dimensional data set related to time exists, it becomes easy to compare the data set at the time of polishing under the standard polishing conditions performed in the past with the data set under the standard polishing conditions at the current point. In addition, differences between the two-dimensional data can be easily known through difference processing or the like. It also becomes easy to extract areas with differences and detect detector and parameter signals that are causing abnormalities. In addition, it becomes easy to perform abnormality detection by comparing the previous standard polishing conditions with the data set during polishing at the current point, and extracting parameter signals of locations that are different from the surroundings.

39 is a diagram illustrating another schematic configuration example of the detector (embodiment examples described in the 19th to 22nd aspects), with (a) in the same figure being a top view and (b) in the same figure being a side cross-sectional view. As shown in the figure, a liquid supply hole 1042 and a liquid discharge hole 1046 are provided (disposed in this order in the moving direction of the polishing table 30A), and the cross section of the through hole 1041 is approximately Oval shape, let the lower end surface of the through hole 1041 surround the upper end surfaces of the liquid supply hole 1042 and the liquid discharge hole 1046, so that the midpoint of the line segment connecting the center of the liquid supply hole 1042 and the center of the liquid discharge hole 1046 is aligned with the through hole 1041 The center point of is further forward in the moving direction (arrow D direction) of the polishing table 30A. Thereby, the flow of the transparent liquid Q supplied from the liquid supply hole 1042 into the through hole 1041 becomes a flow that travels perpendicularly to the polished surface 16 a of the semiconductor wafer 16 . In addition, by forming the cross section of the through hole 1041 into a substantially elliptical shape, the area of the through hole 1041 can be minimized and the influence on the polishing characteristics can be reduced.

Furthermore, the optical fiber 1043 for irradiation light and the optical fiber 1044 for reflected light are arranged in the liquid supply hole 1042 so that their center lines are parallel to the center line of the liquid supply hole 1042 . In addition, one optical fiber for irradiation and reflected light may be used instead of the optical fiber 1043 for irradiation light and the optical fiber 1044 for reflected light.

Next, embodiment examples of the twenty-third and twenty-fourth aspects will be described with reference to the drawings. FIG. 40 is a diagram showing a schematic structure of an embodiment of the present invention. In FIG. 40 , the water ejection nozzle 1005 ejects a cylindrical water stream and comes into contact with the processing surface 1002 a of the semiconductor wafer 16 on which the thin film 1002 is formed. The tip portions of the irradiation optical fiber 1007 and the light-collecting optical fiber 1008 are inserted into the water ejection nozzle 1005 .

In the above-mentioned structure, the pressurized water flow 1006 is supplied to the water ejection nozzle 1005, and the thin cylindrical water flow 1004 is brought into contact with a predetermined position on the processing surface 1002a of the semiconductor wafer 16 from the tip thereof to form the measurement point 1003. In this state, light is sent from the measurement calculation unit 1009 to the water flow 1004 through the irradiation optical fiber 1007, and the light is irradiated to the polished surface in the measurement point 1003 of the semiconductor wafer 16 through the water flow 1004. At this time, the optical axis in the water flow 1004 and the grinding surface should be approximately perpendicular to the device structure. However, depending on the situation, the optical axis in the water flow 1004 may be relatively tilted to the polished surface as long as the light collecting optical fiber 1008 can receive the light from the irradiation optical fiber and the reflected light from the polished surface is in a positional relationship.

The reflected light reflected from the treated surface (polished surface) 1002a is guided to the measurement calculation unit 1009 through the water flow 1004 and the light-collecting optical fiber 1008. In this measurement calculation unit 1009, the film thickness of the thin film 1002 is measured from reflected light. At this time, the inner surface of the water ejection nozzle 1005 is mirror-finished, and the irradiation/reflected light can be effectively guided to the irradiation optical fiber 1007 and the light collection optical fiber 1008.

In addition, it is true that water droplets may remain in the part where the film 1002 is in contact with the water flow 1004, which may confuse the measurement point 1003. Here, as shown in FIG. 41 , a drainage member 1138 spirally wound extending from the water ejection nozzle 1005 to the measurement point 1003 of the film 1002 may be provided to remove water droplets. In addition, when the water flow 1004 is tilted with respect to the semiconductor wafer, a mechanism for removing water droplets may be appropriately combined with a mechanism for supplying the water flow 1004 in the upward and downward directions. In addition, as shown in Fig. 41, as the drainage member, it is conceivable to have a structure having a spring-like shape to utilize the surface tension of water, or it may be formed of a suction nozzle (not shown) and provided to surround the water spouting member. Structure of nozzle 1005.

42 and 43 are diagrams showing a configuration example of a polishing device that polishes the polishing surface of the semiconductor wafer 16 by the relative movement of the semiconductor wafer 16 and the polishing pad 10, and detects the film thickness during polishing in real time. FIG. 42 is a partial cross-sectional side view, and FIG. 43 is a view along arrow Y-Y in FIG. 42 .

The water spray nozzle 1005 is the same as FIG. 40 and FIG. 41 . A pressurized water flow pipe 1136 is connected to the water spray nozzle 1005 . The water of the water flow 1004 sprayed from the water spray nozzle 1005 is received by the water tray 1135 and drained by the drain pipe. 1137 discharge. The upper end of the water tray 1135 opens to the upper surface of the polishing pad 10, and the water flow 1004 jetted from the water jet nozzle 1005 forms the measurement point 1003 on the polishing surface of the semiconductor wafer 16, as shown in FIGS. 40 and 41. In addition, in the figure, the water ejection nozzle 1005 is drawn relatively large in order to make it easier to understand, but in fact, in order to form tiny dots, the diameter of the water ejection nozzle 1005 is small (0.4 mm to 0.7 mm).

In the water ejection nozzle 1005, similarly to the case of FIGS. 40 and 41, the tip portions of the irradiation optical fiber 1007 and the light collection optical fiber 1008 are inserted, and are guided from the measurement calculation unit 1009 to the water ejection nozzle 1005 through the irradiation optical fiber 1007. inside, and the measurement point 1003 of the polishing surface in contact with the water jet 1004 is illuminated by the water jet 1004 jetted from the water jet nozzle 1005 . The reflected light reflected by the polished surface is guided to the measurement calculation unit 1009 via the water flow 1004 and the light-collecting optical fiber 1008 .

In a twenty-fifth aspect, the object processing apparatus is characterized in that it has a plurality of processing areas in which a plurality of processing units that have been subjected to light-shielding processing are arranged vertically and are housed inside, and a conveyor is housed inside and installed in the processing area. In the transfer area between the processing area and the transfer area, a light-shielding wall is provided between the processing area and the transfer area. The front surface of the transfer area is shielded from light by a maintenance door, and the processing units are connected to the light-shielding wall in a light-shielding state.

In this way, the processing unit is subjected to light-shielding treatment, and a light-shielding wall is provided between the processing area and the transport area in which the processing unit is arranged, and the front surface of the transport area is shielded from light by a maintenance door. Even if the maintenance door of the processing unit is opened, Even when the door is in the state, light from the outside is prevented from entering the conveyance area, and even when maintenance is performed on processing units arranged above and below, for example, the processing unit on the upper floor, the processing unit on the lower floor can be carried out in a light-shielded state. The processing of the objects to be ground. Therefore, during maintenance of a part of the processing units, the object to be polished can be processed by other processing units than the processing unit without stopping the device.

A twenty-sixth aspect is the apparatus according to the eighteenth aspect, characterized in that a workpiece insertion opening having a freely openable and closable shutter is provided, and a light-shielding film surrounding the workpiece insertion opening is provided on the light-shielding wall. An opening is provided in a region where the wall is surrounded by the light-shielding film.

Thus, with the shutter of the processing unit open, the workpiece to be polished is transferred while maintaining the light-shielded state in the processing unit and the transfer area, and by closing the shutter of the processing unit, for example, during maintenance, it is possible to prevent Light from the outside enters the conveyance area through the opening of the light-shielding wall.

A twenty-seventh aspect is the object-to-be-polished processing apparatus according to aspect 24 or 25, characterized in that the processing area is a cleaning area, and the processing of the object to be polished is cleaning of the object to be polished.

By means of the 25th to 27th methods, photocorrosion of copper wiring, etc. caused by light irradiation to the surface of the object to be polished is prevented, and during maintenance of a part of the processing unit in the device, the object to be polished Although the number of processes is temporarily reduced, it becomes possible to process the object to be polished to prevent photocorrosion of copper wiring and other components due to light irradiation.

The 25th to 27th modes may also have the following features. (1) A device that reduces electrical decomposition between metallic features in a semiconductor material including a sealing mechanism for not exposing the semiconductor material to light having energy above the energy gap energy of the semiconductor material (i.e., the substrate) middle. (2) In the device described in (1) above, the sealing mechanism is arranged around the semiconductor processing tool selected from the group consisting of a chemical mechanical polishing device and a brush cleaning device. (3) The device according to the above (2) further includes a light source capable of generating light having energy lower than the energy gap. (4) The device according to (3) above further includes a process monitoring camera capable of detecting light having energy lower than the band gap energy. (5) In the device described in (4) above, the semiconductor material is silicon-based, the sealing mechanism excludes light with a wavelength of approximately 1.1 μm or less, and the light source generates light with a wavelength exceeding approximately 1.1 μm, The camera detects it. Preferably, for example, light having a wavelength in this range, such as infrared light, may be used to detect the end point of the polishing process of the silicon-based object to be polished in the above-described polishing device. (6) In the device according to (4) above, the semiconductor material is gallium-based, the sealing mechanism excludes light having a wavelength of approximately 0.9 μm or less, and the light source generates light having a wavelength exceeding approximately 0.9 μm, The camera detects it. Preferably, for example, light having a wavelength in this range, such as infrared light, may be used to detect the end point in the polishing process of the gallium-based polished object in the polishing device described above. (7) Includes a device capable of combining at least one electrical decomposition inhibitor with a metal feature in a semiconductor material in a semiconductor processing tool to reduce electrical decomposition between metal features in the semiconductor material. (8) In the device of (7) above, the semiconductor material is silicon-based, the sealing mechanism excludes light with a wavelength of approximately 1.1 μm or less, and the light source generates light with a wavelength exceeding approximately 1.1 μm, so The camera detects it. Preferably, for example, light having a wavelength in this range, such as infrared light, may be used to detect the end point of the polishing process of the silicon-based object to be polished in the above-described polishing device.

In crystalline solids such as materials constituting integrated circuits, atomic orbitals actually combine to form "crystalline" orbitals or continuous "bands" of electron energy bands. The highest occupied band is called the valence electron band, and the lowest vacant band is called the conduction band. The energy required to excite an electron from the highest point of the valence electron band to the lowest point of the conduction band is called the energy gap energy (Eg). Silicon is Eg=1.12eV at room temperature, and gallium is Eg=1.42eV at room temperature. It is known that semiconductor materials such as silicon exhibit photoconductivity. Light irradiation gives sufficient energy to excite electrons to the conduction band, thereby increasing the conductivity of the semiconductor. Light energy is related to frequency or wavelength according to the formula E=hν or E=hc/λ. In the formula, h is Planck's constant, c is the speed of light, ν is the frequency, and λ is the wavelength. In most silicon-based semiconductors at room temperature, the light energy required to achieve photoconductivity must reach about 1.12 eV, that is, it must have a wavelength of about 1.1 μm or less. In gallium semiconductors, wavelengths of approximately 0.9 μm or less are required for photoconductivity. In other semiconductors, Eg is easily obtained from common references, and the wavelength can be calculated using the above formula. In the following description, silicon-based semiconductor elements will be focused on, but the present invention is also applicable to elements made of other semiconductor materials such as gallium, which is easily understood by those skilled in the art.

The photoconductivity described above forms the basis for the photoelectric effect in the PN junction 300 shown in FIG. 44 . The n-type semiconductor 320 is silicon doped with donor impurities such as phosphorus and arsenic that supply electrons to the silicon conduction band to generate excess negative charge carriers. Therefore, a large number of charge carriers in n-type semiconductor 320 are negatively charged particles. The p-type semiconductor 310 is silicon doped with acceptor impurities such as boron that accept electrons from the valence electron band of silicon to generate excess holes or positive charge carriers. Therefore, a large number of charge carriers in p-type semiconductor 310 are positively charged holes. When the PN junction 300 is irradiated with photons of light 350 having sufficient energy, electrons are excited from the valence electron band to the conduction band in both the p-type 310 and n-type 320 semiconductors, leaving holes. In this way, among the increased positive charge carriers generated in the n-type semiconductor 320 , a large number of charge carriers move toward the positive (hole) side, that is, the p-type 310 side of the junction 300 . In addition, among the increased negative charge carriers thus generated in the p-type semiconductor 310 , a large number of charge carriers move toward the negative (electron) side, that is, the n-type 320 side of the junction 300 . The movement of this charge carrier creates a photoelectric effect, creating a source of electrical current similar to that of a battery.

When the PN junction functioning as a current source is connected to metal conductors such as interconnects 330 and 340 exposed in the electrolyte 230, all the elements required for electrical decomposition are present, and as long as the potential is sufficient, the anode metal components will be dissolved. . The electrochemical dissolution of Figure 44 due to photovoltage is similar to the electrochemical dissolution. During the oxidation reaction at the anode 330, free cations 250 are produced that are dissolved in the electrolyte 230, and electrons flow to the current source (PN junction 300) via internal connections to the cathode 340. The most conspicuous sign of electrical decomposition caused by this oxidation reaction is the dissolution or asphalt of the anode 330, but it must also cause a reduction reaction. The reduction reaction at the cathode combines electrons with reactants 260 in electrolyte 230 to produce reduced reaction products. It should be noted that depending on which side of the p-side or n-side of the PN junction is connected, some part of the metal conductor becomes the cathode and some part becomes the anode.

In accordance with preferred embodiments of the present invention that eliminate or reduce electrochemical dissolution, methods and apparatus are provided that eliminate or reduce electrochemical dissolution of wiring, interconnects, contacts, and other metallic features throughout the entire area. This preferred embodiment reduces dissolution by not exposing the PN junction to light that can cause the photoelectric effect, or by preventing oxidation or reduction, or both, due to the photoelectric effect, or by doing both.

In addition, as a method of holding the top ring and the driving part of the top ring, in addition to the above-mentioned method of holding them at the end of the swing arm (cantilever), there are also a plurality of top rings and a plurality of driving parts of each top ring. The drive section is held in a carousel manner. Even when one embodiment of the present invention is applied to a carousel, it is possible to provide a polishing device that reduces differences in measurement results of current detectors among a plurality of polishing devices. These top rings and drive parts form a group (grinding device), and a plurality of groups can be arranged on one carousel. By applying the above-described embodiments to the current values of the motor currents of the plurality of drive units (top ring motors 114 ), it is possible to realize a polishing device in which differences in measurement results of current detectors are reduced among a plurality of sets of polishing devices.

The carousel will be described with reference to Fig. 45 . The carousel can rotate around the rotation axis 704 , and the top ring motor 114 is mounted on the carousel 702 . FIG. 45 is a schematic side view showing the relationship between the multi-head top ring 31A supported by the carousel 702 and the top ring motor 114 and the polishing table 30A. As shown in FIG. 45 , a plurality of top ring units are provided on one polishing table 30A. A top ring can also be provided on the carousel, and there can be more than one platform. It is also possible to provide a plurality of top rings on the carousel and have a plurality of stages. In this case, one top ring may be provided on one stand, or a plurality of top rings may be provided on one stand. The carousel moves such as rotating, and the top ring can also be moved to another stage and polished in the next stage.

Carousel 702 can rotate. A rotating mechanism is provided near the center of the carousel 702 . The carousel 702 is supported by pillars (not shown). The carousel 702 is supported by a rotating spindle, and the rotating spindle is attached to a motor (not shown) of the support column. Therefore, the carousel 702 can rotate around the vertical rotation axis 704 by rotating the rotation main shaft. In addition, as a method similar to the carousel method, for example, a circular guide rail may be used instead of the carousel. A plurality of drive units (top ring motors 114) are provided on the guide rail. At this time, the driving part can move on the guide rail.

Next, an embodiment in which the polishing device has a carousel that can rotate around a rotation axis and the arm drive unit is attached to the carousel will be described with reference to FIGS. 46 and 47 . FIG. 46 is a schematic side view showing the relationship between the multi-head top ring 31A and the swing arm 110 supported by the carousel 702 and the polishing table 30A, and FIG. 47 is a plan view.

According to the embodiment in which the top ring is attached to the carousel 702 shown in FIG. 46 , the following problems can be solved. When the large carousel 702 is provided with a plurality of top rings 31A, as a polishing end point detection means, different from the method based on arm torque, there is a method of monitoring the torque fluctuation of the rotation drive motor of the polishing table or the top ring rotation drive motor. Methods. In these methods, changes in the rotation resistance (friction force) of the top ring 31A are detected. However, there may be errors in the friction force detection signal due to errors caused by swings of the arm, fluctuations in the rotation of the top ring, fluctuations in the rotation of the stage, etc., and it has been difficult to achieve high-precision end point detection in the past. In addition, when a plurality of top rings are provided on a rotary table, the rotation of the table will fluctuate in a complicated manner due to the influence of the plurality of top rings 31A. Therefore, it has been difficult to obtain accurate fluctuations in the frictional force of each top ring 31A in the past.

In the polishing device of FIG. 46 , the swing arm 110 is attached to the carousel 702 , and the top ring 31A is attached to the swing arm 110 . There are cases where one unit (hereinafter referred to as “TR unit”) including one swing arm 110 and one top ring 31A is provided on the carousel 702 or a plurality of units are provided (multi-head type). FIG. 46 shows a case where a plurality of carousels 702 are provided.

In addition, in FIGS. 45 and 46 , the top ring motor 114 is disposed on the upper side of the swing arm 110 . In FIG. 46 , as shown by the dotted line, the top ring motor 114 a may be disposed on the lower side of the swing arm 110 . In addition, when one polishing table 30A shown in FIG. 45 has a plurality of top rings 31A, the swing directions or moving directions of the plurality of top rings 31A need to be moved so that the plurality of top rings 31A do not interfere with each other. For example, in the case of an arrangement where there is a possibility of interference when the plurality of top rings 31A are moved close to each other, the top rings 31A are moved so as not to be close to each other or are moved in the same direction to prevent interference.

As another embodiment, the swing arm 110 may not move on the track. For example, the polishing device includes a support frame; a rail mounted on the support frame that defines a conveyance path of the top ring motor 114; and a conveyance portion that conveys the top ring motor 114 along the path defined by the rail. Combined with the track and movable along the track.

The rails and the mechanism (transportation unit) that moves along the rails can be driven by linear motors. In addition, it can be a track mechanism using a motor and bearings. As other ways, there are ways in which the track itself can rotate. In this method, the track itself rotates so that the top ring can be moved to other stations. At this time, a small amount of movement adjustment is performed by the conveying unit.

In FIGS. 45 and 46 , a linear movement mechanism (conveyance unit) using a linear motor drive system can be used instead of the swing arm 110 . As the direction of linear movement, there is a direction of movement in one direction on the radius between the center 704 and the end of the carousel 702 . Alternatively, a mechanism that moves in the X direction, a mechanism that moves in the Y direction, and a mechanism that moves in the Z direction as shown in FIG. 47 is provided, so that movement in a combination of these movement directions can be performed. As a combination of directions, there are directions other than (X direction or Y direction) + Z direction, X direction, Y direction, etc.

In the method shown in FIGS. 45 to 47 , the arm or the conveying part swings or moves, and polishing is performed while swinging or moving. When the arm or carrying part swings or moves, the motor current signal changes even if the friction force does not change during grinding. In this case, the embodiment shown in FIG. 16 and later is effective. The embodiment shown after FIG. 16 can detect changes in frictional force caused by changes in the material of the surface of the semiconductor wafer 16 and changes in the circuit pattern as polishing proceeds. Endpoint detection is performed based on detected changes in friction.

The examples of the embodiments of the present invention have been described above. The above-described embodiments of the present invention are provided to facilitate understanding of the present invention and do not limit the present invention. Changes and improvements can be made without departing from the gist of the present invention, and the present invention naturally includes equivalents thereof. In addition, each structural element described in the scope of the claim and the specification can be arbitrarily combined or omitted as long as at least part of the above-mentioned problems can be solved or at least part of the effect can be achieved.

61a‧‧‧Bottom portion 61b‧‧‧Magnetic core portion 61c‧‧‧Peripheral wall portion 61d‧‧‧Peripheral magnetic body 860, 862‧‧‧Excitation coil 864, 866‧‧‧Detection coil 868, 870‧‧‧Virtual Coil 876, 878‧‧‧Magnetic field 882‧‧‧Initial grinding rate formula 884‧‧‧Grinding end point

FIG. 1 is a plan view showing the overall structure of a substrate processing apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing the first polishing unit. FIG. 3 is a cross-sectional view schematically showing the structure of the top ring. 4 is a cross-sectional view schematically showing another structural example of the top ring. FIG. 5 is a cross-sectional view illustrating a mechanism for rotating and swinging the top ring. FIG. 6 is a cross-sectional view schematically showing the internal structure of the polishing table. FIG. 7 is a schematic diagram showing a polishing table equipped with an optical detector. FIG. 8 is a schematic diagram showing a polishing table equipped with a microwave detector. Fig. 9 is a perspective view showing the dresser. Fig. 10(a) is a perspective view showing the sprayer, and Fig. 10(b) is a schematic diagram showing the lower part of the arm. Fig. 11(a) is a side view showing the internal structure of the atomizer, and Fig. 11(b) is a plan view showing the atomizer. Fig. 12(a) is a plan view showing the cleaning unit, and Fig. 12(b) is a side view showing the cleaning unit. FIG. 13 is a schematic diagram showing an example of a cleaning line. Fig. 14 is a longitudinal sectional view showing the upper drying module. Fig. 15 is a plan view showing the upper drying module. FIG. 16 is a schematic diagram showing the overall structure of a polishing device according to an embodiment of the present invention. FIG. 17 is a diagram showing the structure of the eddy current detector. FIG. 17(a) is a block diagram showing the structure of the eddy current detector. FIG. 17(b) is an equivalent circuit diagram of the eddy current detector. FIG. 18 is a schematic diagram showing a structural example of the eddy current detector according to this embodiment. FIG. 19 is a schematic diagram showing a connection example of the excitation coil in the eddy current detector. FIG. 20 is a diagram showing the magnetic field in the eddy current detector. FIG. 21 is a schematic diagram showing another connection example of the excitation coil in the eddy current detector. FIG. 22 is a diagram showing the magnetic field in the eddy current detector. FIG. 23 is a schematic diagram showing a connection example of coils in the eddy current detector. FIG. 24 is a block diagram showing a synchronous detection circuit of the eddy current detector. FIG. 25 shows an example of an end point detection method using an eddy current detector. FIG. 26 shows an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion but surrounds the wall portion of the core portion. FIG. 27 shows an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion but surrounds the wall portion of the core portion. FIG. 28 shows an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion but surrounds the wall portion of the core portion. FIG. 29 is a block diagram illustrating a method of detecting arm torque by the arm torque detecting unit. FIG. 30 is a diagram showing another embodiment including an optical detector. FIG. 31 is a diagram showing another embodiment including an optical detector. FIG. 32 is a diagram showing an example of a case where the film structure of the terminal portion is a mixed state of a metal and an insulating film. FIG. 33 is a diagram showing an example of a case where the film structure of the terminal portion is a mixed state of a metal and an insulating film. FIG. 34 is a diagram showing an example of a case where the film structure of the terminal portion is a mixed state of a metal and an insulating film. FIG. 35 is a diagram showing an embodiment as a modified example of FIG. 16 . FIG. 36 is a diagram showing overall control by the control unit. FIG. 37 is a diagram showing the structure of another embodiment. FIG. 38 is a diagram showing a modification of the embodiment of FIG. 37 . Fig. 39 is a diagram showing another schematic structural example of the detector of the polishing device according to the present invention. Fig. 39(a) is a top view and Fig. 39(b) is a side sectional view. FIG. 40 is a diagram showing a schematic configuration example of another embodiment. FIG. 41 is a diagram showing a schematic configuration example of another embodiment. FIG. 42 is a diagram showing a schematic configuration example of a polishing device according to another embodiment. FIG. 43 is a view along arrow Y-Y in FIG. 42 . FIG. 44 is a cross-sectional view showing an example of PN connection. FIG. 45 is a schematic side view showing the relationship between the multi-head type top ring supported by the carousel and the polishing table. 46 is a schematic side view showing the relationship between a multi-head top ring supported by a carousel having an arm drive unit and a polishing table. FIG. 47 is a top view of the embodiment shown in FIG. 46 . 48 is a diagram illustrating an embodiment of changing the intensity of the magnetic field generated by the excitation coil when the conductivity of the semiconductor wafer changes. FIG. 49 shows an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion but surrounds the wall portion of the core portion. FIG. 50 shows an example in which the peripheral magnetic body is not provided on the peripheral portion of the bottom surface portion but surrounds the wall portion of the core portion.

L1: self-induction

L2: self-induction

50: Eddy current detector

60:can core

61a: Bottom surface

61b: Magnetic core part

61c: Peripheral wall

860: coil

862:Coil

864:Coil

866:Coil

868:Coil

870:Coil

872:Central axis

Claims (18)

A magnetic element, characterized by having: a bottom magnetic body; a central magnetic body, the central magnetic body is arranged at the center of the bottom magnetic body; a peripheral magnetic body, the peripheral magnetic body is arranged at the periphery of the bottom magnetic body; an inner coil, the inner coil is arranged at the periphery of the central magnetic body and can generate a magnetic field; and an outer coil, the outer coil is arranged at the periphery of the peripheral magnetic body and can generate a magnetic field, the outer coil surrounds the inner coil, and the magnetic element has a detection coil, the detection coil is arranged at the periphery of the central magnetic body and can detect the magnetic field. The magnetic element according to claim 1, wherein the bottom magnetic body has a columnar shape, and the peripheral magnetic bodies are arranged at both ends of the columnar shape. The magnetic element as described in claim 1 is characterized in that the peripheral magnetic body is provided in plurality at the peripheral portion of the bottom magnetic body. The magnetic element according to claim 1, wherein the peripheral magnetic body is a wall provided at the peripheral part of the bottom magnetic body to surround the central magnetic body. The magnetic element according to any one of claims 1 to 4, characterized in that the inner coil and the outer coil can be connected electrically in parallel. The magnetic element according to any one of claims 1 to 4, characterized in that the direction of the magnetic field generated by the inner coil in the central magnetic body is the same as the direction of the magnetic field generated by the outer coil in the central magnetic body. Can be the same. The magnetic element according to any one of claims 1 to 4, further comprising a detection coil arranged on the outer periphery of the peripheral magnetic body and capable of detecting a magnetic field. The magnetic element according to claim 7, further comprising a dummy coil arranged on the outer periphery of the central magnetic body and/or the outer periphery of the peripheral magnetic body and capable of detecting a magnetic field. The magnetic element according to any one of claims 1 to 4, characterized by having a virtual coil arranged on the outer periphery of the central magnetic body and capable of detecting a magnetic field. An eddy current detector, characterized by having the magnetic element described in any one of claims 7 to 9. A grinding device, characterized by having: a grinding table, a grinding pad for grinding an object to be polished can be attached to the grinding table; a driving part capable of driving the grinding table to rotate; and a holding part capable of Hold the object to be polished and press it to the polishing pad; the eddy current detector according to claim 10, which is arranged inside the polishing table and can detect by the detection coil eddy currents formed on the object to be polished by the inner coil and the outer coil as the grinding table rotates; and an end point detection unit capable of detecting the eddy current from the detected eddy current. The current detection indicates the polishing end point indicating the completion of polishing of the object to be polished. The grinding device according to claim 11, wherein the end point detection unit determines the grinding rate of the object to be ground based on the detected eddy current, and calculates the grinding rate of the object to be ground at the grinding rate. The expected amount of grinding when grinding the object, so that the grinding end point can be detected. The polishing device according to claim 12, wherein the end point detection unit compares the data related to the film thickness obtained from the eddy current with the data related to the film thickness predicted from the polishing rate. If the result is larger than the specified value, the data related to the film thickness obtained from the eddy current need not be used. The polishing device according to claim 12 or 13, wherein the end point detection unit is capable of detecting the polishing end point from the expected polishing amount and a threshold value related to a film thickness corresponding to the polishing end point. A polishing method for polishing between a polishing pad and an object to be polished arranged opposite to the polishing pad, characterized in that it includes: a step of holding the polishing pad with a polishing table; and a rotational drive The steps of the polishing table; the step of rotationally driving a holding portion for holding the object to be polished and pressing it against the polishing pad; and arranging the eddy current detector according to claim 10 inside the polishing table. , using the detection coil to detect the eddy current formed in the object to be polished by the inner coil and the outer coil as the grinding table rotates; from the detected eddy current The current detection step is a step of the polishing end point indicating the completion of polishing of the object to be polished. The polishing method according to claim 15, characterized in that the intensity of the magnetic field generated by the internal coil and/or the external coil is changed when the electrical conductivity of the object to be polished changes. The grinding method according to claim 15 or 16, characterized in that a plurality of eddy current detectors according to claim 10 are arranged inside the grinding table, and the detection of the plurality of eddy current detectors The sensitivities differ from each other. A computer-readable recording medium that records a program for causing a computer to function as an end point detection unit and a control unit for controlling a grinding device that grinds an object to be ground, so The grinding device has: a grinding table, a grinding pad for grinding the object to be polished can be attached to the grinding table; a driving part capable of driving the grinding table to rotate; and a holding part capable of holding the grinding table. The object to be polished is pressed to the polishing pad; the eddy current detector according to claim 10, which is arranged inside the polishing table and can detect the accompanying detection by the detection coil. The rotation of the polishing table causes eddy currents formed on the object to be polished by the inner coil and the outer coil, and the end point detection unit can detect and indicate the said eddy current from the detected eddy currents. The control means controls the grinding by the grinding device at the grinding end point where grinding of the object to be grinded is completed.