CN105659363B - The determination of eddy current sensor gain - Google Patents
The determination of eddy current sensor gain Download PDFInfo
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- CN105659363B CN105659363B CN201480057958.2A CN201480057958A CN105659363B CN 105659363 B CN105659363 B CN 105659363B CN 201480057958 A CN201480057958 A CN 201480057958A CN 105659363 B CN105659363 B CN 105659363B
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B49/00—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
- B24B49/10—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation involving electrical means
- B24B49/105—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation involving electrical means using eddy currents
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/304—Mechanical treatment, e.g. grinding, polishing, cutting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/005—Control means for lapping machines or devices
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
- H01L21/30625—With simultaneous mechanical treatment, e.g. mechanico-chemical polishing
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/30—Structural arrangements specially adapted for testing or measuring during manufacture or treatment, or specially adapted for reliability measurements
- H01L22/34—Circuits for electrically characterising or monitoring manufacturing processes, e. g. whole test die, wafers filled with test structures, on-board-devices incorporated on each die, process control monitors or pad structures thereof, devices in scribe line
Abstract
In one aspect, the method for polishing is controlled the following steps are included: receiving the measurement of the original depth to the conductive film on first substrate from associated mode or single machine monitoring system before polishing first substrate；One or more substrates are polished in polishing system, one or more of substrates include first substrate；During polishing one or more substrate, using one or more the substrate of eddy current monitoring system monitoring to generate the first signal；The initial value of the starting of the determining polishing for first substrate, described first signal；For at least partly, determining gain based on initial value and to the measurement of original depth in the first signal for being collected into during polishing at least one substrate in one or more substrate；And second signal is calculated based on the first signal and gain.
Description
Technical field
The disclosure about chemically mechanical polishing, and more specially about during chemically mechanical polishing to the prison of conductive layer
It surveys.
Background technique
Integrated circuit is usually formed in substrate by conductive, the sequence of semiconductive or insulating layer on silicon deposition
On.Various manufacturing process need the planarization to the layer on substrate.For example, a manufacturing step is related on nonplanar surface
Upper deposit filler layer, and planarize packing layer.For certain applications, packing layer is through planarization, until exposing through pattern
Until the top surface of the layer of change.For example, metal layer can be deposited on the ditch filled in this insulating layer on patterned insulating layer
Slot and hole.After planarization, the metal in the groove and hole of patterned layer rest part formed through-hole, plug and
Line, these through-holes, plug and line provide conductive path between the thin film circuit on substrate.
Chemically-mechanicapolish polish (Chemical mechanical polishing；It CMP is) a kind of it has been accepted that planarization
Method.This flattening method usually requires to assemble substrate on carrier head.The surface that is exposed of substrate is usually placed against
Rotary polishing pad.Carrier head provides controlled load on substrate to push this substrate against polishing pad.To usually have mill
The polishing slurries of grain are supplied to the surface of polishing pad.
A problem in CMP is to judge whether polishing process is completed (i.e., if be planarized to substrate layer required
When Pingdu or thickness have removed the desired amount of material).It is opposite between paste composition, polishing pad condition, polishing pad and substrate
The variation of speed, the original depth of substrate layer and the load on substrate can lead to the variation of material removal rate.These are changed
Lead to the variation of time needed for reaching polishing end point.Therefore, determine that polishing end point will lead to chip according only to polishing time
Inhomogeneities between interior or chip and chip.
In some systems, (for example, passing through polishing pad) (in-situ) monitoring substrate in situ during polishing.It is a kind of
Monitoring technology is to induce eddy current in the conductive layer, and the change of eddy current is detected when removing conductive layer.
Summary of the invention
In one aspect, the following steps are included: before polishing first substrate, reception comes from a kind of method of control polishing
The measurement to the conductive film original depth on first substrate of associated mode or single machine monitoring system；One is polished in polishing system
Or more substrate, one or more of substrates include first substrate；During polishing one or more substrate, benefit
With one or more the substrate of eddy current monitoring system monitoring to generate the first signal；Determine the polishing for being used for first substrate
Starting, the initial value of the first signal；For in polishing one or more substrate during at least one substrate
The first signal being collected at least partly, determines gain based on initial value and to the measurement of original depth；Based on first
Signal and gain calculate second signal；And determine polishing eventually at least one substrate in the substrate based on second signal
Point or at least one of the adjustment to burnishing parameters.
Implementation may include one of following characteristics or more person.
The step of calculating second signal can comprise the following steps that multiplied by gain.
Calculating second signal can comprise the following steps that calculating V'=V*G+K, and wherein V' is second signal, and V is the first letter
Number, G is gain, and K is offset.
At least one substrate in one or more substrate can be first substrate.
At least one substrate in one or more substrate can be polished second after first substrate
Substrate.
Polishing system may include rotatable platform, and the eddy current sensor of eddy current monitoring system is supported on platform
On with inswept across one or more substrate.
The first signal can be generated from the part of signal generated when eddy current sensor is not adjacent to substrate.
Reference value can be determined from the part of signal generated when eddy current sensor is not adjacent to substrate.
It can be deviated by adjusting reference value to generate, to generate the desired value for being directed to zero thickness.
The step of determining gain, which can comprise the following steps that, to be associated with from by thickness to the calibration function of signal strength and to first
Desired value is determined in the measurement of beginning thickness.
It determines that gain can comprise the following steps that according to following equation and calculates multiplier N:
Wherein, D is desired value, and S is initial value, and K is to indicate calibration function for the constant of the value of zero thickness.
The step of determining gain, which can comprise the following steps that, makes old gain multiplied by N.
The step of determining initial value can comprise the following steps that generates measurement value sequence from the first signal；By Function Fitting
To the measurement value sequence；And initial value is calculated as the function in the value of the approximate initial time of polishing operation.
On the other hand, (computer program product is in non-transitory computer-readable medium for computer program product
Encoded with tangible form) it include instruction, described instruction is operable such that data processing equipment executes operation to execute the above method
In any method.
On the other hand, polishing system includes: rotatable platform, is used to support polishing pad；Carrier head, for holding first
Substrate is against polishing pad；Eddy current in situ monitors system, and the monitoring system includes that sensor depends on substrate to generate
Conductive layer thickness the first signal；And controller, the controller are configured to execute any side in the above method
Method.
On the other hand, a kind of method of control polishing at the first polishing station the following steps are included: polish substrate；When
During polishing substrate at first polishing station, using the first eddy current monitoring system monitoring substrate to generate the first signal；It determines and uses
In polishing of the substrate at the first polishing station end, the end value of the first signal；Determine the first temperature at the first polishing station
Degree；After polishing substrate at the first polishing station, substrate is polished at the second polishing station；When the polishing base at the second polishing station
During plate, using the second eddy current monitoring system monitoring substrate to generate second signal；It determines for substrate in the second polishing station
The starting of the polishing at place, second signal initial value；For being received during polishing at least one substrate at the second polishing station
In the second signal collected at least partly, the gain of the second polishing station is determined based on end value, initial value and the first temperature；
Third signal is calculated based on second signal and gain；And based on third signal be at least one substrate determine polishing end point or
At least one of adjustment to burnishing parameters.
Implementation may include one of following characteristics or more person.
The step of determining the gain of the second polishing station can further include steps of second at the second polishing station of measurement
Temperature.
Gain can be calculated based on the resistivity for the layer being just polished with the first and second temperature.
[1+ α (TE can be calculatedpost-TEini)], wherein TEpostIt is the first temperature at the first polishing pad, TEiniIt is the second throwing
Second temperature at light pad, and α is the resistivity factor of the material of polished layer.
It can determine the end of the polishing for substrate at the first polishing station, the first signal end value.
It determines that end value can comprise the following steps that and generates the first measurement value sequence from the first signal；First function is intended
It is bonded to the first measurement value sequence；And end value is calculated as the end of time that the function polishes at the first polishing station
The value at place.
First thickness can be determined from end value and calibration function, thickness is associated with strong to signal by the calibration function
Degree.
Adjusted thickness can be determined based on first thickness, the first temperature and second temperature.
The step of determining adjusted thickness, which can comprise the following steps that, makes first thickness multiplied by [1+ α (TEpost-TEini)],
Wherein TEpostIt is the first temperature at the first polishing pad, TEiniIt is the second temperature at the second polishing pad, and α is to be thrown
The resistivity factor of the material of the layer of light.
Desired value can be determined from adjusted value and calibration function.
It can determine the starting of the polishing for substrate at the second polishing station, the first signal initial value.
The step of determining initial value can comprise the following steps that generates the second measurement value sequence from second signal；By second
Function Fitting to it is described second measurement value sequence；And initial value is calculated as throwing of the second function at the second polishing station
The value of the approximate initial time of light.
The step of determining gain, which can comprise the following steps that, calculates multiplier N according to following equation:
Wherein, D is desired value, and S is initial value, and K is to indicate calibration function for the constant of the value of zero thickness.
First temperature can be the temperature of the first polishing pad at the first polishing station, and second temperature can be the second polishing
Stand place the second polishing pad temperature.
First temperature can be the temperature for the layer being polished at the first polishing station, and second temperature can be the second throwing
The temperature for the layer being polished at light station.
On the other hand, (computer program product is in non-transitory computer-readable medium for computer program product
Encoded with tangible form) it is operable such that data processing equipment executes operation to execute any method in the above method.
On the other hand, polishing system includes: the first polishing station, and first polishing station includes: to be used to support the first throwing
First platform of light pad；First eddy current in situ monitors system, and the described first eddy current monitoring system in situ includes first sensor
To generate the first signal of the thickness dependent on the conductive layer on substrate；And first temperature sensor；Second polishing station, institute
Stating the second polishing station includes: the second platform for being used to support the second polishing pad；And second eddy current in situ monitor system, it is described
First eddy current monitoring system in situ includes second sensor to generate the binary signal of the thickness of the conductive layer depended on substrate；
For holding the carrier head of substrate；And controller, the controller are configured to execute any method in the above method.
Implementation may include one of following advantage or more person.Monitoring system gain and offset can automatically be adjusted
To compensate the parameter that may influence eddy current signals.For example, mat thickness can be polished for environmental condition (for example, temperature) or such as
Etc the change of device parameter come adjust gain and offset.The endpoint system for detecting required polishing end point can be improved
Reliability, and the thickness offset in chip between chip can be reduced.
The details of one or more implementations is illustrated in attached drawing and following description.According to this description and attached drawing
And claims, other aspects, feature and advantage will be evident.
Detailed description of the invention
Fig. 1 illustrates the exemplary cross sectional view of polishing station, and the polishing station includes eddy current monitoring system.
The cross sectional view for the example magnetic fields that Fig. 2 diagram is generated by eddy current sensor.
Fig. 3 illustrates the top view of exemplary chemical mechanical polishing station, and the chemical mechanical polishing stations show the sensing across chip
Device scan path.
Fig. 4 illustrates the figure of the example eddy current phase signal of the function as conductive layer thickness.
The figure of example track of Fig. 5 diagram from eddy current monitoring system.
Fig. 6 is for starting in polishing station to the flow chart of the polishing operation of substrate.
Fig. 7 is the flow chart for substrate to be transferred to the second polishing station from the first polishing station.
In various figures, similar component symbol and the similar element of specified instruction.
Specific embodiment
A kind of monitoring technology for controlling polishing operation is to carry out driving signal on substrate using alternating current (AC)
Eddy current is induced in conductive layer.Induced eddy current can be measured in situ during polishing by eddy current sensor to generate
Signal.It is assumed that being subjected to conductive layer when the outermost layer of polishing, then the signal from sensor should depend on the thickness of layer.
The different aspect of the signal obtained from sensor can be used in the different implementations of eddy current monitoring system.Example
Such as, the amplitude of signal can be the function of the thickness for the conductive layer being polished.In addition, AC driving signal with come from sensor
Signal between phase difference can be the conductive layer being polished thickness function.
Due to the variation of ingredient and component, different gain and partially can be presented when measuring eddy current for eddy current sensor
It moves.Eddy current can also by environmental parameter (for example, polishing during substrate temperature) variation influenced.It is changed (such as, when operation
Pad wear) or the variation (for example, in situ in monitoring system) of pressure that is applied on polishing pad eddy current sensing can be changed
The distance between device and substrate, and also will affect measured eddy current signals.Therefore, it can be performed and system monitored to eddy current
Be calibrated to compensate these variations.
Fig. 1 illustrates the example of the polishing station 22 of chemical-mechanical polisher.Polishing station 22 includes rotatable disc-shaped platform
24, polishing pad 30 is located on the platform 24.Platform 24 can be operated to rotate around axis 25.For example, 21 pivotable drive of motor
Axis 28 carrys out rotating platform 24.Polishing pad 30 can be the two-layer polishing pad with outer layer 34 and softer back sheet 32.
Polishing station 22 may include supply port or combined type supply rinse arm 39 to apply polishing liquid 38 (such as, slurry)
It is fitted on polishing pad 30.
Carrier head 70 can be operated to hold substrate 10 against polishing pad 30.Carrier head 70 is from support construction 60 (for example, revolution
Expect frame or track) it is suspended, and carrier head rotating electric machine 76 is connected to by drive shaft 74, so that this carrier head can enclose
It is rotated around axis 71.Optionally, carrier head 70 can laterally vibrate, for example, on the sliding block on rotational material frame or track 60 laterally
Ground oscillation, or laterally vibrated by the rotational oscillation of rotational material frame itself.In operation, platform is revolved around central shaft 25
Turn, and carrier head is rotated around central shaft 71 and the top surface across polishing pad 30 laterally translates.With multiple carryings
In the case where head, each carrier head 70 can have the independent control to its burnishing parameters, for example, each carrier head can
Independently control the pressure for being applied to each corresponding substrate.
Carrier head 70 may include the fixed ring 84 for holding substrate.In some implementations, fixed ring 84 may include
The part of highly conductive, for example, load-carrying ring may include contacting the thin lower part parts of plastics 86 of polishing pad with thick upper guide
Electric part 88.In some implementations, the part of highly conductive is metal, for example, gold identical with the layer being polished
Belong to, for example, copper.
Groove 26 is formed in platform 24, and thin section 36 may be formed in the polishing pad 30 overlayed on groove 26.It is recessed
Slot 26 and thin liner section 36 can be positioned such that the translation position regardless of carrier head, and groove 26 and thin liner section 36 are all
All pass through below substrate 10 during a part of platform rotation.It is assumed that polishing pad 30 is two-layer liner, then it can be by going
Thin liner section 36 is constituted except the part of back sheet 32.
Polishing station 22 may include the condition for having the pad conditioner equipment of adjustment disk 31 to maintain polishing pad.
In some implementations, polishing station 22 includes the temperature sensor 64 for the temperature in monitoring system.Although
Temperature sensor 64 is illustrated as being located to the temperature of monitoring polishing pad 30 and/or the slurry 38 on liner 30 in Fig. 1, still
This temperature sensor 64 can be positioned on inside carrier head the temperature for measuring substrate 10.
Polishing station may include in-situ monitoring system 40.In-situ monitoring system 40 generates the thickness degree depended on substrate 10
The value sequence of time-varying.Particularly, in-situ monitoring system 40 can be eddy current monitoring system.Similar eddy current monitors system
Described in U.S. Patent No. 6,924, No. 641, the 7th, 112, No. 960 and the 7th, 016, No. 795, these United States Patent (USP)s it is complete
Whole disclosure is hereby incorporated herein by.
In some implementations, polissoir includes additional polishing station.For example, polissoir may include two or three
A polishing station.For example, polissoir may include monitoring the first polishing station of system with the first eddy current and with the second whirlpool
Second polishing station of current monitoring system.
For example, in operation, a large amount of polishings to the conductive layer on substrate can be executed in the first polishing station, and when conduction
The target thickness of layer can stop polishing when keeping on the electrically conductive.Then, substrate is transferred to the second polishing station, and can be to base
Plate is polished to underlying layer (for example, patterned dielectric layer).
The cross sectional view for the example magnetic fields 48 that Fig. 2 diagram is generated by eddy current sensor 49.Eddy current sensor 49 can
It is positioned at least partially in groove 26 (see Fig. 1).In some implementations, eddy current sensor 49 includes that there are two poles for tool
The core 42 and driving coil 44 of 42a and 42b.Magnetic core 42 can receive AC (exchange) electric current in driving coil 44, and
Magnetic field 48 can be generated between pole 42a and 42b.Magnetic field 48 generated can extend across thin liner section 36 and enter substrate 10
In.Sensing coil 46 generates the signal for depending on the eddy current being induced in the conductive layer 12 of substrate 10.
The top view of Fig. 3 diagram platform 24.When platform 24 rotates, sensor 49 is inswept below substrate 10.By pressing
Specific frequency is sampled the signal from sensor, and sensor 49 is given birth to across substrate 10, at a series of sampling regions 96
At measurement.For inswept each time, measurements of the optional or combination at one or more sampling regions 96.As a result, via
Repeatedly inswept, the measurement selected or combined provides the value sequence of time-varying.In addition, can be in 49 delocalization of sensor under substrate 10
Chip external pelivimetry is executed at the position of side.
Referring back to Fig. 1 and Fig. 2, in operation, oscillator 50 is coupled to driving coil 44, and controls driving coil 44
To generate oscillating magnetic field 48, this oscillating magnetic field 48 extends through the main body of core 42 and extends to two magnetic pole 42a of core 42
In gap between 42b.The thin liner section 36 at least partly extending through polishing pad 30 in magnetic field 48 simultaneously extends to substrate
In 10.
If conductive layer 12 (for example, metal layer) is present on substrate 10, oscillating magnetic field 48 can give birth in this conductive layer
At eddy current.Eddy current generated can be detected by sensing coil 46.
As polishing continues, material is removed from conductive layer 12, so that conductive layer 12 is thinner, thereby increases conduction
The resistance of layer 12.Therefore, the eddy current induced in layer 12 changes as polishing continues.As a result, being passed from eddy current
The signal of sensor changes as conductive layer 12 is polished.Fig. 4 shows curve graph 400, this curve graph 400 illustrates conductive layer thickness
With the relationship between the signal from eddy current monitoring system 40.
In some implementations, the vibration of the output of eddy current monitoring system 40 and the electric current of the flowing in sensing coil 46
Proportional signal.In some implementations, the electricity that eddy current monitoring system 40 is exported and flowed in driving coil 44
Flow the signal proportional to the phase difference between the electric current flowed in sensing coil 46.
Polishing station 22 may also comprise position sensor 80 (such as, optical interrupter) when to sense eddy current sensor 49
When substrate is left positioned at 10 lower section of substrate and eddy current sensor 49.For example, position sensor 80 may be mounted at and carry
At first 70 positions being relatively fixed.Flag 82 may be attached to the periphery of platform 24.The attachment point and length of flag 82 are chosen,
When core 42 is inswept below substrate 10, this 82 available signal of flag notifies position sensor 80.
Alternatively, polishing station 22 may include the encoder for determining the Angle Position of platform 24.Each time along with platform
Rotation, eddy current sensor can be inswept below substrate.
In operation, polishing station 22 determines the time when most of packing layer has been removed using monitoring system 40
And/or when underlying stop-layer has been exposed.In-situ monitoring system 40 can be used for determination and be removed from the surface of substrate
Material amount.
Referring back to Fig. 1 and Fig. 3, general programmable digital computer 90 can be connected to sensing circuit system 94, this sense
Slowdown monitoring circuit system 94 can receive eddy current signals.
Computer 90 can be programmed to: sample eddy current signals when substrate substantially overlays on eddy current sensor 49；It deposits
Store up sampled signal；And end point determination Logic application in the signal stored and is detected into polishing end point；And/or calculating pair
Burnishing parameters adjust (for example, change to the pressure applied by carrier head) to improve polishing uniformity.For detector logic
Possible endpoint criteria include region minimum value or maximum value, gradient change, amplitude or gradient threshold value or above-mentioned each
Combination.
Component in eddy current monitoring system other than coil and core is (for example, oscillator 50 and sensing circuit system
94) can be far from platform 24, and the component that can be coupled in platform by rotating electrical connector 29 or mountable in platform and lead to
Rotating electrical connector 29 is crossed to communicate with the computer 90 of platform exterior.
In addition, computer 90 can also be programmed to: coming from eddy current sensor 49 under substrate according to sampling frequency measurement
The eddy current signals inswept each time of side, to generate the measurement sequence in multiple sampling regions 96；Calculate each sampling area
The radial position in domain；Amplitude measurement result is divided into multiple radial extensions；And using from one or more radial models
The measurement result enclosed is to determine polishing end point and/or calculate the adjustment to burnishing parameters.
It is former since eddy current sensor 49 is inswept along with the rotation each time of platform and below substrate 10
Position ground and by it is continuous in real time in a manner of assemble information about conductive layer thickness.During polishing, eddy current sensor 49 is come from
Measurement can be displayed on output device 92 to permit the progress that the operator of polishing station visually monitors polishing operation.Passing through will
Measurement result is arranged in radial extension, the data of the conductive film thickness about each radial extension can be fed into control
Device (for example, computer 90) is to adjust the polish pressure distribution applied by carrier head.
In some implementations, eddy current signals can be used to trigger the change of burnishing parameters in controller.For example, control
Paste composition can be changed in device.
Fig. 5 shows the track 500 generated by eddy current monitoring system.As described previously for sensor across each of substrate
When secondary scanning, sampling signal is to generate one or more measurements 510.Pass through Multiple-Scan as a result, eddy current monitors system
Generate measurement value sequence 510.This measurement value sequence can be considered track 500.In some implementations, the measurement in scanning or
Measurement from Multiple-Scan can be averaging or be filtered (for example, can moving average calculation) to generate the measurement of track 500
510。
Measurement value sequence can be used for determining terminal or the change to burnishing parameters, such as non-homogeneous in chip to reduce
Property.For example, (measured value is about the time) function 520 can be fitted to measured value 510.Function 520 can be polynomial function, example
Such as, linear function.Calculated time when can reach target value 530 based on linear function 520 predicts terminal 540.
As noted previously, as component variations and environment or system parameter change with the time, eddy current monitors system can
It can need to calibrate.When sensor is initially mounted in chemical mechanical polishing stations 22, adjustable eddy current monitors system.Whenever adding
Carried base board is to monitor system for when polishing, can automatically calibrate eddy current, and/or eddy current monitoring can be calibrated during polishing
System.
Signal from eddy current sensor may be drifted about by environmental parameter (for example, temperature of eddy current sensor itself)
Influence.Executable drift compensation (for example, as described in United States Patent (USP) case the 7th, 016,795) is to compensate some changes.So
And this drift-compensation techniques may not be able to solve each provenance of signal change, and may be unable to satisfy increasingly strict technique
Demand.
In combination with the measurement from eddy current sensor in situ to use the substrate from in-line arrangement or single machine measuring station
Measurement, to calibrate the gain of eddy current monitoring system.For example, can based on from measuring station measurement and calibration curve come really
The fixed required initial signal from eddy current sensor in situ.It then, can be based on expected initial signal and from whirlpool in situ
The comparison of the practical initial signal of current sensor calculates the adjustment to gain.
In some implementations, equation (1) can be used to execute calibration with correcting gain.In equation (1), N is to use
In the correction factor of correcting gain.D is the required eddy current signals of the conductive layer thickness measured.S be starting measured value (that is,
The eddy current signals measured when polishing and starting), and K is the constant for indicating the desired value at chip external position.K may be set to pre-
If value.
N=(D-K)/(S-K) (1)
New gain G' can be calculated based on old gain G and correction factor, for example, G'=G*N.
In some implementations, it is used according to the calculated correction factor of value of S and D from a substrate for adjusting
In the gain of the in-situ monitoring system of that substrate.For example, calibration may be expressed as: Gn=Gn-1*Nn, wherein GnIt is for adjusting the
The gain of n substrate, Gn-1It is the gain for adjusting (n-1) a substrate, and NnIt is according to from the number from n, ground substrate
According to the calculated correction factor of value of the S and D of middle determination.
In some implementations, it is used according to the calculated correction factor of value of S and D from a substrate for adjusting
In the gain of the in-situ monitoring system of subsequent substrate.For example, calibration may be expressed as: Gn+1=Gn-1*Nn, wherein Gn+1It is to be used for
Adjust the gain of (n+1) a substrate, Gn-1It is the gain for adjusting (n-1) a substrate, and NnIt is according to from from n-th
The calculated correction factor of value of the S and D that are determined in the data of a substrate.
In some implementations, can based on by thickness be associated with to eddy current signals it is pre-established (that is, polishing substrate it
Before) calibration curve calculate required eddy current signals D.The example of Fig. 4 diagram calibration curve 410.In some implementations
In, calibration curve is based on the eddy current signals value being collected into from " gold system " polishing station.Therefore, in the ideal case, all throwings
Light station will all generate identical eddy current signals for identical conductive layer thickness.
Fig. 6 shows the technique 600 for control base board polishing (for example, chemically mechanical polishing).Measurement is selected on substrate
Region (610).This region can be the radial extension of substrate.For example, may be selected to be empirically determined based on previous measurement as tool
There is the radial extension of low axis asymmetry.For example, this region can be the radial model of both center and peripherals of discharge substrate
It encloses.For example, this region can be the radial extension of the 20mm from substrate center to 40mm.It in some implementations, can be by
User for example selects this region based on the input being input in graphic user interface.
Before polishing, the thickness (620) of outer conducting layer is measured in selected region.Outer conducting layer can be metal
Layer, such as, copper.The thickness measured is stored as to initial conductive layer thickness.This thickness measure is not executed by in-situ monitoring system.
On the contrary, this thickness measure can be by such as eddy current metering system (for example, the iMap that can be bought from company, Applied MaterialsTMDiameter
To scanning system) etc, associated mode suitable for measuring conductive layer thickness or single machine metering system execute.
Substrate is loaded into the polishing station (630) including eddy current monitoring system.Substrate is loaded into polishing station can be
Initial conductive layer thickness is measured to occur later.As an example, substrate can be loaded into the throwing with in-situ monitoring system 40
In light station 22.
Substrate is polished, and receives " original " eddy current signals (640) for coming the selected region of self-reference substrate.As showing
Example, can be received this original eddy current signals by the computer 90 of polishing station 22.As described above, computer 90 can receive entire base
The original eddy current signals of plate, and sampling received signal, it may be determined that the measurement that each is sampled is on substrate
Position, and institute's sampling and measuring can be ordered as include selected region multiple regions.As described with reference to Fig. 3, computer
90 also can receive the original eddy current signals from chip external position (for example, when eddy current sensor is not below substrate).
The received eddy current data (650) of institute are adjusted by the gain and offset that are previously calculated.For example, V' can be based on
=V*G+K calculates adjustment signal value V' from original signal value V.
In some implementations, for n-th of substrate, based on the data from first (n-1) a substrate of polishing
To calculate gain.For example,
V'n=Vn*Gn-1+ K and Gn-1=Gn-2*Nn-1
Wherein, V'nIt is the adjustment signal value of n-th of substrate, VnIt is the original signal value of n-th of substrate, Gn-1It is for adjusting
The gain of whole (n-1) a substrate, Gn-2It is the gain for adjusting (n-2) a substrate, and Nn-1It is according to from from (n-
1) the calculated correction factor of value of the S and D determined in the data of a substrate.
It is described in detail based on gain and offset by calibrating eddy current measurement sensor hereinafter with reference to step (670)
It calculates.
In some implementations, such as when polishing first substrate, this first substrate is first substrate in batch, or
The first substrate after polishing pad has been replaced, so that previous data are unreliable or unavailable, has then simply been set as gain
Preset value G0, so that V'1=V1*G0+K。
Based on the eddy current data received and the initial conductive layer THICKNESS CALCULATION new gain previously measured (or to gain
Adjustment) (660).As an example, gain calculating can be executed by the computer 90 of polishing station 22.For example, can be according to following equation
To calculate the correction factor N for gain:
N=(D-K)/(S-K).
The original depth IT of the conductive layer in selected region is measured in step 620.It can be according to calibration curve 410
(referring to fig. 4) the desired value D corresponding to original depth IT is calculated.
Starting measured value S can be determined according to eddy current data.That is, being received during the initial time period of polishing
Eddy current should correspond to original depth.For example, once having collected enough data during polishing, then function can be intended
It is bonded to adjustment value sequence.This function can be polynomial function, for example, linear function.
The S value at initial time T0 can be calculated according to institute's fitting function (referring to Fig. 5).Moment, T0 was not necessarily polishing operation
Exact initial time (for example, at the time of substrate is reduced to contact with polishing pad), but can be several seconds hereafter, example
Such as, 2 seconds or 3 seconds.In the case where not being bound by any particular theory, at the time of being reduced to contact with polishing pad using substrate
Non-natural high RST value may be provided, because polishing speed may be initially restricted, for example, due to platform is still accelerating to
The fact that the target speed of rotation.
K can be default value.K can correspond to calibration curve 410 for the value of zero layer thickness.If executing drift compensation (example
Such as, as described in United States Patent (USP) case the 7th, 016,795), then drift compensation can each time scan when automatically will be outside chip
Signal is back adjusted to K.
Then, new gain G' can be calculated as G'=G*N according to old gain G.
In some implementations, new gain is for subsequent substrate (that is, after the substrate for generating S value and D value
Substrate).In the case, G is represented by for the gain of (n+1) a substraten+1=Gn-1*Nn。
In some implementations, it after having accumulated initial value S of enough data to determine front substrate, calculates new
Gain, and calculate using new gain the net data set of front substrate.In the case, the gain for n-th of substrate can
It is expressed as Gn=Gn-1*Nn。
For example, when polishing first substrate (for example, the first substrate in batch or first after having replaced polishing pad
Substrate), this new gain can be used for current substrate.For then polished substrate, this new gain can be used for subsequent substrate.
In some implementations, gain value sequence is filtered (such as to inhibit the noise between chip and chip, so that increasing
Benefit further smoothly changes) to generate the filtered yield value for giving substrate.Then, G can be replaced in above-mentioned equation and
Use this filtered yield value.For example, gain can be subjected to recursive notch filter.
In any implementation, adjusted data are for determining polishing end point or modification burnishing parameters (670).Through adjusting
Entire data can indicate the thickness just in polished conductive layer, and can be used for triggering the change of burnishing parameters.Hereinbefore
The example of discovery polishing end point is described with reference to Fig. 5.
In some implementations, one or more measured zones, and the thickness in more than one region may be selected
It can be used for calibrating eddy current sensor.In some implementations, it executes at any in selected region to initial thickness
The measurement of degree.In some implementations, measurement is executed at two or more points in selected region, and to measuring
Data be averaging.
The resistivity of conductive layer can change with conductive layer temperature and be changed.Therefore the eddy current induced (and measures
Eddy current signals) depend on conductive layer resistivity.Polishing substrate increases substrate temperature and reduces induced eddy current
Signal.
If substrate is moved to the second polishing station in situ from the first polishing station in situ to continue to polish (two polishing stations
All monitored using eddy current), then the temperature change between the two polishing stations influences eddy current signals.Temperature-compensating can be by as follows
Mode executes:
Ppost=Pini[1+α(TEpost-TEini)] (2)
Tini=Tpost[Ppost/Pini] (3)
In above-mentioned equation (2) and (3), PpostIt is resistivity factor of the layer at the second polishing station, and PiniIt is same layer
Resistivity factor at the first polishing station.TEpostIt is the temperature at the second polishing station, and TEiniIt is the temperature at the first polishing station
Degree.Parameter alpha can calculate by rule of thumb, and α is very close zero value, for example, 0.002 to 0.005, such as 0.0032.Ginseng
Number α may depend on the ingredient just in polished layer.It in some implementations, can be by for inputting come selection parameter α, example
Such as, user can select from the menu for list composition of layer, and the ginseng for corresponding to selected composition of layer is determined from look-up table
Number α.Equation (5) can be used for the thickness correction carried out between two polishing stations with different temperature.
Technique 700 of Fig. 7 diagram for the control polishing when substrate is transferred to the second polishing station from the first polishing station.?
Measured zone (710) are selected on substrate.As described above, region can be the radial extension of substrate.For example, may be selected based on first
Measurement be confirmed as the radial extension of the axis asymmetry for having low by rule of thumb.It in some implementations, can be by being used for example
Such as based on the input being input in graphic user interface come selection region.
Substrate is polished at the first polishing station, and receives " original " eddy current original for coming the selected region of self-reference substrate
Beginning signal (720).As an example, eddy current signals can be received by the computer 90 of polishing station 22.As described above, computer 90 can
Receive the eddy current signals of entire substrate, and institute's sampling and measuring can be ordered as include selected region different areas
Domain.
The eddy current data received in the selected region of the first polishing station are adjusted by the first gain and offset
(730).As described in above in reference to step (670), reception gain and offset can be measured from first substrate, or can be according to
Gain and offset are calculated in the eddy current data for the front substrate being polished.First function can be fitted in the first polishing station
The eddy current data that place is collected into.First function can be the first polynomial function, for example, the first linear function.In some realities
In existing mode, in the short time interval (for example, 10 seconds) after starting for polishing, eddy current data may be unreliable, and can quilt
It abandons.
Determine the first temperature (740) of the polishing process at the first polishing station.In some implementations, this first temperature
It is the temperature of polishing pad.With substitution or in combination, the substrate temperature being polished can measure.Touch sensor
And/or noncontacting proximity sensor (for example, infrared sensor) can be used for measuring temperature.Can periodically measure temperature and/or
It can be centered around at the first polishing station at the time of stopping polishing and measure temperature.
Substrate is transferred to the second polishing station, and measures the second temperature (750) of technique at the second polishing station.It is general and
Speech can measure the temperature of element identical with the first polishing station.For example, if the first temperature is the polishing pad at the first polishing station
Temperature, then second temperature is the temperature of the polishing pad at the second polishing station.Similarly, if the first temperature is the first polishing station
The temperature of the substrate at place, then second temperature is the temperature of the substrate at the second polishing station.Temperature can periodically be measured and/or can
It is centered around to polish at the second polishing station and measures temperature at the time of beginning.
Alternatively, system can simply assume that substrate is in default temperature (example when polishing starts at the second polishing station
Such as, room temperature, for example, 21 DEG C), without measuring the second temperature at the second polishing station.
Substrate is polished at the second polishing station, and receives the original eddy current signals for coming the selected region of self-reference substrate
(760).As an example, eddy current signals can be received by the computer 90 of polishing station 22.As described above, computer 90 can receive it is whole
The eddy current initial data of a substrate, and institute's sampling and measuring can be ordered as include selected region different regions.It can
Second function is fitted to the eddy current data being collected at the second polishing station.Second function can be the second multinomial letter
Number, for example, the second linear function.
The received eddy current data (770) of the second polishing station are adjusted by the second gain and offset.As above joined
According to described in step (670), reception gain and offset can be measured from first substrate, or can be from the chip being currently polished
Gain and offset are calculated in eddy current data.In some implementations, as described in equation (2) and (3), gain adjustable
To include the difference between the first temperature and second temperature.
For example, when substrate is switched to the second polishing station from the first polishing station gain can be calculated according to following equation
Correction factor N:
N=(D'-K)/(S'-K)
It can be from the eddy current data being collected at the second polishing station come determining measuring at the second polishing station herein
Initial value S'.For example, being once collected into enough data during the polishing at the second polishing station, second function is (for example, second
Linear function) just it is fitted to adjustment value sequence.The initial time T0 from the second polishing station can be calculated from the second fitting function
The S value at place.Moment T0 is not necessarily the exact initial time of the polishing operation at the second polishing station (for example, substrate is reduced to
At the time of contact with polishing pad), but can be several seconds hereafter, for example, 2 seconds or 3 seconds.
It can determine the final thickness T of the conductive layer in the selected region at the first polishing stationpost.In some realizations
In mode, first function calculates end value DF for moment TF for calculating, and TF, actually stops at the first polishing at this moment
It stands the polishing at place.In some implementations, end value DF is simply target value 530.Can based on calibration curve 410 (referring to
Fig. 4) calculate the final thickness T corresponding to end value DFpost。
In order to execute temperature-compensating, it is based on final thickness TpostAnd the temperature at two polishing stations calculates the second polishing
The adjusted original depth T to standini.For example, can be according to Tini=Tpost(Ppost/Pini) calculate adjusted original depth.
Then, it can be calculated according to calibration curve 410 (referring to fig. 4) corresponding to adjusted original depth TiniDesired value D's.With
Afterwards, the calculating of gain can continue as discussed above.
Above-mentioned polissoir and method can be applied to various polishing systems.Polishing pad or carrier head or both it is all removable with
Relative motion is provided between polished surface and substrate.For example, platform can revolve along track, rather than rotation.Polishing pad can be
It is fixed to the liner of the circle (or some other shapes) of platform.The some aspects of end-point detecting system are applicable to linear planarization
System, for example, in the case where polishing pad is linearly moving continuous or Reel-to-reel type (reel-to-reel) band.Polishing layer
It can be standard de (for example, polyurethanes with or without filler) polishing material, flexible material, or fixed mill
Material.Use the term of relative positioning；It should be appreciated that polished surface and substrate can be retained on and be vertically oriented or some other orientation
On.
Embodiment can be realized as one or more computer program products (that is, being embodied in tangible form non-transient
One or more computer programs in machine readable storage medium), these computer program products are used for by data processing
Equipment executes or the operation for controlling data processing equipment, and the data processing equipment is for example, programmable processor, calculating
Machine or multiprocessor or computer.A large amount of embodiments of the invention have been described.It will be appreciated, however, that can carry out various modifications and
Without departing substantially from the spirit and scope of the present invention.For example, more or fewer calibration parameters can be used.In addition, can change calibration and/or
Drift compensation method.Other embodiments are in the orientation of the appended claims as a result,.
Claims (29)
1. a kind of method of control polishing, the method comprise the steps of:
Before polishing first substrate, receive from associated mode or single machine monitoring system to the first of the conductive film on the first substrate
The measurement of beginning thickness；
One or more substrates are polished in polishing system, one or more substrate includes the first substrate；
During polishing one or more substrate, system is monitored using eddy current to monitor one or more base
Plate is to generate the first signal；
The initial value of the starting of the determining polishing for the first substrate, described first signal；
Gain is determined based on the initial value and to the measurement of the original depth；
For first signal that is collected into during polishing at least one substrate in one or more substrate
At least partly, second signal is calculated based on first signal and the gain；And
Polishing end point is determined or to burnishing parameters based on the second signal at least one substrate described in the substrate
At least one of adjustment.
2. the method as described in claim 1, wherein the step of determining the gain comprise the steps of: from by thickness be associated with to
The calibration function of signal strength and in the measurement of the original depth determine desired value.
3. method according to claim 2, wherein the step of determining the gain comprise the steps of: according to following equation come
Calculate multiplier N:
Wherein, D is the desired value, and S is the initial value, and K is constant, and the constant indicates that the calibration function is directed to
The value of zero thickness, and the step of determining the gain comprises the steps of: and makes old gain multiplied by N.
4. a kind of computer-readable medium, is stored thereon with instruction, described instruction makes described when being executed by data processing equipment
Data processing equipment executes operation, and the operation includes:
Before polishing first substrate, receive from associated mode or single machine monitoring system to the first of the conductive film on the first substrate
The measurement of beginning thickness；
Polishing station is set to execute the polishing to one or more substrates in polishing system, one or more substrate includes
The first substrate；
During polishing one or more substrate, system is monitored using eddy current to monitor one or more base
Plate is to generate the first signal；
The initial value of the starting of the determining polishing for the first substrate, described first signal；
Gain is determined based on the initial value and to the measurement of the original depth；
For first signal that is collected into during polishing at least one substrate in one or more substrate
At least partly, second signal is calculated based on first signal and the gain；And
Polishing end point is determined or to burnishing parameters based on the second signal at least one substrate described in the substrate
At least one of adjustment.
5. computer-readable medium as claimed in claim 4, wherein the step of determining the gain comprises the steps of: from general
Thickness is associated with to the calibration function of signal strength and to desired value determining in the measurement of the original depth.
6. computer-readable medium as claimed in claim 5, wherein the step of determining the gain comprises the steps of: basis
Following equation calculates multiplier N:
Wherein, D is the desired value, and S is the initial value, and K is constant, and the constant indicates that the calibration function is directed to zero
The value of thickness, and the step of determining the gain comprises the steps of: and makes old gain multiplied by N.
7. a kind of polishing system for one or more substrates, the system includes:
Rotatable platform, the rotatable platform are used to support polishing pad；
Carrier head, the carrier head is for holding first substrate against the polishing pad；
Eddy current in situ monitors system, and the original position eddy current monitoring system includes that sensor to generate depends on described first
First signal of the thickness of the conductive layer on substrate；And
Controller, the controller are configured to execute operation, and the operation includes:
Receive first signal from the sensor；
The initial value of the starting of the determining polishing for the first substrate, described first signal；
Gain is determined based on the initial value and to the measurement of the original depth of the conductive layer；
Extremely for the signal that is collected into during polishing at least one substrate in the first substrate or subsequent substrate
Small part calculates second signal based on the signal and the gain；And
It is determined based on the second signal at least one substrate described in the first substrate or the subsequent substrate
Polishing end point or at least one of adjustment to burnishing parameters.
8. system as claimed in claim 7, wherein the controller is configured to be associated with from by thickness to the school of signal strength
Quasi-function and in the measurement of the original depth determine desired value.
9. system as claimed in claim 8, wherein the controller is configured to pass following operation to determine the gain:
Multiplier N is calculated according to following equation:
Wherein, D is the desired value, and S is the initial value, and K is constant, and the constant indicates that told calibration function is directed to zero
The value of thickness.
10. system as claimed in claim 9, wherein determining that the gain includes: making old gain multiplied by N.
11. system as claimed in claim 7, wherein calculating the second signal and including: multiplied by the gain.
12. system as claimed in claim 11, wherein calculating the second signal and including: calculating V'=V*G+K, wherein V' is
The second signal, V are first signals, and G is the gain, and K is offset.
13. system as claimed in claim 7, wherein at least one described substrate is the first substrate.
14. system as claimed in claim 7, wherein at least one described substrate is the subsequent substrate.
15. system as claimed in claim 7, wherein the polishing system includes rotatable platform, and the eddy current is supervised
The eddy current sensor of examining system is supported on the platform with inswept and described across one or more substrate
Controller is controlled to execute operation, and the operation includes: from the life when the eddy current sensor is not adjacent to the substrate
At signal part in generate first signal.
16. a kind of method of control polishing, the method comprise the steps of:
Substrate is polished at the first polishing station；
During polishing the substrate at first polishing station, system is monitored using the first eddy current to monitor the substrate
To generate the first signal；
Determine the end value of first signal that be used for the end of polishing of the substrate at first polishing station, described；
Determine the first temperature at first polishing station；
After polishing the substrate at first polishing station, the substrate is polished at the second polishing station；
During polishing the substrate at second polishing station, using substrate described in the second eddy current monitoring system monitoring with
Generate second signal；
Determine the initial value of second signal that be used for the starting of polishing of the substrate at second polishing station, described；
The gain of second polishing station is determined based on the end value, the initial value and first temperature；
At least portion for the second signal being collected into during polishing at least one substrate at second polishing station
Point, third signal is calculated based on the second signal and the gain；And
Based on the third signal come at least one described substrate determine polishing end point or in the adjustment of burnishing parameters extremely
Few one.
17. the method described in claim 16, wherein the step of determining the gain of second polishing station further include with
Lower step: the second temperature at measurement second polishing station.
18. method as claimed in claim 17, wherein the resistance based on the layer being polished with the first and second temperature
Rate calculates the gain.
19. a kind of computer-readable medium, is stored thereon with instruction, described instruction makes described when being executed by data processing equipment
Data processing equipment executes operation, and the operation includes:
The first polishing station is set to polish substrate；
During polishing the substrate at first polishing station, the first letter from the first eddy current monitoring system is received
Number；
Determine the end value of first signal that be used for the end of polishing of the substrate at first polishing station, described；
Determine the first temperature at first polishing station；
After polishing the substrate at first polishing station, the second polishing station is made to polish the substrate；
During polishing the substrate at second polishing station, the second letter from the second eddy current monitoring system is received
Number；
Determine the initial value of second signal that be used for the starting of polishing of the substrate at second polishing station, described；
The gain of second polishing station is determined based on the end value, the initial value and first temperature；
At least portion for the second signal being collected into during polishing at least one substrate at second polishing station
Point, third signal is calculated based on the second signal and the gain；And
Based on the third signal come at least one described substrate determine polishing end point or in the adjustment of burnishing parameters extremely
Few one.
20. computer-readable medium as claimed in claim 19, wherein the step of determining the gain of second polishing station into
One step is the following steps are included: measure the second temperature at second polishing station.
21. computer-readable medium as claimed in claim 20, wherein based on first temperature and the second temperature
The resistivity for the layer being polished calculates the gain.
22. a kind of polishing system, the polishing system includes:
First polishing station, first polishing station include: the first platform for being used to support the first polishing pad；First eddy current in situ
Monitoring system, the first eddy current monitoring system in situ include first sensor to generate the conductive layer depended on substrate
Thickness the first signal；And first temperature sensor；
Second polishing station, second polishing station include: the second platform for being used to support the second polishing pad；And second whirlpool in situ
Current monitoring system, the described second eddy current monitoring system in situ includes that second sensor depends on the substrate to generate
The conductive layer the thickness second signal；
Carrier head, the carrier head is for holding the substrate；And
Controller, the controller are configured to execute operation, and the operation includes:
Determine the end value of first signal that be used for the end of polishing of the substrate at first polishing station, described；
During polishing the substrate at second polishing station, the second letter from the second eddy current monitoring system is received
Number；
Determine the initial value of second signal that be used for the starting of polishing of the substrate at second polishing station, described；
It is determined based on the end value, the initial value and by the first temperature that first temperature sensor measures described
The gain of second polishing station；
For at least portion for the second signal that polishing is collected into during at least one substrate at second polishing station
Point, third signal is calculated based on the second signal and the gain；And
Based on the third signal come at least one described substrate determine polishing end point or in the adjustment of burnishing parameters extremely
Few one.
23. the system as claimed in claim 22, wherein second polishing station includes second temperature sensor, and wherein institute
Controller is stated to be configured to determine the gain based on the second temperature measured by the second temperature sensor.
24. system as claimed in claim 23, wherein the controller is configured to based on first temperature and described
The resistivity for the layer that second temperature is being polished calculates the gain.
25. the system as claimed in claim 22, wherein the controller is configured to pass following operation to determine the knot
Beam value: the first measurement value sequence is generated from first signal；First function is fitted to the first measurement value sequence；With
And the end value is calculated as to the value at the end of time of polishing of the function at first polishing station.
26. system as claimed in claim 23, wherein the controller is configured to close from the end value and by thickness
It is coupled in the calibration function of signal strength and determines first thickness.
27. system as claimed in claim 26, the controller is configured to based on the first thickness, first temperature
Adjusted thickness is determined with the second temperature.
28. system as claimed in claim 23, wherein first temperature is the first polishing pad at first polishing station
Temperature, and the second temperature is the temperature of second polishing pad at the second polishing station.
29. system as claimed in claim 23, wherein first temperature is being polished at first polishing station
Layer temperature, and the second temperature is the temperature for the layer being polished at second polishing station.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14/066,509 | 2013-10-29 | ||
| US14/066,571 | 2013-10-29 | ||
| US14/066,571 US9281253B2 (en) | 2013-10-29 | 2013-10-29 | Determination of gain for eddy current sensor |
| US14/066,509 US9275917B2 (en) | 2013-10-29 | 2013-10-29 | Determination of gain for eddy current sensor |
| PCT/US2014/062699 WO2015066058A1 (en) | 2013-10-29 | 2014-10-28 | Determination of gain for eddy current sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105659363A CN105659363A (en) | 2016-06-08 |
| CN105659363B true CN105659363B (en) | 2019-05-03 |
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| US11079459B2 (en) * | 2017-01-13 | 2021-08-03 | Applied Materials, Inc. | Resistivity-based calibration of in-situ electromagnetic inductive monitoring |
| TWI816620B (en) * | 2017-04-21 | 2023-09-21 | 美商應用材料股份有限公司 | Polishing apparatus using neural network for monitoring |
| JP7019305B2 (en) * | 2017-04-26 | 2022-02-15 | 株式会社荏原製作所 | How to calibrate the eddy current sensor |
| US11701749B2 (en) | 2018-03-13 | 2023-07-18 | Applied Materials, Inc. | Monitoring of vibrations during chemical mechanical polishing |
| US11577362B2 (en) | 2018-03-14 | 2023-02-14 | Applied Materials, Inc. | Pad conditioner cut rate monitoring |
| TWI825075B (en) * | 2018-04-03 | 2023-12-11 | 美商應用材料股份有限公司 | Polishing apparatus, polishing system, method, and computer storage medium using machine learning and compensation for pad thickness |
| TWI820308B (en) * | 2019-03-21 | 2023-11-01 | 美商應用材料股份有限公司 | Monitoring of polishing pad texture in chemical mechanical polishing |
| TWI754915B (en) * | 2019-04-18 | 2022-02-11 | 美商應用材料股份有限公司 | Chemical mechanical polishing temperature scanning apparatus for temperature control |
| CN111604653B (en) * | 2020-05-19 | 2021-10-01 | 安庆帝伯格茨活塞环有限公司 | Piston ring integrated forming process |
| CN115038549B (en) | 2020-06-24 | 2024-03-12 | 应用材料公司 | Substrate layer thickness determination using polishing pad wear compensation |
| CN117681117A (en) * | 2024-01-31 | 2024-03-12 | 华海清科(北京)科技有限公司 | Method and device for measuring thickness of metal film for wafer, polishing equipment and medium |
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| US7008296B2 (en) * | 2003-06-18 | 2006-03-07 | Applied Materials, Inc. | Data processing for monitoring chemical mechanical polishing |
| JP4451111B2 (en) | 2003-10-20 | 2010-04-14 | 株式会社荏原製作所 | Eddy current sensor |
| US7494929B2 (en) | 2006-04-27 | 2009-02-24 | Applied Materials, Inc. | Automatic gain control |
| JP5080933B2 (en) * | 2007-10-18 | 2012-11-21 | 株式会社荏原製作所 | Polishing monitoring method and polishing apparatus |
| JP5513795B2 (en) * | 2009-07-16 | 2014-06-04 | 株式会社荏原製作所 | Polishing method and apparatus |
| KR101482064B1 (en) * | 2008-10-16 | 2015-01-13 | 어플라이드 머티어리얼스, 인코포레이티드 | Eddy current gain compensation |
| TW201201957A (en) * | 2010-01-29 | 2012-01-16 | Applied Materials Inc | High sensitivity real time profile control eddy current monitoring system |
| US8930013B2 (en) * | 2010-06-28 | 2015-01-06 | Applied Materials, Inc. | Adaptively tracking spectrum features for endpoint detection |
| US20130065493A1 (en) * | 2011-08-09 | 2013-03-14 | Taro Takahashi | Polishing monitoring method, polishing end point detection method, and polishing apparatus |
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| TW201535491A (en) | 2015-09-16 |
| TWI641034B (en) | 2018-11-11 |
| WO2015066058A1 (en) | 2015-05-07 |
| KR102255963B1 (en) | 2021-05-24 |
| KR20160078473A (en) | 2016-07-04 |
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