Patent application number | Description | Published |
20080206993 | Using Spectra to Determine Polishing Endpoints - Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. | 08-28-2008 |
20080239308 | HIGH THROUGHPUT MEASUREMENT SYSTEM - A substrate processing system includes a processing module to process a substrate, a factory interface module configured to accommodate at least one cassette for holding the substrate, a spectrographic monitoring system positioned in or adjoining the factory interface module, and a substrate handler to transfer the substrate between the at least one cassette, the spectrographic monitoring system and the processing module. | 10-02-2008 |
20080243433 | METHODS AND APPARATUS FOR GENERATING A LIBRARY OF SPECTRA - A method of generating a library from a reference substrate for use in processing product wafers is described. The method includes measuring substrate characteristics at a plurality of well-defined points of a reference substrate, measuring spectra at plurality of measurement points of the reference substrate, there being more measurement points than well-defined points, and associating measured spectra with measured substrate characteristics. | 10-02-2008 |
20090033942 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 02-05-2009 |
20090036026 | SUBSTRATE THICKNESS MEASURING DURING POLISHING - A computer program product that determines a polishing endpoint includes obtaining spectra from different zones on a substrate during different times in a polishing sequence, matches the spectra with indexes in a library and uses the indexes to determining a polishing rate for each of the different zones from the indexes. An adjusted polishing rate can be determined for one of the zones, which causes the substrate to have a desired profile when the polishing end time is reached. | 02-05-2009 |
20090275265 | ENDPOINT DETECTION IN CHEMICAL MECHANICAL POLISHING USING MULTIPLE SPECTRA - A computer implemented method includes obtaining at least one current spectrum with an in-situ optical monitoring system, comparing the current spectrum to a plurality of different reference spectra, and determining based on the comparing whether a polishing endpoint has been achieved for the substrate having the outermost layer undergoing polishing. The current spectrum is a spectrum of light reflected from a substrate having an outermost layer undergoing polishing and at least one underlying layer. The plurality of reference spectra represent spectra of light reflected from substrates with outermost layers having the same thickness and underlying layers having different thicknesses. | 11-05-2009 |
20100035526 | CHEMICAL MECHANICAL POLISHING SYSTEM HAVING MULTIPLE POLISHING STATIONS AND PROVIDING RELATIVE LINEAR POLISHING MOTION - A chemical-mechanical polishing apparatus including a table top, a transfer station mounted on the table top, a plurality of polishing stations mounted on the table top, a plurality of washing stations, and a plurality of carrier heads supported by a support member rotatable about an axis. Each washing station is located between a first polishing station and either a second polishing station or the transfer station, and the transfer station and the plurality of polishing stations are arranged at approximately equal angular intervals about the axis. | 02-11-2010 |
20100056023 | Adjusting Polishing Rates by Using Spectrographic Monitoring of a Substrate During Processing - A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit. | 03-04-2010 |
20100103422 | GOODNESS OF FIT IN SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING - A sequence of current spectra is obtained with an in-situ optical monitoring system, and each current spectrum is compared to a plurality of reference spectra from a plurality of reference spectra libraries. The library that provides a best fit to the sequence of current spectra is determined, and a polishing endpoint is determined based on the sequence of current spectra and the library that provides a best fit to the sequence of current spectra. | 04-29-2010 |
20100105288 | MULTIPLE LIBRARIES FOR SPECTROGRAPHIC MONITORING OF ZONES OF A SUBSTRATE DURING PROCESSING - Methods, systems, and apparatus, including computer program products, for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes receiving a first sequence of current spectra of reflected light from a first zone of a substrate. A second sequence of current spectra of reflected light from a second zone of the substrate is received. Each current spectrum from the first sequence of current spectra is compared to a plurality of reference spectra from a first reference spectra library to generate a first sequence of best-match reference spectra. Each current spectrum from the second sequence of current spectra is compared to a plurality of reference spectra from a second reference spectra library to generate a second sequence of best-match reference spectra. The second reference spectra library is distinct from the first reference spectra library. | 04-29-2010 |
20100114532 | WEIGHTED SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING - A substrate having an outermost layer undergoing polishing and at least one underlying layer is irradiated with light. A sequence of current spectra is obtained with an in-situ optical monitoring system, a current spectrum from the sequence of current spectra being a spectrum of the light reflected from the substrate, wherein the current spectrum includes a range of wavelengths and, for all wavelengths in the range of wavelengths, a value corresponding to a wavelength. Further, a value of the current spectrum corresponding to a wavelength is modified with at least one value in a gain factor spectrum, wherein the gain factor spectrum includes a first range of wavelengths and, for all wavelengths in the first range of wavelengths, a value corresponding to a wavelength. The polishing of the outermost layer of the substrate is then changed based upon the modified value of the current spectrum. | 05-06-2010 |
20100124870 | Semi-Quantitative Thickness Determination - While a substrate is polished, it is also irradiated with light from a light source. A current spectrum of the light reflected from the surface of the substrate is measured. A selected peak, having a first parameter value, is identified in the current spectrum. A value of a second parameter associated with the first parameter is determined from a lookup table using a processor. Depending on the value of the second parameter, the polishing of the substrate is changed. An initial spectrum of light reflected from the substrate before the polishing of the substrate can be measured and a wavelength corresponding to a selected peak of the initial spectrum can be determined. | 05-20-2010 |
20100129939 | USING OPTICAL METROLOGY FOR WITHIN WAFER FEED FORWARD PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of a second set of parameters based on the difference, and polishing the substrate on a second platen using the adjusted parameter. | 05-27-2010 |
20100130100 | USING OPTICAL METROLOGY FOR WAFER TO WAFER FEED BACK PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of the first set of parameters based on the difference, and polishing the second substrate on the first platen using the adjusted parameter. | 05-27-2010 |
20100217430 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 08-26-2010 |
20100261413 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 10-14-2010 |
20100297916 | METHODS OF USING OPTICAL METROLOGY FOR FEED BACK AND FEED FORWARD PROCESS CONTROL - A method includes polishing a substrate on a first platen using a first set of parameters, obtaining a plurality of measured spectra from at least two zones, comparing the plurality of measured spectra with a reference spectrum to evaluate the thickness of each of the at least two zones of the substrate, comparing a thickness of a first zone with a thickness of a second zone, determining whether the thickness of the first zone falls within a predetermined range of the thickness of the second zone, and if the thickness does not fall within the predetermined range, at least one of a) adjusting at least one parameter of the first set and polishing a second substrate on the first platen using the adjusted parameters, or b) adjusting at least one parameter of a second set and polishing the substrate on a second platen using the adjusted parameters. | 11-25-2010 |
20110046918 | METHODS AND APPARATUS FOR GENERATING A LIBRARY OF SPECTRA - A method of generating a library from a reference substrate for use in processing product wafers is described. The method includes measuring substrate characteristics at a plurality of well-defined points of a reference substrate, measuring spectra at plurality of measurement points of the reference substrate, there being more measurement points than well-defined points, and associating measured spectra with measured substrate characteristics. | 02-24-2011 |
20110104987 | ENDPOINT METHOD USING PEAK LOCATION OF SPECTRA CONTOUR PLOTS VERSUS TIME - In one aspect, a method of polishing includes polishing a substrate, and receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing. The method includes measuring a sequence of spectra of light reflected from the substrate while the substrate is being polished, where at least some of the spectra of the sequence differ due to material being removed during the polishing. The method of polishing includes determining a value of a characteristic of the selected spectral feature for each of the spectra in the sequence of spectra to generate a sequence of values for the characteristic, fitting a function to the sequence of values, and determining either a polishing endpoint or an adjustment for a polishing rate based on the function. | 05-05-2011 |
20110256805 | Adaptively Tracking Spectrum Features For Endpoint Detection - A method of controlling polishing includes polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting a non-linear function to the sequence of values, determining a projected time at which the non-linear function reaches a target value; and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time. | 10-20-2011 |
20110269377 | Automatic Generation of Reference Spectra for Optical Monitoring of Substrates - A computer-implemented method of generating reference spectra includes polishing a first substrate in a polishing apparatus having a rotatable platen, measuring a sequence of spectra from the substrate during polishing with an in-situ monitoring system, associating each spectrum in the sequence of spectra with a index value equal to a number of platen rotations at which the each spectrum was measured, and storing the sequence of spectra as reference spectra. | 11-03-2011 |
20110275167 | Endpoint Method Using Peak Location Of Modified Spectra - A method of optically monitoring a substrate during polishing includes receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing, measuring a first spectrum from the substrate during polishing, the first spectrum measured within an initial time following initiation of polishing, measuring a sequence of second spectra from the substrate during polishing, the sequence of second spectra measured after the initial time, for each second spectrum in the sequence of second spectra, removing the first spectrum from the second spectrum to generate a sequence of modified third spectra, determining a value of a characteristic of the selected spectral feature for each third spectrum in the sequence of third spectra to generate a sequence of values for the characteristic, and determining a polishing endpoint or an adjustment for a polishing rate based on the sequence of values. | 11-10-2011 |
20110275281 | Dynamically Tracking Spectrum Features For Endpoint Detection - A method of controlling polishing includes polishing a substrate and receiving an identification of a selected spectral feature, a wavelength range having a width, and a characteristic of the selected spectral feature to monitor during polishing. A sequence of spectra of light from the substrate is measured while the substrate is being polished. A sequence of values of the characteristic of the selected spectral feature is generated from the sequence of spectra. For at least some spectra from the sequence of spectra, a modified wavelength range is generated based on a position of the spectral feature within a previous wavelength range used for a previous spectrum in the sequence of spectra, the modified wavelength range is searched for the selected spectral feature, and a value of a characteristic of the selected spectral feature is determined. | 11-10-2011 |
20110281501 | FEEDBACK FOR POLISHING RATE CORRECTION IN CHEMICAL MECHANICAL POLISHING - A substrate having a plurality of zones is polished and spectra are measured. For each zone, a first linear function fits a sequence of index values associated with reference spectra that best match the measured spectra. A projected time at which a reference zone will reach the target index value is determined based on the first linear function, and for at least one adjustable zone, a polishing parameter adjustment is calculated such that the adjustable zone has closer to the target index at the projected time than without such adjustment. The adjustment is calculated based on a feedback error calculated for a previous substrate. The feedback error for a subsequent substrate is calculated based on a second linear function that fits a sequence of index values associated with reference spectra that best match spectra measured after the polishing parameter is adjusted. | 11-17-2011 |
20110282477 | ENDPOINT CONTROL OF MULTIPLE SUBSTRATES WITH MULTIPLE ZONES ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING - A plurality of substrates are polished simultaneously on the same polishing pad. A sequence of spectra is measured from each zone of each substrate, and for each measured spectrum in the sequence of spectra for each zone of each substrate, a best matching reference spectrum is determined from a library of reference spectra. For each zone of each substrate, a linear function is fit to a sequence of index values associated with the best matching reference spectra. For at least one zone, a projected time at which the zone will reach a target index value is determined based on the linear function, and the polishing parameter for at least one zone on at least one substrate is adjusted such that the at least one zone of the at least one substrate has closer to the target index at the projected time than without such adjustment. | 11-17-2011 |
20110294400 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 12-01-2011 |
20110301847 | Automatic Initiation Of Reference Spectra Library Generation For Optical Monitoring - A method of generating reference spectra includes polishing a first substrate in a polishing apparatus, measuring a sequence of spectra from the first substrate during polishing with an in-situ optical monitoring system, for each spectrum in the sequence of spectra, determining a best matching reference spectrum from a first plurality of first reference spectra to generate a sequence of reference spectra, calculating a value of a metric of fit of the sequence of spectra to the sequence of reference spectra, comparing the value of the metric of fit to a threshold value and determining whether to generate a second library based on the comparison, and if the second library is determined to be generated, storing the sequence of spectra as a second plurality of reference spectra. | 12-08-2011 |
20110318992 | Adaptively Tracking Spectrum Features For Endpoint Detection - A method of controlling polishing includes polishing a substrate having a second layer overlying a first layer, detecting exposure of the first layer with an in-situ monitoring system, receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing, measuring a sequence of spectra of light from the substrate while the substrate is being polished, determining a first value for the characteristic of the feature at the time that the first in-situ monitoring technique detects exposure of the first layer, adding an offset to the first value to generate a second value, and monitoring the characteristic of the feature and halting polishing when the characteristic of the feature is determined to reach the second value. | 12-29-2011 |
20120021672 | Tracking Spectrum Features In Two Dimensions For Endpoint Detection - A method of polishing includes polishing a substrate, receiving an identification of a selected spectral feature to monitor during polishing, measuring a sequence of spectra of light reflected from the substrate while the substrate is being polished, determining a location value and an associated intensity value of the selected spectral feature for each of the spectra in the sequence of spectra to generate a sequence of coordinates, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of coordinates. At least some of the spectra of the sequence differ due to material being removed during the polishing, and the coordinates are pairs of location values and associated intensity values. | 01-26-2012 |
20120026492 | DETECTION OF LAYER CLEARING USING SPECTRAL MONITORING - A method of polishing includes polishing a substrate having a second layer overlying a first layer, measuring a sequence of groups of spectra of light from the substrate while the substrate is being polished, each group of the groups of spectra including spectra from different locations on the substrate, for each group, calculating a value for a dispersion parameter of the spectra in the group to generate a sequence of dispersion values, and detecting exposure of the first layer based on the sequence of dispersion values. | 02-02-2012 |
20120028377 | USING OPTICAL METROLOGY FOR WITHIN WAFER FEED FORWARD PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of a second set of parameters based on the difference, and polishing the substrate on a second platen using the adjusted parameter. | 02-02-2012 |
20120028813 | Selecting Reference Libraries For Monitoring Of Multiple Zones On A Substrate - A method of configuring a polishing monitoring system includes receiving user input selecting a plurality of libraries, each library of the plurality of libraries comprising a plurality of reference spectra for use in matching to measured spectra during polishing, each reference spectrum of the plurality of reference spectra having an associated index value, for a first zone of a substrate, receiving user input selecting a first subset of the plurality of libraries, and for a second zone of the substrate, receiving user input selecting a second subset of the plurality of libraries. | 02-02-2012 |
20120034844 | SPECTROGRAPHIC MONITORING USING INDEX TRACKING AFTER DETECTION OF LAYER CLEARING - A method of controlling polishing includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, polishing a substrate having a second layer overlying a first layer, measuring a sequence of spectra of light from the substrate during polishing, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, detecting exposure of the first layer, fitting a function to a portion of the sequence of index values corresponding to spectra measured after detection of exposure of the first layer, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the function. | 02-09-2012 |
20120034845 | TECHNIQUES FOR MATCHING MEASURED SPECTRA TO REFERENCE SPECTRA FOR IN-SITU OPTICAL MONITORING - A method of controlling polishing includes storing a library having a plurality of reference spectra, polishing a substrate, measuring a sequence of spectra of light from the substrate during polishing, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum using a matching technique other than sum of squared differences to generate a sequence of best matching reference spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of best matching reference spectra. Finding a best matching reference spectrum may include performing a cross-correlation of the measured spectrum with each of two or more of the plurality of reference spectra from the library and selecting a reference spectrum with the greatest correlation to the measured spectrum as a best matching reference spectrum. | 02-09-2012 |
20120100781 | MULTIPLE MATCHING REFERENCE SPECTRA FOR IN-SITU OPTICAL MONITORING - A method of controlling polishing includes storing a plurality libraries, each library including a plurality of reference spectra, polishing a substrate, measuring a sequence of spectra of light from the substrate during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching first reference spectrum from a first library from the plurality of libraries and finding a best matching second reference spectrum from a different second library from the plurality of libraries, determining a first value associated with the best matching first reference spectrum and determining a second value from the best matching second reference spectrum, and calculating a third value from the first value and the second value to generate a sequence of calculated third values. At least one of a polishing endpoint or an adjustment for a polishing rate can be determined based on the sequence of calculated third values. | 04-26-2012 |
20120231701 | FEEDBACK FOR POLISHING RATE CORRECTION IN CHEMICAL MECHANICAL POLISHING - A substrate having a plurality of zones is polished and spectra are measured. For each zone, a first linear function fits a sequence of index values associated with reference spectra that best match the measured spectra. A projected time at which a reference zone will reach the target index value is determined based on the first linear function, and for at least one adjustable zone, a polishing parameter adjustment is calculated such that the adjustable zone has closer to the target index at the projected time than without such adjustment. The adjustment is calculated based on a feedback error calculated for a previous substrate. The feedback error for a subsequent substrate is calculated based on a second linear function that fits a sequence of index values associated with reference spectra that best match spectra measured after the polishing parameter is adjusted. | 09-13-2012 |
20120276814 | AUTOMATIC SELECTION OF REFERENCE SPECTRA LIBRARY - A computer-implemented method of generating reference spectra includes polishing a plurality of set-up substrates, the plurality of set-up substrates comprising at least three set-up substrates, measuring a sequence of spectra from each of the plurality of set-up substrates during polishing with an in-situ optical monitoring system to provide a plurality of sequences of spectra, generating a plurality of sequences of potential reference spectra from the plurality of sequences of spectra, determining which sequence of potential reference spectra of the plurality of sequences provides a best match to remaining sequences of the plurality of sequences, and storing the sequence of potential reference spectra determined to provide the best match as reference spectra, and selecting and storing the sequence of potential reference spectra. | 11-01-2012 |
20120323355 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 12-20-2012 |
20130059499 | Semi-Quantitative Thickness Determination - While a substrate is polished, it is also irradiated with light from a light source. A current spectrum of the light reflected from the surface of the substrate is measured. A selected peak, having a first parameter value, is identified in the current spectrum. A value of a second parameter associated with the first parameter is determined from a lookup table using a processor. Depending on the value of the second parameter, the polishing of the substrate is changed. An initial spectrum of light reflected from the substrate before the polishing of the substrate can be measured and a wavelength corresponding to a selected peak of the initial spectrum can be determined. | 03-07-2013 |
20130204424 | Adjusting Polishing Rates by Using Spectrographic Monitoring of a Substrate During Processing - A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit. | 08-08-2013 |
20130273812 | FEEDBACK FOR POLISHING RATE CORRECTION IN CHEMICAL MECHANICAL POLISHING - A substrate having a plurality of zones is polished and spectra are measured. For each zone, a first linear function fits a sequence of index values associated with reference spectra that best match the measured spectra. A projected time at which a reference zone will reach the target index value is determined based on the first linear function, and for at least one adjustable zone, a polishing parameter adjustment is calculated such that the adjustable zone has closer to the target index at the projected time than without such adjustment. The adjustment is calculated based on a feedback error calculated for a previous substrate. The feedback error for a subsequent substrate is calculated based on a second linear function that fits a sequence of index values associated with reference spectra that best match spectra measured after the polishing parameter is adjusted. | 10-17-2013 |
20130280989 | USER-INPUT FUNCTIONS FOR DATA SEQUENCES IN POLISHING ENDPOINT DETECTION - A method of controlling polishing includes receiving user input through a graphical user interface selecting a function, the function including at least one parameter that can be varied, polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting the function to the sequence of values, the fitting including determining a value of the at least one parameter that provides a best fit of the function to the sequence of values, determining a projected time at which the function equals a target value, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time. | 10-24-2013 |
20130288571 | FEED FORWARD AND FEED-BACK TECHNIQUES FOR IN-SITU PROCESS CONTROL - During polishing of a substrate at a first platen and prior to a first time, a first sequence of values is obtained for a first zone of the first substrate and a second sequence of values is obtained for a different second zone of the substrate with an in-situ monitoring system. A first function is fit to a portion of the first sequence of values obtained prior to the first time, and a second function is fit to a portion of the second sequence of values obtained prior to the second time. At least one polishing parameter is adjusted based on the first fitted function and the second fitted function so as to reduce an expected difference between the zones. A second substrate is polished on the first platen using an adjusted polishing parameter calculated based on the first fitted function and the second fitted function. | 10-31-2013 |
20140024291 | Endpoint Detection During Polishing Using Integrated Differential Intensity - A method of controlling a polishing operation includes polishing a substrate, during polishing obtaining a sequence over time of measured spectra from the substrate with an in-situ optical monitoring system, for each measured spectrum from the sequence of measured spectra determining a difference between the measured spectrum and an immediate previous spectrum from the sequence, accumulating the difference for each measured spectrum to generate a total difference, comparing the total difference to a threshold, and detecting a polishing endpoint based on the comparison of the total difference to the threshold. | 01-23-2014 |
20140024292 | Polishing Control Using Weighting With Default Sequence - A method of controlling polishing includes storing a sequence of default values, polishing a substrate, monitoring the substrate during polishing with an in-situ monitoring system, generating a sequence of measured values from measurements from the in-situ monitoring system, combining the sequence of measured values with the sequence of default values to generate a sequence of modified values, fitting a function to the sequence of modified values, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the function. | 01-23-2014 |
20140039660 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 02-06-2014 |
20140045282 | Using Spectra to Determine Polishing Endpoints - Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. | 02-13-2014 |
20140134758 | TECHNIQUES FOR MATCHING SPECTRA - A method of controlling processing of a substrate includes measuring a spectrum reflected from the substrate, for each partition of a plurality of partitions of the measured spectrum, computing a partition value based on the measured spectrum within the partition to generate a plurality of partition values, for each reference spectrum signature of a plurality of reference spectrum signatures, determining a membership function for each partition, for each partition, computing a membership value based on the membership function for the partition and the partition value for the partition to generate a plurality of groups of membership values with each group of the plurality of groups associated with a reference spectrum signature, selecting a best matching reference spectrum signature from the plurality of reference spectra signatures based on the plurality of groups of membership values, and determining a characterizing value associated with the best matching reference spectrum signature. | 05-15-2014 |
20140141695 | Multi-Platen Multi-Head Polishing Architecture - A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. | 05-22-2014 |
20140141696 | Polishing System with In-Sequence Sensor - A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. | 05-22-2014 |
20140176949 | Automatic Initiation Of Reference Spectra Library Generation For Optical Monitoring - A method of generating reference spectra includes polishing a first substrate in a polishing apparatus, measuring a sequence of spectra from the first substrate during polishing with an in-situ optical monitoring system, for each spectrum in the sequence of spectra, determining a best matching reference spectrum from a first plurality of first reference spectra to generate a sequence of reference spectra, calculating a value of a metric of fit of the sequence of spectra to the sequence of reference spectra, comparing the value of the metric of fit to a threshold value and determining whether to generate a second library based on the comparison, and if the second library is determined to be generated, storing the sequence of spectra as a second plurality of reference spectra. | 06-26-2014 |
20140329440 | Dynamically Tracking Spectrum Features For Endpoint Detection - A method of controlling polishing includes polishing a substrate and receiving an identification of a selected spectral feature, a wavelength range having a width, and a characteristic of the selected spectral feature to monitor during polishing. A sequence of spectra of light from the substrate is measured while the substrate is being polished. A sequence of values of the characteristic of the selected spectral feature is generated from the sequence of spectra. For at least some spectra from the sequence of spectra, a modified wavelength range is generated based on a position of the spectral feature within a previous wavelength range used for a previous spectrum in the sequence of spectra, the modified wavelength range is searched for the selected spectral feature, and a value of a characteristic of the selected spectral feature is determined. | 11-06-2014 |