Upload
techdude
View
1.055
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Citation preview
TEA Systems ProductsTEA Systems Products
Critical Feature and Process Critical Feature and Process Tuning SoftwareTuning Software
Critical Feature and Process Critical Feature and Process Tuning SoftwareTuning Software
Weir PW
Weir PSFM Calibration
Weir PSFM Fixed-Focus65 Schlossburg St.Alburtis, PA 18011(+1) 610 682 4146
[email protected]://www.TEAsystems.com
Weir TR
Vector Raptor
Weir DMA
Ver: 1-June-2007
2007 TEA Systems Products
2
TEA Systems
OutlineOutlineOutlineOutline
• Products from TEA SystemsProducts from TEA Systems– Vector RaptorVector Raptor– Weir PWWeir PW– Weir TRWeir TR– Weir PSFM CalibrationWeir PSFM Calibration– Weir PSFM Fixed FocusWeir PSFM Fixed Focus– Weir DM and Weir DMAWeir DM and Weir DMA
• Product Features• Applications
– Addressed by each product
• System Requirements• License Basis• Sample Wafer Plots
• Products from TEA SystemsProducts from TEA Systems– Vector RaptorVector Raptor– Weir PWWeir PW– Weir TRWeir TR– Weir PSFM CalibrationWeir PSFM Calibration– Weir PSFM Fixed FocusWeir PSFM Fixed Focus– Weir DM and Weir DMAWeir DM and Weir DMA
• Product Features• Applications
– Addressed by each product
• System Requirements• License Basis• Sample Wafer Plots
2007 TEA Systems Products
3
TEA Systems
Vector RaptorVector RaptorVector RaptorVector Raptor
• Vector Raptor – Overlay Double Patterning– Classic Overlay Modeling
• Classic models WITH additional:– Graphics & control– Portability– Apply to
» whole field, row (reticle scan response) and column (scan-slit response)
– Advanced Features• Match to any other CDU metrology• Proprietary modeling engine
– Models adaptive– Multi-level, automate and manual methods for data culling
• Multi-Family Analysis– overlay-structure and pattern-split analysis
• Error Source Discrimination– Resolve error sources:
» Process» Wafer-chuck» Field» Reticle Scan» Lens Slit
2007 TEA Systems Products
4
TEA Systems
Weir PW & LithoWorks PEBWeir PW & LithoWorks PEBWeir PW & LithoWorks PEBWeir PW & LithoWorks PEB
Weir PWWeir PW• Process Windows and much more.
• Critical feature,overlay, registration,electrical and film models for simulator calibration, process setup, control and characterization
Weir TRWeir TR• Time Response based studies
•Automated Phase and energy calculation
• Post Exposure Bake and other thermal studies
• Correlate temperature data to Weir PW analyses for a true analysis of thermal uniformity.
IsoFocal Analysis
PEB Thermal Energy vs Resist
2007 TEA Systems Products
5
TEA Systems
Weir PSFMWeir PSFMWeir PSFMWeir PSFM
Weir PSFM Weir PSFM CalibrationCalibration
• Phase Shift Focus Monitor and other linear of exposure-tool focus to specialized test structures.
• Works with Benchmark PSFM, CANON Zspin, AMD Phase-Grating, ASML Focal, Toshiba Phase Gratings, End-of-Line Shortening and other reticle patterns
• Models the calibration-derived focal-plane of the exposure tool to derive reticle and tool focus budget.
Weir PSFM Weir PSFM Fixed FocusFixed Focus
• Analysis of full-field, wafer and lot focus-uniformity data.
• Use Weir PSFM Calibration templates to convert measured offset data to Focus
• Model the flatness of films, wafers, reticles, reticle scanners and lens perturbations.
PSFM Calibration
Focus Uniformity
2007 TEA Systems Products
6
TEA Systems
Weir DM & Weir DMAWeir DM & Weir DMAWeir DM & Weir DMAWeir DM & Weir DMA
Weir DMWeir DM• Daily Monitor, two-click automation
• Any Weir PW or PSFM analysis using user-created Macros
• Trend charts, password protection, graphic displays
Weir DMAWeir DMA• Daily Monitor Automated
• External program-callable Macros
• Automated alarms and output
• User selected output formats and variables
Weir DM Macro Setup Interface
2007 TEA Systems Products
7
TEA Systems
Running Weir DMRunning Weir DMRunning Weir DMRunning Weir DM
The Weir DM is a “stand-alone” program that can also be called from the Weir Engineering interface.
The analysis for a calibration uses the layout specified in the template.Current DM TemplatesCurrent DM Templates
Files in the data directory.
Sorted alphabetically.
Files in the data directory.
Sorted alphabetically.
Starts the calibration.Starts the calibration.
“One-Click”Analysis
• pre-selected templates in drop-down listings
• Data files, sorted and pre-selected in a drop-down listing.
2007 TEA Systems Products
8
TEA Systems
Astigmatism Trend Chart on Weir DMAstigmatism Trend Chart on Weir DMAstigmatism Trend Chart on Weir DMAstigmatism Trend Chart on Weir DM
• Astigmatism, also sensitive to lens heating, is shown to settle after the 8th wafer.
2007 TEA Systems Products
9
TEA Systems
Outline: Product FeaturesOutline: Product FeaturesOutline: Product FeaturesOutline: Product Features
• Products from TEA Systems• GeneralGeneral Product Features Product Features
– Data ImportData Import– Graphics FeaturesGraphics Features– 2D Graphics2D Graphics– 3D Graphics3D Graphics– General AnalysesGeneral Analyses– Data ToolsData Tools– Retention & ReportingRetention & Reporting
• Applications– As addressed by each product
• System Requirements• License Basis
• Products from TEA Systems• GeneralGeneral Product Features Product Features
– Data ImportData Import– Graphics FeaturesGraphics Features– 2D Graphics2D Graphics– 3D Graphics3D Graphics– General AnalysesGeneral Analyses– Data ToolsData Tools– Retention & ReportingRetention & Reporting
• Applications– As addressed by each product
• System Requirements• License Basis
2007 TEA Systems Products
10
TEA Systems
Data Import FeaturesData Import FeaturesData Import FeaturesData Import Features
• Import ANY metrology– If we don’t have the import
now, we will create it
• Focus-Exposure excel spreadsheets
• Overlay, film-thickness, profile, Cdsem, electrical test, etc.
• Open data format– Microsoft Excel Workbooks
• A unique Weir Workbook is created for each dataset
• Any number of variables• Any size dataset
• Weir imports data from any ASCII, Binary or database.
• After import, data is converted into a standard Weir format Excel Workbook.
• Workbook Stores– Intermediate analysis data,
– analysis reports,
– Graphics
– Derived datasets
• HTML delivery– Weir Worksheets can be
saved as HTM or HTML files for internet display
• Weir imports data from any ASCII, Binary or database.
• After import, data is converted into a standard Weir format Excel Workbook.
• Workbook Stores– Intermediate analysis data,
– analysis reports,
– Graphics
– Derived datasets
• HTML delivery– Weir Worksheets can be
saved as HTM or HTML files for internet display
2007 TEA Systems Products
11
TEA Systems
Graphics FeaturesGraphics FeaturesGraphics FeaturesGraphics Features
• Drill-down graphics• Any graphic:
– Easy user modification
• Mouse selected graphics– View sub-plots
– Save to spreadsheet data from sub-sections
– Cull specific data points/sites or areas of data.
• Single-click access to graphs, sub-graphics, data selection and culling.
2007 TEA Systems Products
12
TEA Systems
Viewing variations across wafer Viewing variations across wafer diameterdiameterViewing variations across wafer Viewing variations across wafer diameterdiameter
• Use mouse to drag and outline a section.
• Plot graphic by x column position
• Notice astigmatism and how it increases at wafer’s edge.
Xfocus
Yfocus and
Average
2007 TEA Systems Products
13
TEA Systems
Graph EditorGraph EditorGraph EditorGraph Editor
Graphic interface modification
Point-click adjustments
Graphs are mouse sensitive to show and highlight individual points
2007 TEA Systems Products
14
TEA Systems
2D Graphs2D Graphs2D Graphs2D Graphs
• Histograms– 1 & 2 variable
• XY Plots– Line and scatter plots– BoxPlots, Fitted Curves and notes
can be added to any plot
• BoxPlots– Can be added to ANY XY plot
• Population Density Plots• Field & Wafer Contour• Radial Variation • Range Plots• 1D and 2D Vector Plots• Variable Covariance plots• Plus all Excel –based graphics
Raw Photoresist Thickness from Ellipsometer
2007 TEA Systems Products
15
TEA Systems
3D Graphs3D Graphs3D Graphs3D Graphs
• Field 3D surface graphics• General response surface
graphics
2007 TEA Systems Products
16
TEA Systems
General AnalysesGeneral AnalysesGeneral AnalysesGeneral Analyses
• Plots and statistics– For Raw, Modeled and Residual data.
• Reticle data at true(4x) and final (1x) size– Mask Error Function (MEF) plotting– Removal of Reticle data from wafer for true process
response
• Optimum or “Best Focus”– From PSFM and other specialty reticles– From variable Feature profiles for reticle design &
simulator validation
• Automated Precision & Error Budget calculation• Automated variable Covariance
2007 TEA Systems Products
17
TEA Systems
Data ToolsData ToolsData ToolsData Tools
• View raw, modeled and residual data• Model any wafer, field,lens, slit and scan systematic errors
– For any variable– View individual wafer, field, slit,etc modeled, residual data
• Multiple field models– Weir custom and scanner vendor emulated
• View data as astigmatic, average, max/min data variations.– Field Mean, max, minimum, MinMax, IFD, Range MEF etc.
• Stepper as well as scanner oriented models– Also hotplate, etch symmetric and asymmetric models
• Exposure Layouts– Across wafer & Lot variations for Focus, Dose, Numeric Aperture,
Partial Coherence, Scan Direction are stored with data.– Layouts can be imported from the data– Graphic, mouse-driven utility for easy manual entry of the layout– Layout library is maintained for easy updating of new datasets with a
single click of the mouse
2007 TEA Systems Products
18
TEA Systems
Data RetentionData RetentionData RetentionData Retention
• Data is imported and stored in an open format– Easily adapted to other software analyses or user analysis
using Excel – native tools
• Data is stored in the same workbook for:– Raw data– Recipe and measurement notes– Site locations– Analysis reports and graphics– All intermediate modeling surfaces– All calculated data surface
2007 TEA Systems Products
19
TEA Systems
Outline: ApplicationsOutline: ApplicationsOutline: ApplicationsOutline: Applications
• Products from TEA Systems• Product Features• Applications (Automated by Weir DMA)
– Overlay– Exposure Tool setup & Characterization– Photomask Process Control– Reticle RET Qualification– Thermal Process setup– Metrology validation – LER, ARC and Resist evaluation– Process Setup & Control– Modeled Production Gating– Simulation validation– Focus optimization
• System Requirements• License Basis
• Products from TEA Systems• Product Features• Applications (Automated by Weir DMA)
– Overlay– Exposure Tool setup & Characterization– Photomask Process Control– Reticle RET Qualification– Thermal Process setup– Metrology validation – LER, ARC and Resist evaluation– Process Setup & Control– Modeled Production Gating– Simulation validation– Focus optimization
• System Requirements• License Basis
2007 TEA Systems Products
20
TEA Systems
Exposure Tool Setup & CharacterizationExposure Tool Setup & CharacterizationExposure Tool Setup & CharacterizationExposure Tool Setup & Characterization
• Weir PW – spatial feature & process window models– Calculate component precision and their
contributions to feature distortion.– Remove reticle & average field data
• enhanced exposure tuning and scan-and-slit performance mapping.
– Classic lens aberrations • and their influence on feature size.
– Classic process windows PLUS • Across entire field for any number of variables.
– Model Films, BARC, TARC, swing curve etc. behavior
– Wafer-edge and field-edge aberrations.– Scan region sensitivity– Dose Uniformity– Derive Reticle sizes from wafer data– Lens and reticle heating during exposure.– Map DoF uniformity – Simulate tool performance “What if”
• Weir PSFM (Focus)– Map aerial image, focal plane uniformity
– Model whole–wafer autofocus stability
– Map wafer flatness and derive the influence of substrate films on autofocus sensitivity.
– Model lens-slit and reticle-scan static and dynamic performance signatures.
– Extract wafer-edge and edge-bead effects.
– Calculate classic lens aberrations through their influence on feature focus.
2007 TEA Systems Products
21
TEA Systems
BottomCD vs FocusBottomCD vs FocusBottomCD vs FocusBottomCD vs Focus
Up + SCAN
Down - SCAN
Scanner AScanner "B"
Isofocal region on Scanner A vs B
2007 TEA Systems Products
22
TEA Systems
Photomask Process ControlPhotomask Process ControlPhotomask Process ControlPhotomask Process Control
• Weir PW– Metrology from any data source or manual entry– Process Windows, Bossung Plots etc.– Model etch uniformity from scatterometry– Model feature profiles and etch depth
• Correlate to wafer response across the process window
– Encapsulate data • standard format for the wafer-fabrication engineer
• Provides a valuable commodity by giving the wafer engineer a reticle signature library entry for:
– Reticle design qualification– Reticle use re-validation– Wafer process setup thru reticle signature removal– Tool setup for thermal bake and exposure-tool reticle bending
2007 TEA Systems Products
23
TEA Systems
MoSiON FingerprintMoSiON FingerprintMoSiON FingerprintMoSiON Fingerprint
• MoSiON uniformity across Reticle– 1D vector plot (top left)– Contour (top right) – 3D Contour bottom left
2007 TEA Systems Products
24
TEA Systems
Reticle RET QualificationReticle RET QualificationReticle RET QualificationReticle RET Qualification
• Qualify Reticle Enhancement Techniques• Weir PWWeir PW
– Use Focus or Focus-Dose Matrices– Calculate true reticle size
• Weir automatically removes wafer, film and focus errors as well as dose perturbations
• Sub-nanometer accuracy from CDsem or Scatterometry• Works with all RET methods
– Correlate to measured reticle variables• Optimize reticle etch depth for RET
– Calculate Depth-of-Focus uniformity for each scanner/stepper
– Calculate Best Focus for this RET design– Qualify simulator responses – Determine simulator variable values
Reticle signature and damaged site
2007 TEA Systems Products
25
TEA SystemsCD-SEM ReticleMEF+ = 4.3292
Optimized BCD from Wafer
Nanometrics ReticleMEF+ = 4.305813
Calculated & measured Reticle SizeCalculated & measured Reticle SizeCalculated & measured Reticle SizeCalculated & measured Reticle Size
2007 TEA Systems Products
26
TEA Systems
Thermal Process setupThermal Process setupThermal Process setupThermal Process setup
• Weir TR - PEB Setup– Import Thermal probe data from
any commercial system– Visualize and model thermal flow,
cycles, uniformity.– Calculate energy delivered to
segments of the substrate.– Align and correlate thermal
energy and model data to spatial models of critical feature elements across the wafer and bake plate.
• Weir PW– Correlate wafer-spatial model
response to thermal response variables LithoWorks PEB
Thermal Probe Plot
2007 TEA Systems Products
27
TEA Systems
PEB 7; Thermal energy variationPEB 7; Thermal energy variationPEB 7; Thermal energy variationPEB 7; Thermal energy variation
• Energy variation around the average temperature.
• Represents the area “under the curve”– Variations below
the mean wafer temperature at each slice are considered negative (deg-sec)
– Right side of wafer receives less themal energy
2007 TEA Systems Products
28
TEA Systems
Thermal range and transitions: PEB 8Thermal range and transitions: PEB 8Thermal range and transitions: PEB 8Thermal range and transitions: PEB 8
PEB 8Rise/Fall TimesStart Time Start TempRise Delta Time Delta TempSlope
28.9700 23.5100 TRUE 21.6000 91.8200 4.2509134.0400 117.6600 FALSE 28.4800 -88.5600 -3.1095
PEB 7Rise/Fall TimesStart Time Start TempRise Delta Time Delta TempSlope
27.0000 23.4200 TRUE 21.6100 91.1800 4.2193132.5700 117.3500 FALSE 28.4800 -88.1000 -3.0934
2007 TEA Systems Products
29
TEA Systems
Bake versus Feature correlationsBake versus Feature correlationsBake versus Feature correlationsBake versus Feature correlations
Photoresist Thickness
2007 TEA Systems Products
30
TEA Systems
Metrology validationMetrology validationMetrology validationMetrology validation
• Weir PW– Validate scatterometry model range and repeatability– Calculate metrology tool precision– Determine the limits of metrology tool variation
2007 TEA Systems Products
31
TEA Systems
Metrology: Variable CovarianceMetrology: Variable CovarianceMetrology: Variable CovarianceMetrology: Variable Covariance
• Understanding the covariance of thresholds and measured values is critical.
• Below is a covariance matrix of multiple features measured in the data set.
• The plot shows the covariance of two selected variables
• Graph selections are easily made using the drop-down and check-boxes provided.
Top & bottom die sites
2007 TEA Systems Products
32
TEA Systems
LER, ARC and Resist evaluationLER, ARC and Resist evaluationLER, ARC and Resist evaluationLER, ARC and Resist evaluation
• Weir PW– Use with 4-point probe, electrical or scatterometry data– Calculate swing curves from normal product data or
focus–dose matrices– LER from any CDsem or other linewidth tool
• mapped to wafer/field position
• Calculate covariance with other metrology variables
– ARC thickness and Photoresist optimization• Bottom or Top ARC’s
• Determine thickness changes with focus/dose
• Calculate changes in optimum focus with ARC type and dose
• Compare to other brands for process window, influence on DoF, optimum focus etc.
2007 TEA Systems Products
33
TEA Systems
Process Setup & ControlProcess Setup & ControlProcess Setup & ControlProcess Setup & Control
• Weir PW – Standard Process Windows
• Independent / simultaneous rectangular and elliptical windows
– Full-field process window models• Needed for sub-90 nm nodes• Any number of features and field-sites.
– Full-field Depth-of-Focus– Removal of wafer tilt and bow prior to
modeling– User and automated data culling – Swing curve fitting from production or dose
matrix data sets.– Thickness-loss curve fitting – Film uniformity monitors – Visual, whole-wafer and whole field mapping
of process window.– Wafer radial and edge-bead analysis.– Exposure tool dose uniformity evaluations.
• Weir PSFM– Aerial Image, full-field and
wafer focus modeling– Flatness & Tilt control
• Only software capable of calculating wafer tilt
– Focus uniformity– Edge influence on auto-
leveling and auto-focus– Edge bead analysis
2007 TEA Systems Products
34
TEA Systems
Scatterometry Process WindowScatterometry Process WindowScatterometry Process WindowScatterometry Process Window
Dose= 18 19 20 21 22 23 24
Focus-0.24
-0.16
-0.08
0.0
+0.08
+0.16
+0.24
Process Window
• Exposures• 193nm litho process for 100nm
features– AT1100 scanner, 0.75NA with annular
illumination– 90nm gratings at 1:1 with full field
coverage– 240nm resist on 78nm Barc on Si
• OCD metrology: NI, rotating polarized light (Nano9030)
• diffractive optical metrology (scatterometry) - outputs spectral intensity changes of 0th order diffracted light intensity
Weir PW Software from TEA Systems
2007 TEA Systems Products
35
TEA Systems
Metrology & Process Independent Metrology & Process Independent CharacteristicsCharacteristicsMetrology & Process Independent Metrology & Process Independent CharacteristicsCharacteristics
Focus Uniformity
Depth of Focus Uniformity
2007 TEA Systems Products
36
TEA Systems
Process Window Setup InterfaceProcess Window Setup InterfaceProcess Window Setup InterfaceProcess Window Setup Interface
2007 TEA Systems Products
37
TEA Systems
Process Window - center of fieldProcess Window - center of fieldProcess Window - center of fieldProcess Window - center of field
2007 TEA Systems Products
38
TEA Systems
Spatial comparison of parametersSpatial comparison of parametersSpatial comparison of parametersSpatial comparison of parameters
• Examine and compare systematic variations across the wafer
• Provides information of process sensitivity
• Systematic errors can be removed from data to enhance analysis resolution.
• Data shown as 1D vector & contour plot (lower right)
SWA
PResist thickness
CD Threshold
ARC Coat
SWA v Wafer Radius
2007 TEA Systems Products
39
TEA Systems
Dose @ Best FocusDose @ Best FocusDose @ Best FocusDose @ Best Focus
Feature Site Dose Focus CD Feature Dose Site Best FocusBCD (nm) 5 16 0.161 138.9701 BCD (nm) 16 5 0.161BCD (nm) 5 17 0.169 125.7164 BCD (nm) 17 5 0.169BCD (nm) 5 18 0.173 112.4759 BCD (nm) 18 5 0.173BCD (nm) 5 19 0.176 99.2418 BCD (nm) 19 5 0.176BCD (nm) 5 20 0.178 86.0113 BCD (nm) 20 5 0.178BCD (nm) 5 21 0.179 72.7831 BCD (nm) 21 5 0.179BCD (nm) 5 22 0.181 59.5564 BCD (nm) 22 5 0.181
2007 TEA Systems Products
40
TEA Systems
Report Dose @ Best FocusReport Dose @ Best FocusReport Dose @ Best FocusReport Dose @ Best Focus
BCD (nm), : vs Dose @ Best Focus
Field Sites:One Site #: 5,Variable TCL UCL LCLBCD (nm) 100.0000 105.0000 95.0000
Summary:BestDose DoseRangeBestFocus FocusRangeDose_%LatitudeDose_%LatitudeRangeDoF DoF_Range
18.9000 0.0000 0.1760 0.0000 4.0000 0.0000 0.0020 0.0000
Summary by FeatureFeature BestDose DoseRangeBestFocus FocusRangeDose_%LatitudeDose_%LatitudeRangeDoF DoF_RangeBCD (nm) 18.9000 0.0000 0.1760 0.0000 4.0000 0.0000 0.0020 0.0000
Summary by Site: Dose Response at Optimum FocusVariable Site BestDose EL% BestFocus DoF UCL_dose LCL_dose UCL_focus LCL_focus Fit EquationBCD (nm) 5.0000 18.9000 4.0000 0.1760 0.0020 18.6000 19.3000 0.1750 0.1770 BCD (nm)=351.576 - 13.327 * x + 0.002 * x ^2
Portion of a Weir Data Workbook report on BCD vs Dose response when Focus errors are removed
2007 TEA Systems Products
41
TEA Systems
Modeled Production GatingModeled Production GatingModeled Production GatingModeled Production Gating
• Weir PW– Model profile variation across the field and wafer– Pass/fail wafers for redo loops or control based on
modeled results• Results in fewer wafers rejected when compared to “mean+3
sigma” gating tests
– Model film thickness, profiles, Side-wall-angle (SWA), CD size, etc.
2007 TEA Systems Products
42
TEA Systems
Simulation validationSimulation validationSimulation validationSimulation validation
• Weir PW– Evaluate film thickness and feature profiles– Correlate data with outputs from Prolith, Sigma C etc.– Calculate simulator variables to improve simulations– Determine influence of the full process window on
simulators
2007 TEA Systems Products
43
TEA Systems
Focus optimizationFocus optimizationFocus optimizationFocus optimization
• Weir PW– Derive focus and dose uniformity
• from feature focus-matrices and line-end-shortening.
– Calculate "Best Focus" across field (IFD) and Focal-plane uniformity
• from any Critical Feature metrology set, Line-End-Shortening
– Determine Dose response from focus-error-free data
• Weir PSFM– Calibrate Phase Shift Focus Monitor (PSFM), Phase
Grating( PGM), End-of-Line, and Z-spin Reticles.– Apply reticle calibrations to whole-wafer focus uniformity
analyses.– Calculate both wafer and field tilt, bow and random errors– Calculate the effects of thermal heating during exposure– Effects of film, trench-etch, wafer and and scanner stage– Wafer edge-bead and edge-die influence– Measure wafer flatness.– Analyze ASML FOCAL focus data
• with raw or modeled full-field analyses
2007 TEA Systems Products
44
TEA Systems
Focus Slit ProfileFocus Slit ProfileFocus Slit ProfileFocus Slit Profile
• Focus uniformity across lens (slit)• Field-modeled piston and tilt have been removed.
PGM PSFM160 PSFM180FOCAL
2007 TEA Systems Products
45
TEA Systems
X-Slit AstigmatismX-Slit AstigmatismX-Slit AstigmatismX-Slit Astigmatism
Z5
-10
-8
-6
-4
-2
0
2
4
6
8
10
-15 -10 -5 0 5 10 15
Artemis (from 3/2002) Annular (0.85/0.55)
PGM
FOCAL
PSFM 180
PSFM 160
• Shape of curve for Z5 Artemis coefficient and the Focal Astigmatism plot is good
– Field tilt is included in the FOCAL data• Magnitude of the plots is off• Also recall that the FOCAL data is from a ring-aperture setting.
2007 TEA Systems Products
46
TEA Systems
Tool Programmed OffsetsTool Programmed OffsetsTool Programmed OffsetsTool Programmed Offsets
• “Mean” focus is plotted
• Tool focus set to –0.1– Median effective
focus = -0.028
• Offsets follow programmed values (above) very closely.
– -0.24 field is shown by arrow for orientation
Background focus, no offsets
2007 TEA Systems Products
47
TEA Systems
Relative Measured Field OffsetsRelative Measured Field OffsetsRelative Measured Field OffsetsRelative Measured Field Offsets
• Restricted analysis wafer diameter to 85 mm radius
• Removed mean field• Relative offsets of each field is
clearer
2007 TEA Systems Products
48
TEA Systems
Recommended System RequirementsRecommended System RequirementsRecommended System RequirementsRecommended System Requirements
• Minimum recommended system:– Windows 2000 or XP Professional– Microsoft Excel version 9 or later– Pentium IV, 1.2 Gigahertz CPU– 256 Megabytes of RAM– Monitor 1024x780
2007 TEA Systems Products
49
TEA Systems
License BasisLicense BasisLicense BasisLicense Basis
• License formats– Licenses are software locks that are keyed to the hardware upon
which it is installed.– Licenses can be input manually or delivered via email text files.– License periods can be set from 1 to 365 days or as a permanent
license– Demonstration, lease and permanent licenses are available.
• Single-user node-locked license– License is locked to a computer’s disk– Only one user, on the target computer may use the license
• Floating node license– License is locked to a computer’s disk– Any user on the network can access and use the software– Only one user at a time may use the software– Software image shuts-down after 30 minutes of non-use
• Thereby freeing the license for the next user.
2007 TEA Systems Products
50
TEA Systems
Summary of Weir PWSummary of Weir PWSummary of Weir PWSummary of Weir PW
• Any metrology data can be imported– Weir PW contains a layout optimizer and basic metrology analysis capabilities– Any user-defined variable names may be used– Data is stored in Microsoft Excel® worksheet and workbooks
• Multiple data sets can be combined and data sub-sets selected for analysis– Point-and-click mouse interaction for data viewing and culling
• “Metrology” analysis– Automated metrology covariance– Automated error-budget analysis.
• Spatial analysis of variables– Provides information on variation with scan direction and film thickness variation– Point-and-click drill down capability for sub-field graphics, data viewing and analysis– Remove critical systematic components to see the true exposure performance
• Process Window analysis and more!– Extend beyond the single feature/family analysis.– Examine process window performance variation across the full field of exposure.
• Automation– Weir DM can be used to automate process-monitor points for any variable series.
2007 TEA Systems Products
51
TEA Systems
Extra Wafer Maps of 6Extra Wafer Maps of 6thth order order parameter variationparameter variation
(next section)(next section)
Extra Wafer Maps of 6Extra Wafer Maps of 6thth order order parameter variationparameter variation
(next section)(next section)
These slides illustrate the variation of measured feature size across the wafer and field. More importantly, they illustrate that feature sizes can be modeled as systematic errors across each.
Note that when these systematic errors are removed, the residuals track the variation of underlying film thickness (such as.anti-reflective coatings) and thermal-variation (Post Exposure Bake) across the wafer during processing. Slide 34 is a good example.
Weir therefore provides a direct method of measuring both feature and film-variation influence on feature size.
2007 TEA Systems Products
52
TEA Systems
PhotoresistPhotoresistPhotoresistPhotoresist
All terms 4th & 6th only Residuals to all terms
2007 TEA Systems Products
53
TEA Systems
ARCARCARCARC
Residuals to Wafer ModelMean Field Removed
Wafer Model Residuals to all Wafer Coefs
2007 TEA Systems Products
54
TEA Systems
CD 95% ThresholdCD 95% ThresholdCD 95% ThresholdCD 95% Threshold
Wafer model; 4th & 6th order only
Wafer Model Residuals to Wafer Model; mean field
removed.
2007 TEA Systems Products
55
TEA Systems
SWASWASWASWA