Terrence E. Zavecz TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp. Vector Raptor Overlay Analysis for Double Patterning & Beyond Preview Presentation of basic features & applications User-customized models Drill-down graphics Precision Analysis Covariance Analysis Five levels of manual & automated data culling Multi-layer, Multi-variable lot analysis Engineering Analyses can be “one-click” automated using Weir Daily Monitor Scripts Remote program automation & calling June 6, 2007

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Advanced Overlay Analysis & Modeling Model raw data for each structure separately Remove outliers by using the model  Use at most a second order polynomial?  Use 3 sigma or the range from the population median as a control threshold Agenda  Interface Overview  Spatial model generation & graphics  “What-if” scenario  Graph generation using mouse selection  Vector Raptor Excel Workbook Data Storage  Data Storage Organization  Example Reports  Interactive graph customization  Radial Wafer Analysis & Radial Culling  Multi-Pattern Lot Splits (Families)  Results by family  Reports & mouse generated graphics  Model Editor Vector Raptor

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Concept Vector Raptor; Classic Overlay Modeling  Employs all classic models for stepper & scanners  WITH additional sophistication in:  Graphics & control  Analysis  Portability  Results reporting  Ability to apply models to whole field, row (reticle scan response) and column (scan-slit response) Advanced Features  Proprietary modeling engine using adaptive model elements and singular value decomposition  Models adaptive to both singularities and fit-culling  Multi-level, automate and manual methods for data culling  Multi-Family Analysis  For true overlay-structure and pattern-split analysis  Error Source Discrimination  Ability to resolve error sources from between:  Process  Wafer-chuck  Field  Reticle Scan  Lens Slit

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Poly DP Solution 193i – 1.2 NA X-Y Polarized light K1 = 0.28 Pitch 90 nm Double Patterning (DP) is a split of the pattern layers to provide sub-0.45 nm lithograph Double Patterning can actually be more than two splits Situations are envisioned of up to five (5) patterned splits that must each undergo multiple alignment, exposure, develop deposition and etch steps.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Double Patterning Concepts “Double Patterning”  Actually adds multiple alignment and process levels for each split Mask Critical  Overall mask registration errors will be critical:  Alignment accuracy to scanner registration marks for the layer  Overall mask magnification, uniformity, rotation and skew will become more critical  Processing  Variations in processing can influence not on CD size but the mask response to lens aberrations when wafer is exposed  Greater or less sensitivity to variation in focus, polarization and dose Process Critical  Alignment sensitivity of the scanner to the registration on the mask  Mask bow/distortion while mask is chucked varies from scanner to scanner  Overlay distortion across a single field is now sensitive to lens-placement distortions from tool response to Dose and deFocus  Problems will exist in trying to understand the sources of these overlay errors due as they vary across the finished device layer.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Vector Raptor Interface Vector Raptor is an engineering interface  May be used with Weir DM for script automation of any engineering analysis Data  Data is stored in the TEA Standard metrology format  Microsoft Excel Workbooks are used for data storage  “VR Workbooks”  Any metrology may be imported and stored into VR Workbooks Reports etc.  All reports, analyses and extractions are stored in the VR data workbook. Microsoft Windows  XP, 2000, 2004 Server etc.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Vector Raptor Button Bar Model Editor  Create and/or modify substrate and field surface models Layout Editor  Enter exposure information for each die including focus, dose, NA, Sigma and reticle scan direction  Adjust wafer size, die size, offset, notch etc. Active Workbook  By default this is the metrology data workbook  Analyses and modeling generate additional data that can also be analyzed and graphed Import Metrology Data Load Workbook Data Print screen View current data in workbook format Copy Screen Copy Graphic only Model Editor Layout Editor Variable Under Analysis Family Member Selection Active data worksheet in workbook

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Loading Data With Vector Raptor  Load RV Workbooks directly  Import any metrology data  Drag & drop any ASCII or workbook into the interface With Daily Monitor analysis using Vector Raptor models & methods  Load data directly  Drag & drop  Load data, and start analysis, using calls from external programs Drag & drop with mouse Data Import

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Data Selection & culling Field Layout Wafer Layout “Field Sites” data sheet Exposure Subset Selection for: Wafer Focus Dose Reticle Scan direction NA Partial Coherence (Sigma) Exposure Subset Selection for: Wafer Focus Dose Reticle Scan direction NA Partial Coherence (Sigma) Data culling by variable range ‘one-click’ histogram for range selection aid

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Data Culling & Sub-Set Plotting Box-in any set of data during selection  With ‘wafer’ you can plot or cull individual data points  With the ‘field’ plot on left, you can remove selected ‘sites’ on the field Mouse-box

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Spatial Models Raw Data analysis of wafer & field  Mouse-sensitive data viewing/graphing Histogram of corner site data Created by boxing in site with mouse

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Contour & 3D plots

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp D Vector Plots

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer & Field Modeled results Apply models as needed Perform “What-if” scenarios for terms Colored vector-amplitude can be switched off

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp “What-if” Scenarios Left – full-field model  Each field individually modeled & results plotted Right- response with “Piston” or the “offset” removed. Note: for this example the field model used here is a simple A +Bx –Cy –DX 2 –EY 2 And does not represent any valid overlay model. For demo purposes only

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Scale change Vector-scale, as shown or Magnitude bar-scale can be changed independently

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Graph Generation using mouse Mouse hovered over point to see data value Use mouse to graph, delete or spreadsheet-view a section of data

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Interactive Index Sheet for data workbook

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Detailed field-by-field aberrations

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Response Report

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Graph interface for customization XY line graphs can also  Create box-plots  Population-density plots  Fit general polynomial trend- lines  Add comments & messages  Rescale with the mouse or by this interface  Etc.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Sites with “split” families

Terrence E. Zavecz TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp. Radial Wafer Analysis & Radial Culling

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Cull Radius control Data sets of over 22,000 data sites have been measured

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Radial Analysis Press the “cull radius” command button Screen appears Graphic & report generated

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Population response for Range & Sigma Cull Compares multiple “family’s” or pattern-splits Only one shown here

Terrence E. Zavecz TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp. Multi-Pattern Lot Splits (Families) Lot contains data with three (3) overlay splits Splits are defined in the single data file as different site family values.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Model This summarizes all splits

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Results by family Graphs are automatically created Fitted Range of values

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Fitted Reports Focus and Dose response can also be evaluated

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Modeled X & Y overlay split response across wafer Response across wafer

Terrence E. Zavecz TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp. Model Editor Vector Raptor comes with standard ASML, Nikon and CANON models User customization and model additions are performed using the Model Editor

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Models Editor

Terrence E. Zavecz TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp. Precision & Covariance

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Overlay Precision Analysis

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Covariance Covariance chart in workbook shown

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp X-Y Covariance plot First order fitted line (red) and fit-polynomial message added by graph editor

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp U7 Overlay wafer & field model

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer model Wafer offset not included

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer (Process) Modeled Errors

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Component

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Mag, rotation & trap

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Mag, Rot & Trap

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp After data point removal 14,861 data points ASML XT1400 XYSMO data

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp X & Y Overlay X and Y overlay Note center-of-wafer “hot” spot

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Model Editor Any number of sequential models Model coefficients are summarized into one algorithm for each sub-model Coefficient Control Area Display name is used in reports Units-of-measure Select from drop-down or enter any format such as “nm/cm2” or “ergs/mm2” or ppm etc. Equation can use any format with variables “X,Y,R and Theta” Threshold = number of points that must be in the data to use this coefficient Control bar allows individual coefficient to be created, copied, pasted, deleted or moved up/down in the analysis. This analysis shows three wafer-based models available for analysis from the library. User can add/delete models Field models can be seen if the user clicks on the field

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Excluded data points Registration/overlay data excluded by ASML.

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer Model

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer Residuals

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Field Residuals

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Fitted Field values

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Full field model, trap & wedge contribution Note that lower row on each field is changing X direction Noise in scan-start/end

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp X-Reg, Trapezoid & Wedge Wafer #1Wafer #2Wafer #3

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Xreg, Trap2 (X*Y)

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer #2 Fitted errors without offset

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer #2, Trapezoid

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Wafer #2, field rotation

Yield Enhancement thru Modeling TEA Systems TEA Systems Confidential & Proprietary Copyright © 2007 TEA Systems Corp Fitted Double - Pattern Overlay Field & Lens Slit Rotation Component Modeled X-Registration for Trap & Wedge