On the cover (top to bottom): Joseph Hodges operating frequency-stabilized cavity ring-down spectroscopy (CRDS) for measuring very low concentration contaminants in process gases. Time-resolved vertical distribution of optical emission at 750nm from a dual-frequency capacitively-coupled plasma. Critical Dimension Small Angle X-Ray Scattering (CD-SAXS) detector image resulting from a dense array of 60 nm vias. Curt Richter loads a molecular electronic sample for electrical characterization. Photo copyright Robert Rathe. SEMICONDUCTOR MICROELECTRONICS AND NANOELECTRONICS PROGRAMS NISTIR 7426 July 2007 U.S. DEPARTMENT OF COMMERCE Carlos M. Gutierrez, Secretary Technology Administration Robert Cresanti, Under Secretary of Commerce for Technology National Institute of Standards and Technology William Jeffrey, Director DISCLAIMER Disclaimer: Certain commercial equipment and/or software are identifi ed in this report to adequately describe the experimental procedure. Such identifi cation does not imply recom- mendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the equipment and/or software identifi ed is necessarily the best available for the purpose. References: References made to the International Technology Roadmap for Semiconductors (ITRS) apply to the most recent edition, dated 2005 or the ITRS 2006 Update. Semiconductor Industry Association. The International Technology Roadmap for Semicon- ductors, 2005 edition. SEMATECH: Austin, TX, 2005. These documents are available on-line at URL: http://public.itrs.net or in printed copy by contacting SEMATECH, 2706 Montopolis Drive, Austin, TX 78741, ITRS department 860-008, phone: (512) 356-3500. The reader will notice that there are acronyms and abbreviations throughout this document that are not spelled out due to space limitations. We have listed the acronyms and abbrevia- tions in an appendix at the end of this document. CONTENTS Welcome and Introduction ....................................................................................................v Offi ce of Microelectronics Programs Organization ............................................................vii Lithography Metrology Program ......................................................................................1 Metrology Supporting Deep Ultraviolet Lithography ..........................................................3 Metrology Supporting Extreme Ultraviolet Lithography .....................................................7 Polymer Photoresist Fundamentals for Next-Generation Lithography ..............................13 Critical Dimension and Overlay Metrology Program ...................................................19 Wafer-Level and Mask Critical Dimension Metrology ......................................................20 Model-Based Linewidth Metrology .............................................................................21 Scanning Electron Microscope-Based Dimensional Metrology ..................................25 Scanning Probe Microscope-Based Dimensional Metrology ......................................31 Optical-Based Photomask Dimensional Metrology .....................................................37 Scatterometry-Based Dimensional Metrology ............................................................41 Small Angle X-Ray Scattering-Based Dimensional Metrology ...................................45 Dimensional Metrology with Grazing Incident X-Ray Scattering ..............................49 Atom-Based Dimensional Metrology ..........................................................................51 Fabrication and Calibration Metrology for Single-Crystal CD Reference Materials ..57 Wafer-Level and Overlay Metrology ..................................................................................63 Front-End Processing Metrology Program ....................................................................69 Wafer and Chuck Flatness Metrology ................................................................................71 Modeling, Measurements, and Standards for Wafer Surface Inspection ............................75 Front-End Materials Characterization .................................................................................79 Plasma Process Metrology ..................................................................................................89 Interconnect and Packaging Metrology Program ..........................................................93 Atomic Layer Deposition – Process Models and Metrology ..............................................95 Advanced Nanoscale and Mesoscale Interconnects ........................................................101 Nanoporous Thin-Film Metrology for Low-κ Dielectric Materials..................................105 Interconnect Materials and Reliability Metrology ............................................................110 Basic Materials Properties ..........................................................................................111 Test Structures For Interconnect Metrology and Modeling ....................................... 119 Pb-Free Surface Finishes for Electronic Components: Sn Whisker Growth ....................125 Process Metrology Program ...........................................................................................129 Gas Property Data and Flow Standards for Improved Gas Delivery Systems .................131 Low Concentration of Humidity Standards ......................................................................135 Temperature Measurements and Standards for Semiconductor Processing .....................141 Physical Properties of Liquid Precursors ..........................................................................145 Semiconductor Microelectronics and Nanoelectronics Programs iii Analysis Tools and Techniques Program ......................................................................147 Thin-Film X-Ray Metrology for Microelectronics ...........................................................149 Electron Microscope Tomography of Electronic Materials ..............................................155 High-Resolution Microcalorimeter X-Ray Spectrometer for Chemical Analysis ............157 Device Design and Characterization Program .............................................................163 Device Characterization and Reliability ...........................................................................165 Nanoelectronic Device Metrology ....................................................................................169 Power Semiconductor Device Metrology ........................................................................179 Organic Electronics Metrology .........................................................................................185 Micro- and Nano-Electro-Mechanical Technology Metrology ........................................189 NIST’s Center for Nanoscale Science and Technology Nanofab ....................................195 Metrology for Spintronic Devices ....................................................................................197 BioElectronics Metrology .................................................................................................203 System Design and Test Metrology Program ...............................................................207 Metrology for System-on-a-Chip (SoC) ...........................................................................209 At-Speed Test of Digital Integrated Circuits .....................................................................215 Thermal Measurements and Packaging Reliability .........................................................219 Manufacturing Support Program .................................................................................227 Factory Time Synchronization Standards Development for E-Manufacturing ................229 E-Diagnostics Security ......................................................................................................233 Engineering Chain Management in the Semiconductor Industry .....................................235 NIST/SEMATECH e-Handbook of Statistical Methods ...................................................237 Abbreviations and Acronyms .........................................................................................239 Technical Contacts ..........................................................................................................242 iv National Institute of Standards and Technology WELCOME AND INTRODUCTION WELCOME The microelectronics industry supplies vital components to the electronics industry and to the U.S. economy, enabling rapid improvements in productivity and in new high technology growth industries such as electronic commerce and biotechnology. The National Institute of Standards and Technology, NIST, in fulfi lling its mission of strengthening the U.S. economy, works with industry to develop and apply technology, measurements and standards; and ap- plies substantial efforts on behalf of the semiconductor industry and its infrastructure. This report describes the many projects being conducted at NIST that constitute that effort. HISTORICAL PERSPECTIVE NIST’s predecessor, the National Bureau of Standards (NBS), began work in the mid-1950s to meet the measurement needs of the infant semiconductor industry. While this was initially focused on transistor applications in other government agencies, in the early 1960s the Bureau sought industry guidance from