Cleanroom

Metrology

Metrology—the exacting science of measurement for process control—is crucial to the advancement of semiconductor manufacturing. Accordingly, metrology faces some of the most demanding challenges in its history as the chip industry progresses into the nanoscale and toward the limits of physical laws. Areas of particular concern include advanced patterning for lithography, new transistor structures and materials, and the effects of measurement on the processes themselves.

SEMATECH and our R&D partners operate a robust metrology program oriented to both near-term manufacturing and next-generation technology development. Its success will allow measurement science to enable the indispensable advances in lithography, materials and interconnects that in turn will push semiconductor evolution continuously forward.

Advanced Metrology

SEMATECH’s Lithography, Front End Processes, and 3D Interconnect Divisions work closely with the College of Nanoscale Science and Engineering (CNSE) of the University at Albany on advanced metrology to prepare the industry for entry into future technology generations. These projects involve reference metrology and development of disruptive (game-changing) technologies.

Supplier involvement is essential to this effort. Technologists from SEMATECH and CNSE work closely with some of the industry’s top equipment companies in developing critical tools for advanced metrology. Examples include:

  • A project with Oregon-based FEI Company to develop a transmission electron microscope (TEM) utilizing electron energy loss spectroscopy (EELS) with focused ion beam (FIB) for measuring defects in semiconductor devices. TEM-EELS-FIB is the leading candidate to replace the current technology, scanning electron microscopy (SEM) with energy-dispersive X-ray, for analyzing defects at 45 nm or below.
  • An effort with Veeco Instruments of Plainview, NY to compile a reference metrology system for critical dimension (CD), depth, overlay, and 3D applications at the 45 nm, 32 nm, and (where possible) 22 nm technology generations.
  • A joint-development agreement with Xidex, an Austin, Texas company, to develop carbon nanotube-tipped cantilevers for atomic force microscopes, to allow high resolution mapping of dopant profiles, work function variation, and dielectric damage.

Complementing these projects are CNSE’s Innovations Labs, whose work includes development of advanced optical metrology for nanoscale high-k materials, new X-ray techniques such grazing incidence X-ray diffraction (GIXD) and charged particle metrology, including the use of ion beams for materials analysis.

Manufacturing-focused Metrology

International SEMATECH Manufacturing Initiative (ISMI) focuses on tool and technology evaluations and overall factory integration with the goal of establishing a world-class industry collaborative program of metrology for advanced manufacturing. Specific areas of focus include:

  • Defect metrology - seeks to develop defect standards and assess limits and extendibility of tools for patterned and unpatterned wafer inspection, bevel edge inspection, and defect review and characterization. This program works with suppliers to develop solutions for manufacturing deployment of tools and systems.
  • Films metrology - focuses on measurements pertaining to low-k dielectric films, in-line workfunction, and tool evaluations for strain technology. Particular challenges lie in developing metrology for highly technical areas such as gate space profile, enhanced mobility devices, and non-destructive probes for measuring very sensitive surfaces.
  • Critical dimension (CD) metrology - enables the effectiveness of fine-tuning processes such as optical proximity correction and 3D structures
  • Overlay metrology - enhances engineers’ ability to align one layer over another in multi-layer device structures. Precise overlay capability has grown in importance with the combination of increasing pattern density and new techniques such as double patterning and immersion lithography.

Contact:

John Allgair, ISMI Metrology Program Manager
john.allgair@ismi.sematech.org

Brad Theil, SEMATECH Metrology Program Director
brad.thiel@sematech.org