Traceable Calibration of a Critical Dimension Atomic Force Microscope
Ronald G. Dixson, Ndubuisi G. Orji, Craig D. McGray, Jon C. Geist
The National Institute of Standards and Technology (NIST) has a multifaceted program in atomic force microscope (AFM) dimensional metrology. One component of this effort is a custom in-house metrology AFM, called the calibrated AFM (C-AFM). The NIST C-AFM has displacement metrology for all three axes traceable to the 633 nm wavelength of the iodine-stabilized He-Ne laser. A second major component of this program is the use of critical dimension atomic force microscopy (CD-AFM). CD-AFM is a commercially available AFM technology that uses flared tips and two-dimensional surface sensing to scan the sidewalls of near-vertical features. Features of this sort that are commonly encountered in semiconductor manufacturing and other nanotechnology industries. NIST has experience in the calibration and characterization of CD-AFM instruments and in the development of uncertainty budgets for typical measurands in semiconductor manufacturing metrology. A third generation CD-AFM was recently installed at NIST. The current performance of this instrument for pitch and height measurements appears to support our relative expanded uncertainty goals in the range of 1.0 10-3 down to 1.0 10-4.
Proceedings of SPIE, Vol. 8036
April 26-28, 2011
Scanning Microscopies 2011: Advanced Microscopy Technologies for Defense, Homeland Security, Forensic, Life, Environmental, and Industrial Sciences