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J Huennekens, A Allegrini, Zeina J. Kubarych, R Sagle, R K. Namiotka
Populations of excited atoms that all have the same z component of velocity can be produced by pumping a vapor with a narrow-band laser. This velocity-selected population is then thermalized by velocity-changing collisions. However, in a pure vapor, even
A new NIST SEM magnification calibration standard has been fabricated and characterized in production prototype form. The SRM 2090A samples contain structures ranging in pitch from 3000 um to 0.2 um and are useful at both high and low accelerating voltages
Lateral dopant profiling of cleaved, passivated abrupt GaAs pn junctions using scanning tunneling microscopy/spectroscopy is demonstrated both in ultrahigh vacuum and air. A combination of forward-and reverse-bias imaging and position-dependent tunneling
A novel design for an ultraviolet critical dimension measurement transmission microscope utilizing the Stewart platform as the rigid main structure has been implemented. This new design shows improved vibration characteristics and is able to accommodate
Richard M. Silver, James E. Potzick, Robert D. Larrabee
The relative misalignment of features produced by different mask levels (i.e., overlay error) is projected to become an increasingly important problem to the semiconductor industry as the size of the critical features continues to decrease. In response to
J Schneir, T Mcwaid, Ronald G. Dixson, V W. Tsai, John S. Villarrubia, Edwin R. Williams, E Fu
NIST personnel visited 23 IC manufacturing companies and equipment suppliers during 1994 to determine semiconductor industry needs for scanned probe metrology. NIST has initiated projects addressing some of the needs identified. When complete, these
Every artifact measurement standard has some uncertainty associated with its calibration, and the NIST Photomask Linewidth Standards are no exception. This uncertainty is caused by a combination of those factors which influence the calibration measurement
Sinusoidal surfaces can be used as material standards to help calibrate instruments that measure the angular distribution of the intensity of light scattered by arbitrary surfaces, because the power in the diffraction peaks varies over several orders of
In a phase measuring interferometer (PMI), the interference pattern is focused on a charge coupled device (CCD) detector array and data points are sampled at the corresponding locations. In most commercially available systems, a zoom lens forms part of the
Amy Singer, J Land, Steven D. Phillips, Daniel S. Sawyer, Bruce R. Borchardt, Gregory W. Caskey, D Ward, P Snoots, B Faust
The Interim Testing Artifact (ITA) is designed to quickly test CMMs for performance problems so that they can be repaired before significant numbers of good parts are erroneously rejected (or bad parts accepted) by the CMM. Frequent testing using the ITA
Jun-Feng Song, F Rudder, Theodore V. Vorburger, A Hartman, Brian R. Scace, J Smith
Microform calibrations include the measurement of complex profile forms and position errors of micrometer scale in combination with the measurement of deviations from a specified profile and surface texture of profile segments. Tolerances on the profile
Steven D. Phillips, Bruce R. Borchardt, William T. Estler
This paper examines the measurement uncertainty of small circular features as a function of the sampling strategy, i.e., the number and distribution of measurement points. Specifically, we examine measuring a circular feature using a three-point sampling
Current Rockwell C hardness scales (HRC) are unified by performance comparisons. Unless a reliable metrology approach is used for the direct verification of standard hardness machines and diamond indenters, the unified hardness scale may exhibit a
The aim of the project is to investigate the potential of expanding the instrument measurement bandwidth of a traditional phase measurement interferometer (PMI) system using a comparatively simple optical / software modification. This would offer the
The continuing drive within high technology industries to push dimensional tolerances to still smaller values motivates the use of surface measuring techniques with better resolution. This requirement can be met by the scanning probe microscopy (SPM)
A microform calibration procedure has been developed at NIST to certify geometric conformity of Rockwell C hardness indenters. The interest in microform calibrations is to unify national and international comparisons of hardness tests. Using accepted
A computer model and methodology for modeling optical mixing errors in heterodyne interferometers is presented. The model is based on the Jones calculus and uses a matrix formalism to eliminate simplifications and reduce assumptions in the model. The model
Studies have been carried out to determine the influence of different chemical environments and tool shapes on damage produced during diamond tool scratching and indenting of two advanced ceramics: chemical-vapor-deposited silicon carbide and a composite
As increasing number of economically important products manufactured by U.S. companies are comprised of assemblies of macroscopic parts with microscopic tolerances, that is, parts from a few to hundreds of millimeters in size where the acceptable
J Smith, Jun-Feng Song, F Rudder, Theodore V. Vorburger
Based on the Rockwell diamond indenter's microform calibrations recently developed at NIST, as well as a deadweight standardized Rockwell hardness machine, the NIST Rockwell hardness standard calibration has been established. Our approach makes it possible
Nitin P. Padture, Christopher J. Evans, Hockin D. Xu, Brian R. Lawn
The machinability of a heterogeneous silicon carbide with weak interphase boundaries, elongated grains, and high internal stresses is evaluated relative to a homogeneous control material with a well-bonded, equiaxed, and unstressed grain structure