Advances in engineering nanometrology at the National Physical Laboratory

Abstract

The National Physical Laboratory, UK, has been active in the field of engineering nanometrology for a number of years. A summary of progress over the last five years is presented in this paper and the following research projects discussed in detail. (1) Development of an infrastructure for the calibration of instruments for measuring areal surface topography, along with the development of areal software measurement standards. This work comprises the use of the optical transfer function and a technique for the simultaneous measurement of topography and the phase change on reflection, allowing composite materials to be measured. (2) Development of a vibrating micro-CMM probe with isotropic probing reaction and the ability to operate in a non-contact mode. (3) A review of x-ray computed tomography and its use in dimensional metrology. (4) The further development of a metrology infrastructure for atomic force microscopy and the development of an instrument for the measurement of the effect of the probe–surface interaction. (5) Traceable measurement of displacement using optical and x-ray interferometry to picometre accuracy. (6) Development of an infrastructure for low-force metrology, including the development of appropriate transfer artefacts.

Mechanical design and optimization of a suspension of multi-function sensing probes

“…1 (f) presents a threefold-symmetric assembly based on the design by F.G. Balzer. [11]; (b) assembly of the Gannen-XP design [12]; (c) assembly of the NPL design [13]; (d) cross-shaped beam assembly by X. Liu [2]; (e) assembly of the design by F.G. Balzer [10]; (f) the proposed threefold-symmetric beam assembly.…”

The Differential Method for Force Measurement Based on Electrostatic Force

“…The small force measurement is very important with development of the technology [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. It involves precision instrument, MEMS [1,2], biology [12,13], magnetic field distributions [14,15], and tribological properties of material [16][17][18][19].…”

“…This setup could measure forces less than 10-5 N, whose resolution is 10-12 N [5,6]. The National Physical Laboratory (NPL) developed a force balance with working range from 10 −9 N to 10 −6 N [7,8]. The Korean Research Institute of Standards and Science (KRISS) built a nanoforce calibrator that realized the calibration of cantilevers whose stiffness ranges within 0.01∼100 N/m, with a relative standard uncertainty of 1% [9,10].…”

Correlation and convolution filtering and image processing for pitch evaluation of 2D micro- and nano-scale gratings and lattices

“…Microscopes and instruments include a family of scanning probe microscopes (SPM) [1], scanning electron microscopes (SEM) [2,3], various optical microscopes and contact stylus instruments that are used for areal surface roughness measurement [4,5]. Usually, metrological atomic force microscopes (AFM) and nano-measuring machines (NMM) [6][7][8] implement the metrological verification. This typically includes two steps: acquiring the three-coordinate topographic signal in raster-scan mode, and afterwards evaluating the pitch-related parameters according to a pitch evaluation method.…”