Metrological Precision Research Articles

Precision metrology of micro-workpieces on their tribological performance with an error compensation method

A test system with a new compensation method is introduced to precisely evaluate the tribological performance of the micro-machining of workpieces under a load of mill-Newton scale. Since the tribological force is faint in micro-scale, the tested result is influenced significantly by the testing error. The new metrology method to precisely evaluate the friction coefficient of micro-bearings is developed by means of error compensation from two sets of testing data. The data are, respectively, collected when the friction counterparts rotate clockwise and counter-clockwise. Because the friction coefficient is deduced from the measuring force data, this method enhances the metrological precision of the friction coefficient theoretically due to the counteracting of the error values in the equation.

3D micro-inspection goes DMD

Digital image-projection and video-projection are the classical applications of Digital Micromirror Devices (DMD) but further applications in the field of optical metrology are also possible. Operated with certain patterns, a DMD can function, for instance, as an array of pinholes that may substitute the Nipkow disk presently used for lateral scanning in confocal microscopes. The various process parameters that influence the measurement (e.g. pinhole size, pinhole shape, lateral step-size and the number of pinholes used simultaneously, etc.) can be configured easily for individual measurements by simply programming the DMD. Furthermore, price-drops for metrological precision instruments may be achieved by implementation of the mass article DMD. The paper explains the basics of DMD technology, illustrates the principle setup of a newly designed instrument, shows results achieved with it and gives examples for its application.

Compare, Standardize and Settle Agreement

Historical and sociological studies have shown that precision measurement and metrology play an important social and scientific role. This paper contrasts the dynamics of four metrological configurations. The first concerns an instrument for routine car repair. It displays the network of institutions, conventions and procedures allowing for the conservation of legal metrological precision. Such resources are not yet available during the genesis of an instrument. Very often in scientific laboratories, instruments and their metrology are elaborated simultaneously. The three other case studies analyze this construction by looking at ordinary metrological operations: the collective elaboration of standards; the translation of scientific instruments in metrological laboratories; and the intercomparison of instruments. It appears that the diversity and heterogeneity of resources associated with metrological networks result in different ways of articulating the natural and conventional character of precision measurement.

Methods for mask defect detection using local criteria

Local pattern properties specified by general design rules can be used for detection of defects on photolitographic masks. The advantage is, that no comparison between adjacent chip images or an external data base is required. So the need for high metrological precision becomes unnecessary. Local deviation from straightness or admissible contour angles can be used as detection criterias. Different algorithms were tested on simulated images containing various defect types. The simplicity of the logical operators used permits implementation as circuitry fast enough to process a video data rate up to 10 MHz in real time.

Detection of defects on the surface of microelectronic structures

Many types of defects on photolithographic masks can be detected by using only local pattern properties specified by general design rules. No comparison between adjacent chip images or an external data base is required, eliminating the need for high metrological precision. A number of detection criteria such as local deviations from straightness or admissible contour angles were tested on simulated images containing various defect types. Usable algorithms that could be implemented as high-speed circuits permitting data throughputs at TV rates are discussed. >

Metrological servicing and precision in batch production of balances

Metrological servicing and precision in batch production of balances