MEASUREMENT 2011, Proceedings of the 8th International Conference, Smolenice, Slovakia 95 Dimensional Micro- and Nanometrology at PTB R. Köning, J. Flügge, D. Hüser, W. Haessler-Grohne, H.U. Danzebrink, G. Dai, U. Brand, V. Nesterov, S. Bütefisch, G. Ehret, M. Wurm, B. Bodermann, E. Buhr, H. Bosse Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100,38116 Braunschweig, Email: rainer.koening@ptb.de Abstract. In this contribution we will provide an overview of the current state and the actually ongoing developments in the field of dimensional micro- and nanometrology at PTB. That is, we will report on the methods and instruments developed, applied and that are in development for high precision, traceable measurements in these important areas of dimensional metrology. Keywords: Dimensional Metrology, Nanometrology, Micrometrology, Traceability 1. Introduction The control of the geometrical dimensions in the industrial production of single components and whole systems demands appropriate measurement techniques. The related measurement instruments have to be chosen according to different criteria like throughput, robustness, price, 3D-capability, in-line ability, measurement range, required resolution and accuracy. Meanwhile, dimensional features in the area of micro- and microsystem technology can be characterized and controlled during production on the basis of traceable measurement results in the same way as in conventional manufacturing process control. In nanotechnology the desired properties of the product often depend much stronger on the geometrical dimensions or even appear as a consequence of the reduced dimensions and therefore even tighter specifications have to be met. Here the progress made in the available measurement equipment over the last two decades has just enabled this field of technology. Dimensional metrology instruments aiming at the smallest measurement uncertainties achievable have to comply with two fundamental requirements. Firstly a well-designed and well-characterized positioning system, which provides a relative movement of the measurement object with its functional dimensional features of interest with respect to the probing system of the measurement instrument, is mandatory. Secondly, a sound physical model of the interaction of the probing system with the dimensional features of the sample should be available and applied in the evaluation of the measurement results. This is particularly important if the size of the features comes close to the resolution limit of the probing system. The measurement of some geometrical properties, for example the diameter of nanoparticles, is simply impossible without considering the probe sample interaction. We will show examples of different probing methods in this paper, namely tactile, opto- tactile, optical and electron beam methods and discuss challenges for future developments in micro- and nanometrology. 2. Micrometrology In micrometrology the dimensions of measurement objects are usually in the range of some 100 m to some mm. Typically the required measurement uncertainties of the dimensional features are in the range of 0.1 µm or below. Several metrology institutes developed, built and meanwhile operate suitable reference measurement systems for dimensional characterization