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We created a test object of the linewidth with three different certified sizes. Relief structures of the test object are individual steps and protrusions, as well as pitch structures with trapezoidal profile, created by anisotropic etching of monosilicon. The orientation of the silicon surface coincides with the (1 0 0) crystallographic plane. The structures are located in two orthogonal directions. We present the results of the study of the individual relief elements (protrusions and steps) with the help of a scanning electron microscope (SEM) and an atomic-force microscope (AFM). The widths of the upper bases of the protrusions are in the 14-400 nm range. We performed a correlation analysis of the experimental results, which demonstrates the high quality of the created structures.

Results of investigations in the field of measurements of geometrical characteristics of the electron beam of a scanning electron microscope (SEM) are presented. Methods for determining the electron beam diameter are developed and tested on various microscopes. Besides, methods for obtaining the dependence of the electron beam diameter on the beam current, the energy of the primary electrons, and the focusing of the beam are also developed. Finally, method for determining the electron density distribution in the electron beam is proposed.

At the IX Session of the Commission of Length in September 1997, the values of the frequency and wavelength of He–Ne laser emission, stabilized by a saturated absorption line in molecular iodine, ν = 473 612 214 705 kHz, λ = 632.991 398 22 nm, were recommended. The emission of such lasers is used all over the world as a material bearer of a length unit. In Russia, reproduction and transmission of its size is realized with the help of a reference interferometric device, an atomic force microscope of original design, where displacement along the X, Y and Z axes is controlled by a laser interferometric nanodisplacement measuring device. By this means, scanning in all three coordinates is measured in fractions of laser emission wavelength, which in its turn serves as a material unit length bearer. In practice, linear measurements in the nanometre range are carried out with scanning electron (SEM) and scanning probe (SPM) microscopes. A standard of the width of the line and of the pitch, called ‘MShPS-2.0K’, is used in Russia. This standard enables us to determine the SEM magnification, as well as the effective diameter of its electron probe. Moreover, one can determine the SPM scale factor for the three scanning axes, the Z-scanner nonorthogonality and the effective radius of the SPM cantilever tip by means of the standard MShPS-2.0K (Russian abbreviation). The authors describe in the present paper the methods for the linear measurements in the nanometre range with the use of the SEM and SPM. These methods were proposed by Russian specialists, and have been employed at Russian research institutes as well as at Russian manufacturing enterprises.

Comparison is made for parameters and properties of test objects based on the relief structures with right-angled and trapezoidal profiles, which are used for calibration of scanning electron microscopes (SEMs) and atomic force microscopes (AFMs). Methods of calibration of SEMs and AFMs with help of this test objects are presented. Comparative analysis has shown that trapezoidal structures with large angles of sidewall inclination, created by anisotropic etching of silicon with the (100) orientation of its surface, possess the most universal characteristics. Such structures could be used for development of internationally recognized measures of length in the nanometer range for calibration of SEMs and AFMs.