Multi-channel scanning measuring system for testing of diffractive structures and thin transparent films

The development of specialized non-destructive methods for monitoring of microstructured optical elements is necessary for introduction of diffractive, micro-optical and conformal optical elements into production. However, a wide variety of such elements, as well as their production technologies, set many tasks in the implementation of process control both at the final and at the intermediate stages of the formation of a multilevel and binary phase element. All this requires the use of various expensive equipment, each of which individually does not allow solving the whole range of tasks. Multichannel scanning measuring system that implementing spectroscopic and diffraction testing methods was developed at IA&E SB RAS. The device includes four measuring channels allowing to measure the following parameters and characteristics: transmission function of half-tone masks in zeroth order or as sum of all diffraction orders; thickness of transparent films covered on substrate (by the spectroscopic method in reflection); measurement of the zero-order intensity of diffraction structures, both in transmission and in reflection in range of wavelengths from 200 nm to 1100 nm; measurement of the diffraction efficiency of the first and zero orders of diffraction in reflected light (including for structures made in optically transparent materials) for monitoring the parameters of the formed relief of multilevel elements.