GET 203-2024 state primary special standard of complex refractive index and length in the field of measuring the thickness of optical coatings

A large number of fields in science and technology, such as optics, microelectronics, optoelectronics, and integrated optics, deal with measuring the optical and geometric properties of thin films. The need to ensure measurement uniformity in these fields led to the creation of GET 203-2012 State primary standard of complex refractive index. With the use of GET 203-2012, the complex refractive index was measured using the method of spectral ellipsometry through the measurement of ellipsometric angles. However, GET 203-2012 did not support the thickness measurement of coatings when measuring their complex refractive index. In 2020–2023, VNIIOFI improved GET 203-2012, expanding its functional capabilities to reproduce the unit of length in the field of measuring optical coating thickness. The improved standard was approved as GET 203-2024 State primary special standard of complex refractive index and length in the field of measuring the thickness of optical coatings. GET 203-2024 ensures uniformity in measuring the complex refractive index and the unit of length in optical thickness measurement within the range of 1 nm to 50 μm. The extended range was realized with the use of an IR ellipsometer equipped with an FTIR (Fourier transform infrared) spectrometer. Extending this range is relevant for such fields as optics, microelectronics, optoelectronics, integrated optics, and other areas of science and technology. The composition, operating principle, and main metrological characteristics of GET 203-2024 are presented.