Ultrahigh-precision multilayer film thickness drift error calibration method

Abstract

The invention relates to an ultrahigh-precision multilayer film thickness drift error calibration method, which comprises the steps of of alternately moving a substrate to a sputtering region of two target materials for plating a multilayer film, and plating a first periodic multilayer film; enabling the substrate to be far away from the sputtering region, continuing sputtering the target materials, and simulating the plating process of the target periodic multilayer film; alternately moving the substrate plated with the first periodic multilayer film to the sputtering region again, and plating a second periodic multilayer film to form a calibration sample; and performing an X-ray grazing incidence reflection test on the plated calibration sample under fixed X-ray energy to obtain a test reflectivity curve, and obtaining a multilayer film drift error from the beginning to the end based on comparison between the test reflectivity curve and the simulated reflectivity curve, wherein the number of film pairs of the first periodic multilayer film and the second periodic multilayer film is 1 / 10-1 / 5 of the number of film pairs of the target periodic multilayer film. Compared with the prior art, the method has the advantages of high precision, small influence of instrument conditions and the like.

Description

technical field [0001] The invention belongs to the technical field of optical thin films, and in particular relates to an ultra-high-precision multilayer film thickness drift error calibration method, in particular to the calibration of high-precision film thickness errors of large-film logarithmic X-ray multilayer films. Background technique [0002] The one-dimensional nanometer (nm) multilayer film structure is an important reflection element in the X-ray band, which can realize the reflection and monochromatization of X-rays outside the total external reflection region. A conventional multilayer film is composed of an absorbing layer with a high atomic number and a spacer layer with a low atomic number, and the reflection bandwidth (ΔE / E) is about 2% to 5%. With the development of applications such as synchrotron radiation light source devices, the requirements for the monochromatization performance of multilayer films are getting higher and higher, and high-resolution ...

AI Technical Summary

Problems solved by technology

But even if the transmission electron microscope is used, although its ideal spatial resolution can reach 0.1nm, when the actual film grows, there will be atomic diffusion and mixing on the interface and surface, so it is difficult to accurately determine the boundary of film thickness calculation, and the calibration accuracy is far from reaching its resolution, and it is impossible to measure the thickness error of tens of picometers

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