A kind of preparation method of far ultraviolet high reflection mirror

Abstract

The invention relates to a preparation method of a far ultraviolet high reflectivity mirror. The preparation method comprises the following steps of cleaning, film coating, annealing and storing and comprises the following specific steps that during film coating, high vacuumizing is carried out, then a base plate which is cleaned thoroughly is etched by using ion beams, a bottom layer Cr film is plated firstly, then an Al film is plated in a heat evaporation mode, when the temperature is increased to 180-220 DEG C, a film coating chamber is baked, vacuumizing is continuously carried out, an Al2O3 film on the surface of the Al film is etched by using argon ion beam flow, and then an MgF2 thin film is obtained through electron beam evaporation; and vacuumizing is carried out, annealing is carried out for 3 hours at the temperature of 250-300 DEG C so as to improve the quality of a sample thin film, and the sample is filled with N2 and then is placed into a drying cabinet for storage. Compared with the prior art, the far ultraviolet high reflectivity film prepared by using the method is excellent in optical property, high in reflectivity, good in environmental stability and capable ofbeing prepared in batches, and a wide application prospect in the field of future optical thin films is achieved.

Description

technical field [0001] The invention relates to the field of far-ultraviolet optical film preparation, in particular to a preparation method of a far-ultraviolet high reflection mirror. Background technique [0002] The far ultraviolet high reflective mirror is widely used in many research fields that use measurement in the far ultraviolet spectral region of the 100-200nm band, and has very important research significance. For example, high-resolution spectroscopic measurements from rockets, satellites, and stars, astronomical observations in the ultraviolet band, construction and application of synchrotron radiation beamlines, etc., high reflectors are one of the important optical components. [0003] Improving the reflectivity of the far-ultraviolet high reflection mirror is extremely important for the research of the far-ultraviolet band, but the materials suitable for the far-ultraviolet are limited. The Al film has high reflectivity in the far ultraviolet band and has ...

AI Technical Summary

Problems solved by technology

[0003] Improving the reflectivity of the far ultraviolet high reflector is extremely important for the research of the far ultraviolet band, but the materials suitable for the far ultraviolet are limited

The Al film has high reflectivity in the far ultraviolet band and has good adhesion to the glass substrate, so Al is the first material used as a high reflective thin film element in the far ultraviolet band. The disadvantage is that the surface of the Al film is easily oxidized to form Al 2 o 3 film, while Al 2 o 3 The film has a strong ability to absorb radiation below 160nm, which makes the reflectivity of the Al film drop sharply.

According to the survey, even if the same film system is used, the reflectance is not exactly the same, and some even have a large difference.

In order to prepare high-quality reflectors suitable for far-ultraviolet wavelengths, it is necessary to further study the production of Al films by thermal evaporation and the deposition of MgF by electron beam evaporation. 2 Film parameters such as vacuum degree, deposition rate, coating purity, coating temperature, etc., storage environment, time stability and other factors affect its performance. At present, there is no suitable Al+MgF 2 Preparation method of far ultraviolet high reflective mirror

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