Using of ion-beam etching of free-standing films for the development of wavefront correctors in the EUV wavelength range

A method for creating free-standing film elements designed to correct wavefront aberrations in optical systems in the spectral region of the soft X-ray and extreme ultraviolet range has been proposed. Samples of film structures with a uniform transmission across the aperture of at least 60% at a wavelength of 13.5 nm, serving as the initial basis for the formation of phase correctors with a characteristic value of phase modulation corresponding to a change in the optical path length of $\sim$1 nm, were manufactured. The possibility of using ion etching to locally change the thickness of free-standing multilayer films has been demonstrated.