DOI: 10.18503/1995-2732-2023-21-3-137-143
Abstract
Problem Statement (Relevance). The development of modern technology and microelectronics fosters the improvement of methods applied to produce and process thin-film superconducting micro- and nanostructures, including YBa2Cu3O7-x (YBCO) films. This determines the relevance of the task of forming superconducting YBCO films on strontium titanate substrates with a thickness of over 50 nm. Methods Applied. To form thin-film microstructures, the authors used a multifunctional universal laser lithography unit with an Nd:YAG solid-state laser with radiation wavelengths of 532 and 1064 nm. Originality. The authors have first detected threshold power densities, when the film starts melting and photoablation occurs. It has been revealed that at a laser radiation wavelength of λ = 532 nm, the threshold of laser ablation for YBCO films with a thickness of 30 to 200 nm is reached at an energy density of 1.36 J/cm2. Regarding YBCO films with a thickness of 100 nm, the laser ablation threshold is 1.44 J/cm2 at λ =1064 nm of laser exposure. It has been established that in case of infrared laser radiation, thin-film coatings with a thickness of less than 40 nm become transparent, presenting an obstacle to creating a film-based microstructure. Result. We have determined the optimal values of the laser radiation energy density to form the qualitative YBCO film photoablation boundary, and threshold values of the laser radiation energy density that correspond to film melting. Practical Relevance. The detected threshold value of energy density, when a qualitative boundary of the YBCO films photoablation is formed at a laser wavelength of 532 nm, turned out to be 1.36 J/cm2. This indicates that the YBCO thin films have a sufficiently high absorption coefficient of such radiation; therefore, this radiation can be used to form microstructures in the wide thickness range.
Keywords
superconducting structures, laser exposure, energy density, YBCO films, laser lithography
For citation
Pozygun I.S., Seropyan G.M., Sychev S.A., Fedosov D.V., Teploukhov A.A., Semenyuk N.A. Features of Interaction between Nanosecond Laser Radiation and YBCO Films. Vestnik Magnitogorskogo Gosudarstvennogo Tekhnicheskogo Universiteta im. G.I. Nosova [Vestnik of Nosov Magnitogorsk State Technical University]. 2023, vol. 21, no. 3, pp. 137-143. https://doi.org/10.18503/1995-2732-2023-21-3-137-143
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