arXiv subjects

M. N. Drozdov

Publications and source records attributed to M. N. Drozdov.

3 recordsLinked to original sources

arXiv2024

Magneto-optical Control of Ordering Kinetics and Vacancy Behavior in Fe-Al Thin Films Quenched by Laser

One of issues arising in materials science is a behavior of non-equilibrium point defects in the atomic lattice, which defines the rates of chemical reactions and relaxation processes as well as affects the physical properties of solids. It is previously theoretically predicted that melting and rapid solidification of metals and alloys provides a vacancy concentration in the quenched material, which can be comparable to that quantity at the point of melting. Here, the vacancy behavior is studied exerimentally in thin films of the near equiatomic Fe-Al alloy subjected to nanosecond laser annealing with intensities up to film ablation. The effects of laser irradiation are studied by monitoring magneto-optically the ordering kinetics in the alloy at the very ablation edge, within a narrow (micron-scale) ring-shaped region around the ablation zone. Quantitatively, the vacancy supersaturation in the quenched alloy has been estimated by fitting a simulated temporal evolution of the long-range chemical order to the obtained experimental data. Laser quenching (LQ) of alloys and single-element materials would be a tool for obtaining novel phase states within a small volume of the crystal.

cond-mat.mtrl-sci↗

arXiv2018

99.992 % $^{28}$Si CVD-grown epilayer on 300 mm substrates for large scale integration of silicon spin qubits

Silicon-based quantum bits with electron spins in quantum dots or nuclear spins on dopants are serious contenders in the race for quantum computation. Added to process integration maturity, the lack of nuclear spins in the most abundant $^{28}$silicon isotope host crystal for qubits is a major asset for this silicon quantum technology. We have grown $^{28}$silicon epitaxial layers (epilayers) with an isotopic purity greater than 99.992 % on 300mm natural abundance silicon crystals. The quality of the mono-crystalline isotopically purified epilayer conforms to the same drastic quality requirements as the natural epilayers used in our pre-industrial CMOS facility. The isotopically purified substrates are now ready for the fabrication of silicon qubits using a state-of-the-art 300 mm Si CMOS-foundries equipment and processes

cond-mat.mtrl-sci↗

arXiv2017

Quantitative depth profiling of Si1-xGex structures by time-of-flight secondary ion mass spectrometry and secondary neutral mass spectrometry

Quantification of Ge in Si1-xGex structures (0.092 0.9997) of intensity ratios of GeCs2+/SiCs2+ and 74Ge-/30Si- secondary ions and post-ionized 70Ge+/28Si+ sputtered neutrals with Ge concentration was obtained. The calibration data were used for quantitative depth profiling of [10x(12.3 nm Si0.63Ge0.37/34 nm Si)] structures on Si. Satisfactory compliance of the quantified Ge concentration in SiGe layers with the data measured by high-resolution X-ray diffraction was obtained for both techniques. Both SIMS and SNMS experimental profiles were fitted using the Hofmann mixing-roughness-information depth (MRI) model. In case of TOF-SIMS the quality of the reconstruction was higher than for SNMS since not only the progressing roughening, but also crater effect and other processes unaccounted in the MRI simulation could have significant impact on plasma sputter depth profiling.

cond-mat.mtrl-sci↗