Structural and noise characterization of VO2 films on SiO2/Si substrates

Multi-technique structural and electrophysical investigations of VO2 films on SiO2/Si substrates are carried out to study the microscopic nature of fluctuator defects — sources of lowfrequency flicker noise. It is established that the noise intensity is determined by the magnitude of the microstress fluctuations 〈ε 〉={〈(δc/c)2〉}, where c is the lattice parameter along the c-axis parallel to [011] direction in the blocks of which the film is formed. The dimensions of the blocks were determined in the direction of the c-axis (tc∼1000 Å). The suggestion is put forward that the samples contain two types of fluctuator defects: 1) V atoms jumping between the two nearest interstitial sites and 2) V atoms jumping between these interstitial sites near lattice defects.