Resistance noise at the metal–insulator transition in thermochromic VO2 films

Abstract

Articles you may be interested inRadio frequency substrate biasing effects on the insulator-metal transition behavior of reactively sputtered VO2 films on sapphire (001) Influence of doping with alkaline earth metals on the optical properties of thermochromic VO2 Mg doping of thermochromic VO 2 films enhances the optical transmittance and decreases the metal-insulator transition temperature Appl. Phys. Lett. 95, 171909 (2009); 10.1063/1.3229949 Thermal dynamics of VO 2 films within the metal-insulator transition: Evidence for chaos near percolation threshold Appl.Thermochromic VO 2 films were prepared by reactive DC magnetron sputtering onto heated sapphire substrates and were used to make 100-nm-thick samples that were 10 lm wide and 100 lm long. The resistance of these samples changed by a factor $2000 in the 50 < T s < 70 C range of temperature T s around the "critical" temperature T c between a low-temperature semiconducting phase and a high-temperature metallic-like phase of VO 2 . Power density spectra S(f) were extracted for resistance noise around T c and demonstrated unambiguous 1/f behavior. Data on S(10 Hz)/R s 2 scaled as R s x , where R s is sample resistance; the noise exponent x was À2.6 for T s < T c and þ2.6 for T s > T c . These exponents can be reconciled with the Pennetta-Tref an-Reggiani theory [Pennetta et al., Phys. Rev. Lett. 85, 5238 (2000)] for lattice percolation with switching disorder ensuing from random defect generation and healing in steady state. Our work hence highlights the dynamic features of the percolating semiconducting and metallic-like regions around T c in thermochromic VO 2 films. V C 2015 AIP Publishing LLC. [http://dx.

Thickness dependent transition from the 1T′ to Weyl semimetal phase in ultrathin MoTe2: electrical transport, noise and Raman studies

“…The noise scaling close to MIT transition is S I /I 2 ∝ R x , where x is the universal exponent [34]. For MIT, x ∼ 2.6 [34]. In comparison, in our case x ∼ 100 which is shown by the dotted line in Fig.…”

“…2(d), we re-plot the Noise amplitude versus resistance (R) to examine the expected scaling seen earlier near MIT [34]. The noise scaling close to MIT transition is S I /I 2 ∝ R x , where x is the universal exponent [34]. For MIT, x ∼ 2.6 [34].…”

Electrical Switching in Thin Film Structures Based on Transition Metal Oxides

“…Further simulation of computing with networks of synchronous oscillators based on MIT-devices has been recently presented in [150]. Note that thermally induced oscillations [151,152], resistance noise [153], negative capacitance [154], and some other possible concomitant phenomena should apparently be taken into account when constructing neuromorphic circuits on the basis of switching devices with a MIT-induced NDR.…”

Phase‐selective Route to V‐O Film Formation: A Systematic MOCVD Study Into the Effects of Deposition Temperature on Structure and Morphology

“…Several techniques have been used to prepare films of vanadium oxides, such as pulsed laser deposition, molecular beam epitaxy, and magnetron sputtering . Atomic layer deposition (ALD) has also been applied, but even given the benefits of high control of the layer thickness and also high uniformity, excellent step coverage, and high reproducibility, the low deposition rate may represent a drawback for large‐scale applications.…”