Enhanced resistive switching and multilevel behavior in bilayered HfAlO/HfAlO{sub x} structures for non-volatile memory applications
- Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal)
In this work, hafnium aluminum oxide (HfAlO) thin films were deposited by ion beam sputtering deposition technique on Si substrate. The presence of oxygen vacancies in the HfAlO{sub x} layer deposited in oxygen deficient environment is evidenced from the photoluminescence spectra. Furthermore, HfAlO(oxygen rich)/HfAlO{sub x}(oxygen poor) bilayer structures exhibit multilevel resistive switching (RS), and the switching ratio becomes more prominent with increasing the HfAlO layer thickness. The bilayer structure with HfAlO/HfAlO{sub x} thickness of 30/40 nm displays the enhanced multilevel resistive switching characteristics, where the high resistance state/intermediate resistance state (IRS) and IRS/low resistance state resistance ratios are ≈10{sup 2} and ≈5 × 10{sup 5}, respectively. The switching mechanisms in the bilayer structures were investigated by the temperature dependence of the three resistance states. This study revealed that the multilevel RS is attributed to the coupling of ionic conduction and the metallic conduction, being the first associated to the formation and rupture of conductive filaments related to oxygen vacancies and the second with the formation of a metallic filament. Moreover, the bilayer structures exhibit good endurance and stability in time.
- OSTI ID:
- 22486236
- Journal Information:
- Applied Physics Letters, Vol. 107, Issue 24; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Intrinsic SiO{sub x}-based unipolar resistive switching memory. II. Thermal effects on charge transport and characterization of multilevel programing
Unipolar resistive switching behavior of amorphous YCrO{sub 3} films for nonvolatile memory applications