Materials Chemistry and Physics, Vol.156, 76-81, 2015
Orientational growth and resistive switching behavior of anatase TiO2 thin films
Crystalline anatase TiO2 films were produced via a hydrothermal route from an aqueous solution containing ammonium hexafluorotitanate [(NH4)(2)TiF6, Al-IFT] at 95 degrees C. During the hydrothermal growth, seed layer was introduced, and F-scavenger was avoided. As-grown TiO2 films have fine structure comprising closely stacked and well-arranged TiO2 crystal whiskers with a preferred orientation in [001] direction and the diameter size about 20-30 nm. The resistance switching (RS) device made of the hydrothermal TiO2 film shows the bipolar resistive switching behavior (BRS) with a resistance ratio about 10, low switching voltage, and good retainance stability. The shortened channels for oxygen vacancies due to the oriented structure are ascribed to the good RS behavior. Further growth experiments demonstrate that the seed layer and the high F- concentration are crucial for film density and orientation. Patterned TiO2 film can be grown using this hydrothermal route, which shows potential application in resistive switching random access memory (RRAMs) devices. (C) 2015 Elsevier B.V. All rights reserved.