NiO thin films by MOCVD of Ni(dmamb)(2) and their resistance switching phenomena

Abstract

We have synthesized the volatile, liquid, nickel precursor Ni(dmamb)(2), nickel bis(1-dimethylamino-2-methyl-2-butanolate), Ni[OC(CH3) (C2H5)CH2N(CH3)(2)](2), and employed it in the MOCVD of nickel oxide (NiO). A stainless steel, cold-wall, low-pressure reactor was employed to grow the NiO films on Si and Pt/SiO2/Si substrates. In addition, the resistance switching property of the Pt/NiO/Pt capacitor structure was investigated. The substrate temperature was varied in the range 230-410 degrees C. The films deposited were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and I-V measurements. They were polycrystalline showing dominantly the NiO (I 11) peak in their X-ray diffraction patterns. The films were found to be almost stoichiometric with the Ni:O ratio of 1.1:0.9 and no appreciable amount of carbon incorporation was detected by XPS. The I-V measurements revealed an interesting switching property of the NiO films showing low and high resistance states thereby suggesting their application as ReRAM devices. (c) 2007 Elsevier B.V. All rights reserved.