Non-stoichiometric AlOx Films Prepared by Chemical Vapor Deposition Using Dimethylaluminum Isopropoxide as Single Precursor and Their Non-volatile Memory Characteristics

Dimethylaluminum isopropoxide (DMAI, (CH3)(2)(AlOPr)-Pr-i) as a single precursor, which contains one aluminum and one oxygen atom, has been adopted to deposit non-stoichiometric aluminum oxide (AlOx) films by low pressure metal organic chemical vapor deposition without an additional oxygen source. The atomic concentration of Al and O in the deposited AlOx film was measured to be Al:O = similar to 1:1.1 and any serious interfacial oxide layer between the film and Si substrate was not observed. Gaseous by-products monitored by quadruple mass spectrometry show that beta-hydrogen elimination mechanism is mainly contributed to the AlOx CVD process of DMAI precursor. The current-voltage characteristics of the AlOx film in Au/AlOx/Ir metal-insulator-metal (MIM) capacitor structure show high ON/OFF ratio larger than similar to 10(6) with SET and RESET voltages of 2.7 and 0.8 V, respectively. Impedance spectra indicate that the switching and memory phenomena are based on the bulk-based origins, presumably the formation and rupture of filaments.