In our study, the physical properties of (TiO 2) x (SiO 2) 1-x, including band-gap, band-offset, and thermal stability and the electrical properties of band-engineered SiO 2/(TiO 2) x (SiO 2) 1-x tunnel barrier stacks, including the tunneling current and charge-trapping characteristics for applications to nonvolatile memory devices were investigated. It was observed that the band-gap and band-offset of (TiO 2) x (SiO 2) 1-x can be controlled by adjustment in the composition of the (TiO 2) x (SiO 2) 1-x films. Ti-silicate film with TiO 2: SiO 2 cycle ratio of 1:5 was maintained in an amorphous phase, even after annealing at 950°C. The tunneling current of the band-engineered SiO 2/(TiO 2) x (SiO 2) 1-x stacked tunnel barrier was larger than that of a single SiO 2 barrier under a higher external bias, while the tunneling current of a SiO 2/(TiO 2) x (SiO 2) 1-x stacked tunnel barrier under a lower external bias was smaller. Charge-trapping tests showed that the voltage shift for SiO 2/(TiO 2) x (SiO 2) 1-x is slightly larger than that for single SiO 2.
|Number of pages||6|
|Journal||Applied Physics A: Materials Science and Processing|
|Publication status||Published - 2012 Sep|
All Science Journal Classification (ASJC) codes
- Materials Science(all)