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|
Bibliographical noteFunding Information:
This work was financially supported by the IT R&D program of MKE/KEIT (development of novel 3D stacked devices and core materials for the next generation flash memory) and the second stage of the Brain Korea 21 project (BK21).
All Science Journal Classification (ASJC) codes
- Materials Science(all)