Extraction of trap location and energy from random telegraph noise in amorphous TiOx resistance random access memories

Random telegraph noise (RTN) has been studied in amorphous TiOx (alpha-TiOx) resistance switching random access memories (RRAMs). The RTN having two discrete current levels was observed only in the high-resistance state of the RRAMs. By investigating the bias dependence of capture and emission time constants, we extracted the vertical location of a trap responsible for the RTN in RRAM devices. The trap causing the RTN was found around 5.7 nm below the Ti (top electrode). The trap energy was less by 0.18 eV than the conduction band edge of the TiOx. (C) 2011 American Institute of Physics. [doi:10.1063/1.3575572]