Authors: J-H Yoon
Affilation: Kangwon National University, Korea
Pages: 429 - 432
Keywords: Cobalt, nanocrystal, nonvolatile memory
In this study, we report the direct growth of cobalt (Co) silicide nanocrystals (NCs) by thermally annealing of a simple sandwich structure consisting of an ultrathin Co layer sandwiched between two silicon-rich oxide (SiOx) layers, which are grown by plasma-enhanced chemical vapor deposition (PECVD) using fixed flow rates of SiH4 and N2O. Ultrathin Co layer were deposited using a conventional thermal evaporation method. Nucleation and growth of Co-based NCs were achieved by thermal annealing the sandwich structures at elevated temperature in a quartz-tube furnace using high purity nitrogen gas as an ambient. The method demonstrates that the Co silicide NCs grow into well-defined boundaries and approximately spherical shape within the SiO2 matrix. Capacitance-voltage (C-V) measurements on a test structure, which was formed with the following layers: tunnel SiO2/SiO1.53/Co film(0.2 nm)/SiO1.53/control SiO2 are shown to have C-V characteristics suitable for nonvolatile memory applications, including a C-V memory window of about 10 eV.