Colloidal Synthesis of Cobalt Nanoparticles for Application in Non Volatile Memory Device

Abstract

Paper describes a simple and cost effective process for non volatile memory (NVM) device. This method involves colloidal synthesis of cobalt nanoparticles for their application in spin coating based NVM device. Cobalt possesses appropriate work function and large number of density of states which are favorable features for their application in NVM device. Further, availability of number of easy methods for colloidal synthesis of cobalt nanoparticles provide an opportunity to use such colloidal synthesized nanoparticles for spin coating based NVM device. The spin coating of colloidal cobalt nanoparticles, being a key process step to the fabrication of NVM device, is studied using atomic force microscopy and energy dispersive X-ray characterizations methods. The metal-oxide-semiconductor (MOS) NVM capacitor has been fabricated using 600 rpm for 30 s spin coating condition. The capacitance-voltage $(C-V)$ response of the device show a high memory window of $7.5 \mathrm{V}$ for applied sweep voltage of $\pm 8 \mathrm{V}$ , useful for the achieving big memory window in actual NVM device. Also, the capacitance-time (C-t) response indicates excellent retention of the fabricated device.