Memory characteristics of metal-oxide-semiconductor capacitor with high density cobalt nanodots floating gate and HfO_2 blocking dielectric

摘要

In this letter, cobalt nanodots (Co-NDs) had been formed via a self-assembled nanodot deposition. High resolution transmission electron microscopy and x-ray photoelectron spectroscopy analyses clearly show that the high metallic Co-ND is crystallized with small size of ～2 nm and high density of (4-5) × 10~(12)/cm~2. The metal-oxide-semiconductor device with high density Co-NDs floating gate and high-k HfO_2 blocking dielectric exhibits a wide range memory window (0-12 V) due to the charge trapping into and distrapping from Co-NDs. After 10 years retention, a large memory window of ～1.3 V with a low charge loss of ～47% was extrapolated. The relative longer data retention demonstrates the advantage of Co-NDs for nonvolatile memory application.