A metal-insulator-semiconductor (MIS) structure containing a HfO2control gate, a Ge nanocrystal-embedded HfO2dielectric and a HfO2/SiO2stack layer as tunnel oxide, was fabricated by an electron-beam evaporation method. High-resolution transmission electron microscopy study revealed that the HfO2/SiO2stack layer minimized Ge penetration, leading to the formation of Ge nanocrystals that are self-aligned between the tunnel oxide and the capping HfO2layer. Influence of different annealing conditions on the formation and distribution of Ge nanocrystals was studied. Current-voltage (I-V) and capacitance-voltage (C-V) measurements revealed promising electrical characteristics of the MIS structure, and relatively high stored charge density of 1012cm-2was achieved.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)