TEM and XPS studies of nanocrystals and clusters in nanostructured materials used for memory storage applications

Abstract

Nanoscaled electronic devices have attracted much attention due to their optical and electronic properties, especially related to MOS (Metal-Oxide-Semiconductor) devices used for memory storage applications. Improved electrical properties, longer retention, lower gate voltage and lower power consumption are assumed to be possible when replacing bulk floating gate in flash memory devices with nanocrystals. Multilayer samples with Si, Ge, Er-oxide, and Pd nanocrystals and clusters were studied in detail. The nucleation, distribution, defects, composition, and atomic and electronic structure are important factors to understand in order to improve performance of memory storage devices. These parameters were studied by high resolution transmission electron microscopy, energy filtered transmission electron microscopy, electron energy loss spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and secondary ion-mass spectrometry.