Papers by Author: Adam Łaszcz

Abstract: Transmission electron microscopy (TEM) techniques were used for characterization of annealing (400, 600 and 800 °C) influence on the structural properties of the HfO₂ film (45 nm thick) deposited on Si substrate. Such structures are considered as high-k dielectric materials for application in novel semiconductor devices. The studies showed that independently of the annealing temperature a very thin and flat amorphous layer is formed between HfO₂ layer and Si substrate. This result was also found in the non-annealed sample. EDXS examination confirmed that the stoichiometry for the hafnium oxide layer in each sample corresponds to 1:2 for Hf:O (i.e. to HfO₂). TEM images revealed differences in the microstructure of HfO₂ layers in annealed samples, however the layers have similar thickness and interface roughness in all studied samples.

Abstract: We present results of the study on the silicon nanoparticles formation in multilayer silicon nitride structures. These structures consist of pairs of stoichiometric silicon nitride dielectric layers (SiN_x) and silicon rich nitride layers (SRN). Silicon nanocrystals precipitate from the SRN layer during annealing at high temperatures (1000 °C or 1100 °C). High resolution transmission electron microscopy has been applied for investigation of the nanocrystals formation. Surface photovoltage spectroscopy technique was used for the spectral characterization of prepared structures