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The purposes of this paper are to investigate the post deposition annealing (PDA) effect on structural and electrical characterizations of HfO 2 MOS capacitor and the frequency dependency of series resistance and interface states in this device. PDA processes on the HfO 2 films deposited using RF magnetron sputtering system were performed in N 2 ambient at 350, 550, 650, and 750°C. The phase identifications and crystallization degrees of the HfO 2 films were determined by using X-ray diffractometry. The grain size of the films was varied from 4.5 to 15.23 with increasing in PDA temperature. The HfO 2 MOS capacitors were fabricated using the as-deposited and annealed films for electrical characterization. C-V and G/ x-V measurements were performed at 1 MHz frequency. The C-V characteristics of the MOS capacitor fabricated with film annealed at 550°C show a better behaviour in terms of the high dielectric constant and low effective oxide charge compared to others. For this device, C-V and G/x-V measurements were performed in different frequencies ranging from 10 kHz to 1 MHz at room temperature. Obtained results show that series resistance and interface states strongly influence the C-V and G/x-V behaviour of the MOS capacitor.

In the presented work, the parameters of a new MAPD-3NM-II photodiode with buried pixel structure manufactured in cooperation with Zecotek Company are investigated. The photon detection efficiency, gain, capacitance and gamma-ray detection performance of photodiodes are studied. The SPECTRIG MAPD is used to measure the parameters of the MAPD-3NM-II and scintillation detector based on it. The obtained results show that the newly developed MAPD-3NM-II photodiode outperforms its counterparts in most parameters and it can be successfully applied in space application, medicine, high-energy physics and security.

We report on the use of direct laser interference patterning to form an "anisotropy" lattice in Co/ Pt thin film multilayers. Co/ Pt multilayers have been extensively studied and, for the compositions studied here, are characterized by strong perpendicular magnetic anisotropy in which the magnetic moment is perpendicular to the film plane. In direct laser interference patterning, two-to-four coherent laser beams from a pulsed Nd:YAG laser strike the sample surface simultaneously, and for sufficiently intense beams the sample properties are modified locally where interference maxima occur. Kerr rotation, magnetic force microscopy, and atomic force microscopy measurements after patterning by one pulse from the laser show that the films have a regular array of "dots" with in-plane magnetization in a background matrix of perpendicular magnetization. Such patterning holds promise for the study of model nanoscale magnetic systems.

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