Influence of Annealing on the Dielectric Properties of Zn-SiO₂/Si Nanocomposites Obtained in "Hot" Implantation Conditions

This paper presents the results of AC electrical measurements of Zn-SiO2/Si nanocomposites obtained by ion implantation. Implantation of Zn ions was carried out into thermally oxidized p-type silicon substrates with energy of 150 keV and fluence of 7.5 x 10(16) ion center dot cm(-2) at a temperature of 773 K, and is thus called implantation in "hot" conditions. The samples were annealed in ambient air for 60 min at 973 K. Electrical measurements of Zn-SiO2/Si nanocomposites were carried out before and after annealing. Measurements were performed in the temperature range from 20 K to 375 K. The measurement parameters were the resistance R-p, the capacitance C-p, the phase shift angle theta and the tangent of loss angle tan delta, as a function of the frequency in the range from 50 Hz to 5 MHz. Based on the characteristics sigma(f) and the Jonscher power law before and after sample annealing, the values of the exponent s were calculated depending on the measurement temperature. Based on this, the conductivity models were matched. Additionally, the real and imaginary parts of the dielectric permittivity were determined, and on their basis, the polarization mechanisms in the tested material were also determined.