Molecular dynamics based on the environment-dependent interatomic potential is used to investigate the influence of the nature and distribution of defects on solid state, homogeneous amorphization of Si. To this end, different kinds of defects, including single interstitials and vacancies (both uncorrelated and correlated distributions), bond defects, and small interstitial and vacancy clusters, have been considered. It is shown that the threshold defect concentration for amorphization depends on the defect type, and, in the case of single defects, on the degree of correlation between interstitial and vacancy distributions. The threshold varies within the interval [0.18-0.28] atomic fraction, the upper value corresponding to the case of bond defects, the lower to the uncorrelated distributions of single 110 split interstitials plus compensating vacancies.

Pyroelectric thick films of 0.92PbZrO3–0.03PbTiO3–0.05Pb(Zn1/3Nb2/3)O3 were prepared by a screen printing method on ceramic substrates using platinum bottom electrodes. A phase transition between two rhombohedral ferroelectric phases was observed for the poled thick film through the measurement of the temperature dependence of pyroelectric coefficient. The effects of the firing temperature and the types of ceramic substrates were examined. These pyroelectric thick films are very promising for use in the fabrication of highly sensitive infrared array detectors.

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