Thermodynamic Analysis of Stoichiometric Composition Changes in the Ti_xO_y Films at RF Magnetron Sputtering and Modeling of Their Conductivity

Abstract

Herein, the results of experiments on the synthesis of nonstoichiometric titanium oxide films by magnetron sputtering at various partial oxygen pressures and discharge powers are presented. The thermodynamic analysis of the synthesis results is performed by minimizing the Gibbs free energy of the equilibrium thermodynamic system, which takes place in the chamber. The dependences of the concentration of the main components in the deposition chamber on the partial pressure of oxygen and the discharge power, including the concentration of synthesized titanium monoxide and dioxide, are obtained. The analysis of these dependences allows determining the conditions for the critical values of the partial pressures of oxygen at which the oxides are synthesized. The exponential dependence of the conductivity on oxygen pressure is found experimentally and explained on the basis of hopping conductivity over the states of defects on the surface of nanocrystals that form the synthesized films.

Diagnosis of the technology of titanium and hafnium oxides by luminescence methods

“…This may be due to the fact that the defects are concentrated in the surface layer of nanocrystals, which form a film immediately after synthesis. An increase in the partial pressure of oxygen increases the number of crystallization centers, as a result, nanocrystals become smaller, and their number increases, which is confirmed by the data of X-ray phase analysis [17]. Therefore, their combined surface becomes larger, and the concentration of defects as a whole increases.…”

Диагностика Технологии Оксидов Титана И Гафния Методами Люминесценции

“…Это может быть связано с тем, что дефекты сосредоточены в поверхностном слое нанокристаллов, которые образуют пленку сразу после синтеза. Рост парциального давления кислорода увеличивает число центров кристаллизации, в результате нанокристаллы становятся более мелкими, и количество их растет, что подтверждается данными рентгеновского фазового анализа [17]. Поэтому совокупная их поверхность становится больше, и концентрация дефектов в целом растет.…”