Sintering Effects on Structure, Morphology, and Electrical Properties of Sol-Gel Synthesized, Nano-Crystalline Erbium Oxide

The nano-crystalline erbium oxide powder was synthesized through the sol-gel technique. The effect of sintering temperature from 250 degrees C to 1400 degrees C on structure, morphology, and electrical properties was studied. The results were compared with the microcrystalline erbium oxide purchased from the market. The synthesized erbium oxide showed fiber like nanostructures. Dielectric properties at different sintering temperatures were measured in the frequency range 100 Hz to 5 MHz. The synthesized erbium oxide had the highest dielectric constant at 650 degrees C. The behavior of the dissipation factor tan delta for sol-gel synthesized material was distinct from that of the purchased material; it was higher at low frequencies and then decreased with the increase in frequency. The synthesized material sintered at different temperatures exhibited a similar sort of frequency-dependent response for permittivity (is an element of) and resistivity (rho). This was in accordance with Koop's theory of dielectrics. For the microcrystalline material, frequency dependence of permittivity and resistivity was not uniform. The results showed that sol-gel synthesized erbium oxide could be a good candidate for high-k applications.