CaCu3Ti4O12: Future Material for Fabricating Small-Size Capacitors

Abstract

In recent years, giant dielectric materials have been playing a significant role in microelectronic devices such as capacitors and memory devices. This is because such devices often require materials with high dielectric constants (') and low loss tangents (tanδ). CaCu₃Ti₄O₁₂ has gained considerable interest both scientifically and technologically. Its giant dielectric constant exhibits values in the range of 10³-10⁵ at room temperature, depending on ceramic microstructures and processing conditions. It is now widely accepted that the origin of the giant dielectric response in the CaCu₃Ti₄O₁₂ ceramics is attributed to the Maxwell-Wagner
polarization effect at grain boundaries. Unfortunately, their tanδ values are still too large. Investigation to optimize the value tanδ by controlling the microstructure and doping metal ions into CCTO ceramics is therefore important.