Theoretical study of photonic bands of one-dimensional photonic crystals containing epsilon-near-zero metamaterials.

The photonic bands of a one-dimensional photonic crystal containing epsilon-near-zero metamaterials are investigated both theoretically and numerically. A theoretical expression of the edge frequencies of the photonic bands derived from the dispersion relation of the photonic crystal is in excellent agreement with the edge frequencies of the photonic bands calculated using the plane wave expansion method. These results are also confirmed using the transmittance obtained from the transfer matrix method.

Stabilization of gamma alumina slurry for chemical-mechanical polishing of copper.

Stabilization of gamma-alumina suspension for chemical-mechanical polishing (CMP) of copper was investigated. Citric acid and poly(acrylic acid) (PAA) (M(w)=5000) were used as dispersant. The stability of suspension was evaluated from the changes in viscosity, particle size and zeta potential.