Heat-Resistant Black Insulative Thin Films for Flat-Panel Displays in Al-Doped Ag–Fe–O Systems

Abstract

Multilayer antireflection (AR) coatings require a material with a large and constant absorption coefficient over the whole visible range and thermal stability. Coatings for use in touch panel displays are also required to be electrically insulative. In this study, 60 mol % Ag–40 mol % (Fe1–x Al x )–O (x = 0, 0.25, 0.50, 0.75, and 1.0) thin films are prepared by pulsed laser deposition, and their optical properties, electric resistance, and thermal stability are clarified by combining the experimental data and density functional theory (DFT) calculations. Over the visible range, large and constant absorption coefficients are obtained for all compositions. The standard deviations of the absorption coefficients of the x = 0.75 and 1.0 samples are found to be smaller than those of conventional materials like graphite and CrO x . High sheet resistance (R sheet > 107 Ω·sq–1) is also confirmed. It is determined that nanometer-sized Ag dispersed into a matrix, which was confirmed to be ionic Ag in the matrix phase, is responsible for the absorption at a shorter visible light range and insulative nature even at high Ag content. The films with high Al content are stable up to 500 °C. The potential of these black insulative Ag–Al–Fe–O thin films for use as black AR coatings is confirmed by optical simulations with multilayer stacks.

Key Role of Interfacial Cobalt Segregation in Stable Low-Resistance Composite Oxygen-Reducing Electrodes

“…PLD processing is also beneficial for revealing the synergistic effects because PLDderived composites have a well-defined and large interfacial area on the nanoscale. 32,48 The findings of this study provide new insights into the synergistic effects, which are expected to be valuable for developing SOFC oxygen electrodes and could be applied to other applications that include gas−solid reactions.…”