MOD法によりSi₃N₄/SiO₂メンブレン上に製作したVO_xマイクロボロメータの特性評価

抄録

VO_x thin films were fabricated on Si₃N₄/SiO₂/Si substrates by firing precursor films, which were fabricated by metal-organic decomposition (MOD), with a reduced pressure. Resistance-temperature (R-T) characteristics of the films indicating the phase transition from metal to insulator with about 4 orders of resistance change specified with VO₂(M) were obtained. Furthermore, the films fabricated with a firing temperature of 580 ∼ 600 ºC had temperature coefficient of resistance (TCR) of -2.8 ∼ -2.9 %/K at room temperature. After fabricating VO_x microbolometers with 40×10 µm² using the films on Si₃N₄/SiO₂/Si substrates, Si with a thickness of about 340 µm was etched using Deep-RIE and XeF₂ vapor etching from the backside of the substrate. Then, the VO_x microbolometer was completed on Si₃N₄/SiO₂ membrane. The VO_x microbolometer on Si₃N₄/SiO₂ membrane had a high DC sensitivity of 2310 W^-1, which was about 15 times higher than that of the microbolometer on the Si₃N₄/SiO₂/Si substrate.