Ultralow Dielectric Properties of <TEX>$SiO_2$</TEX> Aerogel Thin Films

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J. Korean Ceram. Soc. > Volume 34(3); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(3): 314.

실리카 에어로겔 박막의 극저 유전특성

현상훈, 김중정, 김동준, 조문호, 박형호

연세대학교 세라믹공학과

Ultralow Dielectric Properties of $SiO_2$ Aerogel Thin Films

ABSTRACT

The thin film processing and the applicability as a IMD material of SiO2 aerogels providing ultralow dielec-tric properties were studied. The SiO2 aerogel films with 0.5g/㎤ density (78% porosity) and 4000~21000$AA$ thickness could be prepared at 25$0^{circ}C$ and 1160 psig by supercritical drying of wet-gel films, which were spin-coated at the spin rate of 1000~7000 rpm on p-Si(111) wafer under the isopropanol atmosphere. The optimum viscosity of polymeric SiO2 sols for spin coating was in the range of 10~14 cP. The main fac-tors being able to control the film thickness and microstructures were found to be sol concentration, spin rpm, and aging time of wet-gel films. The dielectric constant of the SiO2 aerogel thin film was around 2.0 low enough to be applied to the next generation semiconductor device beyond the giga level.

Key words: $SiO_2$ aerogel thin film, Ultralow dielectrics, Intermetal dielectric material, Spin coating, Supercritical drying