Insertion loss characteristics of passive devices fabricated on anodized aluminum oxide layers formed on Si substrates

We report on the high-frequency insertion loss behaviors of a passive device patterned on a new type of insulating layer that consists of nanoporous anodized aluminum oxide (AAO) on a Si substrate. The transmission line loss and characteristics of simple capacitors were characterized by a series of RF measurements. The insertion loss of the transmission line on the hybrid insulating layer consisting of AAO and silicon dioxide (SiO₂) was smaller than that on the SiO₂ single insulating layer. This hybrid insulating layer approach appears to be promising for the development of integrated passive devices that require an insertion loss of the order of -0.621 dB up to 20 GHz. A simple MIM capacitor manufactured on the hybrid insulating layer operated very well in the RF range.