Abstract

The phase velocities in coplanar transmission lines on Si-on-sapphire (SOS) substrates had been studied by Frankel et al.¹ In their work, the sapphire layer was 430-μm thick. In ICs, however, the interconnections are buried in thin SiO₂ layers with typical thicknesses of 1 to 2 μm. Therefore, the delay of these lines are quite different from those on SOS substrates. In this work, we have studied the phase velocities of coplanar strip (CPS) transmission lines on Si/SiO₂/Si multilayer substrates. Because the top Si layer of the substrate is very thin, the phase velocity measured in our experiments should be close to that in ICs.

© 1996 Optical Society of America