Porous silicon as a substrate for the integration of high performance on-chip antennas

Abstract

In this paper we report on the application of low-loss and low-permittivity thick porous Si (PSi) layer as a local substrate on bulk Si wafer for the on-chip integration of millimeter wave antennas (∼50 GHz). The necessary PSi area, thickness and dielectric permittivity for optimized performance of the dipole antenna are investigated through 3D simulations. The simulated antenna is fabricated on a locally formed 150 μm thick PSi layer and compared to an identical antenna on bulk low resistivity Si (1–10 Ω.cm). It was found that the gain of the antenna on PSi was improved from −24 dBi on bulk Si to −13 dBi on the PSi layer. Good agreement between measurements and simulations was observed.