N-Type Porous Silicon Substrates for Integrated RF Inductors

To study the effect of various n-type substrates on high-frequency inductor performances, several devices were integrated on porous silicon (PS), silicon (Si), and glass. Both n-type mesoporous Si and mesoporous/macroporous Si bilayers were fabricated. The analysis further shows that PS reduces significantly the substrate losses. Indeed, higher quality factors have been obtained for the inductors integrated on PS than on the Si substrate and particularly in the case of bilayer structures. These original results can be added to p-type PS performances already shown in the literature. Then, this work demonstrates that PS can also be a promising candidate for the integration of passive and active devices on n-type silicon.