Excellent cross-talk isolation, high-Q inductors, and reduced self-heating in a TFSOI technology for system-on-a-chip applications

In this paper, novel structures are reported to improve the cross-talk isolation, the performance of on-chip inductors, and the self-heating in a thin-film silicon-on-insulator (TFSOI) technology. In these structures, p⁺ substrate contact rings are used to improve the cross-talk isolation, appropriately doped TFSOI layers are used for high-Q inductors, and source contacts connected to the substrate are used to minimize the self-heating problem. The p⁺ substrate contact rings provide -57 dB isolation (typically characterized for a device spacing of 100 μm) at 10 GHz, which is the best ever reported in TFSOI technology. A maximum Q-factor of 10.4 is obtained for TFSOI-layer shielded on-chip inductors. The inductor-to-inductor isolation is -62 dB (for a spacing of 100 μm) at 10 GHz, which is close to the ideal isolation of the open probes. The source contacts connected to the substrate improves the self-heating by 16%. The excellent cross-talk isolation performance, high-Q on-chip inductors, and reduced self-heating make the TFSOI technology a very suitable candidate for mixed signal system-on-a-chip (SOC) applications