Enhanced RF Switch Performance in RFSOI Technology: Achieving 74 fs R_ON·C_OFF and 3.3 V RFV_MAX on Thinned SOI

As 6G connectivity demands to improve up-to-date CMOS Silicon-on-Insulator (SOI) RF Front End Modules (FEMs) performances, lower Ron C Coff values are required for the next generation of switches, while maintaining equal or higher breakdown voltages. In this paper, we demonstrate that reducing SOI thickness is an effective approach for pushing further the capabilities of modern RF switch devices, diminishing parasitic capacitance $C_{\text {OFF }}$ without affecting devices’ power handling. With respect to our technology reference, $R_{O N} \cdot C_{\text {OFF }}$ has been reduced by 14%, achieving Ron $\cdot C_{\text {OFf }} / R F V_{\text {Max }}$ state-of-art values of $74 \mathrm{fs} / 3.3 \mathrm{~V}$. Furthermore, RF breakdown is studied, revealing that the dominant reason that limits power handling in OFF-state conditions is leakage current, ascribed to Gate-Induced Drain Leakage (GIDL), parasitic bipolar triggering, and punch through. In addition, a non-destructive method to estimate $R F V_{\text {Max }}$ value by means of DC measurements is proposed, providing a rapid and reliable in-process-line method for power handling characterization of RF switch devices.