Total Ionizing Dose Response of Triple-Well FET-Based Wideband, High-Isolation RF Switches in a 130 nm SiGe BiCMOS Technology

The effects of 63 MeV proton irradiation on the RF performance (insertion loss, isolation, and linearity) of triple-well nFET-based RF switches designed in a 130 nm SiGe BiCMOS technology are investigated. The switches were designed for wide-band operation (1 to 40 GHz) and were required by the application to achieve high isolation (> 35 dB at 40 GHz) with moderate insertion loss (dB at 40 GHz). The RF switch IL improves (S₂₁ increases) at 100 and 500 krad(SiO₂), but degrades (S₂₁ decreases) at 2 Mrad(SiO₂). P1dB and IIP3 (switch linearity) shows a similar TID response, at 100 and 500 krad(SiO₂) dose an increase of ~ 0.4 dBm and ~0.2 dBm, respectively. However, at 2 Mrad(SiO₂) both sharply decrease. Standalone RF and dc structures were also irradiated to better understand the underlying mechanisms affecting the switch RF performance. The bias dependence of the radiation-induced change on the measured RF performance of a SPST switch is also analyzed. 10 keV X-ray radiation experiments were conducted on separate dc transistor structures to provide additional insight into the measured impact of total ionization dose on the performance of RF switches.