Broadband complementary metal-oxide semiconductor single-pole-double-throw switch with improved power handling capability using dual-gate metal-oxide semiconductor field-effect transistors

A broadband complementary metal-oxide semiconductor (CMOS) single-pole-double-throw (SPDT) switch based on a travelling-wave design with using dual-gate N-type metal-oxide semiconductor (NMOS) transistors is implemented in a 0.18 μm CMOS process for millimetre-wave applications. To further investigate the power handling capability in a dual-gate metal-oxide semiconductor field-effect transistor (MOSFET), this study analyses the mechanism of voltage swing distribution by using the proposed large-signal cascode model. Considering the parasitic gate-to-gate capacitance and the substrate effect, the simulations in this study can accurately predict the small-signal and power handling performances of the SPDT switch. The switch exhibits a measured 1 dB bandwidth of ~51 GHz, ranging from 16 to 67 GHz with an insertion loss of 3.6 dB at 30 GHz. The measured isolation is also better than 22 dB. The measured power handling capability can achieve a 1 dB compression point at an input power of 23.8 dBm at 30 GHz with a negative body bias, and the simulation result shows a 1 dB compression point nearly 24 dBm. Based on the proposed model, the large-signal performances under different body biases can be significantly predicted when including the parasitic gate-to-gate capacitance in a dual-gate MOSFET.