Millimeter-Wave Transmission Line in 90-nm CMOS Technology

A twice interleaved metal patterns is proposed for decreasing transmission line loss and maintaining operating bandwidth when using 90-nm complementary metal-oxide-semiconductor technology. Three transmission lines are implemented in this experiment. The measurement results show that the location of interleaved metal patterns in metal-1 and metal-2 films decreases the attenuation constant and increases the operating bandwidth compared to the conventional transmission line. To deeply understand the phenomenon, the effective height is calculated to analyze the experiment result. The comparison results show the proposed and conventional transmission lines obtain attenuation constants of 0.26 dB/mm and 0.71 dB/mm at 40 GHz . The proposed transmission line can potentially make huge improvements in millimeter-wave operation.