A Passive Low-Pass Filter on Low-Loss Substrate
低损耗衬底上实现无源低通滤波器

The loss mechanisms of different passive devices (on-chip inductors and capacitors) on different substrates are analyzed and compared.OPS (oxidized porous silicon) and HR (high-resistivity) substrates are used as low-loss substrates for on-chip planar LPF (low pass filter) fabrication.For the study of substrate loss,a planar coil inductor is also designed.Simulation results show that Q (the quality factor) of the inductor on both substrates is over 20.Measurements of the LPF on OPS substrate give a -3dB bandwidth of 2.9GHz and a midband insertion loss of 0.87dB at 500MHz.The LPF on HR substrate gives a -3dB bandwidth of 2.3GHz and a midband insertion loss of 0.42dB at 500MHz.