Resonance-free millimeter-wave coplanar waveguide Si microelectromechanical system package using a lightly-doped silicon chip carrier

A silicon (Si) microelectromechanical system (MEMS) package using a lightly-doped Si chip carrier for coplanar waveguide (CPW) microwave and millimeter-wave integrated circuits (MMICs) is proposed in order to reduce parasitic problems of leakage, coupling, and resonance. The proposed chip carrier scheme is verified by fabricating and measuring a GaAs CPW on two types of carriers (conductor-back metal and lightly-doped Si) in the frequency range 0.5 to 40 GHz. The proposed MEMS package using the lightly-doped (15 Ω·cm) Si chip carrier and the high resistivity silicon (HRS, 15 kΩ·cm) shows the low loss and resonance-free since the lightly-doped Si chip carrier effectively absorbs and suppresses the resonant leakage. The Si MEMS package for CPW MMICs has an insertion loss (S ₂₁) of 2.0dB, a reflection loss (S₁₁) of 10dB, and a power loss (PL) of 7.5 dB at 40 GHz.