Through-silicon via technologies for interconnects in RF MEMS

Various holes in through-silicon via (TSV) technologies are analyzed and realized by inductively coupled plasma (ICP) process. Using TSV technologies as grounding connections, a Ku band miniature bandpass filter is designed and fabricated. Measured results show an insertion loss of 1.9 dB and a bandwidth of 20%. The chip size is 9.6 mm times mm. Using it as interconnections for 3-dimentional millimeter-wave integrated circuits, a silicon micromachined vertical transition with three layers is presented. TSV, alignment, bonding and wafer thinning technologies are used to fabricate the sample. After measurement it exhibits an insertion loss of less than 3.5 dB from 26.5 GHz to 34 GHz and an amplitude variation of less than 2 dB. The total size of the chip is 6.3 mm times 3.2 mm.