Design of Miniature Bandpass Filters Embedded in the Organic Substrate for RF SOP Applications

Abstract

Very small-size bandpass filters embedded in the organic substrate for RF System-On-Package (SOP) applications are presented. Due to the lack of fabrication process for largevalue capacitors in the organic substrate, a novel filter prototype using an inductive coupling of series resonators is proposed to achieve high performance within a stringent size constraint. In implementation, the organic bandpass filters are composed of the spiral inductors and parallel-plate capacitors that are embedded in a 4-layer BT laminate, one of today's most popular package substrate. The final realized performance and size are competitive to the LTCC filters but with a much lower cost.Index Terms -Organic filter, band-pass filter, RF system on package.

Design and fabrication of bandpass filters in glass interposer with through-package-vias (TPV)

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Development of miniature LTCC filter for TV broadcasting band by using substrates of mixed dielectrics

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