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

This paper presents the integration of WLAN (2.4 and 5 GHz) bandpass filters in glass interposer using through-package vias. The filters include novel embedded passive components such as stitched capacitors with reduced shunt parasitics and via-based inductors that provide area reduction. The filters designed for 2.4 GHz showed an insertion loss of less than 2 dB and better than 15 dB return loss, while the 5 GHz filters showed an insertion loss of less than 1 dB with better than 20 dB return loss. Stop-band rejection of over 35 dB was observed at 2.2 GHz on the 2.4 GHz bandpass filters. The measured results showed good agreement with the simulated values and indicated that the performance on glass interposer closely matches the performance of the more expensive high resistivity silicon with similar properties.