Simple and low‐loss flip‐chip bonding based on ink‐jet printing for RF applications

Abstract

In this Letter, a flip-chip bonding based on ink-jet printing technology is proposed and verified by interconnecting a separated coplanar waveguide (CPW) samples. Before the flip-chip bonding process, diameter and height of ink-jet printed silver bumps for flip-chip bonding are measured to be about 300 and 13 µm, respectively. In a frequency range from 300 kHz to 3 GHz, return loss and insertion loss of the flip-chip bonded CPW samples are measured to be higher than 20 dB and lower than 1.8 dB, respectively, where the length of the signal line is 35 mm. There are negligible discrepancies between radio frequency (RF) characteristics of the flip-chip bonded CPW and those of a conventional CPW. These results show that the proposed flip-chip bonding can be used to integrate RF components into electronic devices with low-loss using simple procedures.

Wavelet transform-based characterization of printing ink penetration depth and image phase dissimilarity

“…Literature [12] explores the future of inkjet printing and explores a novel fabrication technique for inkjet printed sensors to reduce the cost of printers. Literature [13] proposes and validates a trigger based on inkjet printing technology in order to simplify the printing technique. Literature [14] investigated the effect of different blistering agents and printing parameters on the depth of penetration of printing ink and found experimentally that the increase in ink thickness decreases the depth of penetration and peel strength of the blister varnish while the amount of thinner also affects the depth of penetration of the blister varnish.…”