By Topic

Liquid–Metal Vertical Interconnects for Flip Chip Assembly of GaAs C-Band Power Amplifiers Onto Micro-Rectangular Coaxial Transmission Lines

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
Ralston, P. ; Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA ; Oliver, M. ; Vummidi, K. ; Raman, S.

Prior work has demonstrated a new process utilizing room-temperature liquid metal, Galinstan, as an interconnect material for flip-chip bonding. This interconnect forms a flexible bond between chips and carriers, and, therefore, a flip-chip assembly using this technology is much less susceptible to thermomechanical stresses. This paper applies this concept to interconnect GaAs MMIC chips to 3-D Polystrata transmission-line structures. Passive assemblies are utilized to model, test, and verify liquid-metal interconnections, giving average losses per liquid-metal transition of about 0.11 dB out to 26.5 GHz, low parasitics per transition, and demonstrated reliability after temperature cycling. A prefabricated GaAs MMIC chip is postprocessed for liquid-metal assembly. Measured results show, over the MMIC's 4.9-8.5-GHz frequency range, the system's overall reduction in gain of the MMIC is 1.4 dB or 0.7 dB per RF transition as compared with direct probing of the MMIC chip.

Published in:

Solid-State Circuits, IEEE Journal of  (Volume:47 ,  Issue: 10 )