DuPont? Green Tape? 9K7 Low Temperature Co-fired Ceramic (LTCC) Low Loss Dielectric System for High Frequency Applications

摘要

The DuPont? Green Tape? 9K7 Low Temperature Co-fired Ceramic (LTCC) system is a majorrntechnological advancement for use in high frequency applications in consumer, telecommunications, automotive andrnmilitary electronic devices. The system provides low electrical resistance at high frequencies; compatibility withrnlow-cost silver conductors; feasibility for miniaturization; the ease to incorporate buried resistors & capacitors; andrnlong term reliability. In this work, the new low loss dielectric LTCC systems consisting of tapes, gold and silverrnconductors, resistors, and capacitors are examined to evaluate the effects of chemistry, processing conditions,rnprocessing latitude, microstructure and dielectric properties.rnThe 9K7 tape chemistry is based on a proprietary, partially crystallizable high refractory glass and ceramicrnfillers which form a fired “glass ceramic-ceramic-glass” LTCC composite structure. The high frequency propertiesrninclude a dielectric constant of ～ 7.1 and dielectric loss of 0.0010 at ～ 9.5 GHz with little or no variation as arnfunction of refires. Also demonstrated is the stability of the system and its long term reliability in terms of thernfunctional properties such as wire bonding, soldered adhesion, surface smoothness and bulk microstructures.