TY - JOUR
T1 - Processing and electrical characterization of a varistor-capacitor cofired multilayer device
AU - Toal, Francis J.
AU - Dougherty, Joseph P.
AU - Randall, Clive A.
PY - 1998/9
Y1 - 1998/9
N2 - A comprehensive study of the materials selection, processing, cofiring, and electrical characterization of a multilayer varistor/capacitor (MLVC) device has been presented. The goal was to achieve component miniaturization and provide superior high-frequency and high-amplitude transient-voltage protection. A ZnO-based material and 0.75Pb-(Mg1/3Nb2/3)O3-0.25Pb(Zn 2/3Nb2/3)O3 (PMN-PZN) were chosen as the respective varistor and capacitor components. Using a controlled-profile furnace, PMN-PZN with excess PbO resulted in an optimum cofiring with a complex varistor composition. The sintering study made it clear that the ability to cofire is dependent not only on matching sintering temperatures and final densities but also sintering rates. Composite-pellet studies assured the mechanical and electrical integrity of the device and indicated that interaction between the respective components was minimal. Prototype MLVC devices were fabricated using standard tape-casting techniques. Microstructural analysis of the MLVCs revealed solid ceramic/ceramic and ceramic/electrode interfaces with little evidence of interaction. Current-voltage and dielectric measurements both indicated good electrical properties that can be specifically tailored by changing the layer thickness.
AB - A comprehensive study of the materials selection, processing, cofiring, and electrical characterization of a multilayer varistor/capacitor (MLVC) device has been presented. The goal was to achieve component miniaturization and provide superior high-frequency and high-amplitude transient-voltage protection. A ZnO-based material and 0.75Pb-(Mg1/3Nb2/3)O3-0.25Pb(Zn 2/3Nb2/3)O3 (PMN-PZN) were chosen as the respective varistor and capacitor components. Using a controlled-profile furnace, PMN-PZN with excess PbO resulted in an optimum cofiring with a complex varistor composition. The sintering study made it clear that the ability to cofire is dependent not only on matching sintering temperatures and final densities but also sintering rates. Composite-pellet studies assured the mechanical and electrical integrity of the device and indicated that interaction between the respective components was minimal. Prototype MLVC devices were fabricated using standard tape-casting techniques. Microstructural analysis of the MLVCs revealed solid ceramic/ceramic and ceramic/electrode interfaces with little evidence of interaction. Current-voltage and dielectric measurements both indicated good electrical properties that can be specifically tailored by changing the layer thickness.
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U2 - 10.1111/j.1151-2916.1998.tb02633.x
DO - 10.1111/j.1151-2916.1998.tb02633.x
M3 - Article
AN - SCOPUS:0032165326
SN - 0002-7820
VL - 81
SP - 2371
EP - 2380
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 9
ER -