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dc.contributor.advisorAzarian, Michael H.en_US
dc.contributor.authorBevensee, Helmut Manfreden_US
dc.date.accessioned2016-06-22T06:21:21Z
dc.date.available2016-06-22T06:21:21Z
dc.date.issued2016en_US
dc.identifierhttps://doi.org/10.13016/M2RN4J
dc.identifier.urihttp://hdl.handle.net/1903/18425
dc.description.abstractPolymer aluminum electrolytic capacitors were introduced to provide an alternative to liquid electrolytic capacitors. Polymer electrolytic capacitor electric parameters of capacitance and ESR are less temperature dependent than those of liquid aluminum electrolytic capacitors. Furthermore, the electrical conductivity of the polymer used in these capacitors (poly-3,4ethylenedioxithiophene) is orders of magnitude higher than the electrolytes used in liquid aluminum electrolytic capacitors, resulting in capacitors with much lower equivalent series resistance which are suitable for use in high ripple-current applications. The presence of the moisture-sensitive polymer PEDOT introduces concerns on the reliability of polymer aluminum capacitors in high humidity conditions. Highly accelerated stress testing (or HAST) (110ºC, 85% relative humidity) of polymer aluminum capacitors in which the parts were subjected to unbiased HAST conditions for 700 hours was done to understand the design factors that contribute to the susceptibility to degradation of a polymer aluminum electrolytic capacitor exposed to HAST conditions. A large scale study involving capacitors of different electrical ratings (2.5V – 16V, 100µF – 470 µF), mounting types (surface-mount and through-hole) and manufacturers (6 different manufacturers) was done to determine a relationship between package geometry and reliability in high temperature-humidity conditions. A Geometry-Based HAST test in which the part selection limited variations between capacitor samples to geometric differences only was done to analyze the effect of package geometry on humidity-driven degradation more closely. Raman spectroscopy, x-ray imaging, environmental scanning electron microscopy, and destructive analysis of the capacitors after HAST exposure was done to determine the failure mechanisms of polymer aluminum capacitors under high temperature-humidity conditions.en_US
dc.language.isoenen_US
dc.titleThe Effect of Package Geometry on Moisture Driven Degradation of Polymer Aluminum Capacitorsen_US
dc.typeThesisen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.contributor.departmentMechanical Engineeringen_US
dc.subject.pqcontrolledEngineeringen_US
dc.subject.pquncontrolledAluminumen_US
dc.subject.pquncontrolledCapacitoren_US
dc.subject.pquncontrolledElectronicsen_US
dc.subject.pquncontrolledPEDOTen_US
dc.subject.pquncontrolledPolymeren_US
dc.subject.pquncontrolledReliabilityen_US


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