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dc.contributor.advisorSivananthan, Sivalingamen_US
dc.contributor.authorBrown, Alexander E.en_US
dc.date.accessioned2016-02-16T23:04:16Z
dc.date.available2016-02-16T23:04:16Z
dc.date.created2015-12en_US
dc.date.issued2016-02-16
dc.date.submitted2015-12en_US
dc.identifier.urihttp://hdl.handle.net/10027/20187
dc.description.abstractModern detector materials used for infrared (IR) imaging purposes contain complex multi-layered architectures, making more robust characterization techniques necessary. In order to determine mutli-carrier transport properties in the presence of mixed conduction, variable-field Hall characterization can be performed and then analyzed using mobility spectrum analysis to extract parameters of interest. Transport parameters are expected to aid in modeling and simulation of materials and can be used in optimization of particular problem areas. The performances of infrared devices ultimately depend on transport mechanisms, so an accurate determination becomes paramount. This work focuses on the characterization of two materials at the forefront of IR detectors; incumbent, tried and true, HgCdTe technologies and emergent III-V based superlattice structures holding much promise for future detector purposes. Ex-situ doped long-wave planar devices and in-situ doped mid-wave dual-layer heterojunctions (P+/n architecture) HgCdTe structures are explored with regards to substrate choice, namely lattice-matched CdZnTe and lattice-mismatched Si or GaAs. A detailed study of scattering mechanisms reveal that growth on lattice-mismatched substrates leads to dislocation scattering limited mobility at low temperature, correlating with extrinsically limited minority carrier lifetime and excesses diode tunneling current, resulting in overall lower performance. Mobility spectrum analysis proves to be an effective diagnostic on performance as well as providing insight in surface, substrate-interface, and minority carrier transport. Two main issues limiting performance of III-V based superlattices are addressed; high residual doping backgrounds and surface passivation. Mobility spectrum analysis proves to be a reliable method of determining background doping levels. Modest improvements are obtained via post-growth thermal annealing, but results suggest future efforts should be placed upon growth improvements. Passivation efforts using charged electret dielectric show promise but further refinements would be needed. Thiol passivation is identified as a successful passivant of Be-doped p-type InAs/GaSb long-wave absorbers using mobility spectrum analysis, correlating with fabricated device dark current. Mobility spectrum analysis demonstrates it will be indispensable in future development of III-V material.en_US
dc.language.isoenen_US
dc.rightsen_US
dc.rightsCopyright 2015 Alexander E. Brownen_US
dc.subjectMobility Spectrum Analysisen_US
dc.subjectInfrareden_US
dc.subjectTransporten_US
dc.subjectHgCdTeen_US
dc.subjectInAs/GaSben_US
dc.subjectInAs/InAsSben_US
dc.titleApplication of Mobility Spectrum Analysis to Modern Multi-layered IR Device Materialen_US
thesis.degree.departmentPhysicsen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.grantorUniversity of Illinois at Chicagoen_US
thesis.degree.levelDoctoralen_US
thesis.degree.namePhD, Doctor of Philosophyen_US
dc.type.genrethesisen_US
dc.contributor.committeeMemberGrein, Christophen_US
dc.contributor.committeeMemberYang, Zhengen_US
dc.contributor.committeeMemberAlmeida, Leo Anthonyen_US
dc.contributor.committeeMemberArias, Joseen_US
dc.type.materialtexten_US


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