Surface dielectric tunnel barrier induced by Mn doping in SnO_2 micro- and nanostructures

Electrical properties of undoped and Mn doped SnO2 microplates and rods are studied by electron beam induced current (EBIC) in a scanning electron microscope (SEM), and I-V curves acquired at room temperature. AFM measurements reveal the formation of numerous terraces at the (-101) surface of the an...

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Detalhes bibliográficos
Autores: Maestre Varea, David, Cremades Rodríguez, Ana Isabel, Herrera, Manuel
Formato: artículo
Fecha de publicación:2018
País:España
Recursos:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/13086
Acesso em linha:https://hdl.handle.net/20.500.14352/13086
Access Level:acceso abierto
Palavra-chave:538.9
Beam-induced current
Grain-boundaries
Oxide
Photoluminescence
Nanowires
Films
Doping
Electron beam induced current
Microplate
SnO2
Física de materiales
Física del estado sólido
2211 Física del Estado Sólido
Descrição
Resumo:Electrical properties of undoped and Mn doped SnO2 microplates and rods are studied by electron beam induced current (EBIC) in a scanning electron microscope (SEM), and I-V curves acquired at room temperature. AFM measurements reveal the formation of numerous terraces at the (-101) surface of the analyzed Mn-doped SnO2 microplates, which also exhibit high carrier recombination processes at their central region, as confirmed by combined EBIC and cathodoluminescence (CL) measurements. A diffusion length for minority carriers about 205nm is obtained by EBIC measurements. Different electrical conduction mechanisms, such as Fowler-Nordheim, direct tunneling and Poole-Frenkel, are evaluated in the electrical analysis of the samples. Mn doped microplates show lower conductivity than the undoped microds. Moreover the height of the surface tunnel barrier is increased by Mn doping, as confirmed by the analysis of the I-V curves acquired under transversal configuration. A value of the relative dielectric constant E-r about 7.3 is estimated for the probed SnO2 microstructures.