Matches in SemOpenAlex for { <https://semopenalex.org/work/W2981892244> ?p ?o ?g. }
Showing items 1 to 75 of
75
with 100 items per page.
- W2981892244 abstract "In this work, different ZnO interfaces were studied with respect to their performance in piezotronic applications. The electrical conductivity across metal – ZnO Schottky contacts as well as varistor-type ZnO-ZnO interfaces was measured as a function of uniaxial compressive stress. In addition, temperature-dependent measurements of the direct piezoelectric response of ZnO single crystals with and without the existence of a highly resistive space charge region were performed.The electrical conductivity across potential barriers at metal – ZnO Schottky contacts on either the Zn- or O-terminated surface of a bulk ZnO single crystal was measured under increasing uniaxial compressive stress. The generation of negative or positive piezoelectric polarization charges was found to increase or decrease the Schottky barrier height depending on the sign of the piezoelectric charge. The evolution of potential barrier height with increasing amount of positive piezoelectric charge was determined from I-V deconvolution techniques and allowed a comparison of the experimental data with different theoretical models. Measurements were performed on bulk ZnO single crystals to overcome shortcomings in existing literature in which studies are mainly based on metal-ZnO nanostructure contacts. Thereby the fundamental concept of the piezotronic effect could be confirmed and the current understanding is extended.Direct piezoelectric measurements on bulk ZnO single crystals with and without the existence of a highly resistive space charge region were performed as a function of temperature and loading frequency. A decreasing number of free charge carriers with decreasing temperature revealed a correlation between free charge carrier density and screening of the piezoelectric potential. An increase in attainable piezoelectric polarization with decreasing temperature was evident for the crystals with and without space charge region. In addition, the generation of a highly resistive space charge region in the vicinity of a Schottky contact allowed a measurement of the piezoelectric potential already at room temperature and for low loading frequencies. The shift of the attainable piezoelectric response to higher temperatures and lower loading frequencies due to the existence of a depletion region is of great importance for piezotronic applications. Besides metal-ZnO contacts, ZnO bicrystal interfaces were prepared by epitaxial solid-state transformation. The preparation process allows for both, a defined orientation of the polarization vector as well as tailoring of the defect state density at the ZnO-ZnO interface. Consequently, the interaction between positive and negative piezoelectric charges and the electrostatic potential barrier at the bicrystal interface could be systematically investigated. Stress-dependent conductivity measurements revealed a decreasing barrier for positive piezoelectric charges and an increasing potential barrier for negative piezoelectric charges. The magnitude of this coupling was compared to theoretical models as well as to experimental results obtained on metal-ZnO Schottky contacts. In comparison to the Schottky contact, potential barriers at ZnO-ZnO interfaces featured a much higher stress sensitivity. For the lowering case by positive piezoelectric charges an almost complete extinction of the electrostatic potential barrier could be achieved. The obtained results demonstrate the potential of individual ZnO-ZnO interfaces as promising alternative to metal-ZnO Schottky contacts in future piezotronic applications.By interrupting the epitaxial solid-state transformation process at different times during the high temperature treatment, single crystal – polycrystal structures with varying amount of remaining polycrystalline material in between two well oriented single crystals were prepared. Temperature-dependent conductivity measurements were applied to determine the influence of the high temperature treatment on the potential barrier height at varistor-type interfaces during bicrystal fabrication by epitaxial solid-state transformation. Furthermore, stress-dependent I-V measurements revealed extremely high stress sensitivities for structures with intermediate times of high temperature treatment. These measurements close the gap between piezotronic systems based on polycrystalline varistor ceramics and individual bicrystal interfaces and reveal the future potential of microstructural engineering for the development of varistor-based piezotronic devices." @default.
- W2981892244 created "2019-11-01" @default.
- W2981892244 creator A5043255195 @default.
- W2981892244 date "2019-01-01" @default.
- W2981892244 modified "2023-09-23" @default.
- W2981892244 title "Mechanically tuned conductivity in piezoelectric semiconductors" @default.
- W2981892244 hasPublicationYear "2019" @default.
- W2981892244 type Work @default.
- W2981892244 sameAs 2981892244 @default.
- W2981892244 citedByCount "0" @default.
- W2981892244 crossrefType "dissertation" @default.
- W2981892244 hasAuthorship W2981892244A5043255195 @default.
- W2981892244 hasConcept C100082104 @default.
- W2981892244 hasConcept C103132145 @default.
- W2981892244 hasConcept C104232198 @default.
- W2981892244 hasConcept C108225325 @default.
- W2981892244 hasConcept C121332964 @default.
- W2981892244 hasConcept C131540310 @default.
- W2981892244 hasConcept C135405054 @default.
- W2981892244 hasConcept C147120987 @default.
- W2981892244 hasConcept C147789679 @default.
- W2981892244 hasConcept C159985019 @default.
- W2981892244 hasConcept C16115445 @default.
- W2981892244 hasConcept C185592680 @default.
- W2981892244 hasConcept C192562407 @default.
- W2981892244 hasConcept C205200001 @default.
- W2981892244 hasConcept C26873012 @default.
- W2981892244 hasConcept C49040817 @default.
- W2981892244 hasConcept C62520636 @default.
- W2981892244 hasConcept C78434282 @default.
- W2981892244 hasConceptScore W2981892244C100082104 @default.
- W2981892244 hasConceptScore W2981892244C103132145 @default.
- W2981892244 hasConceptScore W2981892244C104232198 @default.
- W2981892244 hasConceptScore W2981892244C108225325 @default.
- W2981892244 hasConceptScore W2981892244C121332964 @default.
- W2981892244 hasConceptScore W2981892244C131540310 @default.
- W2981892244 hasConceptScore W2981892244C135405054 @default.
- W2981892244 hasConceptScore W2981892244C147120987 @default.
- W2981892244 hasConceptScore W2981892244C147789679 @default.
- W2981892244 hasConceptScore W2981892244C159985019 @default.
- W2981892244 hasConceptScore W2981892244C16115445 @default.
- W2981892244 hasConceptScore W2981892244C185592680 @default.
- W2981892244 hasConceptScore W2981892244C192562407 @default.
- W2981892244 hasConceptScore W2981892244C205200001 @default.
- W2981892244 hasConceptScore W2981892244C26873012 @default.
- W2981892244 hasConceptScore W2981892244C49040817 @default.
- W2981892244 hasConceptScore W2981892244C62520636 @default.
- W2981892244 hasConceptScore W2981892244C78434282 @default.
- W2981892244 hasLocation W29818922441 @default.
- W2981892244 hasOpenAccess W2981892244 @default.
- W2981892244 hasPrimaryLocation W29818922441 @default.
- W2981892244 hasRelatedWork W1987605395 @default.
- W2981892244 hasRelatedWork W2003328341 @default.
- W2981892244 hasRelatedWork W2010650563 @default.
- W2981892244 hasRelatedWork W2068084069 @default.
- W2981892244 hasRelatedWork W2070028278 @default.
- W2981892244 hasRelatedWork W2084324305 @default.
- W2981892244 hasRelatedWork W2086240697 @default.
- W2981892244 hasRelatedWork W2093895080 @default.
- W2981892244 hasRelatedWork W2157877712 @default.
- W2981892244 hasRelatedWork W2159061970 @default.
- W2981892244 hasRelatedWork W2511222351 @default.
- W2981892244 hasRelatedWork W2732416030 @default.
- W2981892244 hasRelatedWork W2915024977 @default.
- W2981892244 hasRelatedWork W2951445127 @default.
- W2981892244 hasRelatedWork W2986502910 @default.
- W2981892244 hasRelatedWork W3022292651 @default.
- W2981892244 hasRelatedWork W3095006636 @default.
- W2981892244 hasRelatedWork W3127679241 @default.
- W2981892244 hasRelatedWork W3174805116 @default.
- W2981892244 hasRelatedWork W3167250047 @default.
- W2981892244 isParatext "false" @default.
- W2981892244 isRetracted "false" @default.
- W2981892244 magId "2981892244" @default.
- W2981892244 workType "dissertation" @default.