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Published on: February 8, 2018
Lead monoxide α-PbO: electronic properties and point defect formation
J Berashevich1, O Semeniuk, O Rubel
1Thunder Bay Regional Research Institute, 290 Munro Street, Thunder Bay, ON, P7B 5E1, Canada. berashej@tbh.net
Summary
Polycrystalline lead oxide (PbO) exhibits high concentrations of oxygen and lead vacancies, significantly impacting its electronic properties. These defects dominate charge transport, explaining observed conductivity behaviors in electronic devices.
Area of Science:
- Materials Science
- Solid State Physics
- Computational Chemistry
Background:
- Polycrystalline lead oxide (PbO) is a material with potential electronic applications.
- Understanding its electronic properties and defect behavior is crucial for device optimization.
Purpose of the Study:
- To investigate the electronic properties of polycrystalline α-PbO.
- To study the formation and impact of native point defects in the α-PbO crystal lattice.
Main Methods:
- First-principles calculations were employed.
- Analysis of electronic band structure and defect states.
Main Results:
- The polycrystalline nature of α-PbO leads to a high concentration of oxygen and lead vacancies.
- Oxygen vacancies create deep electron traps (1.03 eV above valence band).
- Lead vacancies form shallow hole traps (0.1 eV above valence band).
Conclusions:
- Defect-related conductivity is the dominant charge transport mechanism in polycrystalline α-PbO.
- Ionization of oxygen vacancies explains the observed dark current decay in ITO/PbO/Au devices.
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