Origin of n- and p-type conductivity in undoped α-PbO: role of defects
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Bibliographic record
Abstract
First-principles calculations have been applied to study the crystallographic defects in α-PbO in order to understand an origin of n- and p-type conductivity in otherwise undoped α-PbO. It was found that deposition in an oxygen-deficient environment defined in our simulations by the Pb-rich/O-poor limit stimulates a formation of O vacancies and Pb interstitials both characterized by quite low formation energies ∼1.0 eV. The O vacancy, being occupied by two electrons, shifts the balance of electrons and holes between these two defects to an excess of electrons (four electrons against two holes) that causes n-type doping. For the Pb-poor/O-rich limit, an excess of oxygen triggers the formation of the O interstitials characterized by such a low formation energy that a spontaneous appearance of this defect is predicted. It is shown that the concentration of O interstitials is able to reach an extreme magnitude equal to the number of possible defect sites (∼10(22) cm(-3)). The localized state formed by the O interstitial is occupied by two holes and because there are no other defects in reasonable concentration to balance the hole redundancy, p-type doping is induced.
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Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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