Lanthanum-magnesium and lanthanum-manganese donor-acceptor-codoped semiconducting barium titanate
- Materials Research Lab., Industrial Technology Research Inst., Chutung (TW)
- National Tsing Hua Univ., Hsinchu (Taiwan)
BaTiO{sub 3} powder doped with La donor and codoped with Mn or Mg acceptor was sintered at 1350{degrees}C/1 h in air. For La-doped BaTiO{sub 3} the room-temperature resistivity decreased to a minimum at (La{sup 3 +}) {approximately} 0.15 mol%. For La-Mn-codoped BaTiO{sub 3}, the minimum resistivity occurred at (La{sup 3 +}) {minus} 2(Mn{sup 2 +}) {approximately} 0.15 mol%. When the ceramic was changed to a fine grained insulator by high donor doping ((La{sup 3 +}) {gt} 0.15 mol%), its semiconductivity was restored, and the relatively homogeneous, coarse-grained microstructure recurred by codoping with either Mg or Mn acceptor, with the transition at (La{sup 3 +}) {minus} 2(Mg{sup 2 +}) = 0.15 mol% or (La{sup 3 +}) {minus} 2(Mn{sup 2 +}) = 0.15 mol%. The analogy of a compensation effect between La-Mn- and La-Mg-codoped BaTiO{sub 3} suggested that Mn acceptor added to BaTiO{sub 3} exists as Mn{sup 2 +} ion in the bulk grain region; its influence on the positive temperature coefficient of resistivity behavior is then discussed.
- OSTI ID:
- 6785818
- Journal Information:
- Journal of the American Ceramic Society; (USA), Vol. 73:2; ISSN 0002-7820
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BARIUM OXIDES
PHASE STUDIES
TITANATES
ELECTRICAL PROPERTIES
LANTHANUM COMPOUNDS
MAGNESIUM ADDITIONS
MANGANESE ADDITIONS
MICROSTRUCTURE
SEMICONDUCTOR MATERIALS
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
BARIUM COMPOUNDS
CHALCOGENIDES
CRYSTAL STRUCTURE
MAGNESIUM ALLOYS
MANGANESE ALLOYS
MATERIALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
360603 - Materials- Properties
360204 - Ceramics
Cermets
& Refractories- Physical Properties