title: Atomic Layer Deposition of p-Type Epitaxial Thin Films of Undoped and N-Doped Anatase TiO2.
abstract: Employing atomic layer deposition, we have grown p-type epitaxial undoped and N-doped anatase TiO2(001) thin films on c-axis Al2O3 substrate. From X-ray diffraction and transmission electron microscopy studies, crystallographic relationships between the film and the substrate are found to be (001)TiO2//(0001)Al2O3 and [1̅10]TiO2//[011̅0]Al2O3. N-doping in TiO2 thin films enhances the hole concentration and mobility. The optical band gap of anatase TiO2 (3.23 eV) decreases to 3.07 eV upon N-doping. The epitaxial films exhibit room-temperature ferromagnetism and photoresponse. A TiO2-based homojunction diode was fabricated with rectification from the p-n junction formed between N-doped p-TiO2 and n-TiO2.
authors.affiliation: Chemistry and Physics of Materials Unit, Sheikh Saqr Laboratory and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bangalore 560064, India.
authors.forename: K
authors.initials: K
authors.lastname: Vasu
authors.affiliation: Chemistry and Physics of Materials Unit, Sheikh Saqr Laboratory and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bangalore 560064, India.
authors.forename: M B
authors.initials: MB
authors.lastname: Sreedhara
authors.affiliation: Chemistry and Physics of Materials Unit, Sheikh Saqr Laboratory and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bangalore 560064, India.
authors.forename: J
authors.initials: J
authors.lastname: Ghatak
authors.affiliation: Chemistry and Physics of Materials Unit, Sheikh Saqr Laboratory and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bangalore 560064, India.
authors.forename: C N R
authors.initials: CN
authors.lastname: Rao
keywords: N-doped TiO2 thin films; atomic layer deposition; epitaxial thin films; p-type conductivity; photoresponse; p−n homojunction; room-temperature ferromagnetism