MOCVD of TiO2 thin films using a heteroleptic titanium complex: Precursor evaluation and investigation of optical, photoelectrochemical and electrical properties

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Manish Banerjee - , Ruhr University Bochum (Author)
  • Van Son Dang - , Ruhr University Bochum (Author)
  • Michal Bledowski - , Ruhr University Bochum (Author)
  • Radim Beranek - , Ruhr University Bochum (Author)
  • Hans Werner Becker - , Ruhr University Bochum (Author)
  • Detlef Rogalla - , Ruhr University Bochum (Author)
  • Eugen Edengeiser - , Ruhr University Bochum (Author)
  • Martina Havenith - , Ruhr University Bochum (Author)
  • Andreas D. Wieck - , Ruhr University Bochum (Author)
  • Anjana Devi - , Ruhr University Bochum (Author)

Abstract

A new heteroleptic titanium precursor with a mixed oxygen/nitrogen coordination sphere [Ti(dmap)2(NMe2)2] (Hdmap=1-dimethylamino-2-propanol) is synthesized by a simple elimination reaction on tetrakis-dimethylaminotitanium(IV) [Ti(NMe2)4]. The compound shows encouraging results in terms of chemical and thermal stability compared to the parent alkyl amide [Ti(NMe2)4], and is therefore more suitable for MOCVD applications. TiO2 thin films are grown on Si(100) and ITO-coated borosilicate glass substrates via MOCVD in the temperature range 500-800°C. The deposition temperature has a significant effect on the phase and microstructure of the TiO2 films obtained, which influences the functional properties. The optical bandgaps of the films are in the range 2.92-3.36eV. The best photocurrent response (1.5mAcm-2 under AM 1.5G conditions) in aqueous electrolytes is observed for films grown at 700°C having improved crystallinity and porous columnar structure.

Details

Original languageEnglish
Pages (from-to)224-233
Number of pages10
JournalChemical Vapor Deposition
Volume20
Issue number7-9
Publication statusPublished - 1 Sept 2014
Peer-reviewedYes
Externally publishedYes

Keywords

Keywords

  • MOCVD, optical bandgap, photoelectrochemical properties, TiO thin films, [Ti(dmap)(NMe)]