Japanese Journal of Applied Physics · 1994 · 55 citations · 3 references
Natural SciencesMaterials EngineeringMaterials ScienceCeramic MaterialsMaterials ChemistryThin FilmsChemical Vapor DepositionInorganic MaterialsPhysical Vapor DepositionSemiconductor Device MaterialsThin-film DepositionTransition Metal ChemistryChemical Vapor Deposition MaterialsChemical Vapor Deposition PrecursorsDielectric ConstantMelting PointMetalorganic Chemical Vapor DepositionStrontium Barium TitanateStrontium SaltsThin Oxide Films
Novel Sr source materials for metalorganic chemical vapor deposition (MOCVD) of SrTiO 3 have been developed. They were synthesized by adding amine, triethylenetetramine (trien) or tetraethylenepentamine (tetraen), to bis-dipivaloylmethanato strontium ( Sr(DPM) 2 , or strontium-bis-2,2,6,6-tetramethyl-3,5-heptanedionate). The new sources, Sr(DPM) 2 -trien 2 and Sr(DPM) 2 -tetraen 2 , have a low melting point (43–75° C), and are liquid in phase when they are vaporized at 120–130° C. SrTiO 3 thin films were prepared on Pt/Ta/ SiO 2 /Si substrates by MOCVD using the new Sr sources. The dielectric constant of films prepared with Sr(DPM) 2 -trien 2 was 215 for 125 nm thick SrTiO 3 films, and leakage current densities were below 10 -6 A/cm 2 at 1.5 V for 80 nm thick SrTiO 3 films. The new Sr sources did not change in quality after 20-time heat cycles between room temperature and 130° C in Ar atmosphere at 40 Torr.
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