Low temperature growth, characterization and applications of rf-sputtered SrTiO3 and BaSrTiO3 thin films

Simple item page
buir.advisorBıyıklı, Necmi
dc.contributor.authorBayrak, Türkan
dc.date.accessioned2016-04-27T06:17:28Z
dc.date.available2016-04-27T06:17:28Z
dc.date.copyright2016-03
dc.date.issued2016-03
dc.date.submitted17-03-2016
dc.departmentGraduate Program in Materials Science and Nanotechnologyen_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (leaves 100-114).en_US
dc.descriptionThesis (M.S.): Bilkent University, Materials Science and Nanotechnology Program, İhsan Doğramacı Bilkent University, 2016.en_US
dc.description.abstractAmong the several perovskite ferroelectric oxides, SrTiO3 (STO) and BaSrTiO3 (BST) thin lms have attracted signi cant attention due to their potential applications in oxide-based electronics. However, reliability and performance of STO and BST thin lms depend usually on the precise knowledge of microstructure, as well as optical and electrical properties. STO and BST thin lms were deposited at room-temperature on Si (100), UVgrade fused silica, quartz substrates and TiO2 nano bers by radio frequency (RF) magnetron sputtering using di erent plasma power, oxygen mixing ratios (OMRs) and deposition pressure levels. As-deposited thin lms showed amorphous-like nanocrystalline microstructure almost independent of the deposition conditions. In uence of post-deposition annealing at various temperatures of RF sputtered STO thin lms were also investigated. All lms were found to be highly transparent (>75%) in the visible region, and both STO and BST lms exhibited well de ned main absorption edges: the calculated indirect and direct band gaps for STO lms were in the range of 2.32 to 4.55 eV. The refractive index of the STO lms increased with OMR and post-deposition annealing for 3 mTorr deposition for STO, BST and STO annealing study. However, there is no correlation for 5 mTorr deposition. The refractive indices of BST lms were in the range of 1.90-2.07 at 550 nm depending on their deposition conditions. The optical band gap of the BST lms were calculated the ranging in 3.60 to 4.30 eV. Electrical dielectric constant values of the STO thin lms were extracted from frequency or voltage dependent capacitance measurements using micro-fabricated Ag/STO/p-Si device structures. High dielectric constant values reaching up to 100 were obtained. All STO samples exhibited more than 2.5 C/cm2 charge storage capacity and low dielectric loss (less than 0.07 at 100 kHz). Post-deposition annealing at 800oC for 1 h resulted in polycrystalline BST thin lms with increased refractive indices and dielectric constants, along with reduced optical transmission values. Frequency dependent dielectric constants were found to be in the range of 46-72, and the observed leakage current was very small,less than 1 A. Our experimental results show that these low temperature grown STO and BST lms have the potential for various electrical applications.en_US
dc.description.degreeM.S.en_US
dc.description.statementofresponsibilityby Türkan Bayrak.en_US
dc.embargo.release2018-03-17
dc.format.extentxx, 115 leaves : illustrations, charts.en_US
dc.identifier.itemidB152941
dc.identifier.urihttp://hdl.handle.net/11693/28990
dc.language.isoEnglishen_US
dc.publisherBilkent Universityen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectNanocrystallineen_US
dc.subjectPolycrystallineen_US
dc.subjectAnnealingen_US
dc.subjectSputter depositionen_US
dc.subjectRoom temperature depositionen_US
dc.subjectButter y curveen_US
dc.subjectFerroelectricen_US
dc.subjectDielectric constanten_US
dc.subjectPhotocatalytic activityen_US
dc.subjectBarium strontium titanate thin filmen_US
dc.subjectStrontium titanate thin filmen_US
dc.titleLow temperature growth, characterization and applications of rf-sputtered SrTiO3 and BaSrTiO3 thin filmsen_US
dc.title.alternativeSrtio3 ve Basrtio3 ince filmlerin düşük sıcaklıkta depolanması, karakterizasyonu ve uygulamalarıen_US
dc.typeThesisen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
final_tbayrak_Msc_march2016.pdf
Size:
64.35 MB
Format:
Adobe Portable Document Format
Description:
Full printable version
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Graduate Program in Materials Science and Nanotechnology - Master's degree