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[{"key": "dc.contributor.advisor", "value": "Maasilta, Ilari", "language": null, "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.advisor", "value": "Geng, Zhuoran", "language": null, "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Hakanen, Toivo", "language": "", "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2024-06-18T05:53:18Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2024-06-18T05:53:18Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2024", "language": null, "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/95982", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "In this thesis, the patterning techniques of lithium-niobate-on-insulator silicon chips were investigated to create free-standing membrane platforms of LiNbO3 (lithium niobate) that are separated by a submicron gap for cryogenic acoustic phonon tunneling measurements. A three-layer mask of mr-PosEBR - Al2O3 - Cr was utilized in LiNbO3 dry etching to achieve good gap edge quality. An estimated Cr to LiNbO3 selectivity of 0.3 was achieved with an estimated LiNbO3 etch rate of 6 nm/min and edge wall verticality of 56\u00b0. HF vapor was used to etch SiO2 from underneath LiNbO3 and release membrane platforms from bulk, and evaporated Al2O3 was used to protect devices from unwanted corrosion. Vapor etch had a SiO2 etch rate of 0.5 \u00b5m/min, which is much higher than values found in literature. Ultimately, sample fabrication failed because the Al2O3 coating on top of membranes didn\u2019t protect the measurement devices fabricated on top of LiNbO3 platforms from HF corrosion. Numerical calculations showed that the heat flux from the acoustic phonon tunneling is the strongest in the crystallographic X-direction, with a value of 5.2 \u00b5W/m2 for two semi-infinite plates separated by a 200 nm gap at 0.1 K. Heat fluxes in the Yand Z-directions were 5.0 \u00b5W/m2 and 2.1 \u00b5W/m2 , respectively, under the same conditions. A similar trend was observed with tunneled power transmittance in the Y- and Z-directions: the Y-direction had higher power transmittance across all incident mode-tunneled mode pairs compared to the Z-direction.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "T\u00e4ss\u00e4 Pro Gradu -tutkielmassa tutkittiin piisirun eristeen p\u00e4\u00e4lle kasvatetun litiumniobaattikerroksen (LNOI, lithium-niobate-on-insulator) kuviointitekniikoita. Kuviontitekniikoilla oli tarkoitus valmistaa itse\u00e4\u00e4n kannattelevia alustoja LiNbO3- kalvoista alle mikrometrin levyisen raon erottamana, joilla voisi tehd\u00e4 kryogenisi\u00e4 mittauksia akustisten fononien tunneloinnista. LiNbO3 kuivaetsauksessa k\u00e4ytettiin kolmikerroksista mr-PosEBR - Al2O3 - Cr -kovaetsausmaskia, jolla saavutettiin hyv\u00e4 raon reunan j\u00e4lki. LiNbO3 etsauksen selektiivisyyden arvioitiin olevan 0,3 Cr suhde LiNbO3 reseptill\u00e4, mink\u00e4 LiNbO3 etsausnopeudeksi arvoitiin 6 nm/min ja reunan sein\u00e4n kaltevuudeksi 56\u00b0. LiNbO3 alustat vapautettiin SiO2-kontaktista etsaamallla SiO2 HF-h\u00f6yryetsauksella. H\u00f6yrystetty\u00e4 Al2O3 k\u00e4ytettiin suojaamaan sirulle rakennettuja mittalaiteita korroosiolta. HF-h\u00f6yry etsasi SiO2 0,5 \u00b5m/min nopeudella, mik\u00e4 on huomattavasti nopeampaa kuin mit\u00e4 kirjallisuudesta l\u00f6ytyy. Loppujen lopuksi mitattavien n\u00e4ytteiden valmistus ep\u00e4onnistui siihen, ett\u00e4 suojaava Al2O3-kerros ei oikeasti suojannut LiNbO3-alustojen p\u00e4\u00e4lle rakennettuja mittalaitteita HF-korroosiolta. Numeeriset laskelmat osoittivat, ett\u00e4 tunneloituvien fononien l\u00e4mp\u00f6vuo on voimakkaimmillaan kristallografisessa X-suuntaan. L\u00e4mp\u00f6vuo oli 5,2 \u00b5W/m2 kahdelle puoli\u00e4\u00e4rett\u00f6m\u00e4lle kappaleelle 200 nm raon erottamana 0,1 K l\u00e4mp\u00f6tilassa. L\u00e4mp\u00f6vuot Y- ja Z-suunnissa olivat vastaavasti 5,0 \u00b5W/m2 ja 2,1 \u00b5W/m2 samoissa olosuhteissa. Samanlainen trendi havaittiin tunneloituvien fononien siirt\u00e4m\u00e4ll\u00e4 teholla Y- ja Z-suunnissa: tunneloituneet fononit siirsiv\u00e4t enemm\u00e4n tulevien fononien tehoa Y-suunnassa Z-suuntaan verrattuna.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Miia Hakanen (mihakane@jyu.fi) on 2024-06-18T05:53:18Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2024-06-18T05:53:18Z (GMT). No. of bitstreams: 0\n Previous issue date: 2024", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "71", "language": "", "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.language.iso", "value": "eng", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "acoustic phonons", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "piezoelectricity", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "phonon tunneling", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "lithium niobate", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "LiNbO3", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Acoustic phonon tunneling in LiNbO3", "language": "", "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-202406184748", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Matemaattis-luonnontieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Department of Physics", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Fysiikan laitos", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Physics", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Fysiikka", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "openAccess", "language": null, "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "4021", "language": null, "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "fononit", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "nanorakenteet", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "phonons", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "nanostructures", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}]
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