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dc.contributor.advisorAlshareef, Husam N.
dc.contributor.authorXu, Xiangming
dc.date.accessioned2020-12-09T11:29:24Z
dc.date.available2020-12-09T11:29:24Z
dc.date.issued2020-10-26
dc.identifier.citationXu, X. (2020). Wafer-scale growth method of single-crystalline 2D MoS2 film for high-performance optoelectronics. KAUST Research Repository. https://doi.org/10.25781/KAUST-8634E
dc.identifier.doi10.25781/KAUST-8634E
dc.identifier.urihttp://hdl.handle.net/10754/666313
dc.description.abstract2D semiconductors are one of the most promising materials for next-generation electronics. Realizing continuous 2D monolayer semiconductors with single-crystalline structure at the wafer scale is still a challenge. We developed an epitaxial phase conversion (EPC) process to meet these requirements. The EPC process is a two-step process, where the sulfurization process was carried out on pre-deposited Mo-containing films. Traditionally, two-step processes for 2D MoS2 and other chalcogenides have suffered low-quality film and non-discontinuity at monolayer thickness. The reason was regarded as the low lattice quality of precursor film. The EPC process solves these problems by carefully preparing the precursor film and carefully controlling the sulfurization process. The precursor film in the EPC process is epitaxial MoO2 grown on 2″ diameter sapphire substrate by pulsed laser deposition. This epitaxial precursor contains significantly fewer defects compared to amorphous precursor films. Thus fewer defects are inherited by the EPC MoS2 film. Therefore, EPC MoS2 film quality is much better. The EPC prepared monolayer MoS2 devices to show field-effect mobility between 10 ~ 30 cm2·V-1s-1, which is the best among the two-step process. We also developed a CLAP method further to reduce the defects in the precursor oxide film; thus, in-plane texture in the thicker MoS2 film was eliminated, and a single-crystalline structure was obtained in the wafer-scale MoS2 films. The potentially feasible technique to further improve the 2D film quality is pointed out for our next research plan. Meanwhile, the epitaxial phase conversion process was proposed to be as a universal growth method. Last but not least, we demonstrate several potential applications of the wafer-scale single-crystalline MoS2 film we developed, such as logic circuits, flexible electronics, and seeding layer of van der Waal or remote epitaxial growth.
dc.language.isoen
dc.subject2D MoS2
dc.subjectWafer-scale
dc.subjectEpitaxial phase conversion
dc.subjectMicroelectronics
dc.subjectTransistor
dc.subjectCapping layer annealing process
dc.titleWafer-scale growth method of single-crystalline 2D MoS2 film for high-performance optoelectronics
dc.typeDissertation
dc.contributor.departmentPhysical Science and Engineering (PSE) Division
thesis.degree.grantorKing Abdullah University of Science and Technology
dc.contributor.committeememberDa Costa, Pedro M. F. J.
dc.contributor.committeememberSalama, Khaled N.
dc.contributor.committeememberManuel, Quevedo-Lopez
thesis.degree.disciplineMaterial Science and Engineering
thesis.degree.nameDoctor of Philosophy
refterms.dateFOA2020-12-09T11:29:25Z
kaust.request.doiyes


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