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Graphene transfer methods for high quality graphene field effect transistors
Tesař, Jan ; Kormoš, Lukáš (referee) ; Procházka, Pavel (advisor)
This bachelor thesis is focused on the influence of different graphene transfer methods on its quality. Graphene layers were grown by Chemical Vapour Deposition (CVD) method. The quality characterization of subsequently transfered graphene is based on the measurement of charge carrier mobility which has been performed on the field-effect transistors fabricated by transferring of graphene layers onto Si/SiO$_2$ surface. Chemical etching and electrolytic delamination are the transfer methods that are being compared in this thesis. Results of the measurements showed that graphene layers transferred by electrolytic delamination exhibit approximately four times higher charge carrier mobility than those transferred by the chemical etching method.
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Fabrication of Graphene and Study of its Physical Properties
Procházka, Pavel ; Rezek, Bohuslav (referee) ; Kalbáč,, Martin (referee) ; Dub, Petr (advisor)
This doctoral thesis is focused on the preparation of graphene layers by Chemical Vapor Deposition (CVD) and their utilization for fabrication and characterization of field effect transistors. The theoretical part of the thesis deals with different methods of graphene production and measurement of its transport properties. In the first part of the experimental section the growth of polycrystalline graphene and individual graphene crystals with sizes up to 300 m is investigated. Further, graphene layer was also grown on an atomically flat copper foils, which were fabricated in order to achieve the growth of graphene of higher quality. Subsequently, the transport properties of field effect transistors produced from the grown layers were measured. The last two chapters deal with a doping of graphene layer by gallium atoms and X-ray radiation. Whereas the deposition of gallium atoms on the graphene surface causes chemical doping of graphene layer by charge transfer, X-ray irradiation of graphene field effect transistors induces the ionization of positively charged defects in dielectrics, which electrostatically dope a graphene layer.
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Graphene-on-silicon Schottky junction solar cells
Zahradníček, Radim ; Drbohlavová,, Jana (referee) ; Mach, Jindřich (advisor)
This diploma thesis concerns itself with fabrication and characterization of Schottky solar cell on the graphene/silicon interface. Schottky solar cells were manufactured using a front collector electrode from gold, silver and carbon. On the graphene/silicon interface of the Schottky solar cell an interlayer of Al2O3 or SiO2. For the purpose of IV characterization of the manufactured Schottky solar cell a measuring apparatus was assembled.
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Preparation of graphene membranes for Ga deposition
Severa, Jiří ; Bartošík, Miroslav (referee) ; Mach, Jindřich (advisor)
This bachelor’s thesis deals with the production of graphene membranes, which would be suitable for the deposition of gallium atoms. In the first part is characterized graphene. The second part is focused on preparation and improvement the production of graphene layers via atomically flat Cu foils. In the third part are described graphene membranes, techniques of their production and specific applications of graphene membranes. The fourth part introduced interface between gallium and graphene layers. The fifth part is the practical part. Graphene was grown on different Cu foils which resulted in higher quality graphene grown on smooth foils. Subsequently, the production of graphene membranes and deposition of gallium atoms were done.
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Preparation of graphene membranes for Ga deposition
Severa, Jiří ; Bartošík, Miroslav (referee) ; Mach, Jindřich (advisor)
This bachelor’s thesis deals with the production of graphene membranes, which would be suitable for the deposition of gallium atoms. In the first part is characterized graphene. The second part is focused on preparation and improvement the production of graphene layers via atomically flat Cu foils. In the third part are described graphene membranes, techniques of their production and specific applications of graphene membranes. The fourth part introduced interface between gallium and graphene layers. The fifth part is the practical part. Graphene was grown on different Cu foils which resulted in higher quality graphene grown on smooth foils. Subsequently, the production of graphene membranes and deposition of gallium atoms were done.
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Graphene transfer methods for high quality graphene field effect transistors
Tesař, Jan ; Kormoš, Lukáš (referee) ; Procházka, Pavel (advisor)
This bachelor thesis is focused on the influence of different graphene transfer methods on its quality. Graphene layers were grown by Chemical Vapour Deposition (CVD) method. The quality characterization of subsequently transfered graphene is based on the measurement of charge carrier mobility which has been performed on the field-effect transistors fabricated by transferring of graphene layers onto Si/SiO$_2$ surface. Chemical etching and electrolytic delamination are the transfer methods that are being compared in this thesis. Results of the measurements showed that graphene layers transferred by electrolytic delamination exhibit approximately four times higher charge carrier mobility than those transferred by the chemical etching method.
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|
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Fabrication of Graphene and Study of its Physical Properties
Procházka, Pavel ; Rezek, Bohuslav (referee) ; Kalbáč,, Martin (referee) ; Dub, Petr (advisor)
This doctoral thesis is focused on the preparation of graphene layers by Chemical Vapor Deposition (CVD) and their utilization for fabrication and characterization of field effect transistors. The theoretical part of the thesis deals with different methods of graphene production and measurement of its transport properties. In the first part of the experimental section the growth of polycrystalline graphene and individual graphene crystals with sizes up to 300 m is investigated. Further, graphene layer was also grown on an atomically flat copper foils, which were fabricated in order to achieve the growth of graphene of higher quality. Subsequently, the transport properties of field effect transistors produced from the grown layers were measured. The last two chapters deal with a doping of graphene layer by gallium atoms and X-ray radiation. Whereas the deposition of gallium atoms on the graphene surface causes chemical doping of graphene layer by charge transfer, X-ray irradiation of graphene field effect transistors induces the ionization of positively charged defects in dielectrics, which electrostatically dope a graphene layer.
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Graphene-on-silicon Schottky junction solar cells
Zahradníček, Radim ; Drbohlavová,, Jana (referee) ; Mach, Jindřich (advisor)
This diploma thesis concerns itself with fabrication and characterization of Schottky solar cell on the graphene/silicon interface. Schottky solar cells were manufactured using a front collector electrode from gold, silver and carbon. On the graphene/silicon interface of the Schottky solar cell an interlayer of Al2O3 or SiO2. For the purpose of IV characterization of the manufactured Schottky solar cell a measuring apparatus was assembled.
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