Fabrication of two-dimensional molybdenum disulfide thin film also the study on optical characteristics and applications

Autor: Wei-De Chien, 簡瑋德
Rok vydání: 2017
Druh dokumentu: 學位論文 ; thesis
Popis: 105
The theme of this thesis is focused on the preparation and application of molybdenum disulfide (MoS2) film at the atomic layer. MoS2 thin films were deposited by chemical vapor deposition (CVD) method on the quartz and sapphire substrates. After the MoS2 thin film was synthesized, the morphology and film continuity of the substrate were analyzed by optical microscopy. Raman scattering was used to analyze the atomic vibration mode of the MoS2 thin film. The atom force microscopy (AFM) showed the epitaxial thickness are atomic layer. Optical properties of near-band-edge emission of MoS2 thin film using photoluminescence (PL) measurements in the temperature range between 12 K and 300 K. Bound exciton has been observed at low temperature. On the other hand, transmittance experiment observed free A exciton and free B exciton which are caused by electron spin splitting. At the application of MoS2 thin film, we used MoS2 to fabricate field effect transistor (FET) channel and photodetector. Beside, we studied of the optoelectronic structure for the MoS2 thin film and we made into photoconductive detectors. Finally, the oxygen plasma treatment was used to induce oxygen atoms into the MoS2. The better optoelectronic characteristics due to the plasma treatment doped MoS2. The tunneling current increases exponentially with doping concentration. By applying our fabricating method, the MoS2 thin film provides a new application of semiconductor device.
Databáze: Networked Digital Library of Theses & Dissertations