Registration Number
0209U010687,
0108U006020
, R & D reports
Title
Doped oxides thin films - promising materials for optoelectronic and spintronic devices
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Head
Bilichuk Sergiy,
Registration Date
28-12-2009
Organization
Yuri Fedkovych Chernivtsi National University
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In the framework of the project, we determined the optimal regimes to obtain SnO2 and ZnO oxide films (both non-doped and doped with 3d-elements) by reactive and radio-frequency magnetron sputtering. The method of pulverization with further pyrolysis was used to deposit the films of SnO2:Mn and SnO2:Co with specific resistivity р = 8·10-3 - 2*106 ·cm, structurally homogeneous for a thickness d = 0.2 m and ZnO:Mn with р = 8 - 106 ·cm with thickness d = 0.1 m. We studied annealing kinetics for SnО2 films deposited by sputtering over non pre-heated and pre-heated substrates. Basing on the analysis of temperature dependence of specific resistivity we determined the possible microcrystalline structure, suggesting that carriers mean free path is of the same order of magnitude as the grain size of the material. We have determined the required conditions for successful formation of Co/СdTe, Co/СdМпTe, Cr/n-CdTe, Cr/n-CdTe:Sc, Ni/n-Si, Ni/ZnMnO, and ZnО:Со/n-GaP structures. It was found out that decrease of carrier concentration for almost three orders of magnitude in the base area of n-CdTe:Sc was due to formation of cadmium vacancies as intrinsic defects of acceptor type. Investigation of current-voltage and capacitance-voltage curves of the obtained structures allowed to determine the main parameters of the junction region, such as the height of the potential barrier and thickness of space charge region in the base semiconductor. We have analyzed the carrier transport phenomena in the structures magnetic metal / semiconductor. It was found that the carrier injection mechanism in Cr/n-CdTe:Sc contact depends on the temperature significantly. In particular, for room temperature and above (T=295-333K) the dominating mechanism is a diffusion through the barrier; for low temperatures (T=77-133K) there is carrier diffusion (for U 0.12V) and tunneling. The reverse current is formed mainly by the thermal motion of the carriers and tunneling current.
Product Description
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Білічук Сергій Васильович
Горлей Петро Миколайович
Константинович Іван Аурелович
Орлецький Іван Григорович
Фрасуняк Василь Михайлович
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2020-04-02
