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Characterization of hydrogenated silicon thin films and diode structures with integrated silicon and germanium nanoparticles
Stuchlík, Jiří ; Fajgar, R. ; Remeš, Zdeněk ; Kupčík, Jaroslav ; Stuchlíková, Hana
P-I-N diode structures based on the thin films of amorphous hydrogenated silicon (a-Si:H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) technique were prepared with embedded Si and Ge nanoparticles. The Reactive Laser Ablation (RLA) of germanium target was used to cover the intrinsic a-Si:H layer by Ge NPs under a low pressure of the silane. The RLA was performed using focused excimer ArF laser beam under SiH4 background atmosphere. Reaction between ablated Ge NPs and SiH4 led to formation of Ge NPs covered by thin GeSi:H layer. The deposited NPs were covered and stabilized by a-Si:H layer by PECVD. Those two deposition processes were alternated repeatedly. Volt-ampere characteristics of final diode structures were measured in dark and under illumination as well as their electroluminescence spectra.
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Germanium and tin nanoparticles encapsulated in amorphous silicon matrix for optoelectronic application
Stuchlíková, The-Ha ; Remeš, Zdeněk ; Stuchlík, Jiří
The plasma enhanced chemical vapour deposition was combined with in situ deposition of Ge and Sn thin film by evaporation technique at surface temperature about 220 °C to form nanoparticles on the surface of hydrogenated silicon thin films to prepare diodes. Formation of nanoparticles was additionally stimulated by plasma treatment through a low pressure hydrogen glow discharge. The diodes based on PIN diode structures with and without the embedded Ge or Sn nanoparticles were characterized by temperature dependence of electrical conductivity, activation energy of conductivity, measurement of volt-ampere characteristics in dark and under solar illumination\n
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Characterization of hydrogenated silicon thin films and diode structures with integrated germanium nanoparticles
Stuchlík, J. ; Fajgar, R. ; Remeš, Z. ; Kupčík, Jaroslav ; Stuchlíková, H.
P-I-N diode structures based on the thin films of amorphous hydrogenated silicon (a-Si: H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) technique were prepared with embedded Si and Ge nanoparticles. The Reactive Laser Ablation (RLA) of germanium target was used to cover the intrinsic a-Si: H layer by Ge NPs under a low pressure of the silane. The RLA was performed using focused excimer ArF laser beam under SiH4 background atmosphere. Reaction between ablated Ge NPs and SiH4 led to formation of Ge NPs covered by thin GeSi: H layer. The deposited NPs were covered and stabilized by a-Si: H layer by PECVD. Those two deposition processes were alternated repeatedly. Volt-ampere characteristics of final diode structures were measured in dark and under illumination as well as their electroluminescence spectra.
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Characterization of hydrogenated silicon thin films and diode structures with integrated germanium nanoparticles
Stuchlík, Jiří ; Fajgar, Radek ; Kupčík, Jaroslav ; Remeš, Zdeněk ; Stuchlíková, The-Ha
Substrates with ZnO (or ITO) conductive layers were covered by thin film of a-Si:H deposited by PECVD technique. Under a turbo-molecular vacuum (10-4 Pa) the reactive laser ablation (RLA) was used to cover this a-Si:H thin film by germanium NPs. The RLA was performed using focused excimer ArF laser beam (193 nm, 100 mJ/pulse) under SiH4 background atmosphere (0.5 Pa). As a target the elemental germanium was used. Reaction between ablated Ge and silane led to formation of Ge NPs covered by thin SiGe layer. Then the deposited NPs were covered and stabilized by a-Si:H layer by PECVD. Those two deposition processes was alternated and applied a few times. The Si:H thin films with integrated Ge NPs were characterized by microscopic, spectroscopic and diffraction techniques. I-V characteristics of final diode structures without and under illumination were measured as well as their electroluminescence behaviour.
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The deposition of germanium nanoparticles on hydrogenated amorphous silicon.
Stuchlík, J. ; Volodin, V.A. ; Shklyaev, A.A. ; Stuchlikova, T.H. ; Ledinsky, M. ; Čermák, J. ; Kupčík, Jaroslav ; Fajgar, R. ; Mortet, V. ; More-Chevalier, J. ; Ashcheulov, P. ; Purkrt, A. ; Remeš, Z.
We reveal the mechanism of Ge nanoparticles (NPs) formation on the surface of the hydrogenated amorphous silicon (a-Si:H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) on ITO and a on boron doped nanocrystalline diamond (BDD). The coating of Ge NPs on a-Si:H was performed by molecular beam epitaxy (MBE) at temperatures up to 450 degrees C. The Ge NPs were characterized by Raman spectroscopy, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The nanocrystalline Ge particles are conglomerates of nanocrystals of size 10-15 nm and quantum dots (QDs) with size below 2 nm embedded in amorphous Ge phase. After coating with Ge NPs the a-Si:H thin films show better adhesion on BDD substrates then on ITO substrates.
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The deposition of germanium nanoparticles on hydrogenated amorphous silicon
Stuchlík, Jiří ; Volodin, V.A. ; Shklyaev, A.A. ; Stuchlíková, The-Ha ; Ledinský, Martin ; Čermák, Jan ; Kupčík, Jaroslav ; Fajgar, Radek ; Mortet, Vincent ; More Chevalier, Joris ; Ashcheulov, Petr ; Purkrt, Adam ; Remeš, Zdeněk
We reveal the mechanism of Ge nanoparticles (NPs) formation on the surface of the hydrogenated amorphous silicon (a-Si:H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) on ITO and a on boron doped nanocrystalline diamond (BDD). The coating of Ge NPs on a-Si:H was performed by molecular beam epitaxy (MBE) at temperatures up to 450 °C. The Ge NPs were characterized by Raman spectroscopy, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The nanocrystalline Ge particles are conglomerates of nanocrystals of size 10-15 nm and quantum dots (QDs) with size below 2 nm embedded in amorphous Ge phase. After coating with Ge NPs the a-Si:H thin films show better adhesion on BDD substrates then on ITO substrates.
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Analysis of Services Provided to Citizens' Advisory
Martínek, Karel ; Sedláková, Jaroslava (advisor) ; Stuchlíková, Hedvika (referee)
The aim of the thesis is to do an analyze of services provided by the selected citizen advice and evaluation of the most common problems that clients turned up for help. In the introduction I define the basic theoretical and methodological basis of work. Subsequently, historical aspects will be generalized, which stood at the birth of a new citizen service. In another part I describe the term of counseling, focusing on the typology and principles. I specify the target group and the methodology of work with a client advisor. In conclusion, the theory will focus on the way to guarantee the quality of consulting services in relation to the standards of social services. In the practical part I bring near the role of management consulting citizen selected, the process of obtaining funding sources and ways of organizing work. Then I compare the differences in accounting and reporting against business entities. Further specifications will be made counseling process, with particular emphasis on the expertise of advisors. I do an analyze of services in terms of counseling and also I evaluate the social role of the state. The research part will seek both to confirm or refute the hypotheses set, while a suitable method of analyzing business advisors in dealing with clients in the selected clinic and evaluate the role of preventive counseling in the social phenomena studied. The outcome will be recommendations on how to improve business counseling and counselors themselves.
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