|
|
Study of photovoltaic nanostructures using microscopy methods
Hertl, Vít ; Valenta,, Jan (referee) ; Fejfar, Antonín (advisor)
V této diplomové práci je nejprve ve zkratce uvedena teorie fyziky solárních článků, kde jsou zmíněny klíčové procesy ovlivňující účinnost konverze slunečního záření na elektrickou energii. Dále je předložena rešerše o fotovoltaických nanostrukturách (nanodráty, nanokrystaly), jejichž implementací je možné účinnost solárních článků zvýšit. V přehledu experimentálních technik ke zkoumání fotovoltaických nanostruktur je důraz kladen zejména na korelativní měření pomocí SEM a AFM, vodivostního AFM, měření EBIC a mikroskopické měření elektroluminiscence. V experimentální části jsou předloženy výsledky měření struktur mikrokrystalického křemíku, vzorku hetero-přechodového Si solárního článku s kontakty na zadní straně (IBC-SHJ z projektu NextBase) a V-pitů vzorku InGaN/GaN kvantových jam. Měření elektroluminiscence bylo provedeno na vzorcích III-V polovodičů (InGaP, GaAs). Byly vypočítány jinak těžko dostupné charakteristiky III-V tandemových solárních článků pomocí elektroluminiscence a srovnání vlastností IBC-SHJ zjištěných pomocí mikroskopického měření elektroluminiscence a EBIC. Provedením experimentů bylo zjištěno, jakým způsobem se dělí proud vybuzený svazkem elektronů mezi hrot AFM a vzorek mikrokrystalického křemíku.
|
|
|
Diagnostic of semiconductor materials by EBIC method
Davidová, Lenka ; Máca, Josef (referee) ; Čudek, Pavel (advisor)
Master´s thesis is focused on diagnostics of semiconductor materials by EBIC method (measuring of currents induced beam), determination of the lifetime of minority carriers, or their diffusion length. The theoretical part is aimed at the principle of scanning electron microscopy, the characteristic properties of the microscope and the signals generated by the interaction of the primary electron beam with the sample. The thesis describes a structure of semiconducting silicon, band models, types of lattice defects and doped of semiconductor structures. After that it is described the theory of calculation of the diffusion length of minority carriers in semiconductors of type N and P. The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers based on the measured data The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers on the basis of the measured data.
|
|
|
Study of interface graphene-on-silicon by EBIC method
Hammerová, Veronika ; Lišková, Zuzana (referee) ; Mach, Jindřich (advisor)
This bachelor thesis is dedicated to study of interface graphene-on-silicon located on solar cell with graphene layer. The interface was studied by EBIC method and Raman spectroscopy. Solar cells with graphene sheet was fabricated using electron litography, chemical etching and graphene made by CVD method. The thesis describes fabrication of solar cells with graphene layer, method EBIC measured on SEM and analysis of changes graphene-on-silicon interface caused by enlightenment electron beam by Raman spectroscopy. In theorethical part is described p-n junction and Schottky junction of solar cell, graphene and its fabrication, as well as EBIC method fundamentals.
|
|
|
Schottky solar cells with interface graphene/Si modified by gallium
Hlavička, Ivo ; Lišková, Zuzana (referee) ; Mach, Jindřich (advisor)
Main focus of this bachelor thesis is on fabrication, characterization and modification of graphene-on-silicon Schottky solar cells. By transfering CVD graphene onto silicon wafer with electrodes, a basic Schottky junction was created. The junction was then modified by annealing in UHV chamber as well as by gallium deposition. Information about power conversion efficiency of such Schottky solar cells was then obtained by IV measurement. Schottky junction itself was analyzed using X-EBIC method.
|
|
|
Semiconductors structures , charge collection method
Golda, Martin ; Čudek, Pavel (referee) ; Špinka, Jiří (advisor)
This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.
|
|
|
Study of photovoltaic nanostructures using microscopy methods
Hertl, Vít ; Valenta,, Jan (referee) ; Fejfar, Antonín (advisor)
V této diplomové práci je nejprve ve zkratce uvedena teorie fyziky solárních článků, kde jsou zmíněny klíčové procesy ovlivňující účinnost konverze slunečního záření na elektrickou energii. Dále je předložena rešerše o fotovoltaických nanostrukturách (nanodráty, nanokrystaly), jejichž implementací je možné účinnost solárních článků zvýšit. V přehledu experimentálních technik ke zkoumání fotovoltaických nanostruktur je důraz kladen zejména na korelativní měření pomocí SEM a AFM, vodivostního AFM, měření EBIC a mikroskopické měření elektroluminiscence. V experimentální části jsou předloženy výsledky měření struktur mikrokrystalického křemíku, vzorku hetero-přechodového Si solárního článku s kontakty na zadní straně (IBC-SHJ z projektu NextBase) a V-pitů vzorku InGaN/GaN kvantových jam. Měření elektroluminiscence bylo provedeno na vzorcích III-V polovodičů (InGaP, GaAs). Byly vypočítány jinak těžko dostupné charakteristiky III-V tandemových solárních článků pomocí elektroluminiscence a srovnání vlastností IBC-SHJ zjištěných pomocí mikroskopického měření elektroluminiscence a EBIC. Provedením experimentů bylo zjištěno, jakým způsobem se dělí proud vybuzený svazkem elektronů mezi hrot AFM a vzorek mikrokrystalického křemíku.
|
|
|
Advanced Structural Analysis Of Silicon Solar Cells
Papež, Nikola
The study investigates the structural imperfections of photovoltaic cells based on polycrystalline silicon. Experimental characterization focuses in particular on the degradation and defects analysis. Two modern techniques were used – scanning electron microscopy (SEM) with electron beam induced current (EBIC) and 3D digital optical microscopy. The properties and range of cell defects that can significantly affect its function were characterized with this inspection and failure Analysis.
|
|
|
Diagnostic of semiconductor materials by EBIC method
Davidová, Lenka ; Máca, Josef (referee) ; Čudek, Pavel (advisor)
Master´s thesis is focused on diagnostics of semiconductor materials by EBIC method (measuring of currents induced beam), determination of the lifetime of minority carriers, or their diffusion length. The theoretical part is aimed at the principle of scanning electron microscopy, the characteristic properties of the microscope and the signals generated by the interaction of the primary electron beam with the sample. The thesis describes a structure of semiconducting silicon, band models, types of lattice defects and doped of semiconductor structures. After that it is described the theory of calculation of the diffusion length of minority carriers in semiconductors of type N and P. The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers based on the measured data The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers on the basis of the measured data.
|
|
|
Semiconductors structures , charge collection method
Golda, Martin ; Čudek, Pavel (referee) ; Špinka, Jiří (advisor)
This thesis treats about semiconducting silicon structures. It describes the characteristics of the element and creation of P and N type of semiconductor and discusses about different types of faults in the crystal lattice. It deals with the description of methods for monitoring faults in semiconductor ie. determining the properties of semiconductors via EBIC, EBIV and CC methods, which are used for analysis of semiconductor devices and materials. Determining the properties of silicon components is being done by generation of charge carriers in the sample loaded in chamber of the scanning electron microscope by high energy electrons. Bellow the sample surface is being generated an electric charge which is being collected by probes. Using this data obtained by EBIC and CC were evaluated diffusion length and lifetime of electrons.
|
|
|
Schottky solar cells with interface graphene/Si modified by gallium
Hlavička, Ivo ; Lišková, Zuzana (referee) ; Mach, Jindřich (advisor)
Main focus of this bachelor thesis is on fabrication, characterization and modification of graphene-on-silicon Schottky solar cells. By transfering CVD graphene onto silicon wafer with electrodes, a basic Schottky junction was created. The junction was then modified by annealing in UHV chamber as well as by gallium deposition. Information about power conversion efficiency of such Schottky solar cells was then obtained by IV measurement. Schottky junction itself was analyzed using X-EBIC method.
|
guest ::
