Search for dissertations about: "buffer"

Showing result 6 - 10 of 477 swedish dissertations containing the word buffer.

  2. 6. Sputtering of Precursors for Cu2ZnSnS4 Solar Cells and Application of Cadmium Free Buffer Layers

    Author : Tove Ericson; Charlotte Platzer-Björkman; Tomas Kubart; Marika Edoff; Yaroslav Romanyuk; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; solar cells; thin film; buffer layer; sputtering; reactive sputtering; CZTS; kesterite; zinc tin oxide; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Abstract : The aim of this thesis is to understand the influence of the deposition process and resulting film properties on Cu2ZnSnS4 (CZTS) thin film solar cells. Two main aspects are studied, namely formation of absorber precursors by sputtering, and alternative Cd-free buffer materials with improved band alignment. READ MORE

  4. 7. ALD Buffer Layer Growth and Interface Formation on Cu(In,Ga)Se2 Solar Cell Absorbers

    Author : Jan Sterner; Lars Stolt; Roland Scheer; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; thin film; Cu In; Ga Se2; CIGS; chalcopyrite; ALD; sulfurization; buffer layer; XPS; UPS; electron spectroscopy; band alignment; atomic layer deposition; Elektronik; Electronics; Elektronik;

    Abstract : Cu(In,Ga)Se2 (CIGS) thin film solar cells contain a thin layer of CdS. To avoid toxic heavy-metal-containing waste in the module production the development of a cadmium-free buffer layer is desirable. This thesis considers alternative Cd-free buffer materials deposited by Atomic Layer Deposition (ALD). READ MORE

  5. 8. Cadmium Free Buffer Layers and the Influence of their Material Properties on the Performance of Cu(In,Ga)Se2 Solar Cells

    Author : Adam Hultqvist; Charlotte Platzer-Björkman; Tobias Törndahl; Marika Edoff; Takashi Minemoto; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Cu In; Ga Se2; Solar cells; Thin film; Buffer layer; Window layer; ZnO; Zn O; S ; Zn; Mg O; Zn-Sn-O; Semiconductor physics; Halvledarfysik; Engineering Science with specialization in Solid State Physics; Teknisk fysik med inriktning mot fasta tillståndets fysik;

    Abstract : CdS is conventionally used as a buffer layer in Cu(In,Ga)Se2, CIGS, solar cells. The aim of this thesis is to substitute CdS with cadmium-free, more transparent and environmentally benign alternative buffer layers and to analyze how the material properties of alternative layers affect the solar cell performance. READ MORE

  6. 9. Modelling Band Gap Gradients and Cd-free Buffer Layers in Cu(In,Ga)Se2 Solar Cells

    Author : Jonas Pettersson; Charlotte Platzer-Björkman; Marika Edoff; Marc Burgelman; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; CIGS; Thin film solar cells; Electrical modelling; Alternative buffer layers; Gallium gradients; Simulations; Electrical characterization; Metastabilities; Light-soaking; Hall measurements; Persistent photoconductivity; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Abstract : A deeper understanding of Cu(In,Ga)Se2 (CIGS) solar cells is important for the further improvement of these devices. This thesis is focused on the use of electrical modelling as a tool for pursuing this aim. Finished devices and individual layers are characterized and the acquired data are used as input in the simulations. READ MORE

  7. 10. Minimal volume ventilation in lung injury : With special reference to apnea and buffer treatment

    Author : Staffan Höstman; Anders Larsson; Hans Hjelmqvist; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; VILI; THAM; buffers; apneic oxygenation; respiratory acidosis; hypercapnia; low volume ventilation; mechanical ventilation; ultra-protective ventilation; Anestesiologi och intensivvård; Anaesthesiology and Intensive Care;

    Abstract : A fairly large portion of patients receiving surgical or intensive care will need mechanical ventilation at some point. The potential ventilator-induced lung injury (VILI) is thus of interest. One of the main causal factors in VILI is the cyclic energy shifts, i.e. READ MORE