The objective of this project is to do a thorough fundamental feasibility study about the inherent possibilities of FeSi2 as a photovoltaic material.The main goal is the preparation of epitaxial and non-epitaxial thin films of ß-FeSi2 and the study of their basic structural, optical and electrical properties.
This project finally aims at the preparation of polycrystalline thin film solar cells on Si-substrates and on cheap substrate materials like glass or ceramics. By means of electrical, microstructural and analytical characterization of the films it has to be clarified whether the high defect density, found until now, is an intrinsic (crystal defects) or extrinsic (impurities) effect. The thin film quality has to be increased by an optimization of the Si/Fe ratio, the preparation parameters and the right choice of an optimal substrate material. If these examinations will be successful a next subject is the preparation and characterization of metal-beta-FeSi2 and ZnO-beta-FeSi2 interfaces to get a built-in electrostatic field acting as a barrier for the majority carriers. Other structures to be investigated are heterojunctions with Si and regular p-n junctions.
The work is organized in 3 main work packages: WPl: Formation of the FeSi2-layers (epitaxial or non-epitaxial growth of beta-FeSi2 thin films on Si wafers; polycrystal growth of beta-FeSi2 thin films on non silicon substrates such as glass WP2: Formation of homo- and heterojunctions with FeSi2 (devices ranging
homojunctions). WP3: Structural, compositional, electrical, optical,...characterization
Funding SchemeCSC - Cost-sharing contracts