HIGH QUALITY p -FeSiz THIN FILMS FORMED BY MBE FOR INNOVATIVE SOLAR CELLS

In order to explore the possibility of iron-disilicide (P-FeSi,) material for low cost and high conversion efficiency solar cells, high quality P-FeSi2 thin films have been formed by molecular beam epitaxy (MBE) technique with silicon (Si) wafers as the substrates. The surface morphology, the crystal structure, the depth profile of element constitution and the optical and electrical properties of the films were systematically evaluated by using SEM, TEM, XRD, RBS, SIMS, optical transmission and Hall effect measurements, respectively. A high quality thin template layer was found essential for epitaxial growth of single crystal P-FeSi2 and for preventing the interdiffusion of Si and Fe at the filmisubstrate interface. A P-PeSi, film was also successfully formed on CaFl for the first time, suggesting the multiple choices of substrates. Manufactured devices showed that P-FeSi, is practically a promising semiconductor for making solar cells.