| Popis: |
Materials consisting of semiconductor core-shell nanostructures, like nanowires or quantum dots attract special attention due to their highly adjustable electronic structure and optical properties. Especially interesting for the application of such materials in solar cells is the fact that Ge/Si cor/shell quantum dots(QD) have a type II band alignment, leading to the separation of charge carriers [1, 2]. We have recently developed a method for the growth of self-assembled core/shell Ge/Si QDs in an amorphous alumina matrix [3, 4], but it can also be done in SiC and Si3N4 matrices. Depending on the matrix type, different deposition conditions are needed for the quantum dots to form. Furthermore, the matrix type greatly influences the transport properties. Different matrices produce different transport barriers between the QDs, with tunneling probability heavily dependent on the height of the barrier. Here were port the influence of the deposition conditions on the QD formation in all matrices, as well as the effect of the matrix type on the electrical properties. |
