Formation of Nanocrystalline Germanium via Oxidation of Si₀.₅₄Ge₀.₄₆ for Memory Device Applications

Abstract

In this work, we studied the possibility of synthesizing nanocrystalline germanium (Ge) via dry and wet oxidation of both amorphous and polycrystalline Si₀.₅₄Ge₀.₄₆ films. In dry oxidation, Ge was rejected from the growing SiO₂ forming a Ge-rich polycrystalline layer. As for wet oxidation, Ge was incorporated into the oxide, forming a layer of mixed oxide, SixGe₁₋xOy. Formation of nanocrystalline Ge was observed when the layer of SixGe₁₋xOy was annealed in a N₂ ambient. We have fabricated a metal-insulator-semiconductor structure with nanocrystalline Ge embedded within the insulator layer to study its feasibility as a memory device.