title: FIB Plan View Preparation and Electron Tomography of Ga-Containing Droplets Induced by Melt-Back Etching in Si.
abstract: Melt-back etching is an effect that can occur for gallium (Ga) containing III/V semiconductors grown on Si. Since this effect influences interfaces between the two compounds and therefore the physical characteristics of the material composition, it is desirable to understand its driving forces. Therefore, we investigated Ga grown on Si (001) via metal organic chemical vapor deposition using trimethyl Ga as a precursor. As a result of the melt-back etching, Ga-containing droplets formed on the Si surface which reach into the Si wafer. The shape of these structures was analyzed by plan view investigation and cross sectional tomography in a (scanning) transmission electron microscope. For plan view preparation a focused ion beam was used to avoid damage to the Ga-containing structures, which are sensitive to the chemicals normally used during conventional plan view preparation. Combining the results of both investigation methods confirms that the Ga-containing structure within the Si exhibits a pyramid shape with facets along the Si {111} lattice planes.
authors.affiliation: Faculty of Physics and Materials Science Center,Philipps-Universität Marburg,Hans-Meerwein-Straße 6,35032 Marburg,Germany.
authors.forename: Katharina I
authors.initials: KI
authors.lastname: Gries
authors.affiliation: Faculty of Physics and Materials Science Center,Philipps-Universität Marburg,Hans-Meerwein-Straße 6,35032 Marburg,Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Werner
authors.affiliation: Faculty of Physics and Materials Science Center,Philipps-Universität Marburg,Hans-Meerwein-Straße 6,35032 Marburg,Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Beyer
authors.affiliation: Faculty of Physics and Materials Science Center,Philipps-Universität Marburg,Hans-Meerwein-Straße 6,35032 Marburg,Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Stolz
authors.affiliation: Faculty of Physics and Materials Science Center,Philipps-Universität Marburg,Hans-Meerwein-Straße 6,35032 Marburg,Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Volz
keywords: electron tomography; focused ion beam preparation; melt-back etching; metallic gallium; transmission electron microscopy