FIB-Nanolab with low temperature cathodoluminescence expansion

点击翻译按钮获取中文摘要

For the precise and minimally invasive target preparation on nanometer scale, a focused ion beam (FIB) system equipped with low temperature cathodoluminescence (FIB-Nanolab) is applied. Beside probing structural properties via field emission electron gun of the dual beam FIB, regions intended for preparation are selected by the emission characteristics of semiconducting samples using cathodoluminescence (CL) spectroscopy. This enables a precise preparation regarding chosen physical properties (like spectral fingerprints) on nm scale; among others the use of the luminescence characteristics of quantum dots, quantum wires, quantum wells or optically active crystal defects. The FIB-nanolab configuration enables a three dimensional CL tomography due to the material removal using FIB and subsequent in-situ CL analysis in sequential series with detailed depth profiles. The analysis of the complete three dimensional potential landscape of the charge carriers in ternary or quaternary semiconductors (e.g. investigation of segregation effects) and in quantum layer stacks is feasible.The planned specifications of the FIB-nanolab allows the precise structuring of innovative functional semiconductors on nanometer scale (nanoprototyping). Here, the altered photonic properties of a microcavity or photonic crystal are intended to control and possibly corrected during the prototyping by low temperature CL spectroscopy.The direct selection of individual semiconductor quantum structures with suitable spectral properties before and during the FIB process is a unique possibility. It enables the fabrication of deterministic single photon emitters via targeted spectral selection of single resonant quantum dots by LHe CL and following ion milling of micro rod resonators via FIB. Beyond, electron/ion beam induced metal deposition on nm scale enables an electrical contacting of the quantum optoelectronic devices. Even plasmonic properties are assumed to modulate spatially by FIB-induced metal deposition.At the same time, a reduced ion irradiation damage is assumed for FIB processing at liquid Helium temperatures (LHe). Thus, the CL system with sample cooling is used as selection process as well as reduction of irradiation damage.The FIB-nanolab will be a worldwide unique tool and an essential upgrading for the Otto-von-Guericke-University Magdeburg as an center for semiconductor nanophotonics.