Silicon Films with Gallium Rich Nanograins - from Superconductor to Insulator
Silicon Films with Gallium Rich Nanograins - from Superconductor to Insulator
Heera, V.; Fiedler, J.; Hübner, R.; Schmidt, B.; Voelskow, M.; Skorupa, W.; Skrotzki, R.; Herrmannsdörfer, T.; Wosnitza, J.; Helm, M.
Si films sputter deposited on SiO2 substrates are enriched with Ga by ion implantation through a capping SiO2 layer. The morphology and the electrical transport properties of these films are investigated after rapid thermal annealing. Amorphous, Ga rich nanograins are embedded in a nanocrystalline Si matrix. The nanograins are metallic in the normal state and superconducting below 7 K. They form a random network of junctions to heavily doped Si crystallites. Small modifications of the junction properties, e.g. by annealing or current pulses, can dramatically change the electronic transport in the film. Ga rich Si films show a wealth of low-temperature transport phenomena which have been known until now only from granular metals or high temperature superconductors: superconductor-insulator transition, quasi-reentrant superconductivity and current controlled sheet resistance. The possibility to fabricate and tailor films of Ga rich Si with microelectronics compatible technology make it a promising material for the integration of superconducting circuits into Si devices.
Keywords: Silicon-Gallium-Film; Granular Composite; Superconductor-Insulator Transition; Hopping Conduction; Electric Current Effect
Involved research facilities
- High Magnetic Field Laboratory (HLD)
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 18497) publication
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New Journal of Physics 15(2013), 083022
DOI: 10.1088/1367-2630/15/8/083022
Cited 15 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-18497