Nickel-assisted metal-induced crystallization of silicon: Effect of native silicon oxide layer
Autor: | Rodrigo Martins, Luís Pereira, N. Schell, Elvira Fortunato, Rui M. S. Martins |
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Rok vydání: | 2006 |
Předmět: |
Amorphous silicon
Materials science Silicon Metals and Alloys Analytical chemistry Oxide chemistry.chemical_element Mineralogy Surfaces and Interfaces Chemical vapor deposition Surfaces Coatings and Films Electronic Optical and Magnetic Materials law.invention Nickel chemistry.chemical_compound chemistry law Materials Chemistry Crystallization Silicon oxide Metal-induced crystallization |
Zdroj: | Thin Solid Films. :275-279 |
ISSN: | 0040-6090 |
Popis: | This work focuses on the role of the native oxide layer (SiO2) on the nickel (Ni)-assisted crystallization of amorphous silicon (a-Si). In some samples, the native oxide was removed using a HF-diluted solution before Ni layers with 0.5 nm be deposited on a-Si. The results show that the presence of a thin SiO2 layer of about 3 nm between the a-Si and the Ni delays the crystallization process. Ellipsometry data show that, after annealing for 5 h at 500 °C, the HF-cleaned sample presents a crystalline fraction of 88%, while the one with the native oxide has only 35%. This difference disappears after 20 h where both samples present similar crystalline fraction. These facts are also reflected on the film's electrical properties, where the activation energy for samples annealed for 5 h rises from 0.42 eV to 0.55 eV, when the oxide layer is removed. After 20 h and 30 h, the activation energy is around 0.55 eV for both kinds of samples, meaning that films with similar electrical properties are now obtained. However, the XRD data suggest the presence of some structural differences attributed to slight differences on the crystallization process. |
Databáze: | OpenAIRE |
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