Specific Process Knowledge/Thin film deposition/Deposition of Gold/Adhesion layers: Difference between revisions
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For the chemical distribution of the elements in the 2nm Ti/2nm Au sample, the STEM-EDX measurements at the Ti/Au interface showed the presence of a continuous Ti layer below the Au layer (Fig. 8a). The analysis of the 2nm Cr/2nm Au sample showed instead the presence of Cr throughout the whole thickness of the Au layer (Fig. 8b). Since Cr and Au were deposited sequentially and not by a co-deposition process, this result suggests a strong inter-diffusion. The 2nm Cr/20nm Au sample was also investigated, to understand the degree of inter-diffusion for a thicker Au layer (Fig. 8c). In this case the inter-diffusion between the elements was incomplete, being present for a thickness of 2-3 nm. This suggests that the diffusion process is limited to such a thickness when Cr and Au are deposited at room temperature. | For the chemical distribution of the elements in the 2nm Ti/2nm Au sample, the STEM-EDX measurements at the Ti/Au interface showed the presence of a continuous Ti layer below the Au layer (Fig. 8a). The analysis of the 2nm Cr/2nm Au sample showed instead the presence of Cr throughout the whole thickness of the Au layer (Fig. 8b). Since Cr and Au were deposited sequentially and not by a co-deposition process, this result suggests a strong inter-diffusion. The 2nm Cr/20nm Au sample was also investigated, to understand the degree of inter-diffusion for a thicker Au layer (Fig. 8c). In this case the inter-diffusion between the elements was incomplete, being present for a thickness of 2-3 nm. This suggests that the diffusion process is limited to such a thickness when Cr and Au are deposited at room temperature. | ||
[[File:Picture29.png| | [[File:Picture29.png|350px|center|thumb|Fig. 8: STEM-EDX maps of the 2nm Ti/2nm Au sample (a), 2nm Cr/2nm Au sample (b) and 2nm Cr/20nm Au sample (c). The Au L-alpha signal is acquired at 9713 eV, the Ti K-alpha signal at 4510.9 eV and the Cr K-alpha signal at 5414.7 eV.]] | ||
To verify the chemical composition of the samples, in particular to investigate a possible presence of oxygen in the adhesion layer, STEM-EELS analysis was used. A line scan across the layer interfaces of the 2-Ti/2-Au sample shows the presence of a Ti core loss L3 edge at 460 eV and an L2 edge at 465 eV. A SiO2 O-K edge is visible at 538 eV, while the O-K edge of O bounded to Ti is found at 532 eV (Fig. 5.10a). | To verify the chemical composition of the samples, in particular to investigate a possible presence of oxygen in the adhesion layer, STEM-EELS analysis was used. A line scan across the layer interfaces of the 2-Ti/2-Au sample shows the presence of a Ti core loss L3 edge at 460 eV and an L2 edge at 465 eV. A SiO2 O-K edge is visible at 538 eV, while the O-K edge of O bounded to Ti is found at 532 eV (Fig. 5.10a). | ||