LabAdviser/314/Microscopy 314-307/SEM/Nova/Transmission Kikuchi diffraction: Difference between revisions
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Therefore it has been necessary to find another reliable evaluation criterion to confirm the exact starting temperature of formation of the holes in the film. The new criterion used consisted in the evaluation of the quality of the Kikuchi patterns on the non-indexed areas of the map. Fig. 11a shows the IPFZ map acquired at 210°C: in this map there are several non-mapped (and therefore black) areas. Fig. 11b shows the Kikuchi pattern recorded from a dewetted area of the sample, while Fig. 11c shows the pattern from an area with very fine grains (in the range of 10-20 nm). The difference between those two patterns is evident. In c) the Kikuchi pattern is visible, but indexing was difficult due to the chosen step size and to the fact that the grain size was close to the physical resolution of the TKD technique; thus many patterns originated from grain boundaries were difficult to be indexed. In b) no pattern is instead visible, indicating lack of crystalline material, i.e. only the Si3N4 substrate was present at that position. | Therefore it has been necessary to find another reliable evaluation criterion to confirm the exact starting temperature of formation of the holes in the film. The new criterion used consisted in the evaluation of the quality of the Kikuchi patterns on the non-indexed areas of the map. Fig. 11a shows the IPFZ map acquired at 210°C: in this map there are several non-mapped (and therefore black) areas. Fig. 11b shows the Kikuchi pattern recorded from a dewetted area of the sample, while Fig. 11c shows the pattern from an area with very fine grains (in the range of 10-20 nm). The difference between those two patterns is evident. In c) the Kikuchi pattern is visible, but indexing was difficult due to the chosen step size and to the fact that the grain size was close to the physical resolution of the TKD technique; thus many patterns originated from grain boundaries were difficult to be indexed. In b) no pattern is instead visible, indicating lack of crystalline material, i.e. only the Si3N4 substrate was present at that position. | ||
[[File:Picture66.png| | [[File:Picture66.png|500px|center|thumb|Fig. 11: a) IPFZ map of the growth direction of the 15 nm Au thin film at 210°C; b) signal from a dewetted area of the sample revealing no pattern and c) non-indexed pattern from a fine grain region.]] | ||