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Figure 2. LEED pattern configuration of (a) the clean STO(100) surface and (b) the Fe (2.5 ML)/STO(100) surface. (c) A model of the direc atomic lattice of Fe on STO(100) is shown, with the full and the open cycles representing the Fe and the Ti surface atoms, respectively. The dashed square shows the surface lattice unit shell. transition lines increase, while those of the substrate ones decrease analogously. Since the scattering of the data does not allow us to identify any unambiguous breaks (although we cannot rule out their presence and thus a piecewise linear curve), polynomial lines have been drawn to guide the eye. This nonlinear Auger signal variation may be due to either the formation of three-dimensional clusters (VW mode) or to the evolution of successive incomplete layers [24]. The latter growth mode, which is known as simultaneous multilayers (SM mode), is more likely since the attenuations of the substrate signals are too large to be explained by the VW We also performed LEED measurements, which showed that the deposition of Fe on the STO(100) surface caused the gradual disappearance of the | x | substrate symmetry in rather early adsorption stages. However, for coverages 21.5 ML, a new strongly diffuse (1 x 1) LEED pattern appeared. The LEED pattern configurations of the clean and the Fe (2.5 ML)/STO(100) surface are shown in figures 2(a) and (b), respectively. The spots of the Fe (1.5 ML)/STO(100) diffraction pattern were initially very broad but progressively

Figure 2 LEED pattern configuration of (a) the clean STO(100) surface and (b) the Fe (2.5 ML)/STO(100) surface. (c) A model of the direc atomic lattice of Fe on STO(100) is shown, with the full and the open cycles representing the Fe and the Ti surface atoms, respectively. The dashed square shows the surface lattice unit shell. transition lines increase, while those of the substrate ones decrease analogously. Since the scattering of the data does not allow us to identify any unambiguous breaks (although we cannot rule out their presence and thus a piecewise linear curve), polynomial lines have been drawn to guide the eye. This nonlinear Auger signal variation may be due to either the formation of three-dimensional clusters (VW mode) or to the evolution of successive incomplete layers [24]. The latter growth mode, which is known as simultaneous multilayers (SM mode), is more likely since the attenuations of the substrate signals are too large to be explained by the VW We also performed LEED measurements, which showed that the deposition of Fe on the STO(100) surface caused the gradual disappearance of the | x | substrate symmetry in rather early adsorption stages. However, for coverages 21.5 ML, a new strongly diffuse (1 x 1) LEED pattern appeared. The LEED pattern configurations of the clean and the Fe (2.5 ML)/STO(100) surface are shown in figures 2(a) and (b), respectively. The spots of the Fe (1.5 ML)/STO(100) diffraction pattern were initially very broad but progressively

Related Figures (5)

Figure 1. The AP-PHs of Fe (47 eV), Fe (650 eV), O (510 eV), Ti (380 eV) and Sr (110 eV) Auger lines versus Fe doses on the STO(100) surface at RT. The estimated coverage in ML is also shown. Polynomial lines are drawn as guides to the eye.
Figure 1. The AP-PHs of Fe (47 eV), Fe (650 eV), O (510 eV), Ti (380 eV) and Sr (110 eV) Auger lines versus Fe doses on the STO(100) surface at RT. The estimated coverage in ML is also shown. Polynomial lines are drawn as guides to the eye.
Figure 3. The WF change, A®, of the STO(100) surface as a function of Fe doses and coverage at RT.
Figure 3. The WF change, A®, of the STO(100) surface as a function of Fe doses and coverage at RT.
Figure 4. The EELS measurements of the STO(100) surface covered with different amounts of Fe at RT (solid lines) and after annealing at several temperatures (dashed lines). The electron primary energy is E, = 100 eV.
Figure 4. The EELS measurements of the STO(100) surface covered with different amounts of Fe at RT (solid lines) and after annealing at several temperatures (dashed lines). The electron primary energy is E, = 100 eV.
Figure 5. The AP-PHs of Fe (47 eV), Fe (650 eV), O (510 eV) and Ti (380 eV) Auger transition lines as a function of the substrate temperature for 20 s anneals. The annealed surface is the Fe (60 D)/STO(100). Note that the 1 x 1 symmetry remains for annealing up to about 800 K.
Figure 5. The AP-PHs of Fe (47 eV), Fe (650 eV), O (510 eV) and Ti (380 eV) Auger transition lines as a function of the substrate temperature for 20 s anneals. The annealed surface is the Fe (60 D)/STO(100). Note that the 1 x 1 symmetry remains for annealing up to about 800 K.
Figure 6. TDS measurements of Fe (56 amu) for Fe deposition on the STO(100) surface. The disproportion in the temperature axis is due to the flash desorption mode where the desorption spectra have been recorded.
Figure 6. TDS measurements of Fe (56 amu) for Fe deposition on the STO(100) surface. The disproportion in the temperature axis is due to the flash desorption mode where the desorption spectra have been recorded.
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Materials SciencePhysical ChemistryThin Films and CoatingsSurface PhysicsThin film growthThin film (Physics)Nanotechnology
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