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1

Band structure of In chains on Si(335)-Au

Skrobas K., Zdyb R., Kisiel M., Jałochowski M.

Materials Science Poland

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2008

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Vol. 26, No. 1

55--61

EN

The crystallographic and electronic band structure of In induced reconstruction of Si(335)-Au surface have been studied with reflection high electron energy diffraction and angle resolved photoemission spectroscopy in ultrahigh vacuum conditions. The photoemission spectra recorded along chains show strongly dispersive band crossing the Fermi level while dispersionless spectra are found in the perpendicular direction. Diffraction experiments support one-dimensional character of the structures. A simple model of In reconstructed Si(335)-Au surface has been put forward.

2

Band structure of Au monoatomic chains on Si(335) and Si(557) surfaces

Kisiel M., Skrobas K., Zdyb R., Jałochowski M.

Optica Applicata

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2005

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Vol. 35, nr 3

449-455

EN

The electronic band structure of the Si(557) and Si(335) surfaces covered with monoatomic Au chains produced in UHV conditions, is investigated in detail by angle-resolved photoelectron spectroscopy (ARPES), especially for the surface state bands near the Fermi energy. The ARPES spectra in the plane parallel to step edges for Si(557)-Au vicinal surface show strongly dispersive electron energy bands, characteristic of one-dimensional structure. The band dispersion is also calculated within tight-binding model, with two adjustable coupling parameters t{ and t2, for the first and second neighbors along the chains, respectively, and compared with that determined from the photoemission experiment. The scanning tunneling microscopy (STM) imaging and reflection high energy electron diffraction (RHEED) studies enabled us to determine atomic chain separation and its internal structure. The study shows that the structural anisotropy of these surfaces induces highly anisotropic electronic structure.

3

Ordering of the vicinal Si(15 1 0) surface at low Au coverage

Mazurek P., Jałochowski M.

Optica Applicata

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2002

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Vol. 32, nr 3

247-252

EN

Reflection high-energy electron diffraction (RHEED) and scanning tunnelling microscopy (STM) are used to investigate the ordering process of vicinal silicon surface. A vicinal Si(15 1 0) sample was cut from a Si(001) monocrystal and oriented by X-ray diffractometry techniques. At Au coverage within 1–2 ML and after the subsequent annealing at about 1000 K in UHV conditions this surface exhibits a rectangular imbricate step/terrace structure. The best surface ordering was found at 1.5–2 ML Au coverage where flat Si(001) terraces show 5×3.2 surface reconstruction. The edges of these rectangular terraces are parallel to the [011] and [011] direction. Due to high density of corners formed by the rectangular terraces, this surface may be suitable for nucleation of quasi zero-dimensional structures.

4

Optical anisotropy of Pb nanowires on Si(533) surface

Jałochowski M., Stróżak M.

Optica Applicata

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2002

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Vol. 32, nr 3

373-379

EN

Ultrathin Pb films on Si(533)/Au surface deposited at low temperatures are investigated by STM, RHEED, and by optical reflectance difference spectroscopy (RDS). In particular, we report the observation by RDS of an anisotropy in the optical reflectance of the Si(533) surface covered by Pb nanowires. It is found that the optical anisotropy originates from anisotropy of electrical conductivity of the Si(533) substrate and the anisotropy of Pb nanowires formed on this surface

5

Mesoscopic Pb wires on ordered vicinal Si(111)

Jałochowski M.

Electron Technology

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2000

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Vol. 33, No. 3

375-379

EN

Growth of Pb mesoscopic wires on ordered vicinal Si(111) surface covered with sub-monolayer amount of Au has been studied by RHEED and LEEM. For a sample misoriented by 14,42° from the (111) plane towards [211] azimuthal direction at a coverage equal to 0.28 ML of Au, the RHEED pattern showed a regular distribution of monoatomic steps. At room temperatures and 280 K spontaneous self-organization of mesoscopic Pb wires on these substrates was observed. Three-dimensional elongated islands were first observed after deposition of one Pb monolayer. With further Pg deposition these elongated islands grew into set of perfectly parallel wedge-shaped wires. The wires were approximately 90 nm wide, up to several žm long and were aligened parallel to substrate steps. The density of wires was sttrongly corelated with perfction of Si(533) surfaces. A model of the wire is presented.

6

Growth of the ultra-thin Pb layers on Si(533) surface

Zdyb R., Stróżak M., Jałochowski M.

Electron Technology

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2000

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Vol. 33, No. 3

380-384

EN

Vicinal Si(111) surfaces were investigated by Reflection High Energy Electron Diffraction (RHEED). The samples were cut 14.42° off the (111) plane in (112) direction. The Si(533) plane with a regularly distributed terraces and monoatonic steps was obtained by depositing of 0.28 monolayer (ML) of Au on a clea vicinal surface and annealing it up to 900 K. The length of the terraces and the height of the steps were determined equal to 12.27 Å and 3.22 Å , respectively. The structure of metallic Pb layers deposited on the vicinal suraces was studied. Up to the thickness equal to 4ML we observed the growth of Pb in from of one-and two-dimensional structures. Above this thickness only two-dimensional crystallites exist. The mean sizes of the Pb crystallities were determined from the intensity distribution of the diffraction spots.

7

Transmission of low-energy electrons through Pb quantum well

Zdyb R., Stróżak M., Jałochowski M.

Electron Technology

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1998

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Vol. 31, No. 3/4

315-319

EN

The Pb film have been grown on Si(111)-(6x6)Au substrate. Electron transmission through the film was measured as a function of incident electron energy. Two types of structures were observed in collected current. One of them strongly depends on the thicknees of Pb layers, characteristic of the quantum size effect. The other is associated with the bulk band structure of Pb. The value of inner potential of Pb equal to 14 eV was determined.

8

Optical reflectivity of ultrathin Pb layers and the quantum size effect

Jałochowski M., Stróżak M., Zdyb R.

Electron Technology

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1998

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Vol. 31, No. 3/4

291-300

EN

We have studied in situ the reflectance difference (RD) during depositon of ultrathin Pb epitaxial film onto Si(111)-(6x6)Au substrates held at 100 K in UHV conditions. S- and p-polarized radiation with energy within the range from 0.5 eV to 3.0 eV was used to excite electron transitions in the Pb samples showing the quantum size effects (QSE). The optical reflection data were analysed using classical and QSE theories. Observed thicknees-dependet reflectivity variations were correlated with previously measurmed electrical resistivity oscillations. Scattering time of electrons involved in the electrical resistivity measurements. Evidences of optical diamagnetic and paramagnetic response of electrons in the metallic quantum well are prasented and discussed.

9

Apparatus for the measurement of critical temperature in metallic quantum wells

Orłowski M., Paprocki K., Korczak Z., Jałochowski M.

Electron Technology

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1998

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Vol. 31, No. 3/4

516-519

EN

The apper describes construction of UHV apparatus and the method of critical temperature measurement of thin Pb layers. Electronic setup for specific resistivity measurement Pb layers during thier deposition on Si(111) substrate is presented. The results obtained during specific resistivity measurements of Pb layers at temperatures above Tc illustrates the accuracy of proposed measuremement method.