Reactive Diffusion of Thin Si Deposits into Ni (111)

2012 ◽  
Vol 323-325 ◽  
pp. 421-426
Author(s):  
B. Lalmi ◽  
C. Girardeaux ◽  
Alain Portavoce ◽  
Bernard Aufray ◽  
Jean Bernardini
Keyword(s):  
Electron Spectroscopy ◽  
Room Temperature ◽  
Reactive Diffusion ◽  
Isothermal Kinetics ◽  
Low Energy Electron Diffraction ◽  
Scanning Tunnelling ◽  
Tunnelling Microscopy ◽  
Low Energy Electron ◽  
Stm Images ◽  
Dimensional Surface

Low energy electron diffraction (LEED), Auger electron spectroscopy (AES) and scanning tunnelling microscopy (STM) were used to study the reactive diffusion of one monolayer of silicon deposited at room temperature onto a Ni (111) substrate. We have done isochronal and isothermal kinetics by AES, and we observed in both cases a kinetics blockage on a plateau corresponding to around one third of a silicon monolayer. STM images and LEED patterns both recorded at room temperature just after annealing, reveal formation of an ordered hexagonal superstructure corresponding probably to a two-dimensional surface silicide.

The Ten-Fold Surface of The Decagonal Al72Ni11Co17 Quasicrystal Studied by Leed, Spa-Leed, Aes and Stm.

2000 ◽  
Vol 643 ◽  
Author(s):  
Erik J. Cox ◽  
Julian Ledieu ◽  
RÓn'n Mcgrath ◽  
Renee D. Diehl ◽  
Cynthia J. Jenks ◽  
...  
Keyword(s):  
Annealing Time ◽  
Electron Spectroscopy ◽  
Annealing Temperature ◽  
Profile Analysis ◽  
Low Energy Electron Diffraction ◽  
Annealing Temperatures ◽  
Scanning Tunnelling ◽  
Tunnelling Microscopy ◽  
Low Energy Electron ◽  
Stm Images

AbstractThe ten-fold surface of the decagonal Al72Ni11Co17 (d-Al-Ni-Co) quasicrystal has been investigated using low energy electron diffraction (LEED), spot profile analysis LEED (SPA- LEED), Auger electron spectroscopy (AES) and scanning tunnelling microscopy (STM). This was done as a function of both annealing temperature and annealing time. The long-range order of the surface, as indicated by LEED, increases both as a function of annealing time and temperature. STM shows the surface to be rough and cluster-like at low annealing temperatures (≤725 K), whilst annealing to temperatures in excess of 725 K results in the formation of terraces. These terraces are small (≤ 100 Å width) at lower annealing temperatures and increase in size (100 Å ≤ x ≤ 500 Å) as the annealing temperature is increased (≥ 850 K). They are characterised by the presence of three-fold protrusions which align preferentially. STM images show single height steps as expected due to the periodicity of d-Al-Ni-Co in the z direction. To date it has not been possible to obtain atomic resolution, although this work is continuing.

Surface Structures of Phosphorus and Indium on Si(111)

1998 ◽  
Vol 05 (01) ◽  
pp. 69-76
Author(s):  
F. P. Netzer ◽  
L. Vitali ◽  
J. Kraft ◽  
M. G. Ramesy
Keyword(s):  
Elevated Temperature ◽  
Room Temperature ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Low Energy Electron Diffraction ◽  
Diffusion Limited ◽  
Lower Terrace ◽  
Surface Reconstructions ◽  
Low Energy Electron ◽  
Stm Images

The interaction of vapor phase P2 with the [Formula: see text] monolayer surface at room temperature and elevated temperature has been monitored by scanning tunneling microscopy (STM) and spectroscopy (STS) in conjunction with Auger electron spectroscopy and low-energy electron diffraction (LEED). The surface rection can be readily followed by STM because of the very different contrast of the reacted areas in the STM images. The reaction develops around overlayer defects at room temperature and appears to be diffusion-limited, whereas at 300°C the reaction is initiated at the step edges, from which the reaction front progresses onto the lower terrace areas. At elevated temperature several ordered surface reconstructions, showing different STS fingerprints, are detected on the P–In/Si(111) surfaces, which are associated tentatively with P- and Si-terminated structures and an ordered InP phase.

The growth of AuGa2 thin films on GaAs(001) to form chemically unreactive interfaces

1986 ◽  
Vol 1 (4) ◽  
pp. 537-542 ◽  
Author(s):  
Jeffrey R. Lince ◽  
Tsai C. Thomas ◽  
Williams R. Stanley
Keyword(s):  
Electron Spectroscopy ◽  
Auger Electron ◽  
Room Temperature ◽  
Substrate Surface ◽  
Film Deposition ◽  
X Ray ◽  
Low Energy Electron Diffraction ◽  
Interface Roughening ◽  
Low Energy Electron ◽  
Electron Energy Loss

Thin AuGa2 films were grown by codeposition from separate Au and Ga evaporation sources on clean GaAs(001) substrates in ultrahigh vacuum, and were studied by Auger electron spectroscopy, electron energy-loss spectroscopy, low-energy electron diffraction, scanning electron microscopy, and x-ray diffractometry. The morphology and crystallinity of the AuGa2 were highly dependent upon the film deposition and annealing history. Films grown on room-temperature substrates were continuous, specular, and polycrystalline, but the dominant orientation was with the (001) planes of the crystallites parallel to the substrate surface. Annealing to temperatures between 300°and 480°C caused the film to break up and coalesce into rectangular crystallites, which were all oriented with (001) parallel to the surface. An anneal to 500°C, which is above the AuGa2 melting point, resulted in the formation of irregular polycrystalline islands of AuGa2 on the GaAs(001) substrate. No interface roughening or chemical reactions between the film and substrate or interface were observed for even the highest-temperature anneals.

Growth of thin Pb Layers on Cu(001)

1984 ◽  
Vol 41 ◽  
Author(s):  
R. J. Culbertson ◽  
Y. Kuk ◽  
L. C. Feldman
Keyword(s):  
Electron Spectroscopy ◽  
Auger Electron ◽  
Room Temperature ◽  
Three Dimensional ◽  
High Energy ◽  
Two Dimensional ◽  
Ion Scattering ◽  
Island Growth ◽  
Low Energy Electron Diffraction ◽  
Low Energy Electron

AbstractThe growth of thin Pb layers (<12 monolayers) was studied in ultrahigh vacuum by high energy ion scattering/channeling, low energy electron diffraction (LEED)), and Auger electron spectroscopy (AES). Deposition and analysis were performed at 300 K and 140 K. The Pb coverage was determined quantitatively by ion scattering. The results indicated a clear transition in the growth mode as a function of temperature. At 300 K, two-dimensional island growth was observed up to 1.0 monolayer, followed by three-dimensional epitaxial growth of strained islands. Two-dimensional island growth was observed up to 5 monolayers at 140 K. The relative positions of the overlayer atoms relative to the substrate was studied to understand two-dimensional phase transitions above room temperature.

EFFECT OF Cu DEPOSITION AND ANNEALING UPON A GaSe/Si(111) HETEROJUNCTION

1999 ◽  
Vol 06 (06) ◽  
pp. 1173-1178 ◽  
Author(s):  
B. ABIDRI ◽  
J.-P. LACHARME ◽  
M. GHAMNIA ◽  
C. A. SÉBENNE ◽  
M. EDDRIEF ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Low Energy ◽  
Layered Semiconductor ◽  
Low Energy Electron Diffraction ◽  
Low Energy Electron ◽  
Temperature Interaction

Single crystal substrates of GaSe, a layered semiconductor with a 2 eV band gap, were epitaxially grown by MBE onto a Si(111)(1×1)–H substrate, forming a perfectly abrupt heterojunction. Controlled amounts of Cu were sequentially deposited onto the clean passive surface of GaSe from a few tenths to several hundred monolayers (1 ML refers to the GaSe surface: 8 × 1014 at/cm 2). After given Cu depositions, the effect of UHV annealings at increasing temperatures was studied, until GaSe removal. The system was characterized as a function of either Cu deposit or annealing temperature using low energy electron diffraction, Auger electron spectroscopy and photoemission yield spectroscopy. The room temperature interaction starts as an apparent intercalation process until Cu islands begin to form, beyond about 50 ML. Upon annealings as low as 250°C, several ML of Cu disappear into the bulk of an apparently recovered GaSe, towards the GaSe/Si interface.

ADSORPTION AND REACTION OF NITRIC OXIDE ON Si(111)-Au SURFACES

2006 ◽  
Vol 13 (02n03) ◽  
pp. 191-196 ◽  
Author(s):  
T. NISHIMURA ◽  
K. HATTORI ◽  
K. KATAOKA ◽  
Y. SHIMAMOTO ◽  
H. DAIMON
Keyword(s):  
Nitric Oxide ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Room Temperature ◽  
Low Energy ◽  
The Other ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Low Energy Electron Diffraction ◽  
Low Energy Electron

We studied adsorption and reaction of nitric oxide on Si (111)7 × 7, 5 × 2- Au , [Formula: see text], [Formula: see text], and 6 × 6- Au surfaces with low-energy electron diffraction, Auger electron spectroscopy, and scanning tunneling microscopy (STM). We found that NO gas reacts most strongly with the 7 × 7 surface, strongly with the 5 × 2- Au surface, and little with the other Si (111)- Au surfaces. STM results indicated that the NO exposure removes adatoms and erodes the row structure on the 5 × 2- Au surface at room temperature.

LEED and AES studies of chemisorption resulting from low exposures of C2H4, CO, and PH3 to the (0001) surface of zirconium

1988 ◽  
Vol 66 (12) ◽  
pp. 3157-3161 ◽  
Author(s):  
J. R. Lou ◽  
P. C. Wong ◽  
K. A. R. Mitchell
Keyword(s):  
Electron Spectroscopy ◽  
Room Temperature ◽  
Bulk Diffusion ◽  
Surface Region ◽  
Hydrogen Desorption ◽  
Low Energy Electron Diffraction ◽  
Surface Ordering ◽  
Low Energy Electron ◽  
The One ◽  
First Time

Low-energy electron diffraction (LEED) and Auger electron spectroscopy (AES) have been used to study for the first time the chemisorption systems formed on the (0001) surface of zirconium by exposing to C2H4, CO, and PH3 in the one to ten Langmuir regime. The adsorptions are done at room temperature, but there is subsequent heating to optimize the surface ordering. The main observations are as follows: (i) after heating C2H4-covered surfaces to effect hydrogen desorption, the remaining carbon can form two different ordered (1 × 1)-C structures; (ii) CO forms both (2 × 2)- and (1 × 1)-type structures; (iii) the temperature at which the bulk diffusion of oxygen becomes significant, as determined by AES, is about 40 °C greater on a CO-treated surface than for an O2-treated Zr(0001) surface; and (iv) heating a PH3-covered surface can yield a weakly-ordered (3 × 3)-P structure. The observation (iv) contrasts with that for the analogous surface prepared previously with H2S; the poorly developed (3 × 3)-P surface structure results from the fact that the temperatures required for surface ordering overlap with those which yield a loss of phosphorus from the surface region.

Sign in / Sign up

Export Citation Format

Share Document