The Morphology of Cu Clusters on SrTiO3(001) at Initial Stages of Metal Film Growth

1994 ◽  
Vol 357 ◽  
Author(s):  
Y. Liang ◽  
D. L. Carroll ◽  
D. A. Bonnell
Keyword(s):  
Vapor Deposition ◽  
Metal Film ◽  
Elevated Temperatures ◽  
Film Growth ◽  
Three Dimensional ◽  
Scanning Tunneling ◽  
Low Density ◽  
Tunneling Microscopy ◽  
Defect Sites ◽  
Island Density

AbstractCopper overlayers deposited on nearly stoichiometric SrTiO3(001) have been investigated with scanning tunneling microscopy (STM). Vapor deposition of Cu on a SrTiO3(001) surface at ambient temperature leads to the formation of three dimensional islands (clusters). The distribution of Cu islands appears to be inhomogeneous with two characteristic morphologies. In regions with a low density of Cu islands the Cu was always associated with step edges or defect sites. In regions with a high density of Cu islands the islands exhibit a random but nearly close packed morphology. The variation of Cu island density is indicative of diffusion of Cu clusters on the SrTiO3(001) surface. Diffusion was further confirmed by annealing the Cu/SrTiO3 at elevated temperatures yielding agglomeration of Cu clusters.

Self-Assembled InAs Islands on (AI,Ga)As, an In Situ Scanning Tunneling Microscopy Study

1999 ◽  
Vol 571 ◽  
Author(s):  
P. Ballet ◽  
J.B. Smathers ◽  
G.J. Salamo
Keyword(s):  
Scanning Tunneling Microscopy ◽  
Molecular Beam ◽  
Three Dimensional ◽  
Microscopy Study ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Self Organized ◽  
Scanning Tunneling Microscopy Study ◽  
Island Density

ABSTRACTWe report an in-situ molecular beam epitaxy – scanning tunneling microscopy study of three dimensional (3D) self organized InAs islands on (AI,Ga)As surfaces. The influence of the presence of Al atoms on the roughness of the starting surface and on the island density is shown by investigating several Al compositions. We emphasize the case of InAs/AlAs and point out the major differences between this system and the widely studied InAs/GaAs system.

DIFFERENT GROWTH BEHAVIOR OF Ge, Al AND Sb ON GRAPHITE

2006 ◽  
Vol 13 (02n03) ◽  
pp. 287-296 ◽  
Author(s):  
WENDE XIAO ◽  
ZHIJUN YAN ◽  
SUNIL SINGH KUSHVAHA ◽  
MAOJIE XU ◽  
XUE-SEN WANG
Keyword(s):  
Double Layer ◽  
Room Temperature ◽  
Pyrolytic Graphite ◽  
Three Dimensional ◽  
Growth Behavior ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Defect Sites ◽  
Unique Nature

Growth of Ge , Al and Sb on highly oriented pyrolytic graphite (HOPG) was systematically investigated using in situ scanning tunneling microscopy (STM). At room temperature (RT), three dimensional (3D) clusters of all three elements nucleate and grow at the step edges and defect sites of HOPG. The clusters of Al and Ge form chains, while Sb islands are mostly isolated. With further deposition at RT, Al clusters grow and coarsen into faceted islands with craters on the top (111) facets, whereas ramified single- and double-layer cluster islands are observed for Ge . When deposited or annealed at T ≥ 175° C , Ge forms crystallites but with randomly oriented facets. As spherical Sb islands grow beyond certain size, (111) facets appear on the top. Additionally, crystalline 2D films and 1D nanorods are observed for Sb deposited at RT. At T ≈ 100° C and higher flux, only the 2D and 1D Sb islands are formed. These different growth behaviors reflect the unique nature in which the atoms (molecules), clusters and crystallites of each element interact with HOPG surface and with each other.

Germanium Nanostructures on Silicon Observed by Scanning Probe Microscopy

MRS Bulletin ◽  
2004 ◽  
Vol 29 (7) ◽  
pp. 484-487 ◽  
Author(s):  
Masahiko Tomitori ◽  
Toyoko Arai
Keyword(s):  
Scanning Probe Microscopy ◽  
Film Growth ◽  
Three Dimensional ◽  
Layer Growth ◽  
Scanning Probe ◽  
Scanning Tunneling ◽  
Layer By Layer ◽  
Tunneling Microscopy ◽  
Probe Microscopy ◽  
History Of

AbstractScanning tunneling microscopy and noncontact atomic force microscopy have been used to observe germanium growth on Si(001) and Si(111). The atomically resolved images provide invaluable information on heteroepitaxial film growth from the viewpoints of both industrial application and basic science. We briefly review the history of characterizing heteroepitaxial elemental semiconductor systems by means of scanning probe microscopy (SPM), where the Stranski–Krastanov growth mode can be observed on the atomic scale:the detailed phase transition from layer-by-layer growth to three-dimensional cluster growth was elucidated by the use of SPM. In addition, we comment on the potential of SPM for examining the spectroscopic aspects of heteroepitaxial film growth, through the use of SPM tips with well-defined facets.

scholarly journals Dual role of CO in the stability of subnano Pt clusters at the Fe3O4(001) surface

2016 ◽  
Vol 113 (32) ◽  
pp. 8921-8926 ◽  
Author(s):  
Roland Bliem ◽  
Jessi E. S. van der Hoeven ◽  
Jan Hulva ◽  
Jiri Pavelec ◽  
Oscar Gamba ◽  
...  
Keyword(s):  
Density Functional ◽  
Elevated Temperatures ◽  
Time Lapse ◽  
Dual Role ◽  
Oxidation Catalyst ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Active Metal ◽  
Catalytically Active ◽  
The Stability

Interactions between catalytically active metal particles and reactant gases depend strongly on the particle size, particularly in the subnanometer regime where the addition of just one atom can induce substantial changes in stability, morphology, and reactivity. Here, time-lapse scanning tunneling microscopy (STM) and density functional theory (DFT)-based calculations are used to study how CO exposure affects the stability of Pt adatoms and subnano clusters at the Fe3O4(001) surface, a model CO oxidation catalyst. The results reveal that CO plays a dual role: first, it induces mobility among otherwise stable Pt adatoms through the formation of Pt carbonyls (Pt1–CO), leading to agglomeration into subnano clusters. Second, the presence of the CO stabilizes the smallest clusters against decay at room temperature, significantly modifying the growth kinetics. At elevated temperatures, CO desorption results in a partial redispersion and recovery of the Pt adatom phase.

Room temperature observation of the correlation between atomic and electronic structure of graphene on Cu(110)

RSC Advances ◽  
2016 ◽  
Vol 6 (100) ◽  
pp. 98001-98009 ◽  
Author(s):  
Thais Chagas ◽  
Thiago H. R. Cunha ◽  
Matheus J. S. Matos ◽  
Diogo D. dos Reis ◽  
Karolline A. S. Araujo ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Chemical Vapor Deposition ◽  
Scanning Tunneling Microscopy ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Temperature Observation ◽  
Atomic And Electronic Structure

We have used atomically-resolved scanning tunneling microscopy and spectroscopy to study the interplay between the atomic and electronic structure of graphene formed on copper via chemical vapor deposition.

Scanning Tunneling Microscope Study of Etch Pits on Highly Oriented Pyrolytic Graphite Heated in an Atomic Absorption Electrothermal Analyzer

1997 ◽  
Vol 51 (12) ◽  
pp. 1896-1904 ◽  
Author(s):  
Kurt G. Vandervoort ◽  
Kristin N. McLain ◽  
David J. Butcher
Keyword(s):  
Elevated Temperatures ◽  
Pyrolytic Graphite ◽  
Reaction Rates ◽  
Surface Reactivity ◽  
Scanning Tunneling ◽  
Highly Oriented Pyrolytic Graphite ◽  
Tunneling Microscopy ◽  
Etch Pits ◽  
Pit Formation ◽  
Second Period

Scanning tunneling microscopy (STM) was used to elucidate monolayer etch pits that form on highly oriented pyrolytic graphite (HOPG) heated in an electrothermal analyzer. Pits form at elevated temperatures due to reactions between oxygen and exposed carbon edge atoms (defects) and additionally with intraplanar carbon atoms (through abstraction). Samples of HOPG without analyte or matrix modifier were placed in the depression of a pure pyrolytic graphite platform and heated by using standard analysis furnace programs. Under argon stop-flow conditions, pits form in less than a second at atomization temperatures equal to and above 1200 °C. With low argon flow rates (40 mL/min), pits formed at atomization temperatures equal to and greater than 1750 °C in less than a second. Quantitative pit formation rates were used to indicate oxygen partial pressure, which may be as high as ∼ 10−3 atm at 1200 °C. Reaction rates were used to predict surface degradation due to oxygen attack and determine that 1-μm depth normal to the surface would be removed by 200 successive 5-second-period furnace firings at 1200 °C. Implications for increases in surface reactivity and analyte intercalation are discussed.

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