Scanning tunneling microscopy (STM) studies of the chemical vapor deposition of Ge on Si(111) from Ge hydrides and a comparison with molecular beam epitaxy

Wintterlin, J.; Avouris, Ph.
January 1994
Journal of Chemical Physics;1/1/1994, Vol. 100 Issue 1, p687
Academic Journal
Scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS), and tip-induced desorption are used to study the mechanism of the chemical vapor deposition (CVD) of Ge on Si(111)-7×7 from GeH4 and Ge2H6. The chemical and structural changes that follow the dissociation of the hydride molecules are investigated as a function of the substrate temperature, and the structure and growth mode of the resulting films are compared to those of films generated by molecular beam epitaxy (MBE). At room temperature, only Ge2H6 reacts appreciably with the Si(111) surface. The reaction proceeds via a mobile precursor state, but does not exhibit a site selectivity with respect to surface sites of the 7×7 unit cell. For temperatures in the neighborhood of 400 °C, continuous film growth is observed for both GeH4 and Ge2H6, despite the fact that hydrogen is present at the surface. The film growth mode undergoes a qualitative change in a relatively narrow temperature range ∼400 °C. At 370 °C, the film grows in the form of monolayers with a hydrogen-stabilized 1×1 structure. This is in contrast to growth by MBE which involves 7×7 and 5×5 reconstructed bilayers. At the same time, a highly site-selective substrate etching process favoring the center-adatom sites is observed and characterized. This etching process leads to a chemically induced Si–Ge intermixing at the growing interface. At 430 °C, the CVD film growth mode involves bilayers with 7×7 and 5×5 reconstructions, but in addition, areas with a new [Square_Root]3 ×[Square_Root]3R30° reconstruction which is not observed in MBE are formed. Short-lived GeH species acting similarly to column III elements are probably the building blocks of this structure. We show that all of the above observations can be understood by considering the effect of hydrogen on the film growth process. The ability of the hydrogen to influence the growth...


Related Articles

  • A UHV STM for in situ characterization of MBE/CVD growth on 4-inch wafers. Leifeld, O.; Müller, B.; Grützmacher, D.A.; Kern, K. // Applied Physics A: Materials Science & Processing;1998, Vol. 66 Issue 7, pS993 

    Abstract. A UHV STM has been designed for combination with a multipurpose MBE/UHV-CVD system. A small UHV chamber containing the STM is attached to the load lock of the MBE chamber for sample transfer. For high-resolution measurements, the STM chamber is detached from the MBE/CVD machine to...

  • Scanning Tunnelling Spectroscopic Studies of Dirac Fermions in Graphene and Topological Insulators. N.-C. Yeh; Teague, M. L.; R. T.-P. Wu; H. Chu; Boyd, D. A.; Bockrath, M. W.; L. He; F.-X. Xiu; K.-L. Wang // EPJ Web of Conferences;2012, Issue 23, p00021-p.1 

    We report novel properties derived from scanning tunnelling spectroscopic (STS) studies of Dirac fermions in graphene and the surface state (SS) of a strong topological insulator (STI), Bi2Se3. For mono-layer graphene grown on Cu by chemical vapour deposition (CVD), strain-induced scalar and...

  • High temperature scanning tunneling microscopy during molecular beam epitaxy. Voigtlander, Bert; Zinner, Andre; Weber, Thomas // Review of Scientific Instruments;Jul96, Vol. 67 Issue 7, p2568 

    Examines a system that is capable of simultaneous molecular beam deposition and scanning tunneling microscopy (STM) imaging. Effects of the active compensation of thermal drift on the residual drift in the images; Measurements at varying sample temperatures; Feasibility of simultaneous...

  • Morphology of molecular beam epitaxy grown NiAl on GaAs studied by scanning tunneling microscopy. Hirono, S.; Tanimoto, M. // Applied Physics Letters;7/5/1993, Vol. 63 Issue 1, p69 

    Examines the morphology of molecular beam epitaxy grown nickel-aluminum on gallium arsenide by scanning tunneling microscopy. Insensitivity of reflection high energy electron diffraction streaks to the trenches; Effect of the substrate temperature on terraces; Association of trench formation...

  • Simultaneous molecular beam epitaxy growth and scanning tunneling microscopy imaging during.... Voigtlander, Bert; Zinner, Amdre // Applied Physics Letters;11/29/1993, Vol. 63 Issue 22, p3055 

    Presents a scanning tunneling microscope capable of simultaneously imaging and molecular beam epitaxy growth at 600-900 Kelvin sample temperature. Formation of the Stranski-Krastanov layer; Inversion of the aspect ratio of the islands with increasing coverage; Advantage of the device.

  • Effects of surface reconstruction on III-V semiconductor interface formation: The role of... Nosho, B.Z.; Weinberg, W.H. // Applied Physics Letters;3/22/1999, Vol. 74 Issue 12, p1704 

    Studies the effects of surface reconstruction on III-V semiconductor interface formation using molecular-beam epitaxy and in situ scanning tunneling microscopy. Controlling the roughness on the atomic scale; Probability of the occurrence of roughness in all heterostructures where the growth...

  • Selective area growth of metal nanostructures. Adams, D.P.; Mayer, T.M. // Applied Physics Letters;4/15/1996, Vol. 68 Issue 16, p2210 

    Examines the selective area growth of metal nanostructures. Fabrication of nanometer-scale metal lines onto silicon(100) substrate by scanning tunneling microscope (STM) based lithography and chemical vapor deposition; Use of STM tip to define areas for metal layer growth; Exposure of...

  • Effects of mixing germane in silane gas-source molecular beam epitaxy. Ki-Joon Kim; Suemitsu, Maki; Yamanaka, Masayoshi; Miyamoto, Nobuo // Applied Physics Letters;6/28/1993, Vol. 62 Issue 26, p3461 

    Examines the effect of mixing germane on silane gas-source molecular beam epitaxy. Deliberation of the properties of ultra-high vacuum chemical vapor deposition; Link between the growth-rate reduction at low temperatures and the increase of the surface hydrogen coverage; Growth mechanism of...

  • Molecular stream epitaxy and the role of the boundary layer in chemical vapor deposition. Katsuyama, T.; Bedair, S. M. // Journal of Applied Physics;5/15/1988, Vol. 63 Issue 10, p5098 

    Provides information on a study concerning the application of molecular stream epitaxy in boundary layer in chemical vapor deposition. Discussion of the processes of metalorganic chemical vapor deposition; Observation on the behavior of superlattices and reactant gases; Factors which effect...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics