Influence of sub-surface damage evolution on low-energy-plasma-driven deuterium permeation through tungsten

Isolated pyramids, 30–80 nm wide and 3–20 nm tall, form during sputter-annealing cycles on the Ge (110) surface. Pyramids have four walls with {19 13 1} faceting and a steep mound at the apex. We used scanning tunneling microscopy (STM) under ultrahigh vacuum conditions to periodically image the surface at ion energies between 100 eV and 500 eV and incremental total flux. Pyramids are seen using Ar+ between 200 eV and 400 eV, and require Ag to be present on the sample or sample holder. We suspect that the pyramids are initiated by Ag co-sputtered onto the surface. Growth of pyramids is due to the gathering of step edges with (16 × 2) reconstruction around the pyramid base during layer-by-layer removal of the substrate, and conversion to {19 13 1} faceting. The absence of pyramids using Ar+ energies above 400 eV is likely due to surface damage that is insufficiently annealed.

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In situ analysis of Si(100) surface damage induced by low-energy rare-gas ion bombardment using x-ray photoelectron spectroscopy

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.580714 ◽

1997 ◽

Vol 15 (3) ◽

pp. 820-824 ◽

Cited By ~ 5

Author(s):

Masahiko Ishii ◽

Yoshiharu Hirose ◽

Toshikazu Sato ◽

Takeshi Ohwaki ◽

Yasunori Taga

Keyword(s):

Photoelectron Spectroscopy ◽

Ion Bombardment ◽

Surface Damage ◽

Low Energy ◽

In Situ Analysis ◽

Rare Gas ◽

X Ray

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Temperature Dependence of Surface Morphology of Silicon Grown on CaF2/Si by Electron Beam Assisted Mbe

MRS Proceedings ◽

10.1557/proc-367-305 ◽

1994 ◽

Vol 367 ◽

Author(s):

P.O. Pettersson ◽

R.J. Miles ◽

T.C. Mcgill

Keyword(s):

Surface Roughness ◽

Electron Beam ◽

Photoelectron Spectroscopy ◽

Silicon Layer ◽

Surface Damage ◽

Low Energy ◽

Growth Mode ◽

Optimal Range ◽

Low Energy Electrons ◽

Ordered Array

AbstractWe present the results of electron beam assisted molecular beam epitaxy (EB-MBE) on the growth mode of silicon on CaF2/Si(111). By irradiating the CaF2 surface with low energy electrons, the fluorine is desorbed, leaving an ordered array of F-centers behind. Using atomic force microscopy (AFM), we do not detect any surface damage on the CaF2 layer due to the low energy electron irradiation. The surface free energy of the CaF2 is raised due to the F-center array and the subsequent silicon layer is smoother. Using AFM and X-ray photoelectron spectroscopy (XPS), we find an optimal range of exposures for high temperature (650°C) growth of the silicon overlayer that minimizes surface roughness of the silicon overlayer and we present a simple model based on geometrical thermodynamics to explain this.We observed a similar optimal range of exposures that minimizes the surface roughness for medium (575°C) and low (500°C) growth temperatures of the silicon layer. We present an explanation for this growth mode based on kinetics.

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