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As-rich GaAs(001) surfaces observed during As4-irradition by scanning tunneling microscopy

Shiro Tsukamoto·Markus Pristovsek·Bradford G. Orr·Akihiro Ohtake·Gavin R. Bell·Nobuyuki Koguchi
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Abstract

As-rich GaAs (001) surfaces are successfully observed during As4-irradition by a system in which scanning tunneling microscopy (STM) and molecular beam epitaxy can be performed simultaneously. With a substrate temperature of 440 C and an As4 partial pressure of 2x10-6 torr, reflection high energy electron diffraction patterns and reflectance anisotropy spectra confirm a c(4x4) As-stabilized surface. STM images clearly show alteration of the surface reconstructions while scanning. It is postulated that continual attachment / detachment of As molecules to and from the surface produces the observed dynamic behavior.

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Shiro Tsukamoto, Markus Pristovsek, Bradford G. Orr, Akihiro Ohtake, Gavin R. Bell, Nobuyuki Koguchi. 2002-02-05. As-rich GaAs(001) surfaces observed during As4-irradition by scanning tunneling microscopy. https://arxiv.org/abs/physics/0202013

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