Ultraviolet laser‐induced interaction of Cl2with GaAs(110)
作者:
G. Haase,
V. Liberman,
R. M. Osgood,
期刊:
Journal of Vacuum Science&Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena
(AIP Available online 1992)
卷期:
Volume 10,
issue 1
页码: 206-215
ISSN:1071-1023
年代: 1992
DOI:10.1116/1.586303
出版商: American Vacuum Society
关键词: GALLIUM ARSENIDES;CHLORINE MOLECULES;ULTRAVIOLET RADIATION;LASER RADIATION;PHOTODISSOCIATION;ADSORPTION;SURFACE REACTIONS;ULTRAHIGH VACUUM;LOW TEMPERATURE;PHOTON STIMULATED DESORPTION;ARSENIC CHLORIDES;ETCHING;PHOTOCHEMICAL REACTIONS;GaAs
数据来源: AIP
摘要:
We have studied the ultraviolet laser‐induced interaction of molecular chlorine with a well‐defined GaAs(110) surface under ultrahigh vacuum conditions. Without illumination, chlorine was found to adsorb both molecularly and dissociatively at 85 K. Illumination of a molecular chlorine‐covered surface at 85 K with 193, 248, and 351 nm radiation led to the desorption of Cl atoms and to the formation of AsCl3. We suggest that the surface reaction, that is responsible for the AsCl3formation, is initiated by molecular chlorine dissociation. While direct absorption by an individual Cl2molecule may be the cause for the chlorine dissociation at 351 nm, we propose an intermolecular charge–transfer absorption within the condensed Cl2overlayer for the cases of 248 and 193 nm. Support for this mechanism comes from the dependence of time‐of‐flight distributions and AsCl3coverage measurements on the molecular chlorine surface coverage, on the laser wavelengths and on the use of different substrates.
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