Abstract
One-step formation of silicon nanowires, sheets, and texture
surface on a silicon substrate has been achieved using
hydrogen-radical etching reactions. Metallic tungsten and for
comparison purposes a tungsten hot wire, were used as catalysts
for the hydrogen-molecular cracking. It was shown that a
variety of surface structures on silicon such as inverted pyramid
texture, V-groove texture, dense silicon nanowire growth over
texture, and nanosheet structure can be obtained by controlling
the process conditions. The obtained results suggested that
the formation of nanotungsten silicide particle is an essential
prerequisite to obtain these structures. The particles work as
an etching mask against hydrogen-radical etching, as well as a
catalyst for vapor–solid–solid (VSS) growth. SEM, TEM,
micro-RAMAN, and XPS were used for the analysis of the
hydrogen-radical-treated Si samples. The Si nanowires growth
model, as well as the texturing mechanism initiated by
hydrogen-radical treatment of Si surface in the presence of
tungsten nanoparticle is discussed. It is concluded that the
proposed acid-free method, which is based on a modification of
Si surfaces only by hydrogen radicals, can be considered as a
“green” technology approach, which can be used for the costeffective
fabrication of silicon nanostructures, which can be
considered as a base for several types of advanced devices in
the future.
surface on a silicon substrate has been achieved using
hydrogen-radical etching reactions. Metallic tungsten and for
comparison purposes a tungsten hot wire, were used as catalysts
for the hydrogen-molecular cracking. It was shown that a
variety of surface structures on silicon such as inverted pyramid
texture, V-groove texture, dense silicon nanowire growth over
texture, and nanosheet structure can be obtained by controlling
the process conditions. The obtained results suggested that
the formation of nanotungsten silicide particle is an essential
prerequisite to obtain these structures. The particles work as
an etching mask against hydrogen-radical etching, as well as a
catalyst for vapor–solid–solid (VSS) growth. SEM, TEM,
micro-RAMAN, and XPS were used for the analysis of the
hydrogen-radical-treated Si samples. The Si nanowires growth
model, as well as the texturing mechanism initiated by
hydrogen-radical treatment of Si surface in the presence of
tungsten nanoparticle is discussed. It is concluded that the
proposed acid-free method, which is based on a modification of
Si surfaces only by hydrogen radicals, can be considered as a
“green” technology approach, which can be used for the costeffective
fabrication of silicon nanostructures, which can be
considered as a base for several types of advanced devices in
the future.
