Silicon Obtained by MILC and SILC Techniques: Application for Top-Down Litography Nanostructures
Résumé
Thanks to their integration properties and their high surface to
volume ratio, silicon nanostructures (nanowires, nanoribbons) offer great
potential for high integration electronics or highly sensitive sensors in a fully
compatible silicon technology. Amorphous silicon can be crystallized by using
Solid Phase Crystallization (SPC) technique. This technique leads a high density
of structural defects in nanostructures. So we use two annealing techniques:
Metal Induced Lateral Crystallization (MILC) and Seed Induced Lateral
Crystallization (SILC) in order to get high quality crystallized silicon for
nanostructures. Those two methods involve the deposition of a thin layer of
nickel on a layer of amorphous silicon. For the SILC solution the metal is
removed before the annealing performed at a temperature as low as 500°C. A
crystallization front is observed and Secco etching reveals needle-like crystals
with homogenous sizes. These nanocrystals show a preferred direction with a
growth perpendicular to the crystallization front. Optical (Raman, SEM) and
electrical (I(T), I(V)) measurements are performed on silicon nanostructures
crystallized by using SPC, MILC and SILC methods. A guided MILC or SILC, on a
pre-patterned amorphous silicon nanostructures using conventional lithography,
can be useful for the manufacturing of high crystal quality silicon nanowires or
nanoribbons based devices such as electronic components or sensors in a
classical silicon technology.