Amorphous- and
polycrystalline-silicon semiconductor devices
In
recent years amorphous and polycrystalline
silicon have become important for a number of applications, e.g., for
the
fabrication of thin-film transistors used in flat-panel displays. Early
investigations
were carried out, based on a steady-state implementation [18,71,76].
Later, a systematic
investigation was carried out about the generation-recombination
mechanisms
involving deep and tail states within the energy gap. A significant
achievement
came from exploiting the local nature of the continuity equations for
the gap states:
it led to incorporating the dynamics of these states into the customary
model
used for crystalline material, without increasing the number of
partial-differential
equations to be solved. An extensive activity for the analysis and
model validation
of amorphous- and polycrystalline-silicon devices, in the steady-state,
small-signal,
and transient regimes, and incorporating different types of tunnel
mechanisms
that are relevant for the device functioning, has been carried out.
Most of it
is in the frame of national or international collaboration with
Laboratories
where thin-film transistors are fabricated
[38,39,44,50,97,98,99,103,105,107,114,116,138].