In a matrix-addressable apparatus comprising one or more memory devices
with multidirectionally switchable memory cells arranged in a passive
matrix-addressable array, the memory cells comprised a memory medium in
the form of a ferroelectric or electret, thin-film memory material capable
of being polarized by an applied electric field and exhibiting hysteretic,
and preferable the memory material is a polymer or copolymer. A memory
device in the apparatus comprised at least a first and second electrode
means such that the electrodes of the second electrode means are provided
in recesses in the electrodes of the first electrode means and oriented
orthogonally thereto, the recesses extending only half-way through the
electrodes of the first electrode means. The electrodes of the second
electrode means are provided in the recesses surrounded by memory material
which also contacts the crossing electrodes of the first electrode means
whereby a memory cell is defined in the crossing between electrodes of the
first and second electrode means respectively and formed by a memory
material surrounding the electrodes of the second means on at least three
sides thereof, thus providing at least three switching directions in the
memory cell at different locations thereof.
