A single-electron stochastic associative processing circuit robust to random background-charge effects and its structure using nanocrystal floating-gate transistors
T. Yamanaka et al., A single-electron stochastic associative processing circuit robust to random background-charge effects and its structure using nanocrystal floating-gate transistors, NANOTECHNOL, 11(3), 2000, pp. 154-160
A new single-electron circuit using the unique features of single-electron
devices is proposed, based on a basic strategy and circuit architecture for
achieving large-scale integration. A unit circuit consisting of a single-e
lectron transistor and a capacitor operates as an exclusive-NOR gate by the
Coulomb blockade effect, and its transient behaviour is stochastic due to
electron-tunnelling events. Using this unit circuit, a stochastic associati
ve processing circuit is proposed, based on a new information-processing pr
inciple where the association probability depends on the similarity between
the input and reference data. This circuit can be constructed by using a s
ilicon nanocrystal floating-gate structure in which dots are regularly arra
nged on a gate electrode of a MOSFET. The simulation results uf a simple di
git pattern association demonstrate the successful stochastic operation. Th
e background-charge effects on the proposed circuit are analysed and simula
ted, and it is shown that the circuit is much more robust to such effects t
han the conventional single-electron logic circuits.