A single-channel, single-poly floating gate (
EEPROM-type)
memristor including asymmetric source / drain-to-gate
coupling and an asymmetric channel
doping pattern. Asymmetric source / drain-to-gate
coupling is achieved by configuring the drain, source and floating gate such that the gate-to-drain
capacitance is greater than the gate-to-source
capacitance. The asymmetric channel
doping pattern is implemented by forming different drain-side and source-side
doping portions (i.e., different N-type or P-type
implant configurations and / or positions). The asymmetric channel doping pattern is preferably formed using standard
CMOS implants (e.g., NLDD and P-type pocket implants). Multiple N-type and P-type implants may be selectively positioned to achieve a desired balance between program / erase speeds, reverse (read direction)
threshold voltage and
immunity to read-disturb and over-erase. A drain-side
diode may be additionally used to suppress over-erase. A memory circuit including multiple two-terminal memristors disposed in a cross-point array is disclosed, which can be utilized, e.g., in a neuromorphic circuit.