Perceptron Circuit Using Lead Phthalocyanine Films

Evaporated films of lead phthalocyanine exhibit a unique conductivity change via applied DC voltage. The change depends on the polarity and the strength of the input voltage and has a memory effect. The change is also observed when pulsed voltage is applied. In such a case, the change is multiplied by the input pulse itself because of the memory effect. Therefore, the change can be regarded as synaptic plasticity. Using the lead phthalocyanine films as synaptic connections, we constructed a perceptron circuit, which is one of the artificial neural networks, and demonstrated that the circuit can classify input patterns.