Neuromorphic device and unit synapse device forming the same
View Patent ↗Disclosed are a neuromorphic device and a unit synapse devices forming the same. The unit synapse device has a learning device and an inference device. The learning device and the inference device may share a via oxide layer and a common electrode, and a learning operation and an inference operation may be performed in one unit synapse device.
1 . A unit synapse device, comprising:
a cumulative stack portion formed on a substrate; and
a through-hole portion formed through the cumulative stack portion,
wherein the through-hole portion has a via oxide layer in contact with the cumulative stack portion and a common electrode configured to fill an inside of the via oxide layer, and a learning operation or an inference operation is performed,
wherein the cumulative stack portion comprises:
a first functional metal layer formed on the substrate and having oxygen-reactive metal;
a second interlayer dielectric formed on the first functional metal layer; and
a second functional metal layer having ion source metal formed on the second interlayer dielectric,
wherein the first functional metal layer, the via oxide layer, and the common electrode have a configuration of an interface random access memory (I-RAM) and serve as a learning device for performing the learning operation, and
wherein the second functional metal layer, the via oxide layer, and the common electrode have a configuration of a conductive bridge random access memory (CBRAM) and serve as an inference device for performing the inference operation.
2 . The unit synapse device of claim 1 , wherein the first functional metal layer is electrically connected to a first word line, the second functional metal layer is electrically connected to a second word line, and the common electrode is electrically connected to a bit line.
3 . The unit synapse device of claim 2 , wherein
a first weight is stored in the learning device through the first word line, the first weight is output through the bit line, and
a second weight selected among first weights is transferred to the inference device through the bit line.
4 . The unit synapse device of claim 1 , wherein the learning device and the inference device share the via oxide layer and the common electrode.
5 . The unit synapse device of claim 1 , wherein an oxygen ion vacancy is formed inside the via oxide layer by a voltage applied between the first functional metal layer and the common electrode, and an oxide layer is formed on a surface of the first functional metal layer.
6 . The unit synapse device of claim 1 , wherein a conductive filament is formed inside the via oxide layer by a voltage applied between the second functional metal layer and the common electrode.