CMOx™ Device

The memory effect of CMOx™ is created by moving Oxygen ions between two metal oxides under electric field.

CMOx™ is powered by the physics of Oxygen vacancy movement, which is entirely different from the physics of electrons that makes NAND work.
  • CMOx™ is a two layer structure comprised of a conductive metal oxide (CMO) and a second insulating metal oxide (IMO).
  • The CMO and IMO each have crystal structures conducive to the trapping and releasing of Oxygen ions.
    • The CMO is an ionic conductor and electronic conductor.
    • The IMO is an ionic conductor and electronic insulator.
  • During the fabrication of CMOx™, the metals ratio within the IMO and CMO are adjusted to optimize the CMOx™ memory cell’s characteristics.

The CMOx™ memory cell is a two terminal device: the IMO and CMO are fabricated between two electrodes (top and bottom). By way of contrast, the NAND memory cell is a three terminal device: source, drain and gate.

In the erased state, Oxygen ions are concentrated in the CMO.

When an electric field is applied from the direction of the CMO towards the IMO, the Oxygen ions move to the IMO. The increased concentration of Oxygen ions in the IMO increases the resistivity of the IMO. Unity’s design IP includes sensing algorithms and sensing circuitry to detect the changes in the electrical properties of the CMO and IMO. Thus the current through the selected cell are compared versus a reference to detect this programmed state of the CMOx™.

When an electric field is applied from the direction of the IMO to the CMO, the Oxygen ions move back to the CMO. The decreased Oxygen ion concentration in the IMO decreases the resistivity of the IMO. Unity then compares the current through the selected cell with a reference as described above.

Unity has demonstrated tens of thousands of cycles through CMOx™ cells.

By using a specific electric field, Unity can change the location of ions and thereby precisely set the cell current. This precise cell current tuning enables multi-level cell architecture.

  • Simple geometry, simple device physics.
  • No forming, not filamentary.
  • Currents defined by geometry of the device (IMO thickness and area).
  • Uniform conduction and area scaling of program, erase, and read current.
  • Full control over currents by controlling the electric field.

View this animation to see how our memory works.