Method for reading a third-dimensional embedded re-writeable non-volatile memory and registers
View Patent ↗A non-volatile register includes register logic connected with first and second ends of a memory element. The register logic is positioned below the memory element. The memory element may be a two-terminal memory element configured to store data as a plurality of conductivity profiles that can be non-destructively determined by applying a read voltage across the two terminals. New data can be written to the two-terminal memory element by applying a write voltage of a predetermined magnitude and/or polarity across the two terminals. The two-terminal memory element retains stored data in the absence of power. A reference element including a structure that is identical or substantially identical to the two-terminal memory element may be used to generate a reference signal for comparisons during read operations.
1. A method, comprising:
applying a first voltage across a memory element;
sensing a second voltage corresponding to a resistive state of the memory element; and
comparing the second voltage to a reference voltage to define a datum stored in the memory element;
wherein the memory element is configured to store data as a plurality of conductivity profiles and to retain the data in the absence of electrical power: and
wherein the memory element comprises:
a conductive oxide including mobile oxygen ions; and
an electrolytic tunnel barrier electrically in series with the conductive oxide.
2. The method of claim 1 , further comprising:
amplifying a difference between the second voltage and the reference voltage; and
generating a comparison output based at least in part on the difference.
3. The method of claim 2 , further comprising storing the comparison output.
4. The method of claim 3 , further comprising substantially synchronizing the comparison output with an enable signal or a clock signal.
5. The method of claim 1 ,
wherein the electrolytic tunnel barrier comprises a thickness that is less than approximately 50 Angstroms.
6. The method of claim 1 ,
wherein the memory element is integrally fabricated directly above a silicon substrate;
wherein the silicon substrate comprises circuitry fabricated on the silicon substrate; and
wherein the circuitry comprises register logic electrically coupled with the memory element.
7. The method of claim 6 , wherein the memory element is embedded in a memory plane that is integrally fabricated directly above and is in direct contact with the silicon substrate.
8. The method of claim 7 ,
wherein the memory plane comprises a two-terminal cross-point array having a plurality of conductive array lines;
wherein the memory element is positioned between a cross-point of a unique pair of the conductive array lines;
wherein a first terminal and a second terminal of the memory element are electrically coupled with the unique pair of the conductive array lines;
wherein the memory element is directly electrically in series with the unique pair of conductive array lines; and
wherein the unique pair of conductive array lines electrically couple the memory element with the register logic.
9. A method, comprising:
applying a read voltage to a memory element;
sensing a sensed voltage corresponding to a resistance of the memory element;
comparing the sensed voltage to a reference voltage; and
determining a datum stored in the memory element based on the comparison;
wherein the memory element comprises:
a conductive oxide including mobile oxygen ions; and
an electrolytic tunnel barrier electrically in series with the conductive oxide.
10. The method of claim 9 , further comprising:
amplifying a difference between the sensed voltage and the reference voltage; and
generating a comparison output based at least in part on the difference.
11. The method of claim 10 , further comprising storing the comparison output.
12. The method of claim 10 , further comprising substantially synchronizing the comparison output with an enable signal or a clock signal.
13. The method of claim 9 , wherein the memory element is configured to store data as a plurality of conductivity profiles and to retain the data in an absence of electrical power.
14. The method of claim 13 , wherein the electrolytic tunnel barrier comprises a thickness that is less than approximately 50 Angstroms.
15. The method of claim 14 ,
wherein the conductive oxide and the electrolytic tunnel barrier are serially coupled to a first terminal and a second terminal of the memory element.
16. The method of claim 14 ,
wherein the memory element is embedded in a memory plane fabricated above a silicon substrate; and
wherein register logic electrically coupled to the memory element is fabricated on the silicon substrate.
17. The method of claim 16 ,
wherein the memory plane comprises a two terminal cross-point array having a plurality of conductive lines;
wherein a first terminal and a second terminal of the memory element are coupled between a pair of conductive lines; and
wherein the pair of conductive lines electrically couple the memory element to the register logic.