Semiconductor memory having both volatile and non-volatile functionality comprising resistive change material and method of operating
A semiconductor memory cell including a capacitorless transistor having a floating body configured to store data as charge therein when power is applied to the cell, and a non-volatile memory comprising a bipolar resistive change element, and methods of operating.
1. An integrated circuit comprising:
a semiconductor memory array comprising:
a plurality of memory cells arranged in a matrix of rows and columns, wherein at least two of said memory cells each include:
a capacitorless transistor having a floating body configured to store data when power is applied to said memory cell; and
a non-volatile memory comprising a bipolar resistive change element;
wherein said floating body is configured to be charged to a level indicative of a state of the memory cell based on resistivity of said bipolar resistive change element, upon restoration of power to said memory cell during a restore operation;
wherein when said resistivity of said bipolar resistive change element of a first memory cell of said at least two of said memory cells is in a first resistivity level and said resistivity of said bipolar resistive change element of a second memory cell of said at least two of said memory cells is in a second resistivity level, upon restoration of power to said memory array, said floating body of said first memory cell of said at least two of said memory cells is charged to a first charge level as volatile memory and said floating body of said second memory cell of said at least two of said memory cells is charged to a second charge level as volatile memory; and
a control circuit configured to perform said restore operation, wherein said restore operation is performed in parallel on said at least two of said memory cells.
2. The integrated circuit of claim 1 , wherein said memory cell functions as volatile memory upon said restoration of power to said memory cell.
3. The integrated circuit of claim 1 , wherein said floating body is configured to a predetermined state prior to being charged based on said resistivity of said bipolar resistive change element.
4. The integrated circuit of claim 1 , wherein said bipolar resistive change element is configured to a predetermined resistivity level after said floating body is charged to a level based on said resistivity of said bipolar resistive change element.
5. The integrated circuit of claim 1 , wherein said capacitorless transistor comprises a first region in electrical contact with said floating body and a second region spaced apart from said first region and in electrical contact with said floating body.
6. The integrated circuit of claim 1 , wherein said bipolar resistive change element comprises a material selected from at least one of: transition metal oxide materials, ferroelectric materials and ferromagnetic materials.
7. The integrated circuit of claim 1 , wherein said bipolar resistive change element is electrically connected to said floating body and a distance between said bipolar resistive change element and said floating body, when electrically connected, is in the range from about 90 nm to 1 μm.
8. The integrated circuit of claim 1 , further comprising an addressable line electrically connected to said bipolar resistive change element.
9. The integrated circuit of claim 8 , further comprising a conductive material element interconnecting said addressable line and said bipolar resistive change element.
10. The integrated circuit of claim 1 comprising a three-dimensional structure comprising a fin structure comprising said floating body, extending substantially perpendicular to, and above a top surface of a substrate.
11. A semiconductor memory array comprising:
a plurality of memory cells arranged in a matrix of rows and columns, wherein at least two of said memory cells each include:
a bipolar device configured to store data when power is applied to said memory cell; and
a nonvolatile memory comprising a bipolar resistive change element configured to store data stored in said bipolar device upon transfer thereto;
wherein said data stored in said bipolar device determines a resistivity of said bipolar resistive change element upon transfer thereto;
wherein said transfer is performed to said at least two of said memory cells in parallel; and
wherein when said data stored in said bipolar device of a first memory cell of said at least two of said memory cells represents a first state and said data stored in said bipolar device of a second memory cell of said at least two of said memory cells represents a second state, upon transfer of said data representing said first and second states respectively to said bipolar resistive change elements of said first and second memory cells, said bipolar resistive change element of said first memory cell of said at least two of said memory cells is configured to a first resistivity level as nonvolatile memory and said bipolar resistive change element of said second memory cell of said at least two of said memory cells is configured to a second resistivity level as nonvolatile memory.
12. The semiconductor memory array of claim 11 , wherein each said bipolar resistive change element comprises a material selected from at least one of: transition metal oxide materials, ferroelectric materials and ferromagnetic materials.
13. The semiconductor memory array of claim 11 , wherein said bipolar resistive change element is electrically connected to said bipolar device and a distance between said bipolar resistive change element and said bipolar device, when electrically connected, is in the range from about 90 nm to 1 μm.
14. The semiconductor memory array of claim 11 , further comprising an addressable line electrically connected to said bipolar resistive change element.
15. The semiconductor memory array of claim 14 , further comprising a conductive material element interconnecting said addressable line and said bipolar resistive change element.
16. The semiconductor memory array of claim 11 , wherein said bipolar device comprises a floating base region.
17. The semiconductor memory array of claim 16 , wherein said floating base region has a first conductivity type selected from n-type conductivity type and p-type conductivity type.
18. The semiconductor memory array of claim 16 , wherein charge stored in said floating base region represents said data stored in said bipolar device.
19. The semiconductor memory array of claim 11 , wherein said bipolar device has a three-dimensional structure comprising a fin structure extending substantially perpendicular to, and above a top surface of a substrate.
20. An integrated circuit comprising:
a plurality of memory cells arranged in a matrix of rows and columns, wherein at least two of said memory cells each include:
a bipolar device configured to store data when power is applied to said memory cell; and
a nonvolatile memory comprising a bipolar resistive change element configured to store data stored in said bipolar device upon transfer thereto;
wherein said data stored in said bipolar device determines a resistivity of said bipolar resistive change element upon transfer thereto;
wherein said transfer is performed to said at least two of said memory cells in parallel;
wherein when said data stored in said bipolar device of a first memory cell of said at least two of said memory cells represent a first state and said data stored in said bipolar device of a second memory cell of said at least two of said memory cells represents a second state, upon transfer of said data representing said first and second states respectively to said bipolar resistive change elements of said first and second memory cells, said bipolar resistive change element of said first memory cell of said at least two of said memory cells is configured to a first resistivity level as nonvolatile memory and said bipolar resistive change element of said second memory cell of said at least two of said memory cells is configured to a second resistivity level as nonvolatile memory; and
a circuitry configured to perform said transfer.
21. The integrated circuit of claim 20 , wherein said resistance change element comprises a material selected from at least one of: transition metal oxide materials, ferroelectric materials and ferromagnetic materials.
22. The integrated circuit of claim 20 , wherein said bipolar resistive change element is electrically connected to said bipolar device and a distance between said bipolar resistive change element and said bipolar device, when electrically connected, is in the range of from about 90 nm to 1 μm.
23. The integrated circuit of claim 20 , further comprising an addressable line electrically connected to said bipolar resistive change element.
24. The integrated circuit of claim 20 , wherein said bipolar resistive change element comprises a bipolar resistive change material and a conductive material element interconnecting said addressable line and said bipolar resistive change material.
25. The integrated circuit of claim 20 , wherein said bipolar device comprises a floating base region.
26. The integrated circuit of claim 25 , wherein said floating base region has a first conductivity type selected from n-type conductivity type and p-type conductivity type.
27. The integrated circuit of claim 25 , wherein charge stored in said floating base region represents said data stored in said bipolar device.
28. The integrated circuit of claim 20 , wherein said bipolar device has a three-dimensional structure comprising a fin structure extending substantially perpendicular to, and above a top surface of a substrate.