Non-volatile memory with a single transistor and resistive memory element

1. A non-volatile RAM memory array comprising:

a plurality of memory cells formed on a semiconductor substrate, each cell capable of being selected through a select line and a data line, whereby the select line and the data line are perpendicular to each other, and having

a single transistor that controls current flow through the memory cell depending on a voltage applied to the select line;

a memory element including a perovskite that

changes its resistive state from a high resistive state to a low resistive state upon application of a first voltage pulse across the memory element;

changes its resistive state from the low resistive state to the high resistive state upon application of a second voltage pulse across the memory element, the second voltage pulse across the memory element being of opposite polarity to the first voltage pulse; and

maintains the resistive state even if power ceases to be supplied to the memory cell;

wherein the resistive state of the memory cell determines the information stored in the memory cell.

2. The non-volatile RAM memory army of claim 1 , wherein:

the single transistor has a first terminal, a second terminal, and either a gate or a base;

the first terminal of the single transistor is in electrical contact with the data line;

the second terminal of the single transistor is in electrical contact with the memory element;

the gate or base of the single transistor is in electrical contact with the select line; and

a reference line that provides a reference voltage to the memory cell is in electrical contact with the memory element, whereby a voltage across the memory element is determined by a voltage applied to the second terminal and the reference voltage.

3. The non-volatile RAM memory array of claim 2 , wherein varying a voltage applied to the data line is operative to vary the voltage across the memory element.

4. The non-volatile RAM memory array of claim 3 , wherein:

the voltage applied to the data line comprises a voltage selected from the group consisting of a read voltage, a write 1 voltage, and a write 0 voltage; and

the voltage applied to the select line comprises a selected one of a select voltage or an unselect voltage;

whereby the read voltage causes the voltage across the memory element to be insufficient to cause a change in resistive state, the write 1 voltage causes the voltage across the memory element to be equal to the first voltage pulse when the select line is set to the select voltage, and the write 0 voltage causes the voltage across the memory element to be equal to the second voltage pulse when the select line is set to the select voltage.

5. The non-volatile RAM memory array of claim 4 , wherein the voltage applied to the data line comprises a selected one of a select data line voltage or an unselect data line voltage.

6. The non-volatile RAM memory array of claim 5 , wherein the unselect data line voltage is equal to the reference voltage.

7. The non-volatile RAM memory array of claim 6 , wherein the reference voltage is equal to ground.

8. The non-volatile RAM memory array of claim 1 , wherein the select line is polysilicon material.

9. A non-volatile RAM memory array, comprising:

a plurality of memory cells formed on a semiconductor substrate, each cell capable of being selected through a select line and a data line, and having

a single semiconductor device that is formed on the semiconductor substrate and controls current flow depending on a voltage applied to the select line; and

a memory element including a perovskite that changes its resistive state between a low resistive state and a high resistive state upon application of a voltage pulse, wherein the resistive state of the memory cell determines the information stored in the memory cell; and

wherein the information stored in the plurality of memory cells can be maintained in the absence of power.

10. The non-volatile RAM memory array of claim 9 , wherein multiple non-volatile RAM memory arrays are used in a single memory chip.

11. The non-volatile RAM memory array of claim 9 , wherein the semiconductor device is a FET.

12. The non-volatile RAM memory array of claim 9 , wherein the semiconductor device is a pnp bipolar transistor.

13. The non-volatile RAM memory array of claim 12 , wherein the pnp bipolar transistor is a parasitic pnp transistor.

14. The non-volatile RAM memory array of claim 9 , wherein the semiconductor device is a npn bipolar transistor.

15. The non-volatile RAM memory array of claim 9 wherein any layers fabricated between the semiconductor substrate and the memory cell use materials that can withstand high temperature processing.

16. The non-volatile RAM of claim 9 wherein the memory element is deposited using high temperature processing.

17. A non-volatile RAM memory array comprising:

a plurality of memory cells formed on a semiconductor substrate, the semiconductor substrate including a single semiconductor device that controls current flow;

a first electrode layer;

a memory element including a perovskite formed on the first electrode that

changes its resistive state from a high resistive state to a low resistive state upon application of a first voltage pulse across the memory element;

changes its resistive state from the low resistive state to the high resistive state upon application of a second voltage pulse across the memory element, the second voltage pulse across the memory element being of opposite polarity to the first voltage pulse; and

maintains the resistive state even if power ceases to be supplied to the memory cell; and

a second electrode layer formed on the memory element;

wherein the resistive state of the memory cell determines the information stored in the memory cell.