Memory array comprising memory cells of Z2-FET type
A memory array includes memory cells of Z 2 -FET type arranged in rows and columns, wherein each memory cell includes a MOS-type selection transistor and a first region of a first conductivity type that is shared in common with a drain region of the first conductivity type of the selection transistors. The selection transistors of a same column of the memory array have a common drain region, a common source region, and a common channel region.
1. A memory array, comprising:
a plurality of memory cells of Z 2 -FET type; and
a corresponding plurality of MOS-type selection transistors;
wherein each memory cell comprises a first region of a first conductivity type in common with a drain region of the first conductivity type of a corresponding one of the MOS-type selection transistors; and
wherein the MOS-type selection transistors of a same column of the memory array have a common drain region, a common source region, and a common channel region.
2. The memory array of claim 1 , wherein the memory cells of a same column of the memory array have a common front gate.
3. The memory array of claim 2 , wherein the common front gate of the memory cells of the same column is connected to a word line.
4. The memory array of claim 1 , wherein each memory cell comprises a second region of a second conductivity type.
5. The memory array of claim 4 , wherein the second regions of the memory cells of a same row of the memory array are connected to a bit line.
6. The memory array of claim 5 , wherein the memory cells of the same row of the memory array are connected two by two and have a second common region.
7. The memory array of claim 1 , wherein the common source region is connected to a reference voltage.
8. The memory array of claim 1 , wherein the MOS-type selection transistors of a same column have a common gate.
9. The memory array of claim 8 , wherein the common gate region of the MOS-type selection transistors of a same column of the memory array is connected to a control line.
10. The memory array of claim 1 , wherein the MOS-type selection transistors are N-channel MOS transistors.
11. The memory array of claim 1 , wherein the MOS-type selection transistors are P-channel MOS transistors.
12. The memory array of claim 1 , wherein each memory cell of Z 2 -FET type comprises, on a substrate:
an anode region;
a cathode region;
a lightly-doped region separating the anode region from the cathode region; and
an insulated gate region positioned on top of and in contact with a portion of the lightly-doped region.
13. The memory array of claim 12 , wherein the cathode region is the first region and wherein a width of the anode region and lightly-doped region is smaller than a width of the first region, said widths being perpendicular to a direction extending between the drain region and source region of the MOS-type selection transistor.
14. The memory array of claim 12 , wherein the anode region is the first region and wherein a width of the cathode region and lightly-doped region is smaller than a width of the first region, said widths being perpendicular to a direction extending between the drain region and source region of the MOS-type selection transistor.
15. A memory cell, comprising:
a Z 2 -FET type memory device including an anode region, a cathode region and a lightly-doped region separating the anode region from the cathode region; and
a MOS-type selection transistor connected to the Z 2 -FET type memory device;
wherein the cathode region of the Z 2 -FET type memory device is also a drain region of the MOS-type selection transistor; and
wherein a width of the anode region and the lightly-doped region is smaller than a width of the cathode region, said widths being perpendicular to a direction extending between the drain region and a source region of the MOS-type selection transistor.
16. The memory cell of claim 15 , wherein a front gate of the Z 2 -FET type memory device is connected to a word line.
17. The memory cell of claim 15 , wherein the anode region of the Z 2 -FET type memory device is connected to a bit line.
18. The memory cell of claim 15 , wherein the source region is connected to a reference voltage.
19. A memory cell, comprising:
a Z 2 -FET type memory device including an anode region, a cathode region and a lightly-doped region separating the anode region from the cathode region; and
a MOS-type selection transistor connected to the Z 2 -FET type memory device;
wherein the anode region of the Z 2 -FET type memory device is also a drain region of the MOS-type selection transistor; and
wherein a width of the cathode region and lightly-doped region is smaller than a width of the anode region, said widths being perpendicular to a direction extending between the drain region and source region of the MOS-type selection transistor.
20. The memory cell of claim 19 , wherein a front gate of the Z 2 -FET type memory device is connected to a word line.
21. The memory cell of claim 19 , wherein the anode region of the Z 2 -FET type memory device is connected to a bit line.
22. The memory cell of claim 19 , wherein the source region is connected to a reference voltage.
23. A method of manufacturing a memory array, comprising:
forming a plurality of memory cells of Z 2 -FET type and a plurality of MOS-type selection transistors arranged in rows and in columns, comprising:
forming each memory cell to include a first region of a first conductivity type;
forming each MOS-type selection transistor to include a drain region in common with the first region of the memory cell and with all selection transistors of a same column;
forming a source region common to all the MOS-type selection transistors of the same column; and
forming a gate region common to all the MOS-type selection transistors of the same column.