Manufacturing methods of JFET-type compact three-dimensional memory
Manufacturing methods of JFET-type compact three-dimensional memory (3D-M C ) are disclosed. In a memory level stacked above the substrate, an x-line extends from a memory array to an above-substrate decoding stage. A JFET-type transistor is formed on the x-line as a decoding device for the above-substrate decoding stage, where the overlap portion of the x-line with the control-line (c-line) is semi-conductive.
1. A manufacturing method of a JFET-type compact three-dimensional memory (3D-Mc) including a decoding device and a memory device on a memory level above a semiconductor substrate, comprising the steps of:
1) forming a bottom electrode comprising a heavily-doped semiconductor material and a memory layer on said memory level;
2) applying a photo-resist layer and forming a hole therein at the location of said decoding device;
3) etching said memory layer under said hole; performing an ion-implant step to counter-dope said heavily-doped semiconductor material under said hole to a lightly-doped semiconductor material, then removing said photo-resist layer;
4) etching said memory layer and said bottom electrode to define at least a x-line;
5) depositing and etching a high-conductive material to define at least a y-line and a control-line (c-line);
wherein said memory device is formed at the intersection of said x-line and said y-line, and said decoding device is formed at the intersection of said x-line and said c-line.
2. The method according to claim 1 , wherein the overlap portion and the non-overlap portions of said x-line with said y-line are both highly-conductive.
3. The method according to claim 1 , wherein said memory device is a two-terminal device.
4. The method according to claim 1 , wherein
the overlap portion of said x-line with said c-line is semi-conductive; and,
the non-overlap portions of said x-line with said c-line are highly-conductive.
5. The method according to claim 1 , wherein said decoding device is a three-terminal device.
6. The method according to claim 1 , wherein said decoding device comprises a pass-transistor.
7. A manufacturing method of a JFET-type compact three-dimensional memory (3D-Mc) including a decoding device and a memory device on a memory level above a semiconductor substrate, comprising the steps of:
1) forming a bottom electrode and a memory layer on said memory level, said bottom electrode comprising an upper highly-conductive sub-layer and a lower semi-conductive sub-layer;
2) applying a photo-resist layer and forming a hole therein at the location of said decoding device;
3) etching said memory layer and said upper highly-conductive sub-layer up to said lower semi-conductive sub-layer under said hole, then removing said photo-resist layer;
4) etching said memory layer and said bottom electrode to define at least a x-line;
5) depositing and etching a highly-conductive material to define at least a y-line and a control-line (c-line);
wherein said memory device is formed at the intersection of said x-line and said y-line, and said decoding device is formed at the intersection of said x-line and said c-line.
8. The method according to claim 7 , wherein the overlap portion and the non-overlap portions of said x-line with said y-line are both highly-conductive.
9. The method according to claim 7 , wherein the bottom electrode of said memory device comprises both said upper highly-conductive sub-layer and said lower semi-conductive sub-layer.
10. The method according to claim 7 , wherein said memory device is a two-terminal device.
11. The method according to claim 7 , wherein the overlap portion of said x-line with said c-line is semi-conductive; and, the non-overlap portions of said x-line with said c-line are highly-conductive.
12. The method according to claim 1 , wherein said decoding device is a three-terminal device.
13. The method according to claim 1 , wherein said decoding device comprises a pass-transistor.
14. The method according to claim 7 , wherein the bottom electrode of said decoding device comprises only said lower semi-conductive sub-layer.
15. A manufacturing method of a JFET-type compact three-dimensional memory (3D-M C ) including a decoding device and a memory device on a memory level above a semiconductor substrate, comprising the steps of:
1) forming a bottom electrode comprising a metallic material and a memory layer on said memory level;
2) applying a photo-resist layer and forming a hole therein at the location of said decoding device;
3) etching said memory layer and said highly-conductive material under said hole;
removing said photo-resist layer; and, filling said hole with a semi-conductive material;
4) etching said memory layer and said bottom electrode to define at least a x-line;
5) depositing and etching a high-conductive material to define at least a y-line and a control-line (c-line);
wherein said memory device is formed at the intersection of said x-line and said y-line, and said decoding device is formed at the intersection of said x-line and said c-line.
16. The method according to claim 15 , wherein the overlap portion and the non-overlap portions of said x-line with said y-line are both highly-conductive.
17. The method according to claim 15 , wherein said memory device is a two-terminal device.
18. The method according to claim 15 , wherein
the overlap portion of said x-line with said c-line is semi-conductive; and,
the non-overlap portions of said x-line with said c-line are highly-conductive.
19. The method according to claim 15 , wherein said decoding device is a three-terminal device.
20. The method according to claim 15 , wherein said decoding device comprises a pass-transistor.