IP Library Granted Patent US 7,898,006
Granted Patent B2
US 7,898,006 · App. 11/940,704 · Granted Mar 1, 2011

Integrated circuit having memory cells and method of manufacture

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,898,006
App. No.
11/940,704
Granted
Mar 1, 2011
Kind
B2
Abstract

An integrated circuit having memory cells and a method of manufacture is disclosed. One embodiment provides a switching active volume and a selection transistor coupled in series between a first electrode and a second electrode. The selection transistor is a vertical transistor for at least partially guiding a substantially vertical current flow. The second electrode includes a buried diffused ground plate formed in a substrate. A metal-containing region at least partially contacting the buried diffused ground plate is provided, the metal-containing region at least extending below the selection transistor.

Claims (58)

1. An integrated circuit having a memory cell, comprising:

a switching active volume and a selection transistor coupled in series between a first electrode and a second electrode;

wherein the selection transistor is a vertical transistor for at least partially guiding a substantially vertical current flow;

wherein the second electrode comprises a buried diffused ground plate formed in a substrate; and

a metal-containing region at least partially directly contacting the buried diffused ground plate, the metal-containing region at least extending below the selection transistor.

2. The integrated circuit of claim 1 , wherein the first electrode is a bitline electrode.

3. The integrated circuit of claim 1 , wherein the second electrode is a ground electrode.

4. The integrated circuit of claim 1 , wherein the metal-containing region is located below an isolation region.

5. The integrated circuit of claim 4 , wherein the isolation region comprises an isolation trench.

6. The integrated circuit of claim 4 , wherein the isolation region comprises at least parts of at least one of a gate electrode and a word line.

7. The integrated circuit of claim 1 , wherein the metal-containing region is at least partially embedded within the buried diffused ground plate.

8. The integrated circuit of claim 7 , wherein the metal-containing region is completely embedded within the buried diffused ground plate.

9. The integrated circuit of claim 7 , wherein the metal-containing region is partially embedded within the buried diffused ground plate and partially embedded within a non-diffused part of the substrate.

10. The integrated circuit of claim 1 , wherein the selection transistor is one of a double gate transistor, a surrounding gate transistor or a bipolar junction transistor.

11. The integrated circuit of claim 1 , wherein the substrate comprises a silicon substrate.

12. The integrated circuit of claim 11 , wherein the substrate comprises doped silicon.

13. The integrated circuit of claim 1 , wherein the substrate comprises a SOI substrate.

14. The integrated circuit of claim 13 , wherein the metal-containing region is located at least partially below the ground plate.

15. The integrated circuit of claim 10 , wherein the selection transistor is a bipolar junction transistor, comprising a metal wiring in a collector plate electrode.

16. An integrated circuit comprising an array of multiple memory cells, each memory cell comprising:

a switching active volume and a selection transistor connected in series between a first electrode and a second electrode;

wherein the selection transistor is a vertical transistor for at least partially guiding a substantially vertical current flow;

wherein the second electrode comprises a buried diffused ground plate formed in a substrate; and

wherein the integrated circuit further comprises a metal-containing region at least partially directly contacting the buried diffused ground plate, and the second electrode being common to the memory cells of the array.

17. The integrated circuit of claim 16 , the metal-containing region at least extending below the selection transistors of the memory cells of the array.

18. The integrated circuit of claim 16 , wherein the metal-containing region comprises a metal-containing wiring.

19. The integrated circuit of claim 18 , wherein the metal-containing wiring is continuous at least in one direction.

20. The integrated circuit of claim 16 , wherein the metal-containing region is located below an isolation region that separates active regions of adjacent memory cells.

21. The integrated circuit of claim 20 , wherein the isolation region comprises at least one isolation trench.

22. The integrated circuit of claim 20 , wherein the isolation region comprises at least parts of at least one of a gate electrode and a word line.

23. The integrated circuit of claim 16 , the metal-containing region being at least partially embedded within the buried diffused ground plate.

24. The integrated circuit of claim 16 , wherein the selection transistor is one of a doubled gate transistor, a single gate transistor and a bipolar junction transistor.

25. The integrated circuit of claim 16 , wherein the substrate is one of a silicon substrate and a SOI substrate.

26. The integrated circuit of claim 1 , wherein the switching active volume is positioned on a first side of the selection transistor and the metal-containing region is positioned on a second side of the selection transistor opposite the first side.

27. The integrated circuit of claim 16 , wherein the switching active volume is positioned on a first side of the selection transistor and the metal-containing region is positioned on a second side of the selection transistor opposite the first side.

28. An integrated circuit comprising:

a vertical selection transistor;

a switching active volume coupled to a first side of the selection transistor;

a buried diffused ground plate coupled to a second side of the selection transistor opposite the first side; and

a metal-containing region directly contacting the buried diffused ground plate, the metal-containing region positioned on the second side of the selection transistor.

29. The integrated circuit of claim 28 , further comprising:

shallow trench isolation reaching to the buried diffused ground plate.

30. The integrated circuit of claim 29 , wherein the metal-containing region directly contacts the shallow trench isolation.

31. The integrated circuit of claim 28 , wherein the metal-containing region comprises one of W and TiN.

32. The integrated circuit of claim 28 , further comprising:

a bit line coupled to the switching active volume.

33. The integrated circuit of claim 32 , further comprising:

a word line coupled to a gate of the selection transistor.

34. The integrated circuit of claim 33 , wherein the bit line is perpendicular to the word line.

35. The integrated circuit of claim 28 , further comprising:

a contact coupling the selection transistor to the switching active volume.

36. The integrated circuit of claim 28 , wherein the selection transistor comprises a double gate transistor.

37. The integrated circuit of claim 28 , wherein the selection transistor comprises a surrounding gate transistor.

38. The integrated circuit of claim 28 , wherein the selection transistor comprises a gate electrode that serves as a gate electrode for another adjacent selection transistor.

39. The integrated circuit of claim 38 , further comprising:

poly silicon coupling the gate electrode to a word line.

40. The integrated circuit of claim 28 , wherein the switching active volume comprises resistively switching material.

41. The integrated circuit of claim 28 , wherein the switching active volume comprises phase change material.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 9, 2015
From: INFINEON TECHNOLOGIES AG
To: POLARIS INNOVATIONS LIMITED
Reel/Frame 037254/0782 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 8, 2015
From: QIMONDA AG
To: INFINEON TECHNOLOGIES AG
Reel/Frame 035623/0001 →