Circuit-protection devices

• US 10,679,982 B2
• Filed: 08/22/2018
• Issued: 06/09/2020
• Est. Priority Date: 08/28/2017
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Smith, Michael
• Primary Examiner(s): Norman, James G
• Application Number:
  US16/108,413
• Publication Number:
  US 20190067271A1
• Time in Patent Office: 657 Days
• Field of Search: None
• CPC Class Codes: G11C 16/04 using variable threshold transistors, e.g. FAMOS
• CPC Class Codes: G11C 16/0483 comprising cells having several storage transistors connected in series
• CPC Class Codes: G11C 16/08 Address circuits; Decoders; Word-line control circuits
• CPC Class Codes: G11C 16/16 for erasing blocks, e.g. arrays, words, groups
• CPC Class Codes: G11C 16/22 Safety or protection circuits preventing unauthorised or accidental access to memory cells
• CPC Class Codes: G11C 7/02 with means for avoiding parasitic signals
• CPC Class Codes: H01L 27/0266 using field effect transistors as protective elements

Abstract

Circuit-protection devices may include first and second circuit-protection units, a first gate having a first source/drain connected to a first node of the first circuit-protection unit, and a second gate having a first source/drain connected to a first node of the second circuit-protection unit, wherein a second source/drain of the first gate is connected to a second source/drain of the second gate.

Claims

1. A circuit-protection device, comprising:

first and second circuit-protection units, each comprising a first node and a second node;

a first gate having a first source/drain electrically connected to the first node of the first circuit-protection unit; and

a second gate having a first source/drain electrically connected to the first node of the second circuit-protection unit;

wherein a second source/drain of the first gate is electrically connected to a second source/drain of the second gate;

wherein the first node of the first circuit-protection unit is laterally between the second node of the first circuit-protection unit and the first node of the second circuit-protection unit; and

wherein the first node of the second circuit-protection unit is laterally between the second node of the second circuit-protection unit and the first node of the first circuit-protection unit.

2. The circuit-protection device of claim 1, further comprising a contact electrically connected to the first source/drain of the first gate, a contact electrically connected to the first source/drain of the second gate, and a contact electrically connected to the second source/drains of the first gate and of the second gate.

3. The circuit-protection device of claim 2, wherein the first and second source/drains of the first gate and the second gate each comprise regions having higher conductivity levels than their respective first or second source/drains, and wherein the regions are each electrically connected to their respective contact.

4. The circuit-protection device of claim 2, further comprising a contact electrically connected to the second node of each of the first and second circuit-protection units.

5. The circuit-protection device of claim 4, wherein the second node of each of the first and second circuit-protection units each comprise a region having higher conductivity levels than their respective second node, and wherein the regions of the second nodes are each electrically connected to their respective contact.

6. A circuit-protection device, comprising:

a plurality of first circuit-protection units, each comprising a first node and a second node;

a plurality of second circuit-protection units, each comprising a first node and a second node;

a first gate having a plurality of first source/drains, each first source/drain of the plurality of first source/drains of the first gate directly electrically connected to a first node of a respective first circuit-protection unit of the plurality of first circuit-protection units; and

a second gate having a plurality of first source/drains, each first source/drain of the plurality of first source/drains of the second gate directly electrically connected to a first node of a respective second circuit-protection unit of the plurality of second circuit-protection units;

wherein a second source/drain of the first gate is directly electrically connected to a second source/drain of the second gate;

wherein the first nodes of a subset of first circuit-protection units of the plurality of first circuit-protection units are on a common active region; and

wherein the first nodes of a subset of second circuit-protection units of the plurality of second circuit-protection units are on the common active region.

7. The circuit-protection device of claim 6, wherein the first gate is configured to selectively electrically isolate the first nodes of each first circuit-protection unit of the plurality of first circuit-protection units from each other, and wherein the second gate is configured to selectively electrically isolate the first nodes of each second circuit-protection unit of the plurality of second circuit-protection units from each other.

8. The circuit-protection device of claim 7, wherein the first gate is further configured to selectively electrically connect the first nodes of each first circuit-protection unit of the plurality of first circuit-protection units to each other, and wherein the second gate is further configured to selectively electrically connect the first nodes of each second circuit-protection unit of the plurality of second circuit-protection units to each other.

9. The circuit-protection device of claim 6, wherein the subset of first circuit-protection units comprises each first circuit-protection unit of the plurality of first circuit-protection units, and wherein the subset of second circuit-protection units comprises each second circuit-protection unit of the plurality of second circuit-protection units.

10. The circuit-protection device of claim 6, wherein the subset of first circuit-protection units is a first subset of first circuit-protection units, the subset of second circuit-protection units is a first subset of second circuit-protection units, and the common active region is a first common active region, and further comprising:

wherein the first nodes of a second subset of first circuit-protection units of the plurality of first circuit-protection units are on a second common active region;

wherein the first nodes of a second subset of second circuit-protection units of the plurality of second circuit-protection units are on the second common active region;

wherein the second common active region is isolated from the first common active region;

wherein the second subset of first circuit-protection units is mutually exclusive of the first subset of first circuit-protection units; and

wherein the second subset of second circuit-protection units is mutually exclusive of the first subset of second circuit-protection units.

11. The circuit-protection device of claim 6, wherein a particular active region extending from the common active region to the second node of a particular first circuit-protection unit of the subset of first circuit-protection units varies in width from the common active region to the second node of the particular first circuit-protection unit.

12. The circuit-protection device of claim 11, wherein the width of the particular active region is wider at the second node of the particular first circuit-protection unit than at a point of interface with the common active region.

13. The circuit-protection device of claim 12, wherein the width of the particular active region is wider at a point between the second node of the particular first circuit-protection unit and the point of interface with the common active region than at the second node of the particular first circuit-protection unit or at the point of interface with the common active region.

14. The circuit-protection device of claim 6, wherein the second source/drain of the first gate and the second source/drain of the second gate are commonly electrically connected to a source of an array of memory cells.

15. The circuit-protection device of claim 6, further comprising a contact electrically connected to each first source/drain of the plurality of first source/drains of the first gate, a contact electrically connected to each first source/drain of the plurality of first source/drains of the second gate, and a contact electrically connected to the second source/drain of the first gate and to the second source/drain of the second gate.

16. The circuit-protection device of claim 15, further comprising a contact electrically connected to the second source/drain of the first gate and to the second source/drain of the second gate for each contact electrically connected to a first source/drain of the plurality of first source/drains of the first gate.

17. The circuit-protection device of claim 16, wherein the contact electrically connected to the second source/drain of the first gate and to the second source/drain of the second gate for a particular contact electrically connected to a first source/drain of the plurality of first source/drains of the first gate is formed between the particular contact electrically connected to a first source/drain of the plurality of first source/drains of the first gate and a corresponding contact electrically connected to a first source/drain of the plurality of first source/drains of the second gate.

18. The circuit-protection device of claim 6, further comprising an isolation region between a pair of adjacent second nodes of the plurality of first circuit-protection units.

19. The circuit-protection device of claim 18, further comprising an isolation region between a pair of adjacent second nodes of the plurality of second circuit-protection units.

20. The circuit-protection device of claim 19, further comprising a respective isolation region between each pair of adjacent second nodes of the plurality of first circuit-protection units and a respective isolation region between each pair of adjacent second nodes of the plurality of second circuit-protection units.

21. The circuit-protection device of claim 6, wherein the first gate and the second gate are coupled to different control lines.

22. The circuit-protection device of claim 21, wherein the different control lines extend beyond an end of a particular active region that is not between the first node and the second node of any circuit-protection unit of the plurality of first circuit-protection units or the plurality of second circuit-protection units.

23. The circuit-protection device of claim 22, wherein a width of each of the different control lines is wider at the end of the particular active region than a width of each of the different control lines between the first node of one of the first circuit-protection units of the plurality of first circuit-protection units and a corresponding first node of one of the second circuit-protection units of the plurality of second circuit-protection units.

24. The circuit-protection device of claim 21, wherein the different control lines are electrically connected.

25. The circuit-protection device of claim 21, wherein the different control lines comprise an electrical connection formed at an end of a particular active region that is not between the first node and the second node of any circuit-protection unit of the plurality of first circuit-protection units or the plurality of second circuit-protection units.

26. The circuit-protection device of claim 25, wherein a width of the electrical connection is wider than a width of each of the different control lines plus a distance between the different control lines at the electrical connection.

27. The circuit-protection device of claim 25, wherein an inner corner of the electrical connection between the different control lines is rounded.

28. The circuit-protection device of claim 25, wherein the electrical connection extends beyond the end of the particular active region.

29. The circuit-protection device of claim 28, wherein the electrical connection extends beyond the end of the particular active region in more than one direction.

30. The circuit-protection device of claim 6, wherein each first node of the plurality of first circuit-protection units is electrically connected to a respective data line of an array of memory cells.

31. The circuit-protection device of claim 30, wherein each first node of the plurality of second circuit-protection units is electrically connected to a respective data line of the array of memory cells.

32. The circuit-protection device of claim 31, wherein each second node of the plurality of first circuit-protection units is electrically connected to peripheral circuitry outside of the array of memory cells.

33. The circuit-protection device of claim 32, wherein the peripheral circuitry comprises circuitry selected from a group consisting of a data cache and a data register.

34. The circuit-protection device of claim 6, wherein for each first circuit-protection unit of the plurality of first circuit-protection units, and for each second circuit-protection unit of the plurality of second circuit-protection units, the first gate and the second gate comprise field-effect transistors.