Conductive structures, systems and devices including conductive structures and related methods

Patent metadata

Field	Value
Publication number	US-9941209-B2
Application number	US-201615068329-A
Country	US
Kind code	B2
Filing date	Mar 11, 2016
Priority date	Mar 11, 2016
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

Conductive structures include stair step structures positioned along a length of the conductive structure and at least one landing comprising at least one via extending through the conductive structure. The at least one landing is positioned between a first stair step structure of the stair step structures and a second stair step structure of the stair step structures. Devices may include such conductive structures. Systems may include a semiconductor device and stair step structures separated by at least one landing having at least one via formed in the at least one landing. Methods of forming conductive structures include forming at least one via through a landing positioned between stair step structures.

First claim

What is claimed is:

1. A conductive structure, comprising:
stair step structures positioned along a length of the conductive structure, each stair step structure comprising at least two conductive steps, each conductive step of the at least two conductive steps being at least partially separated from an adjacent conductive step of the at least two conductive steps by insulative material;
at least one landing comprising at least one via extending through the conductive structure underlying and defining the at least one landing, the at least one landing positioned between a first stair step structure of the stair step structures and a second stair step structure of the stair step structures positioned adjacent to the first stair step structure; and
access lines, each access line in communication with a conductive portion of one conductive step of the at least two conductive steps of the stair step structures and extending from the one conductive step to, and being in communication with, the at least one via extending through the conductive structure underlying and defining the at least one landing.

2. The conductive structure of claim 1 , wherein the at least one via comprises a plurality of vias, and wherein each access line extends from a conductive portion of one conductive step of at least two conductive steps of the stair step structures to one via of the plurality of vias.

3. The conductive structure of claim 1 , further comprising at least one pair of additional stair step structures and at least one additional landing, each additional stair step structure of the at least one pair of additional stair step structures opposing another stair step structure of the at least one pair with the at least one additional landing therebetween.

4. The conductive structure of claim 1 , wherein at least one of the stair step structures lacks access lines connected to conductive steps of the at least one stair step structure.

5. The conductive structure of claim 1 , wherein the at least one landing comprises a plurality of landings, each landing of the plurality of landings being positioned between a pair of the stair step structures.

6. The conductive structure of claim 1 , wherein the at least one landing is defined by a stack of alternating first material and second material, wherein the first material and the second material each comprise an insulative material.

7. The conductive structure of claim 1 , wherein the at least one landing is defined by a stack of alternating first material and second material, wherein the first material comprises a conductive material and the second material comprises an insulative material.

8. The conductive structure of claim 7 , further comprising an insulative liner at least partially surrounding the at least one via and insulating the at least one via from the conductive material of the at least one landing.

9. The conductive structure of claim 1 , wherein the at least one via is operably coupled to at least one control unit underlying the stair step structures and the at least one landing.

10. The conductive structure of claim 1 , wherein at least some of the stair step structures each comprise a word line plate structure.

11. The conductive structure of claim 1 , wherein one stair step structure of the stair step structures comprises a drain select gate (SGD) structure.

12. The conductive structure of claim 1 , further comprising stack slot elements extending along a length of the conductive structure.

13. The conductive structure of claim 12 , wherein the stack slot elements comprise:
outer stack slot elements extending continuously along a majority of the length of the conductive structure; and
inner stack slot elements extending discontinuously along the length of the conductive structure.

14. The conductive structure of claim 13 , wherein the inner stack slot elements are positioned proximate the stair step structures.

15. The conductive structure of claim 14 , wherein the at least one landing lacks the inner stack slot elements.

16. The conductive structure of claim 13 , wherein the stack slot elements comprise an insulative material positioned over a conductive material deposited in a replacement gate process.

17. A method of forming the conductive structure of claim 1 , the method comprising:
forming openings through a stack of material at the at least one landing of the conductive structure defined between two of the stair step structures, the two stair step structures being positioned on one side of and in electrical communication with a semiconductor device;
forming contacts in the openings in the stack of the material; and
electrically coupling a conductive portion of at least one step of the stair step structure with at least one contact of the contacts.

18. The method of claim 17 , further comprising forming the stack of material with alternating insulative and conductive materials.

19. The method of claim 18 , further comprising forming a liner in each opening of the openings to surround a contact therein.

20. The method of claim 17 , further comprising forming the stack of material with alternating insulative materials comprising a first insulative material and a second sacrificial insulative material.

21. The method of claim 20 , further comprising:
forming an opening through the stack of material;
removing a portion of the second sacrificial insulative material adjacent the opening in a volume of the second sacrificial material underlying the first insulative material; and
depositing a conductive material in the opening and in the volume from which the portion of the second sacrificial material is removed to form the conductive portion of at least one step of the stair step structure.

22. The method of claim 21 , further comprising:
removing a portion of the conductive material within the opening; and
depositing another insulative material within the opening.

23. The method of claim 22 , further comprising forming an electrical connection between the conductive portion of at least one step of the stair step structure and another, adjacent conductive portion of the at least one step around the another insulative material.

24. The method of claim 17 , further comprising performing a replacement gate process on at least one stair step structure of the stair step structures while masking the landing of the conductive structure.

25. A conductive structure, comprising:
tiered structures positioned along a length of the conductive structure, each tiered structure comprising at least two tiers having a conductive portion, each conductive portion of the at least two tiers being at least partially separated from an adjacent conductive portion of the at least two tiers by insulative material; and
a landing comprising vias extending through the conductive structure at the landing, the landing and the vias positioned between a first tiered structure of the tiered structures and a second tiered structure of the tiered structures positioned adjacent to the first tiered structure.

26. The conductive structure of claim 25 , further comprising access lines coupling conductive portions of the at least two tiers of the tiered structures to a respective via of the vias.

27. The conductive structure of claim 25 , further comprising stack slot elements extending along the length of the conductive structure, wherein at least one stack slot el

Assignees

• Micron Technology Inc

Inventors

• Tessariol Paolo
• Wolstenholme Graham R
• Yip Aaron

Classifications

• H10W20/089

  using processes for implementing desired shapes or dispositions of the openings, e.g. double patterning · CPC title

• H10W20/056

  by filling conductive material into holes, grooves or trenches · CPC title

• H10W20/42

  Vias, e.g. via plugs · CPC title

• H10W20/435 Primary

  Cross-sectional shapes or dispositions of interconnections · CPC title

• H01L27/11517

  Electricity · mapped topic