Arrays of elevationally-extending strings of memory cells and methods used in forming an array of elevationally-extending strings of memory cells
US11037797B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 2020 |
| Grant date | Jun 15, 2021 |
| Priority date | — |
| Expiry date | Apr 21, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B43/27
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method used in forming an array of elevationally-extending strings of memory cells comprises forming a stack comprising vertically-alternating insulative tiers and wordline tiers. The stack comprises an etch-stop tier between a first tier and a second tier of the stack. The etch-stop tier is of different composition from those of the insulative tiers and the wordline tiers. Etching is conducted into the insulative tiers and the wordline tiers that are above the etch-stop tier to the etch-stop tier to form channel openings that have individual bases comprising the etch-stop tier. The etch-stop tier is penetrated through to extend individual of the channel openings there-through. After extending the individual channel openings through the etch-stop tier, etching is conducted into and through the insulative tiers and the wordline tiers that are below the etch-stop tier to extend the individual channel openings deeper into the stack below the etch-stop tier. Transistor channel material is formed in the individual channel openings elevationally along the etch-stop tier and along the insulative tiers and the wordline tiers that are above and below the etch-stop tier. Arrays independent…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.