Dual-trench isolated crosspoint memory array and method for fabricating same
US6875651B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 2003 |
| Grant date | Apr 5, 2005 |
| Priority date | — |
| Expiry date | Jul 31, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2213/77
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory array dual-trench isolation structure and a method for forming the same have been provided. The method comprises: forming a p-doped silicon (p-Si) substrate; forming an n-doped (n+) Si layer overlying the p-Si substrate; prior to forming the n+ Si bit lines, forming a p+ Si layer overlying the n+ Si layer; forming a layer of silicon nitride overlying the p+ layer; forming a top oxide layer overlying the silicon nitride layer; performing a first selective etch of the top oxide layer, the silicon nitride layer, the p+ Si layer, and a portion of the n+ Si layer, to form n+ Si bit lines and bit line trenches between the bit lines; forming an array of metal bottom electrodes overlying a plurality of n-doped silicon (n+ Si) bit lines, with intervening p-doped (p+) Si areas; forming a plurality of word line oxide isolation structures orthogonal to and overlying the n+ Si bit lines, adjacent to the bottom electrodes, and separating the p+ Si areas; forming a plurality of top electrode word lines, orthogonal to the n+ Si bit lines, with an interposing memory resistor material overlying the bottom electrodes; and, forming oxide-filled word line trenches adjacent the word lines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.