Dopant-modulated etching for memory devices
AssigneeMicron Technology, Inc.
InventorsInnocenzo Tortorelli, Mattia Robustelli
Life of this patent
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Abstract
Methods and devices based on the use of dopant-modulated etching are described. During fabrication, a memory storage element of a memory cell may be non-uniformly doped with a dopant that affects a subsequent etching rate of the memory storage element. After etching, the memory storage element may have an asymmetric geometry or taper profile corresponding to the non-uniform doping concentration. A multi-deck memory device may also be formed using dopant-modulated etching. Memory storage elements on different memory decks may have different taper profiles and different doping gradients.
Claims25
A memory device, comprising:
- a first access line;
- a second access line;
- a memory cell coupled with the first access line and the second access line, the memory cell comprising a memory storage element that is doped with a dopant, the memory storage element having a concentration of the dopant that monotonically decreases or increases in a first direction between the first access line and the second access line, the memory storage element having an etched taper caused at least in part by a variation of the concentration of the dopant in the memory storage element.
A memory device, comprising:
- a first deck of memory cells comprising:
- a first access line;
- a second access line;
- and
- a first memory cell having a first bottom surface coupled with the first access line and having a first top surface opposite the first bottom surface, the first top surface coupled with the second access line, the first memory cell having a first doping gradient of a dopant and a first taper profile that is an etched taper caused at least in part by the first doping gradient;
- and
- a second deck of memory cells, comprising:
- a third access line;
- a fourth access line;
- and
- a second memory cell having a second bottom surface coupled with the fourth access line and a second top surface opposite the second bottom surface, the second top surface coupled with the third access line, the second memory cell having a second doping gradient of the dopant and a second taper profile corresponding to the second doping gradient.
A memory device, comprising:
- a first deck of memory cells comprising:
- a first access line;
- a second access line;
- and
- a first memory cell having a first bottom surface coupled with the first access line and a first top surface opposite the first bottom surface, the first top surface coupled with the second access line, the first memory cell being doped with a dopant and having a first taper profile between the first bottom surface and the first top surface, the first taper profile being an etched profile caused at least in part by a variation in a concentration of the dopant in the first memory cell;
- and
- a second deck of memory cells, comprising:
- a third access line;
- a fourth access line;
- and
- a second memory cell having a second bottom surface coupled with the fourth access line and a second top surface opposite the second bottom surface, the second top surface coupled with the third access line, the second memory cell having a second taper profile different than the first taper profile between the second bottom surface and the second top surface.
Dependencies are inferred from the claim text.