Memory including blocking dielectric in etch stop tier
View Patent ↗Vertical memories and methods of making the same are discussed generally herein. In one embodiment, a vertical memory can include a vertical pillar extending to a source, an etch stop tier over the source, and a stack of alternating dielectric tiers and conductive tiers over the etch stop tier. The etch stop tier can comprise a blocking dielectric adjacent to the pillar. In another embodiment, the etch stop tier can comprise a blocking dielectric adjacent to the pillar, and a plurality of dielectric films horizontally extending from the blocking dielectric into the etch stop tier.
1. A memory comprising:
a vertical pillar coupled to a source; and
a dielectric etch stop tier over the source, the dielectric etch stop tier comprising a blocking dielectric adjacent to the pillar, and a plurality of dielectric films horizontally extending from the blocking dielectric into the dielectric etch stop tier and separating the dielectric etch stop tier into multiple dielectric tiers.
2. The memory of claim 1 , wherein the pillar comprises polysilicon.
3. The memory of claim 1 , wherein the pillar comprises a sidewall, and wherein the sidewall comprises silicon oxide.
4. The memory of claim 1 , wherein the etch stop tier comprises aluminum oxide (ALOX).
5. The memory of claim 1 , wherein the blocking dielectric comprises silicon oxide.
6. The memory of claim 1 , wherein the plurality of dielectric films comprise silicon oxide.
7. The memory of claim 1 , further comprising a stack of alternating dielectric tiers and conductive tiers over the dielectric etch stop tier.
8. The memory of claim 7 , wherein at least one of the conductive tiers includes a control gate, a charge storage structure adjacent to the pillar, and a barrier film between the control gate and the charge storage structure.
9. The memory of claim 8 , wherein the control gate and the charge storage structure comprise polysilicon.
10. The memory of claim 8 , wherein the barrier film comprises oxide-nitride-oxide (ONO).
11. A memory comprising:
a dielectric etch stop tier over a source, wherein the etch stop tier comprises:
a blocking dielectric adjacent to a pillar that vertically extends to the source; and
a plurality of dielectric films that horizontally extend from the blocking dielectric into the dielectric etch stop tier and separate the dielectric etch stop tier into multiple dielectric tiers.
12. The memory of claim 11 , further comprising a stack of alternating dielectric tiers and conductive tiers over the dielectric etch stop tier, wherein at least one of the conductive tiers includes a control gate, and a charge storage structure adjacent to the pillar.
13. The memory of claim 12 , wherein the conductive tier further comprises a barrier film between the control gate and the charge storage structure.
14. The memory of claim 13 , wherein e charge storage structure comprises a floating gate.
15. The memory of claim 11 , further comprising a select gate source (SGS) between the etch stop tier and the source, wherein the select gate source tier comprises polysilicon.
16. The memory of claim 15 , further comprising a separation tier between the source and the select gate source.
17. The memory of claim 16 , wherein the separation tier comprises silicon oxide.