Oxygen barrier for cell container process
AssigneeMicron Technology, Inc.
InventorsSam Yang, Lingyi A. Zheng
Life of this patent
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Abstract
A memory cell container of a DRAM semiconductor memory device and method for manufacturing the cell container are disclosed. The cell includes a container formed in a structural layer such as borophosphosilicate glass. The container is then lined with a polysilicon such as hemispherical grained polysilicon. A dielectric layer is deposited over the polysilicon layer. A barrier layer is deposited over the dielectric layer such that the opening of the container is covered but not the sidewalls or the bottom of the container. The cell is then oxidized and the barrier layer provides protection as an oxygen barrier during the oxidation or any following re-oxidation process.
Claims23
A method of forming a cell container for a memory device comprising:
- providing a structural layer;
- forming a cavity in the structural layer having a bottom and at least one sidewall extending to an opening at a surface of the structural layer;
- depositing a polysilicon layer over the bottom and the at least one sidewall of the cavity;
- depositing a nitride layer over the polysilicon layer and at least a portion of the surface of the structural layer including an area surrounding the opening of the cavity;
- and
- depositing a barrier layer over a portion of the nitride layer including the area surrounding the opening of the cavity and a portion of the at least one sidewall adjacent the opening.
A method of forming a cell container for a memory device comprising:
- providing a structural layer of borophosphosilicate glass;
- forming a cavity in the structural layer having a bottom and at least one sidewall extending to an opening at a surface of the structural layer;
- depositing a hemispherical grained polysilicon layer over the bottom and the at least one sidewall of the cavity;
- depositing a layer of silicon nitride over the hemispherical grained polysilicon layer and at least a portion of the surface of the structural layer including an area surrounding the opening of the cavity;
- sputtering a layer of aluminum over a portion of the silicon nitride layer including the area surrounding the opening of the cavity and a portion of the at least one sidewall adjacent the opening;
- and
- oxidizing at least the aluminum layer to form aluminum oxide.
A method of forming a cell container for a memory device comprising:
- providing a structural layer;
- forming a cavity in the structural layer having a bottom and at least one sidewall extending to an opening at a surface of the structural layer;
- depositing a polysilicon layer over the bottom and the at least one sidewall of the cavity;
- depositing a nitride layer over the polysilicon layer and at least a portion of the surface of the structural layer including an area surrounding the opening of the cavity;
- and
- depositing a barrier material over a portion of the nitride layer including the area surrounding the opening of the cavity and a portion of the at least one sidewall adjacent the opening, the barrier material having a higher dielectric constant than that of the nitride layer.
Dependencies are inferred from the claim text.