| 摘要 |
PURPOSE: A metallization method for a memory device is provided to prevent oxidation of metallization layers such as word lines and/or bit lines. CONSTITUTION: On a silicon substrate(1), a gate oxide layer(2), a polysilicon layer(3), a diffusion barrier(4), and a metallization layer(5) are successively formed as a stack. Tungsten nitride or titanium nitride may be used for the diffusion barrier(4), and tungsten is preferably used for the metallization layer(5). A mask pattern(6) is then formed on the metallization layer(5), and so the metallization layer(5) and the diffusion barrier(4) exposed thereunder are etched. Subsequently, an anti-oxidation layer(7) is formed on the entire exposed surface and then anisotropically etched. The anti-oxidation layer(7) may use an oxide layer, a nitride layer, or a metallic insulating layer. Thereafter, the polysilicon layer(3) exposed out of the anti-oxidation layer(7) is etched. In the following oxidation process, the metallization layer(5) is protected from permeation of oxygen by the anti-oxidation layer(7).
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