| 摘要 |
Nonvolatile memory wordlines (160) are formed as sidewall spacers on sidewalls of row structures (280). Each row structure may contain floating and control gates (120, 140), or some other elements. Pedestals (340) are formed adjacent to the row structures before the conductive layer (160) for the wordlines is deposited. The pedestals are formed in the area of the contact openings (330.1) that will be etched in an overlying dielectric (310) to form contacts to the wordlines. The pedestals raise the top surface of the wordline layer near the contact openings, so the contact opening etch can be made shorter. The pedestals also increase the minimum thickness of the wordline layer near the contact openings, so the loss of the wordline layer during the etch of the contact openings becomes less critical, and the photolithographic tolerances required for patterning the contact openings can be relaxed. The pedestals can be dummy structures (they may have no electrical functionality).
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