摘要 |
A method of fabricating gate trench utilizing pad pullback technology is disclosed. A semiconductor substrate having thereon a pad oxide layer and pad layer is provided. Trench capacitors are formed in a memory array region of the semiconductor substrate. Each of the trench capacitors has a trench top oxide (TTO) that extrudes from a main surface of the semiconductor substrate. The pad layer is recessed from its top and covered with a polysilicon layer. Isolation trenches are formed in the substrate and then filled with photoresist. The TTO is then stripped. The pad layer that is not covered by the photoresist is pulled back to define the gate trench.
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