Patterning method and method of forming memory device

摘要

A method of forming memory device is provided. A substrate having at least two cell areas and at least one peripheral area between the cell areas is provided. A target layer, a sacrificed layer and a first mask layer having first mask patterns in the cell areas and second mask patterns in the peripheral area are sequentially formed on the substrate. Sacrificed layer is partially removed to form sacrificed patterns by using the first mask layer as a mask. Spacers are formed on sidewalls of the sacrificed patterns. The sacrificed patterns and at least the spacers in the peripheral area are removed. A second mask layer is formed in the cell areas. Target layer is partially removed, using the second mask layer and remaining spacers as a mask, to form word lines in the cell areas and select gates in a portion of cell areas adjacent to the peripheral area.

主权项

1. A patterning method, comprising:
providing a substrate having a first area and a second area; sequentially forming a target layer, a sacrificial layer and a first mask layer on the substrate, wherein the first mask layer has a plurality of first mask patterns located in the first area and a plurality of second mask patterns located in the second area; removing a portion of the sacrificial layer by using the first mask layer as a mask, so as to form a plurality of sacrificial patterns; removing the first mask layer; forming a spacer on a sidewall of each of the sacrificial patterns; removing the sacrificial patterns; at least removing the spacers in the second area; forming a second mask layer on the substrate to cover a portion of the first area adjacent to the second area; removing a portion of the target layer by using the second mask layer and the remaining spacers as a mask, so as to form a plurality of first target patterns in the first area and form a second target pattern in the portion of the first area adjacent to the second area; and removing the second mask layer and the remaining spacers.