| 摘要 |
A self-aligned contact structure is formed by forming a spacer that covers a sidewall of a self-aligned contact hole; forming an upper conductive layer that fills the self-aligned contact hole on the entire surface of a semiconductor substrate having the spacer; and planarizing the upper conductive layer and sacrificial mask patterns until upper surfaces of recessed mask patterns are exposed to form a plug surrounded by the spacer. Formation of a self-aligned contact structure includes forming parallel interconnection patterns (350) on a semiconductor substrate (100), where each interconnection pattern has an interconnection and a mask pattern stacked in sequence; forming interlayer insulating layer patterns that fill gap regions between the interconnection patterns; partially etching the mask patterns to form recessed mask patterns that define grooves between the interlayer insulating layer patterns; forming sacrificial mask patterns (600) that fill the grooves; etching a predetermined region of one of the interlayer insulating layer patterns using the sacrificial mask patterns as etching masks to form a self-aligned contact hole (750) that exposes a predetermined region of the substrate; forming a spacer (650) that covers a sidewall of the self-aligned contact hole; forming an upper conductive layer that fills the self-aligned contact hole on the entire surface of the substrate having the spacer; and planarizing the upper conductive layer and the sacrificial mask patterns until upper surfaces of the recessed mask patterns are exposed to form a plug surrounded by the spacer. |
