Patent ID: 7205232

Claim:
A method of forming a self-aligned contact structure, comprising: forming a plurality of parallel interconnection patterns on a semiconductor substrate, wherein each of the interconnection patterns 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 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 that exposes a predetermined region of the semiconductor substrate; forming a spacer 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 semiconductor 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.