Method of forming pad patterns using self-align double patterning method, pad pattern layout formed using the same, and method of forming contact holes using self-align double patterning method

Abstract

A self-align patterning method for forming patterns includes forming a first layer on a substrate, forming a plurality of first hard mask patterns on the first layer, forming a sacrificial layer on top surfaces and sidewalls of the first hard mask patterns, thereby forming a gap between respective facing portions of the sacrificial layer on the sidewalls of the first hard mask patterns, forming a second hard mask pattern in the gap, etching the sacrificial layer using the second hard mask pattern as a mask to expose the first hard mask patterns, exposing the first layer using the exposed first hard mask patterns and the second hard mask pattern, and etching the exposed first layer using the first and second hard mask patterns.