Abstract: In the formation of a contact hole within highly limited area, the size of the contact hole does not vary. For achieving such purpose, after a first polysilicon pattern is formed, a concave portion is formed by isotropically etching the predetermined depth of an insulating layer. A second polysilicon spacer is then formed at the sidewall of the first polysilicon pattern and the concave portion. Using the etching process employing the first polysilicon pattern and the second polysilicon spacer as a mask, the contact hole is formed by etching the insulating layer.