Patent ID: 6730570
Filing Date: 2004-05-04
Classification: H01L

Abstract:
A method for forming a self-aligned contact of a semiconductor device comprising:forming conductive structures on a semiconductor substrate; forming spacers on sidewalls of the conductive structures; covering the conductive structures with an interlayer dielectric film; selectively etching a portion of the interlayer dielectric film to expose a portion of the semiconductor substrate between the conductive structures to form a self-aligned contact hole having a sidewall exposing the spacers of the conductive structures; adding a buffer layer for reducing a consumption of the interlayer dielectric film exposed through the sidewall of the self-aligned contact hole by depositing an insulation material on the sidewall of the self-aligned contact hole, on a bottom face of the self-aligned contact hole, and on the interlayer dielectric film, wherein a thickness of the buffer layer at an upper portion of the self-aligned contact hole is greater than that the thickness of the buffer layer at the bottom face of the self-aligned contact hole; partially removing the buffer layer on the bottom face of the self-aligned contact hole such that the buffer layer remains on the sidewall of the self-aligned contact hole; and depositing a conductive material in the self-aligned contact hole to form a self-aligned contact making contact with the semiconductor substrate.