| 摘要 |
PURPOSE:To make the margin for mask alignment unnecessary, by forming a step-difference having a sidewall which is parallel with an isolation boundary and has a specified inclination angle against a substrate surface, and protruding toward a dielectric isolation region side, depositing an interlayer insulating film on the step-difference, and then anisotropically etching a contact hole. CONSTITUTION:In the vicinity of an isolation boundary neighboring with a portion where a contact hole 6 to a diffusion layer 4 is to be formed, a pattern of gate material, e.g., polysilicon 8 is formed. A sidewall spacer is formed by anisotropic etching after a CVD SiO2 film, e.g., is deposited. By this working process, a sidewall spacer 9 is formed, also on the side surface of the polysilicon pattern 8 in the vicinity of the isolation boundary. As the spacer is formed by anisotropic etching, its side surface 9a has an inclination angle theta larger than or equal to 60 deg.. The contact hole 6 is formed by anisotropic etching such as reactive ion etching applying, e.g., CHF3 gas. In this process, a second sidewall 10 of the interlayer insulating film material is formed also on the side surface of the sidewall spacer 9.
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