| 摘要 |
PURPOSE:To realize the self-alignment formation of a very fine contact hole, by forming a third insulating film by forming a first thin hole in a second insulating film formed on a substrate, forming a second thin hole by using a mask in which the third film is left on the side wall of the thin hole, forming a fourth insulating film on the surface of the second thin hole, and eliminating the third insulating film. CONSTITUTION:After a silicon oxide film 29 and a first silicon nitride film 30 are deposited on the surface of a semiconductor substrate 1, resist 27 is spread thereon and patterned. By selectively eliminating the above films 29 and 30, a first thin hole 28 is formed. Next, the resist 27 is exfoliated, and a second silicon nitride film 31 is deposited, which is subjected to anisotropic etching and left on the side wall of the thin hole 28. By using the nitride films 30, 31 as masks, the substrate 1 is subjected to anisotropic etching, and a second thin hole 32 is bored, on the surface of which a silicon oxide film 33 is formed. By exfoliating the nitride films 30, 31, a contact hole 35 is formed. The width lcan be adjusted by the width l' of the nitride film 31 left on the side wall, i.e., the thicknesses of the first and the second nitride films, so that the width of 0.2-0.3mum can be easily obtained. |
