| 摘要 |
PURPOSE:To increase the contact areas of upper and lower layer wirings without augmenting a projected area, and to lower electric resistance without deteriorating the degree of integration by forming the contact surfaces of the upper and lower layer wirings of a multilayer interconnection into curved surfaces. CONSTITUTION:A contact hole is shaped to an silicon dioxide film 2 on a substrate 1, and a lower-layer metallic wiring 3 and an inter-layer insulating film 4 are formed onto the contact hole. A through-hole 5 is shaped to the film 4 by using an isotropic etching method or the combination of, the isotropic etching method and an anisotropic etching method, and a recessed section 7 is formed to the wiring 3 by employing the isotropic etching method through the hole 5. The film 4 is etched until the inner surface of the hole 5 coincides with the edge of the recessed section 7, and an upper-layer metallic wiring 6 is shaped, thus forming a multilayer interconnection. Accordingly, the contact surfaces of the upper and lower layer wirings are shaped in curved surfaces, thus increasing contact areas, then lowering electric resistance without deteriorating the degree of integration.
|
