METHOD FOR FORMING ELECTRICAL CONNECTIONS BETWEEN CONDUCTING LAYERS IN SEMICONDUCTOR STRUCTURES

摘要

1. Method of making electric connections between conductive layers representing, on different levels of a semiconductor structure, the lines of the circuits, where on a structured conductive layer of a first lower level applied on a layer (12) covering the semiconductor substrate, the electric connections are established using a mask (24, 25) consisting of a least two layers, where the thus obtained structure is blanket coated with an insulating layer (28), where subsequently the upper side of the connections is exposed, and where finally the metal layer (30) partly representing the still to be produced conductive layer of the second level is blanket deposited, characterized in that on the layer (12) covering the semiconductor substrate the conductive layer of the first level which consists of a metal layer (19) and a metallic etch barrier (20) etchable more slowly than the metal layer (19) is blanket deposited, that thereon an interspaced metal layer (21) etchable more quickly than the metal etch barrier (20) is also blanket deposited, that the metal layer (19), the metallic etch barrier (20) and the interspaced metal layer (21) are structured together in accordance with the respective pattern of the conductive layer of the first level, that using the mask (24, 25) consisting of at least two layers and serving as an etch mask the interspaced metal layer (21) is etched to obtain separate regions (21') representing the electrical connections, and that the insulating layer (28) is removed to expose the surface of the separate regions (21') of the interspaced metal layer (21).