| 摘要 |
PURPOSE:To facilitate the process of flattening an interlayer insulating film and to prevent wire from an increased resistance or disconnection attributable to poor coverage of a metal wiring layer by a method wherein a lower metal wiring layer is thinner than an upper metal wiring layer. CONSTITUTION:In a two-layer wiring structure, an upper Al wiring layer 101 formed by spattering is, for example, 8000-12000Angstrom thick while a lower Al wiring layer 103 is 4000-6000Angstrom thick. Accordingly, an interlayer insulating film 108 is remarkably flattened and the Al covering feature may be improved at a contact hole region 107 where wires cross each other. A similar effect may be achieved in a multilayer interconnection of three or more layers when a lower layer wiring may be made thinner than an upper layer. For wiring, instead of Al, such an alloy as Al.Si, Al.Cu.Si, or Al.Ti.Si, or a laminate structure of Ti, W, and Al, may be used. In a structure of this design, an interlayer film may be kept from growing too thick, and an interlayer junction hole may be built very fine.
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