| 摘要 |
A method is disclosed for forming a high aspect ratio submicron VLSI interconnect structure. The method makes use of the high diffusivity of aluminum alloyed with germanium and the low eutectic temperature of the alloy for more uniform filling of interconnect structure openings having high aspect ratios. The method comprises preparing a semiconductor device or portion of a semiconductor device that is to receive electrical contact, covering the semiconductor device with an insulating layer, forming an interconnect structure opening through the insulating layer, depositing a layer of germanium in the interconnect structure opening, and reflow sputtering aluminum or aluminum alloy into the interconnect structure opening. Alternatively, the aluminum or aluminum alloy can be cold sputtered into the interconnect structure opening, followed by a low temperature reflow. The aluminum will readily diffuse to the bottom of the interconnect structure opening, assisted by its high diffusivity with the germanium. An interconnect structure is formed thereby with desirable electrical conductivity characteristics even at high aspect ratios. The germanium will also rid the interconnect structure opening of native oxide layers. When forming a contact, a standard diffusion barrier may be deposited before forming the germanium layer.
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