| 摘要 |
A method for using a self-aligned electromigration barrier metal and flow oxidation mask utilizing titanium nitride as the preferred embodiment. After providing a metallic mask layer, contact openings in a semiconductor substrate are sputtered with suitable metal (in the preferred embodiment, titanium) in a suitable atmosphere (in the present embodiment, nitrogen) to deposit a thin layer of material at the exposed junction sites. This deposited material serves as a barrier to spiking with an overlying metallic interconnect layer, improves contact adherence, and serves as an oxidation mask during subsequent high temperature flow processing steps. The metallic mask layer is removed, and optionally an interlevel oxide layer is flowed to provide a better contact between a subsequent metallic interconnect level and the barrier metal/oxidation mask material. After any flow step, a metallic contact layer may be formed to the silicon junction through the barrier metal/oxidation mask material. Thereafter, standard processing of the substrate may continue. The barrier metal/oxidation mask eliminates spiking of semiconductor juctions by metallic interconnect layers, provides a good contact interface, and protects semiconductor junctions from formation of an oxide layer during a flow process.
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