Multilayer copper structure for improving adhesion property
AssigneeTegal Corporation
InventorTue Nguyen
Life of this patent
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Abstract
A multilayer copper structure has been provided for improving the adhesion of copper to a diffusion barrier material, such as TiN, in an integrated circuit substrate. The multilayer copper structure comprises a thin high-resistive copper layer to provide improved adhesion to the underlying diffusion barrier layer, and a low-resistive copper layer to carry the electrical current with minimum electrical resistance. The invention also provides a method to form the multilayer copper structure.
Claims25
A method to form a multilayer metal structure for improving adhesion to an underlying diffusion barrier layer, the method comprising the steps of:
- a) forming a thin high-resistive metal layer, whereby this high-resistive layer serves to improve the adhesion of metal to the underlying diffusion barrier layer;
- b) treating the thin high-resistive metal layer to reduce the resistance of the thin high-resistive metal layer, whereby the treatment step improves the conductivity of the high-resistive metal layer without destroying the adhesion property;
- and
- c) forming a low-resistive metal layer, in which the resistivity of the low-resistive layer is lower than the resistivity of the treated high-resistive layer, whereby this layer serves to carry the electrical current with minimum electrical resistance.
A method to form a multilayer metal structure for improving adhesion to an underlying diffusion barrier layer, the method comprising the steps of:
- a) forming a thin high-resistive metal layer, whereby this high-resistive layer serves to improve the adhesion of metal to the underlying diffusion barrier layer;
- b) treating the thin high-resistive metal layer to reduce the resistance of the thin high-resistive metal layer by introducing organic compounds to reduce metal oxide to metal and volatile organic by-products, whereby the treatment step improves the conductivity of the high-resistive metal layer without destroying the adhesion property;
- and
- c) forming a low-resistive metal layer, in which the resistivity of the low-resistive layer is lower than the resistivity of the treated high-resistive layer, whereby this layer serves to carry the electrical current with minimum electrical resistance.
A method to form a multilayer metal structure for improving adhesion to an underlying diffusion barrier layer, the method comprising the steps of:
- a) forming a thin high-resistive metal layer, whereby this high-resistive layer serves to improve the adhesion of metal to the underlying diffusion barrier layer;
- b) treating the thin high-resistive metal layer to reduce the resistance of the thin high-resistive metal layer by introducing a gettering metal precursor, the gettering metal being a metal wherein its oxide conducts electricity, whereby the treatment step improves the conductivity of the high-resistive metal layer without destroying the adhesion property;
- and
- c) forming a low-resistive metal layer, in which the resistivity of the low-resistive layer is lower than the resistivity of the treated high-resistive layer, whereby this layer serves to carry the electrical current with minimum electrical resistance.
A method to form a multilayer metal structure for improving adhesion to an underlying diffusion barrier layer, the method comprising the steps of:
- a) forming a thin high-resistive metal layer, whereby this high-resistive layer serves to improve the adhesion of metal to the underlying diffusion barrier layer;
- b) treating the thin high-resistive metal layer to reduce the resistance of the thin high-resistive metal layer by introducing an alloying metal precursor, the alloying metal is selected from a group of metals that forms an alloy with metal oxide such that the alloy is not non-conducting of electricity, whereby the treatment step improves the conductivity of the high-resistive metal layer without destroying the adhesion property;
- and
- c) forming a low-resistive metal layer, in which the resistivity of the low-resistive layer is lower than the resistivity of the treated high-resistive layer, whereby this layer serves to carry the electrical current with minimum electrical resistance.
Dependencies are inferred from the claim text.