Seed layer of copper interconnection via displacement
AssigneeChang Chun Petrochemical Co., Ltd.
InventorsYang Wu, Chi-Chao Wan
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Abstract
A process for the fabrication of submicron copper interconnection useful on IC structures without deposition of copper seed is described. A dense metal layer can be deposited through contact displacement reaction between diffusion barrier layer and metal ions in solution under appropriate conditions. The metal layer formed by the displacement deposition can serve as the conducting material for subsequent copper electroplating. Moreover, the costly process for applying seed layer through CVD or PVD can be eliminated.
Claims10
A process for displacement depositing a seed layer over a barrier layer on a substrate, wherein said seed layer thus deposited can act as an electrically conducting layer required during filling fine vias through electroplating;
- said process comprising steps of:
- (1) preparing displacement deposition solution, consisting of 0.2-20 g/l of palladium ionic compound, 0.6-60 g/l of halogen ionic compound, 0.09-9 g/l of inorganic acid and 10-1000 ppm of surfactant, wherein said surfactant is polyethylene glycol, polypropylene glycol, or ethylene oxide (EO)/propylene oxide (PO) copolymer and having a pH of about 1 to 7.0;
- and
- (2) immersing said substrate having said barrier layer thereon in said depositing solution prepared as in step (1) at a temperature of 20 to 70° C. for 1-20 minutes.
A process for displacement depositing a seed layer over a titanium nitride barrier layer on a substrate, wherein said seed layer thus deposited can act as an electrically conducting layer required during filling fine vias through electroplating;
- said process comprising steps of:
- (1) preparing displacement deposition solution, consisting of 0.2-20 g/l of silver ionic compound, 0.6-60 g/l of halogen ionic compound, 0.09-9 g/l of inorganic acid and 10-1000 ppm of surfactant, wherein said surfactant is polyethylene glycol, polypropylene glycol, or ethylene oxide (EO)/propylene oxide (PO) copolymer and having a pH of about 1 to 7.0;
- and
- (2) immersing said substrate having said barrier layer thereon in said depositing solution prepared as in step (1) at a temperature of 20 to 70° C. for 1-20 minutes.
Dependencies are inferred from the claim text.