Method of sputtering copper to fill trenches and vias
First Claim
1. A method of providing a complete copper fill of a trench or via or other feature upon a surface of a semiconductor workpiece, said method comprising the steps of:
- sputter depositing at least one wetting layer of copper to wet and bond to said surface while said surface is at a temperature ranging from about 20°
C. to about 250°
C., followed by sputter depositing at least one fill layer of copper over said surface while said surface is at a temperature ranging between about 200°
C. and about 600°
C.
1 Assignment
0 Petitions
Accused Products
Abstract
The present disclosure pertains to a method of filling features (typically trenches or vias) on a semiconductor workpiece surface with copper using sputtering techniques previously believed incapable of achieving a copper fill. In particular, when the feature is to be filled with a single, continuous application of sputtered copper, the surface of the substrate to which the sputtered copper is applied should range between about 200° C. and about 600° C.; preferably the surface temperature of the substrate ranges between about 300° C. and about 500° C. When the feature is to be filled using a thin wetting layer of copper, followed by a fill layer of copper, the wetting layer may be applied by sputtering techniques or by other methods such as evaporation or CVD, while the fill layer of copper is applied using sputtering techniques. The thin wetting layer of copper is applied at a substrate surface temperature ranging between about 20° C. to about 250° C., and subsequently the temperature of the substrate is increased, with the application of the sputtered copper fill layer beginning at above at least about 200° C. and continuing while the substrate temperature is increased to a temperature as high as about 600° C. Preferably the substrate temperature during application of the sputtered fill layer ranges between about 300° C. and about 500° C.
-
Citations
14 Claims
-
1. A method of providing a complete copper fill of a trench or via or other feature upon a surface of a semiconductor workpiece, said method comprising the steps of:
sputter depositing at least one wetting layer of copper to wet and bond to said surface while said surface is at a temperature ranging from about 20°
C. to about 250°
C., followed by sputter depositing at least one fill layer of copper over said surface while said surface is at a temperature ranging between about 200°
C. and about 600°
C.- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
Specification