Method of depositing copper using physical vapor deposition

Abstract

The present method of forming an electronic structure includes providing a tantalum base layer and depositing a layer of copper on the tantalum layer, the deposition being undertaken by physical vapor deposition with the temperature of the base layer at 50.degree. C. or less, with the deposition taking place at a power level of 300 W or less.

What is claimed is: 
     
         1 . A method of forming an electronic structure comprising:
 providing a tantalum layer; and   depositing a layer of copper of a substantially uniform thickness of 30 angstroms or less on the tantalum layer.   
     
     
         2 . The method of  claim 1 , wherein the layer of copper is deposited by physical vapor deposition with the temperature of the tantalum layer at 50° C. or less. 
     
     
         3 . The method of  claim 2 , wherein the layer of copper is deposited by physical vapor deposition with the temperature of the tantalum layer at approximately 30° C. 
     
     
         4 . The method of  claim 1 , wherein the base layer is formed on a layer of oxide that is formed on the surface of a wafer. 
     
     
         5 . The method of  claim 4 , wherein the wafer, the layer of oxide, and the base layer are transformed to a chamber, after forming the base layer, to avoid contamination and to provide a vacuum. 
     
     
         6 . The method of  claim 5 , further comprising a pump-down step to provide the vacuum. 
     
     
         7 . The method of  claim 1 , wherein the layer of copper is deposited by physical vapor deposition at a power level of 300 W or less. 
     
     
         8 . The method of  claim 7 , wherein the layer of copper is deposited by physical vapor deposition at a power level of approximately 200 W. 
     
     
         9 . The method of  claim 1 , further comprising rapid cooling of the layer of oxide and the base layer, wherein rapid cooling is performed for an extended period of time. 
     
     
         10 . The method of  claim 1 , wherein a power level of 300 W or less and a cool base layer promote a smooth, continuous, uniform, and thin formation of the layer of copper. 
     
     
         11 . The method of  claim 1 , wherein said electronic structure is incorporated in a system. 
     
     
         12 . The method of  claim 1 , wherein the system is selected from the group consisting of a vehicle, and a computer. 
     
     
         13 . A method of forming an electronic structure incorporated in a hand-held device, said method comprising:
 providing a base layer on a layer of oxide that is formed on the surface of a wafer; and   depositing a layer of copper of a substantially uniform thickness of 30 angstroms or less on the tantalum layer.   
     
     
         14 . The method of  claim 13 , wherein the layer of copper is deposited by physical vapor deposition with the temperature of the tantalum layer at 50° C. or less. 
     
     
         15 . The method of  claim 13 , wherein the layer of copper is deposited by physical vapor deposition at a power level of 300 W or less. 
     
     
         16 . The method of  claim 13 , wherein the wafer with the layer of oxide and the base layer are transformed to a chamber, after forming the base layer, to avoid contamination and to provide a vacuum. 
     
     
         17 . The method of  claim 16 , further comprising a pump-down step to provide the vacuum. 
     
     
         18 . The method of  claim 13 , further comprising rapid cooling of the layer of oxide and the base layer. 
     
     
         19 . The method of  claim 13 , wherein the power level of 300 W or less and a cool base layer promote a smooth, continuous, uniform, and thin formation of the layer of copper. 
     
     
         20 . The method of  claim 19 , wherein the rapid cooling is performed after forming of the tantalum layer.