Method for production of thin metal-containing layers having low electrical resistance

Abstract

The invention relates to a method for fabricating thin metal-containing layers ( 5 C) having low electrical resistance, firstly a metal-containing starting layer ( 5 A) having a first grain size being formed on a carrier material ( 2 ). Afterwards, a locally delimited thermal region (W) is produced and moved in the metal-containing starting layer ( 5 A) in such a way that a recrystallization of the metal-containing starting layer ( 5 A) is carried out for the purpose of producing the metal-containing layer ( 5 C) having a second grain size, which is enlarged with respect to the first grain size. A metal-containing layer having improved electrical properties is obtained in this way.

1 . Method for fabricating thin metal-containing layers having low electrical resistance, having the following steps: 
 a) formation of a metal-containing starting layer ( 5 A) having a first grain size on a carrier material ( 1 ,  2 ,  3 ,  4 ); and    b) production and movement of a locally delimited thermal region (W) in the metal-containing starting layer ( 5 A) in such a way that a recrystallization of the metal-containing starting layer ( 5 A) is carried out for the purpose of producing a metal-containing layer ( 5 C) having a second grain size, which is enlarged with respect to the first grain size.    
   
   
       2 . Method according to Patent  claim 1 ,  
     characterized in that, in step a), interconnects ( 5 ) are formed in a primary direction (x) and/or in a secondary direction (y), which is essentially perpendicular to the primary direction; and 
 in step b), the movement of the thermal region (W) is carried out essentially in the primary direction (x) and/or in the secondary direction (y) or at an angle of 45 degrees to the primary and secondary direction (x, y).  
 
   
   
       3 . Method according to Patent  claim 1  or  2 ,  
     characterized in that step b) is carried out repeatedly.  
   
   
       4 . Method according to one of Patent  claims 1  to  3 ,  
     characterized in that, in step b), the locally delimited thermal region (W) is produced by means of a fanned-out laser beam, a hot gas, a multiplicity of heating lamps and/or a heating wire.  
   
   
       5 . Method according to one of Patent  claims 1  to  4 ,  
     characterized in that the locally delimited thermal region (W) is formed in strip-type or point-type fashion.  
   
   
       6 . Method according to one of Patent  claims 1  to  5 ,  
     characterized in that, in step a), a metal alloy or a doped metal with an impurity proportion of less than 5% is formed as the metal-containing starting layer ( 5 A).  
   
   
       7 . Method according to one of Patent  claims 1  to  6 ,  
     characterized in that the carrier material has a diffusion barrier layer ( 3 ) and/or a seed layer ( 4 ).  
   
   
       8 . Method according to one of Patent  claims 1  to  7 ,  
     characterized in that, in step a), a damascene method is carried out.  
   
   
       9 . Method according to one of Patent  claims 1  to  8 ,  
     characterized in that the locally delimited thermal region (W) has a temperature of 150 degrees Celsius to 450 degrees Celsius.  
   
   
       10 . Method according to one of Patent  claims 1  to  9 ,  
     characterized in that the recrystallization is carried out in a protective gas atmosphere.