Method for applying a textured insulation layer to a metal layer

Abstract

The present invention relates to a method for applying a structured insulating layer ( 14 ) onto a metal layer ( 12 ), in which insulation material ( 14 ) is applied onto the metal layer ( 12 ), overlayer material ( 16 ) is applied to the insulating layer ( 14 ) and insulating material ( 14 ) and overlayer material ( 16 ) are etched in a plasma etching process, the overlayer material ( 16 ) being structured following the application of insulating layer ( 14 ), and, following the structuring of overlayer material ( 16 ), a plasma etching process is carried out, a structured and planarized insulating layer ( 14 ) being created.

what is claimed is:  
     
         1 . A method for applying a structured insulating layer ( 14 ) onto a metal layer ( 12 ), in which 
 insulating material ( 14 ) is applied onto the metal layer ( 12 ),    overlayer material ( 16 ) is applied onto the insulating layer ( 14 ) and    insulating material ( 14 ) and the overlayer material ( 16 ) are etched in a plasma etching process, wherein,    the overlayer material ( 16 ) is structured subsequently to the application onto the insulating layer ( 14 ), and    subsequently to the structuring of the overlayer material ( 16 ), a plasma etching process is carried out, a structured and planarized insulating layer ( 14 ) being created.    
     
     
         2 . The method as recited in  claim 1 , wherein, with respect to the overlayer material ( 16 ), lacquer is involved.  
     
     
         3 . The method as recited in  claim 1  or  2 , wherein the overlayer material ( 16 ) is structured by photolithography.  
     
     
         4 . The method as recited in one of the preceding claims, wherein in the case of the insulating layer ( 14 ), an oxide layer (TEOS) is involved.  
     
     
         5 . The method as recited in one of the preceding claims, wherein the plasma etching process is carried out in one step, the ratio of the overlayer material etching rate to the insulating material etching rate being 1 ±0.4.  
     
     
         6 . The method as recited in one of the preceding claims, wherein the plasma etching process has a plurality of steps, 
 in a first step at least one isotropic depression ( 24 ) being etched into the insulating layer ( 14 ),    in a second step at least one anisotropic depression ( 26 ) being etched into the insulating layer ( 14 ),    in a third step a planarization taking place and    in a fourth step the anisotropic depression ( 26 ) being etched to a completed through hole ( 28 ).    
     
     
         7 . The method as recited in one of the preceding claims, wherein the plasma etching process has a plurality of steps, 
 in a first step the ratio of the overlayer material etching rate to the insulating material etching rate being greater than 1, primarily the overlayer material ( 16 ) being etched, and at least one step ( 30 ) being defined in the insulating layer ( 14 ),    in a second step the ratio of the overlayer material etching rate to the insulating material etching rate being 1 ±0.4, at least one depression ( 30 ) being etched into the insulating layer ( 14 ) and planarization being carried out,    in a third step the depression ( 30 ) being etched further over a fixed period, and    in a fourth step the depression ( 30 ) being etched to a completed through hole ( 28 ).    
     
     
         8 . The method as recited in one of the preceding claims, wherein the plasma etching process has a plurality of steps, 
 in a first step the ratio of the overlayer material etching rate to the insulating material etching rate being less than 1, at least one step being defined in the insulating layer over a fixed period,    in a second step the ratio of the overlayer material etching rate to the insulating material etching rate being greater than 1, primarily overlayer material being etched,    in a third step the ratio of the overlayer material etching rate to the insulating material etching rate being 1 ±0.4, at least one depression being etched into the insulating layer and planarization being carried out,    in a fourth step the depression being etched further over a fixed period, and    in a fifth step the depression being etched to a completed through hole.    
     
     
         9 . The method as recited in one of the preceding claims, wherein the insulating material ( 14 ) is applied by a one-time depositing.  
     
     
         10 . The method as recited in one of the preceding claims, wherein subsequently to the plasma etching process, remaining overlayer material ( 16 ) is removed by plasma stripping.  
     
     
         11 . The method as recited in one of the preceding claims, wherein an additional metal layer is applied onto the finished set-up made up of the metal layer ( 12 ) and the insulating layer ( 14 ).