Integrated process for fuse opening and passivation process for Cu/Low-K IMD

Abstract

A new process flow is provided for the creation of a fuse contact and a bond pad. The invention starts with a semiconductor substrate over the surface of which is provided top level metal and fuse metal in the surface of a layer of insulation deposited over the surface of the substrate. A first etch stop layer is deposited over the surface of the layer of insulation over which a first passivation layer is deposited, an opening is created through these layers exposing the top level metal. A metal plug is created overlying the exposed surface of the top level metal. A stack of a patterned and etched hard mask layers, having been deposited at part of the creation of the metal plug and overlying a layer of metal plug material, remains in place over the surface of the created metal plug. A second layer of passivation material is deposited, the second layer of passivation is patterned and etched exposing the surface of the first layer of passivation overlying the fuse metal and exposing the surface of the stack of hard mask layers overlying the created metal plug. The stack of hard mask layers is then removed from the surface of the metal plug, exposing the surface of the metal plug to serve as a contact pad and further reducing the thickness of the first layer of passivation over the surface of the fuse metal, making the fuse more accessible for fuse blowing.

1 - 38 . (canceled)  
   
   
       39 . A fuse and contact pad opening over a substrate, comprising: 
 a substrate, said substrate having been provided with a pattern of top level metal and fuse metal;    a first layer of etch stop material having been deposited over the substrate;    a first layer of passivation material having been deposited over the first layer of etch stop material;    said first layer of passivation material and said first layer of etch stop material having been patterned, an opening having been created through said first layer of passivation material and said first layer of etch stop material, said opening exposing with said pattern of top level metal;    a patterned layer of contact pad material aligned with and in contact with said pattern of top level metal, a thickness of said first layer of passivation material having been first reduced where the first layer of passivation material is not covered by the patterned layer of contact pad material;    a second layer of passivation material deposited over the first layer of passivation material, thereby including said patterned layer of contact pad material, said second layer of passivation material comprising one layer of passivation material;    a first opening having been created through the second layer of passivation, said first opening being aligned with said patterned layer of contact pad material, said first opening having a cross section of which a diameter decreases when proceeding from the surface of the patterned layer of contact pad material to the surface of the second layer of passivation material, further a second opening having been created through the second layer of passivation, said second opening being aligned with said fuse metal, said second opening exposing said first layer of passivation material; and    a thickness of said first layer of passivation material having been second reduced where said first layer of passivation material overlies said fuse metal.    
   
   
       40 . The fuse and contact pad opening of  claim 39 , additionally alloying said exposed surface of said pattern of top level metal.  
   
   
       41 . The fuse and contact pad opening of  claim 39 , said substrate having been provided with active and passive semiconductor components, said active and passive semiconductor components being interconnected with at least one layer of interconnect traces created over said substrate, said pattern of top level metal and fuse metal being electrically connected to said interconnect traces being provided in said at least one layer of interconnect traces created over said substrate.  
   
   
       42 . The fuse and contact pad opening of  claim 39 , said contact pad material comprising aluminum or an alloy thereof.  
   
   
       43 . The fuse and contact pad opening of  claim 42 , said aluminum or an alloy thereof being deposited to a thickness of about 12,000 Angstrom.  
   
   
       44 . The fuse and contact pad opening of  claim 39 , said first layer of passivation material comprising silicon dioxide.  
   
   
       45 . The fuse and contact pad opening of  claim 44 , said silicon dioxide being deposited to a thickness of about 8,000 Angstrom.  
   
   
       46 . The fuse and contact pad opening of  claim 39 , said first layer of etch stop material being deposited to a thickness of about 750 Angstrom.  
   
   
       47 . The fuse and contact pad opening of  claim 39 , said second layer of passivation comprising silicon nitride.  
   
   
       48 . The fuse and contact pad opening of  claim 47 , said silicon nitride being deposited to a thickness of about 8,000 Angstrom.