Conducting polyaniline coatings for submicron lithography and SEM metrology

Polyaniline is a family of soluble, electrically conducting polymers that has a potential for a number of applications, in particular in the area of lithography. This paper focuses on a new family of water soluble conducting polyanilines made by oxidatively polymerizing aniline monomers on a polymeric acid template. The resulting polyanilines readily dissolve in water. These polymers are found to function as effective spin- applied, removable discharge layers for electron-beam lithography. In addition, they also provide a non-destructive method of performing high resolution scanning electron microscopic (SEM) metrology of masks or device wafers. It will also be shown that polyaniline can be patterned with submicron resolution. First, polyaniline itself can be inherently imaged resulting in a water developable, negative conducting resist capable of 0.25 micrometer resolution. In addition, a number of indirect methods of patterning polyaniline using conventional photoresist technology are described.