Maskless Submicrometer Pattern Formation of Cr Films by Focused Sb Ion Implantation

Maskless submicrometer patterning of Cr films was done by implanting focused Sb + ion and by plasma etching using CCl 4 gas. Dose and depth dependence of the etching rate and Sb profiles were measured to investigate the concentration dependence of Sb. The present patterning characteristics are compared with conventional patterning characteristics using Au masks. It was found that a sharp threshold dose exists to form an etch resistant layer and this enables formation of few hundred nanometer thick, submicrometer patterns with vertical side walls. It was also found that the resistivity of patterned Cr films increase only 10%.