A novel 248-nm wet-developable BARC for trench applications

Abstract

A novel polyamic acid-based, 248-nm wet-developable BARC has been prepared to improve structure clear-out and lessen post-development residue. This material showed an excellent process window and controllable development rates that can be achieved by simply changing the formulation. It is a highly absorbing BARC with n and k values equal to 1.73 and 0.49, respectively. Lithography with this material has shown 180-nm dense profiles with P338 and M230Y. These profiles exhibited minimal undercutting with good clearing between the lines. Clear-out has been demonstrated for 120-nm trenches. Post-development residue of the material was tested at various temperatures and was determined to be 6 Å or less. In addition, sublimation was evaluated.