Development of Spin-on Carbon Materials with High Planarization Performance for Multilayer Resist Process

Progress of our new spin-on carbon (SOC) materials development for planarization use in multilayer resist process was described. We designed new SOC materials with different base polymer structure and carbon density, evaluated these planarization performances. It was found that viscoelasticity of base polymer would affect planarization performance in our developed SOC materials. Good planarization performance was obtained on our test pattern, its performance was superior to conventional SOC material novolac and O
2
or CF
4
etching resistance was comparable to the novolac. As functional properties for multilayer lithography process, solubility for common FAB solvent to make coating solution, solvent strip resistance for enabling to stuck layer and thermal stability were also examined to explore the feasibility to multilayer resist process.