Process study and the lithographic performance of commercially available silsesquioxane based electron sensitive resist Medusa 82

Abstract

In the past 2 decades silsesquioxane has gained attention in the Electron Beam Lithography community as a negative tone electron-sensitive resist (HSQ) whose advantages (sub-20 nm resolution, high contrast, low Line Edge Roughness, good shape fidelity and high etch resistance) outnumber its associated drawbacks (limited shelf-life, chemical instability issues, process residuals, low sensitivity, cost). The new silsesquioxane based resist, developed by Allresist GmbH, Medusa 82 (official product name: SX AR-N 8200) and Medusa 82 UV (SX AR-N 8250), its highly sensitive counterpart, have been designed to address all these issues. The objective of this work is to use fundamental Contrast Curve analysis, Dissolution Monitoring and parametric e-beam lithography experiments to study the influence of processing conditions (Post Exposure Bake Temperature, Development duration and developer strength) on the lithographic performance of sub-40 nm thick films.

Keywords

• Electron beam lithography
• Silsesquioxane
• Negative tone electron-sensitive resists
• Resist processing
• Resist contrast
• Nanostructures