Polymer Sequence Alters Sensitivity and Resolution in Chemically Amplified Polypeptoid Photoresists

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Semiconductor manufacturing requires sub-10 nm patterning for advanced transistors.
• Traditional chemically amplified resists face challenges in extreme ultraviolet (EUV) lithography due to nanoscale defects.
• Developing novel photoresists with molecular precision is crucial for next-generation lithography.

Purpose of the Study:

• To investigate polypeptoids as a new class of photoresists for high-resolution EUV lithography.
• To explore the impact of molecular control, specifically chain length and monomer sequence, on photoresist performance.
• To identify strategies for optimizing photoresist processing to mitigate variability.

Main Methods:

• Synthesis and characterization of sequence-defined polypeptoids.
• Systematic variation of polypeptoid chain length and monomer sequence.
• Evaluation of photoresist performance, including sensitivity and feature fidelity, under EUV exposure.
• Optimization of postexposure bake conditions.

Main Results:

• A critical chain length threshold was identified for successful pattern formation with polypeptoid resists.
• Monomer sequence significantly influences photoresist sensitivity and feature fidelity, contrary to conventional assumptions.
• Postexposure bake temperature optimization can reduce sequence-dependent variability.

Conclusions:

• Polypeptoids offer precise molecular control for advanced photoresist design in nanoscale lithography.
• Polymer sequence is a powerful, underexplored parameter for tuning resist performance.
• This work presents a promising pathway toward overcoming limitations in EUV lithography.