Conductive Polymer Composition for Electron Beam Resist Patterning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current antistatic films for electron beam lithography face challenges such as charge accumulation, acid diffusion, and pattern defects due to the use of polyaniline-based conductive polymers, which affect the accuracy and resolution of semiconductor device manufacturing.
Innovation Solution
A conductive polymer composition comprising a polyaniline-based conductive polymer with a repeating unit and a hydrogencarbonate cation, along with a nonionic surfactant and water-soluble polymer, is used to form an antistatic film that reduces acid diffusion and enhances film-formability and peelability, thereby improving positional accuracy and pattern quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a polyaniline-based conductive polymer is used to form an antistatic film, then charge dissipation efficiency is improved, but acid diffusion to the resist layer increases causing pattern defects
Solution Approach 1:
A buffer layer comprising a basic compound is introduced between the polyaniline-based conductive polymer and the electron beam resist. This buffer layer acts as an intermediary that neutralizes acid diffusing from the conductive polymer, preventing pattern defects while maintaining charge dissipation functionality. The buffer layer specifically uses compounds like amines or ammonium salts that can accept protons without significantly increasing film resistivity.
2Ease of operation
If the conductive polymer film thickness is reduced to improve peelability, then film removal ease is improved, but charge dissipation efficiency deteriorates
Solution Approach 1:
The invention optimizes the film thickness parameters of both the conductive polymer layer and the buffer layer to achieve balanced performance. The conductive polymer film is maintained at a thickness that ensures sufficient charge dissipation (typically not too thin), while the buffer layer thickness is optimized to provide adequate acid neutralization. This parameter optimization allows the conductive polymer film to be sufficiently thin for easy peelability while maintaining charge dissipation efficiency through the combined layer structure.
3Ease of manufacture
If a complex containing polyaniline and polyacid is used, then film-formability is improved, but chemical effects on the resist underneath increase
Solution Approach 1:
The buffer layer of basic compound serves as a protective intermediary between the polyaniline-polyacid complex and the electron beam resist. It neutralizes excess acid and chemical species that could otherwise diffuse into and affect the resist layer, thereby reducing chemical effects on the resist while allowing the complex to maintain its film-formability advantages.
4Object-generated harmful factors
If strong base is added to neutralize acid, then acid diffusion is reduced, but handling safety and neutralization control deteriorate
Solution Approach 1:
The invention changes the chemical parameter of the neutralizing agent from strong base to buffer compounds (amines, ammonium salts). These buffer compounds provide gentler neutralization with better handling safety and more controllable neutralization程度, preventing both excessive neutralization that could increase film resistivity and insufficient neutralization that would leave acid diffusion unchecked.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition achieves high-efficiency charge dissipation, low resistivity, and excellent antistatic properties, reducing pattern defects and maintaining high-resolution resist patterns during electron beam writing and development.
Implementation Method 1
a polyaniline-based conductive polymer having at least one kind of a repeating unit represented by general formula (1)... high-efficiency diffusion property for a charge charged during writing
Implementation Method 2
a hydrogencarbonate including a cation represented by general formula (2-1) or (2-2)... capable of alleviating the acidity of the polyaniline-based conductive polymer
Data Source
AI summary
The present invention is a conductive polymer composition containing: (A) a polyaniline-based conductive polymer having at least one repeating unit of the formula (1); and (B) a hydrogencarbonate including a cation of the formula (2-1) or (2-2). Here, R1 to R4 each represent a hydrogen atom, an acidic group, a hydroxy group, a nitro group, a halogen atom, a linear or branched alkyl group, a hydrocarbon group containing a hetero atom, or a hydrocarbon group partially substituted with a halogen atom. X represents a monovalent alkali metal selected from lithium, sodium, potassium, and cesium, R101 to R104 each represent a hydrogen atom, an alkyl group, an alkenyl group, an oxoalkyl group, an oxoalkenyl group, an aryl group, an aralkyl group, or an aryloxoalkyl group. R101 and R102, R103 and R104, and R101, R102, and R104 optionally form a ring. This provides a conductive polymer composition that can form an antistatic film for electron beam resist writing.