Chemi-epitaxy Directed Self-Assembly Sub-25 nm Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current photolithography techniques are limited in achieving feature sizes smaller than 25 nm, necessitating the development of new methods for improved resolution in semiconductor integrated circuit production.
Innovation Solution
A method involving the use of photo-sensitive components such as photo-decomposable cross-linking agents, photo-base generators, or photo-decomposable bases in a radiation sensitive material, which are imaged, cross-linked, and then developed to form a block copolymer pattern, enabling self-assembly and directed patterning on a substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If photolithography is used to manufacture semiconductor integrated circuits, then patterns can be transferred to the substrate, but the minimum feature size is limited to about 25 nm
Solution Approach 1:
The process is divided into two stages: first forming a self-assembled block copolymer pattern with nanoscale features, then using this pattern as a template to guide the formation of the final circuit pattern. This segmentation allows the system to achieve features smaller than 25 nm by combining self-assembly with controlled patterning
Solution Approach 2:
A self-assembled block copolymer pattern is formed in advance on the substrate before the final pattern transfer. This preliminary pattern serves as a guide for subsequent lithography steps, enabling the formation of sub-25 nm features that would be impossible to achieve with photolithography alone
2Manufacturing precision
If self-assembly of block copolymers is used to improve resolution, then feature sizes can be reduced below 25 nm, but the method requires new approaches beyond conventional photolithography
Solution Approach 1:
The block copolymer system performs self-assembly automatically when conditions are right, forming ordered nanoscale patterns without requiring complex external guidance. The system uses its own internal thermodynamic driving forces to create the desired pattern, reducing the need for complex process equipment
3Measurement precision
If chemi-epitaxy is used to guide self-assembly, then block copolymer domains can be precisely positioned on the substrate, but additional chemical patterning steps are required
Solution Approach 1:
The substrate is given different chemical properties in different regions - hydrophilic regions that attract hydrophilic blocks and hydrophobic regions that attract hydrophobic blocks. This local differentiation of chemical properties guides the block copolymer domains to self-assemble in specific locations with high precision
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
This approach allows for the formation of smaller feature sizes and improved resolution by guiding the self-assembly of block copolymers, enhancing the density and precision of patterns in semiconductor fabrication.
Implementation Method 1
a photo-sensitive component selected from (a) a photo-decomposable cross-linking agent, (b) a photo-base generator, or (c) a photo-decomposable base
Implementation Method 2
heating the layer of the radiation sensitive material to a temperature at or above the cross-linking reaction temperature to cross-link the cross-linkable polymer
Implementation Method 3
Block copolymers are compounds useful in nanofabrication because they may undergo an order-disorder transition on cooling below a certain temperature (order-disorder transition temperature ODT) resulting in phase separation of copolymer blocks
Implementation Method 4
In chemi-epitaxy, the self-assembly of block copolymer domains is guided by a chemical pattern (i.e., a chemical template) on the substrate. Chemical affinity between the chemical pattern and at least one of the types of copolymer blocks within the block copolymer chain may result in the precise placement (also referred to as "pinning") of one of the domain types onto a corresponding region of the chemical pattern on the substrate
Data Source
AI summary
A method of forming a layered substrate comprising a self-assembled material is provided. The method includes forming a first layer of material on a substrate, forming a layer of a radiation sensitive material on the first layer of material, imaging the layer of the radiation sensitive material with patterned light, heating the layer of the radiation sensitive material to a temperature at or above the cross-linking reaction temperature, developing the imaged layer, and forming the block copolymer pattern. The radiation sensitive material comprises at least one photo-sensitive component selected from (a) a photo-decomposable cross-linking agent, (b) a photo-base generator, or (c) a photo-decomposable base; and a cross-linkable polymer, wherein imaging by the patterned light provides a pattern defined by a first region having substantial portions of a decomposed photo-sensitive component surrounded by regions having substantial portions of intact photo-sensitive component.