Iodine-Containing Underlayer for EUV Lithography
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current EUV lithography technologies face challenges in resist sensitivity and throughput due to low EUV light absorption cross-section in traditional resist materials, leading to higher power requirements and noise-induced line edge roughness.
Innovation Solution
A coating composition incorporating an iodine-containing crosslinkable polyester polymer and crosslinker with an acid catalyst is applied as an underlayer, enhancing EUV light absorption and providing a higher dry etch rate, thereby improving resist sensitivity and pattern fidelity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional resist materials are used in EUV lithography, then the process can be maintained with conventional materials, but the EUV light absorption cross-section is low leading to reduced resist sensitivity and increased power requirements
Solution Approach 1:
The patent changes the chemical composition parameters of the underlayer material by incorporating iodine-containing compounds (such as iodine-containing polymers, monomers, or small molecules) into the underlayer formulation. This compositional parameter change increases the EUV light absorption cross-section from typical values of conventional materials to significantly higher values, thereby improving resist sensitivity and reducing the power requirements of the EUV light source.
Solution Approach 2:
The patent creates a composite underlayer material system by combining iodine-containing compounds with other underlayer components (such as polymers, solvents, and additives). This composite approach allows the underlayer to exhibit enhanced EUV absorption properties while maintaining the necessary mechanical and chemical properties for effective underlayer functionality, thus resolving the contradiction between absorption enhancement and material performance.
2Productivity
If traditional underlayer compositions are used, then material compatibility is maintained, but dry etch rate is insufficient affecting throughput
Solution Approach 1:
The patent modifies the chemical composition parameters of the underlayer by introducing iodine-containing compounds with specific molecular structures and functional groups that are known to enhance dry etch rates. These parameter changes in composition enable the underlayer to be removed more rapidly during the dry etch process, directly increasing productivity and reducing cycle time without compromising the underlayer's protective functions during lithography.
3Illumination intensity
If higher power sources are used to compensate for low absorption, then EUV light intensity is increased, but noise-induced line edge roughness increases
Solution Approach 1:
The patent introduces the underlayer as an intermediary component between the EUV light source and the photoresist. This intermediary layer with high iodine content acts as a mediator that enhances light absorption and generates secondary electrons that improve photoresist sensitivity. By using this intermediary, the system can achieve the necessary absorption at lower light intensities, thereby avoiding the noise-induced line edge roughness that would result from using higher power sources directly.
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 iodine-rich underlayer composition significantly increases EUV photoresist sensitivity and dry etch rate, reducing the need for higher power sources and minimizing line edge roughness, thus enhancing the overall performance of EUV lithography processes.
Implementation Method 1
Iodine has remarkably high EUV light absorption cross-section. It has been shown that EUV light absorption cross-section and secondary electron generation yield are critical factors for EUVL sensitivity.
Implementation Method 2
a crosslinkable polyester polymer including an isocyanurate group and a crosslinkable group; a crosslinker; and an acid catalyst
Data Source
AI summary
A coating composition comprising a crosslinkable polyester polymer comprising an isocyanurate group and a crosslinkable group; a crosslinker; and an acid catalyst, wherein at least one of the crosslinkable polyester polymer and the crosslinker comprises an iodine-containing polymer.