Resist Underlayer Composition for Planarizing Multi-Level Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional resist underlayer film-forming compositions face issues with insufficient filling in irregular patterns, poor reflow properties, and dimensional alterations due to thermal shrinkage, leading to suboptimal planarization and reflection effects in semiconductor device lithography.
Innovation Solution
A resist underlayer film-forming composition comprising a copolymer with specific repeating structural units and optional photo-crosslinking agents, surfactants, and organic solvents, which can be thermally cured at high temperatures without light exposure to achieve high reflow properties and improved antireflection effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a resist underlayer film-forming composition containing a polymer having a thermally crosslinkable functional group (e.g., hydroxy group) and a crosslinking agent is heated for filling into irregular patterns, then the crosslinking reaction proceeds to increase viscosity, but this leads to insufficient filling into the interior of the pattern on the substrate
Solution Approach 1:
The patent changes the crosslinking mechanism from thermal to photo-initiated by incorporating a photopolymerization initiator. This allows the composition to maintain low viscosity during heating for filling, then rapidly crosslink upon photoirradiation to achieve both good filling and strong adhesion without the viscosity increase problem during the filling process
2Temperature
If a resist underlayer film is formed through heating at a temperature of 180° C. or higher, then the composition is gradually thermally cured, but this causes poor reflow properties
Solution Approach 1:
The patent replaces thermal curing with photo-curing by incorporating a photopolymerization initiator. This substitution allows the composition to be heated to high temperatures for filling without gradual thermal crosslinking, maintaining good reflow properties while achieving the desired filling effect through photoirradiation after heating
3Reliability
If a resist underlayer film-forming composition contains a polymer having a cationic polymerizable reactive group and an acid generator, then the composition is cured through combination of photoirradiation and heating, but this causes cumbersome processes
Solution Approach 1:
The patent extracts and eliminates the heating step from the curing process by using a photopolymerization initiator that enables curing through photoirradiation alone. This simplifies the process from a two-step photoirradiation and heating sequence to a single photoirradiation step, reducing process complexity while maintaining effective curing
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 effectively forms a flat, planarized film on multi-level substrates with enhanced reflow properties and antireflection effects, simplifying the production process and improving work efficiency.
Implementation Method 1
a copolymer having a repeating structural unit of the following Formula (1) and/or a repeating structural unit of the following Formula (2)... R1 is a functional group of Formula (3)... Q1 and Q2 are each independently a hydrogen atom or a C1-5 alkyl group
Implementation Method 2
reflection of exposure light coming from a substrate onto a resist layer causes deformed pattern edges... forming a cured film with advanced reflection effect
Data Source
AI summary
A resist underlayer film-forming composition revealing high reflow properties while applying and heating the composition on a substrate, allowing a flat application on a multi-level substrate thus forming a flat film. The composition includes a copolymer having a repeating structural unit of the following Formula (1) and/or a repeating structural unit of the following Formula (2) and an organic solvent:(in Formulae (1) and (2), R1 is a functional group of Formula (3); in Formula (3), Q1 and Q2 are each independently a hydrogen atom or a C1-5 alkyl group, and * is a dangling bond to an oxygen atom; and in Formula (2), X1 is a C1-50 organic group, and i and j are each independently 0 or 1).