Post-CMP Rinse Composition for Wafer Residue Removal
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Solution Overview
Problem
Conventional post-CMP cleaning processes are inadequate in removing contaminants from polished semiconductor wafers, leading to defects and diminished device performance in advanced node semiconductor manufacturing.
Innovation Solution
A polisher rinse composition comprising a surface roughness controller, pH adjuster, particle dispersion agent, chelating agent, and corrosion inhibitor, applied directly on the polishing tool to clean the substrate after CMP, followed by a brief DI water rinse, effectively removes residues and contaminants without abrasive particles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional post-CMP cleaning solutions are used, then the cleaning process is simple, but contaminants are not adequately removed from the wafer surface
Solution Approach 1:
The patent applies composite materials by formulating a cleaning composition that integrates multiple functional components (surfactants, chelating agents, oxidizing agents, and abrasive particles) into a single synergistic formulation. This composite approach enables the composition to simultaneously perform emulsification, chelation, oxidation, and mechanical removal functions, thereby achieving adequate contaminant removal while maintaining reasonable process simplicity.
Solution Approach 2:
The cleaning composition is designed with multi-functionality to address various types of contaminants (organic residues, inorganic particles, metal ions) through a single application. The composition includes surfactants for emulsification, chelating agents for metal ion removal, oxidizing agents for organic residue breakdown, and abrasive particles for mechanical cleaning, allowing one composition to perform multiple cleaning tasks that previously required separate processes.
2Reliability
If deionized water rinse is used after CMP, then the process is simple and fast, but water-miscible components and byproducts remain on the wafer surface
Solution Approach 1:
The cleaning composition is applied immediately after the CMP process while the wafer is still on the polishing pad, performing preliminary cleaning before the wafer is transferred to separate rinsing equipment. This preliminary action allows the composition to emulsify and remove contaminants in situ, reducing the need for extended subsequent rinsing time and improving overall process efficiency.
Solution Approach 2:
The cleaning composition acts as an intermediary between the CMP process and final rinsing. It mediates the transition by chemically modifying contaminants (emulsifying organics, chelating metals, oxidizing residues) into forms that are more easily removed during subsequent brief DI water rinses, thereby achieving thorough cleaning without excessive rinsing time.
3Reliability
If brush scrubber or spin rinse dry apparatus is used for P-CMP cleaning, then the cleaning mechanism is established, but contaminants are still not adequately removed in advanced node manufacturing
Solution Approach 1:
The patent applies parameter changes by modifying the chemical parameters of the cleaning composition (pH, ionic strength, surfactant concentration, oxidizing potential) to optimize its effectiveness against advanced node contaminants. The composition is formulated with specific pH ranges and component concentrations that enhance its ability to remove ultra-fine particles and organic residues that conventional cleaners cannot adequately address.
Solution Approach 2:
The cleaning composition integrates multiple functional components (surfactants, chelating agents, oxidizing agents, and abrasive particles) into a single synergistic formulation. This composite approach enables the composition to simultaneously perform emulsification, chelation, oxidation, and mechanical removal functions, thereby achieving adequate contaminant removal while maintaining reasonable process simplicity.
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 enhances wafer surface cleanliness, reduces defects, and ensures optimal device performance by effectively removing post-CMP residues and contaminants, thereby improving yield in semiconductor manufacturing.
Implementation Method 1
at least one chelating agent
Implementation Method 2
at least one particle dispersion agent
Implementation Method 3
at least one oxidizing agent
Data Source
AI summary
This disclosure relates to a composition that includes at least one surface roughness controller; at least one pH adjuster; at least one particle dispersion agent; at least one chelating agent; at least one corrosion inhibitor; and an aqueous solvent, in which the composition has a pH of from about 7 to about 14.