Irregular Silica Polishing Particles for Scratch-Free Substrate Smoothing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional silica-based polishing particles face challenges in achieving a high polishing rate while preventing particle residues on substrates, with existing solutions either resulting in scratches or inadequate surface smoothness due to issues with particle hardness, shape, and impurity content.
Innovation Solution
A silica-based polishing particle with a three-dimensional polycondensation structure, having an average particle diameter of 5 to 300 nm, an aspect ratio of 1.20 to 5.00, and a carbon content of 0.005% to 0.50% by mass, which is irregularly shaped and has a low number of alkoxy groups, reducing particle residues and enhancing polishing efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional spherical silica polishing particles are used, then the polishing process is simple, but scratches are generated on the substrate surface and particle residues remain
Solution Approach 1:
The patent applies the reverse of spheroidality by deliberately creating irregularly shaped particles with aspect ratios of 1.05 to 1.40 instead of conventional spherical shapes. This irregular shape increases mechanical action during polishing, improving substrate surface smoothness and reducing scratches while maintaining reasonable manufacturing complexity through controlled hydrolysis and condensation processes
2Productivity
If high SiO2 content polishing particles are used, then polishing rate increases, but scratches are more likely to be generated
Solution Approach 1:
The patent optimizes the SiO2 content parameter to a specific range of 80 to 95% by mass, balancing hardness for high polishing rate with controlled irregular shape (aspect ratio 1.05-1.40) to prevent scratches. This parameter optimization resolves the contradiction by finding the optimal point where both polishing rate and surface smoothness are maximized
3Productivity
If polishing particles with high hardness are used, then polishing rate increases, but particle residues remain on the substrate
Solution Approach 1:
The patent creates particles with non-uniform local properties through controlled hydrolysis and condensation, resulting in irregular shapes with aspect ratios of 1.05 to 1.40. This local structural variation prevents particles from embedding into the substrate, reducing particle residues while maintaining high polishing rate through the harder, irregular surfaces
4Productivity
If irregularly shaped particles with high aspect ratio are used, then polishing rate increases, but particle residues are more likely to remain
Solution Approach 1:
The patent optimizes the aspect ratio parameter to a specific range of 1.05 to 1.40, which provides sufficient irregularity for high polishing rate while avoiding excessive irregularity that would cause particle embedding and residues. This precise parameter control resolves the contradiction by finding the optimal aspect ratio range
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 silica-based polishing particle provides a high polishing rate with reduced particle residues, making it suitable for primary polishing in semiconductor integrated circuits, ensuring both high performance and surface smoothness.
Implementation Method 1
The abrasive used in the CMP method is typically composed of: a spherical polishing particle consisting of a metal oxide such as silica and alumina
Implementation Method 2
a silica-based particle with a three-dimensional polycondensation structure containing an alkoxy group
Data Source
AI summary
Provided is a silica-based polishing particle, particularly suitable for primary polishing, which provides a high polishing rate on the surface of a substrate and which prevents particle residues on the substrate after polishing, and an abrasive including the silica-based polishing particle. A silica-based polishing particle with a three-dimensional polycondensation structure containing an alkoxy group, wherein the particle has an average particle diameter (d) of 5 to 300 nm, an aspect ratio of more than 1.20 and 5.00 or less, and a carbon content of 0.005% by mass or more and less than 0.50% by mass.