Silicon Carbide Ceramic Substrate Surface Particle Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electrostatic chuck devices, the friction between the plate-shaped sample and the projection shapes leads to the generation of dielectric material fragments, known as particles, which can cause variations in etching and contamination during plasma processes.
Innovation Solution
A ceramic substrate with a dielectric material containing silicon carbide particles is used, where the number of particles on the surface is reduced through methods like heat treatment, laser irradiation, or acid treatment to minimize particle generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If projection shapes are formed on the substrate surface to enable cooling gas flow and temperature control, then temperature control capability is improved, but friction between the sample and projection shapes increases, leading to particle generation
Solution Approach 1:
The patent applies local quality by creating projection portions with specific localized properties on the substrate surface. These projections have differentiated characteristics: they provide cooling gas flow paths for temperature control while having controlled surface properties (through material selection and surface treatment) to minimize friction-induced particle generation. The projection portions are not uniform but have tailored local characteristics to balance thermal management and particle suppression.
Solution Approach 2:
The patent employs parameter changes by controlling the physical and chemical parameters of the projection portions. This includes adjusting the material composition (dielectric material with specific properties), surface roughness parameters, and geometric parameters of the projections. By optimizing these parameters, the substrate achieves both effective cooling gas flow for temperature control and reduced friction to minimize particle generation during plasma processes.
2Ease of operation
If the substrate surface is processed to create projection shapes for sample mounting, then sample fixation capability is improved, but the friction from sample contact causes dielectric material fragments to fall off, increasing particle contamination
Solution Approach 1:
The projection portions are designed with local quality differentiation to simultaneously achieve strong sample fixation and minimize particle generation. The localized structural features provide mechanical interlocking for secure mounting while the surface properties (controlled through material selection and processing) reduce friction-induced material degradation. This localized optimization allows the substrate to perform both functions effectively.
Solution Approach 2:
The patent utilizes composite material principles by employing a dielectric material with specific compositional characteristics for the substrate and projection portions. The material composition is tailored to provide both the mechanical strength needed for sample fixation and the surface properties that minimize friction and particle generation. The composite nature of the material allows balancing of competing requirements for fixation strength and particle suppression.
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 approach effectively suppresses the generation of particles, maintaining the electrical characteristics and ensuring clean processes in semiconductor manufacturing.
Implementation Method 1
a step of heat-treating the base material at a temperature of 900° C. or higher and 1300° C. or lower in a chamber for treatment
Implementation Method 2
a step of performing heat treatment by irradiating a surface of the base material on which the projection portions have been formed, with laser light
Implementation Method 3
a step of acid-treating a surface of the base material on which the projection portions are formed
Implementation Method 4
an electrostatic attraction electrode that generates an electrostatic force (Coulomb's force) between a substrate having one main surface serving as a mounting surface on which a wafer is placed and the wafer placed on the mounting surface
Implementation Method 5
the plate-shaped sample can be cooled by causing a cooling gas to flow in the space between the projection portions, and thus the temperature of the plate-shaped sample can be controlled
Data Source
AI summary
A ceramic substrate made of a dielectric material including silicon carbide particles, which is used as a forming material, in which the number of the silicon carbide particles per unit area on the surface of the substrate is smaller than the number of the silicon carbide particles per unit area in a cross section of the substrate.