AlN Wafer Support Surface Layer to Prevent Dross Particles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor manufacturing apparatus members with laser marks on AlN ceramic substrates can form dross, leading to particle occurrence during wafer processing.
Innovation Solution
An AlN ceramic substrate with a surface layer region having a higher oxygen content rate than the base material region, preferably blackened, and a mass ratio O/N higher than the base material region, is used to prevent particle formation by increasing hardness and avoiding dross formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If linearly extending laser marks are provided on the lateral surfaces of the small projections to prevent particle occurrence, then particles are prevented from occurring due to removal of crystal particles, but the laser marks form dross which may cause the occurrence of particles
Solution Approach 1:
The invention changes the physical-chemical parameters of the AlN ceramic substrate surface by creating a surface layer region with higher oxygen content rate (at least 2.0 times the base material region) and different mass ratios (O/N and Al/N). This parameter change modifies the surface properties to increase hardness and prevent dross formation during laser marking, thereby eliminating the harmful effect while maintaining the beneficial particle prevention effect.
Solution Approach 2:
The invention creates a composite structure within the AlN ceramic substrate by forming a surface layer region with distinct compositional characteristics (higher oxygen content, different O/N and Al/N ratios) compared to the base material region. This composite structure provides enhanced surface hardness and dross-free properties while maintaining the bulk material's functional characteristics.
2Reliability
If the surface of the AlN ceramic substrate is hardened to prevent particle occurrence, then particle generation is reduced, but the surface may become too hard affecting wafer placement uniformity
Solution Approach 1:
The invention applies local quality by creating a surface layer region with enhanced hardness only in specific areas (at least part of the area provided with no projection), while maintaining the base material region's original properties. The surface layer region has an oxygen content rate at least 2.0 times that of the base material region, providing localized hardness enhancement that prevents particle generation without affecting overall wafer placement uniformity.
3Temperature
If the surface layer region is blackened to absorb heat and release radiation for uniform wafer temperature, then thermal uniformity is improved, but the manufacturing process becomes more complex
Solution Approach 1:
The invention merges multiple functions into the surface layer region formation process. The same laser processing that creates the surface layer region with higher oxygen content and different mass ratios also blackens the surface to enhance heat absorption and radiation. This combined approach achieves both structural modification (hardness enhancement) and functional modification (thermal management) in a single process step, avoiding additional complexity.
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 solution effectively prevents particle occurrence during wafer processing by enhancing the hardness of the surface layer and ensuring no dross is present, maintaining a uniform wafer temperature and reducing wear on projections.
Implementation Method 1
an oxygen content rate of the surface layer region is higher than an oxygen content rate of the base material region
Implementation Method 2
the surface layer region is preferably blackened. In this manner, the surface layer region is likely to absorb heat
Implementation Method 3
thus radiation heat is likely to be released
Implementation Method 4
the linearly extending laser marks on the lateral surfaces of the small projections are so-called dross (part of a material which is once melted and solidified)
Data Source
AI summary
A member for semiconductor manufacturing apparatus of the present invention includes an AlN ceramic substrate with a surface provided with projections for wafer placement. At least part of an area, provided with no projection, of the AlN ceramic substrate has a surface layer region from the surface to a predetermined depth, and a base material region below the surface layer region. The predetermined depth is 5 μm or less. The oxygen content rate of the surface layer region is higher than the oxygen content rate of the base material region.