Electrostatic Chuck Surface Structure for Edge Film Thickness Tuning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor processing systems face challenges in achieving uniform film thickness across substrates due to non-uniform deposition rates at the edge regions, which can lead to yield issues and film uniformity problems during etching and polishing operations.
Innovation Solution
The substrate support assemblies feature a high density of protrusions on the support surface, arranged in concentric annular rings with varying densities to alter the electric field distribution, allowing for increased film thickness at edge regions through controlled chucking voltage adjustments, thereby enhancing film uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional substrate support surfaces are used with uniform structure, then the manufacturing process is simple, but the film thickness uniformity across the substrate deteriorates due to edge non-uniformity
Solution Approach 1:
The substrate support surface is divided into multiple regions with different protrusion densities. The outer region has a higher density of protrusions compared to the inner region, creating local variations in electric field strength and plasma density. This local quality differentiation compensates for edge non-uniformity by enhancing deposition at the wafer edges, thereby achieving uniform film thickness across the entire substrate surface.
2Manufacturing precision
If the protrusion density is increased at the outer region, then the film thickness uniformity improves, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The substrate support surface is segmented into distinct regions (inner region and outer region) with different protrusion densities. This segmentation allows for optimized deposition characteristics in each region while managing manufacturing complexity through modular design approaches.
Solution Approach 2:
The protrusion density parameter is varied across different regions of the substrate support surface. By changing this geometric parameter from uniform to non-uniform distribution, the patent achieves improved film thickness uniformity without requiring fundamental changes to the overall device architecture or manufacturing process.
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
This approach increases film thickness at edge regions, leading to a more uniform film thickness profile across the substrate, which is particularly beneficial for substrates undergoing etching and polishing operations with varying etch rates.
Implementation Method 1
clamping a semiconductor substrate to a substrate support surface of an electrostatic chuck using a chucking voltage
Implementation Method 2
performing one or more deposition operations on the semiconductor substrate
Data Source
AI summary
Exemplary substrate support assemblies may include an electrostatic chuck body that defines a substrate support surface. The substrate support surface may define a plurality of protrusions that extend upward from the substrate support surface. A density of the plurality of protrusions within an outer region of the substrate support surface may be greater than in an inner region of the substrate support surface. The substrate support assemblies may include a support stem coupled with the electrostatic chuck body. The substrate support assemblies may include an electrode embedded within the electrostatic chuck body.