Ring-Shaped Magnet Layout for Uniform Plasma Etching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor fabrication processes face challenges in achieving uniform plasma density, leading to non-uniform etch processes and degraded performance in semiconductor device manufacturing.
Innovation Solution
The use of a ring-shaped magnet above an electrostatic chuck, with an inner radius ranging from one-half to one-fourth of the substrate radius, to generate a magnetic field that corrects the plasma density distribution, ensuring uniformity across the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional plasma generation method is used without a magnet, then the device complexity is low, but the plasma density uniformity is poor leading to non-uniform etch processes
Solution Approach 1:
The patent applies local quality by positioning a magnet with specific geometric parameters (inner radius R1 and outer radius R2) above the electrostatic chuck to create a localized magnetic field in the intermediate region of the substrate. This localized field modifies plasma density distribution specifically in the region where it is needed, without requiring a complete redesign of the entire plasma generation system.
Solution Approach 2:
The patent utilizes parameter changes by controlling the magnetic field strength through adjustable magnetic field generating means and optimizing the geometric parameters of the magnet (radii R1 and R2) to achieve desired plasma density uniformity. The relationship between magnetic field parameters and plasma density distribution is exploited to resolve the contradiction.
2Manufacturing precision
If the magnet is positioned close to the substrate to effectively influence plasma density, then the plasma density uniformity improves, but the risk of arcing increases
Solution Approach 1:
The patent controls the vertical position parameter of the magnet relative to the substrate and optimizes the magnetic field strength parameter to achieve effective plasma density control without causing arcing. By carefully adjusting these parameters, the system maintains beneficial plasma uniformity while avoiding harmful discharge effects.
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 configuration results in highly uniform plasma density, enhancing etch uniformity and improving the overall performance of semiconductor device fabrication.
Implementation Method 1
seating a substrate having a substrate radius on an electrostatic chuck
Implementation Method 2
applying first radio-frequency power to the electrostatic chuck to induce plasma in a region at least above the electrostatic chuck
Implementation Method 3
generating a magnetic field in the region at least above the electrostatic chuck using a magnet having a ring-shape and disposed above the electrostatic chuck by applying second radio-frequency power to the magnet
Data Source
AI summary
A method of fabricating a semiconductor device include; seating a substrate having a substrate radius on an electrostatic chuck, applying first radio-frequency power to the electrostatic chuck to induce plasma in a region at least above the electrostatic chuck, and generating a magnetic field in the region at least above the electrostatic chuck using a magnet having a ring-shape and disposed above the electrostatic chuck by applying second radio-frequency power to the magnet, wherein the magnet has an inner radius ranging from about one-half to about one-fourth of the substrate radius.