Shadow Ring Irregular Pattern for Semiconductor Etching Mask Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor device manufacturing, the use of shadow rings helps prevent the etching of substrate edges, but existing methods can lead to roughening of the circumferential layer due to prolonged etching times for removing the hard mask, especially when no mask is formed in this region.
Innovation Solution
A method involving a shadow ring with an irregular pattern on its inner edge is used to form trenches or holes in the layer to be etched, allowing for efficient etching and subsequent quick removal of the hard mask, thereby minimizing roughening of the circumferential portion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a shadow ring is used to cover the circumferential portion during etching, then the substrate edge is protected from etching, but the hard mask removal time increases causing roughening of the circumferential layer
Solution Approach 1:
The shadow ring's inner circumferential edge is designed with an irregular pattern (protrusions and recesses) that adds dimensional complexity to the interface between the shadow ring and hard mask. This irregular pattern increases the contact surface area between the shadow ring and hard mask, thereby increasing the effective etching surface area of the hard mask during removal, which reduces the time required for hard mask removal while maintaining substrate edge protection.
2Object-generated harmful factors
If no hard mask is formed in the circumferential portion, then foreign matter generation is prevented, but the circumferential layer becomes vulnerable to roughening during etching
Solution Approach 1:
The shadow ring serves as an intermediary protective element that covers the circumferential portion during etching without requiring a hard mask to be formed in that region. The irregular pattern on the shadow ring's inner circumferential edge further enhances its protective function by increasing the surface area that interfaces with the hard mask, enabling faster removal while maintaining protection of the circumferential layer from roughening.
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 irregular pattern on the shadow ring increases the surface area of the hard mask, allowing for faster etching and reducing the time required to remove it, thus preventing roughening of the substrate's circumferential portion during the etching process.
Implementation Method 1
Since the shadow ring has the irregular pattern on the inner circumferential edge, the irregular pattern of the shadow ring is transferred to the etched region of the hard mask. The hard mask has, therefore, an increased surface area
Implementation Method 2
an electrode for generating plasma disposed in the process chamber
Implementation Method 3
a process chamber into which an etching gas is introduced
Data Source
AI summary
Aimed at suppressing roughening in a circumferential portion of a layer to be etched in the process of removing a hard mask formed thereon, an etching apparatus of the present invention has a process chamber, an electrode, a stage, and a shadow ring, wherein the process chamber allows an etching gas to be introduced therein; the electrode is disposed in the process chamber, and is used for generating plasma by ionizing the etching gas; the stage is disposed in the process chamber, onto which a substrate is disposed; the shadow ring has an irregular pattern on the inner circumferential edge thereof, and is disposed in the process chamber and placed above the stage 30, so as to cover a circumferential portion and an inner region adjacent thereto of the substrate in a non-contact manner.