Bevel Plasma Treatment for Copper Edge Clean
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in semiconductor and flat panel display manufacturing is the difficulty in removing unwanted copper deposits at the bevel edge of substrates, which leads to particle issues and contamination, affecting process yield and throughput.
Innovation Solution
A method involving plasma treatment to convert copper at the bevel edge into a copper compound that can be removed with high etch selectivity using wet or dry etching, allowing precise spatial control and preventing copper etching fluid from splashing onto device regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If wet etching is used to remove copper deposits at the bevel edge, then removal effectiveness is improved, but copper etching fluid may splash onto device regions causing defects and thinning of copper films
Solution Approach 1:
The substrate processing is divided into separate zones: a first portion containing the device region and a second portion containing the bevel edge. The plasma treatment is applied selectively to the second portion, spatially segmenting the treatment area from the device region. This segmentation prevents etching fluid from needing to contact the device region while still achieving effective copper removal at the bevel edge.
Solution Approach 2:
Different treatment approaches are applied to different regions of the substrate. The bevel edge region receives plasma treatment to convert copper to copper compound, while the device region is protected from etching fluid exposure. This local differentiation of treatment quality ensures effective copper removal where needed while preventing harmful fluid splashing on sensitive device areas.
2Reliability
If manual wet cleaning is used to remove copper deposits, then particle contamination is reduced, but manufacturing throughput decreases due to manual intervention
Solution Approach 1:
The manual mechanical cleaning process is replaced with an automated plasma treatment system. The plasma reactor automatically treats the bevel edge region, converting copper to copper compound without requiring manual intervention. This substitution maintains effective particle contamination control while enabling continuous automated processing that improves manufacturing throughput.
Solution Approach 2:
The physical and chemical state of copper at the bevel edge is changed through plasma treatment, converting it from metallic copper to copper compound. This parameter change enables subsequent easy removal by wet etching while maintaining automated continuous processing, thereby improving both reliability and productivity simultaneously.
3Manufacturing precision
If plasma treatment is applied to convert copper to copper compound, then etch selectivity is improved, but process complexity increases due to additional processing steps
Solution Approach 1:
The plasma treatment is applied selectively only to the bevel edge region (second portion) of the substrate, while the device region (first portion) is protected. This spatial segmentation allows the additional plasma treatment step to be performed without requiring complex masking or protection of the entire substrate, thereby improving etch selectivity while minimizing the increase in overall process 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
This approach improves process yield by enabling precise removal of copper at the bevel edge, reducing particle contamination and maintaining device integrity, while allowing continuous manufacturing without manual wet cleaning.
Implementation Method 1
plasma is often employed... generating a treatment plasma near the bevel edge of the substrate to convert the copper film on the bevel edge of the substrate to a copper compound
Implementation Method 2
convert the copper at bevel edge to a copper compound that can be wet etched with a fluid at a high etch selectivity in comparison to copper
Data Source
AI summary
The various embodiments described in the specification provide improved mechanisms of removal of unwanted deposits on the bevel edge to improve process yield. The embodiments provide apparatus and methods of treating the bevel edge of a copper plated substrate to convert the copper at the bevel edge to a copper compound that can be wet etched with a fluid at a high etch selectivity in comparison to copper. In one embodiment, the wet etch of the copper compound at high selectivity to copper allows the removal of the non-volatile copper at substrate bevel edge in a wet etch processing chamber. The plasma treatment at bevel edge allows the copper at bevel edge to be removed at precise spatial control to about 2 mm or below, such as about 1 mm, about 0.5 mm or about 0.25 mm, to the very edge of substrate. In addition, the apparatus and methods described above for bevel edge copper removal do not have the problems of copper etching fluid being splashed on the device regions to cause defects and thinning of copper films. Therefore, device yield can be greatly improved.