PVD Deposition Ring Barrier Structure for Wafer Edge Arcing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The PVD process faces arcing issues due to contamination or residues on the wafer surface, which current methods attempt to mitigate by cleaning, extending degassing time, or reducing discharge power, but these approaches increase process time, energy consumption, or reduce throughput.
Innovation Solution
A deposition ring with a barrier structure is used to alter electron density distribution, preventing the formation of a path from the wafer edge to the target through electrons or ions in the plasma, thereby mitigating arcing without reducing throughput or increasing energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If cleaning methods are used to mitigate arcing issues, then arcing is reduced, but process time increases
Solution Approach 1:
The barrier structure is pre-installed on the deposition ring before the PVD process begins. This preliminary configuration creates an electron density barrier that prevents arcing during the deposition process, eliminating the need for post-cleaning operations and reducing overall process time while maintaining reliability
2Reliability
If degassing time is extended to mitigate arcing issues, then arcing is reduced, but productivity decreases
Solution Approach 1:
The barrier structure acts as an intermediary element between the plasma and the wafer surface. It modifies the electron density distribution in the plasma sheath region, creating a protective barrier that prevents arcing without requiring extended degassing time, thereby maintaining high productivity and throughput
3Reliability
If discharge power is reduced to mitigate arcing issues, then arcing is reduced, but energy efficiency worsens
Solution Approach 1:
The barrier structure creates a localized modification in electron density distribution at the wafer edge region where arcing typically occurs. This localized quality change allows the plasma to maintain high discharge power and energy efficiency in the bulk region while preventing arcing at the specific location where the barrier is present, improving overall energy efficiency
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 barrier structure effectively reduces electron density around the wafer edge, minimizing arcing incidence without the need for additional cleaning or process adjustments, thus maintaining throughput and reducing costs.
Implementation Method 1
A deposition ring with a barrier structure is used to alter electron density distribution, preventing the formation of a path from the wafer edge to the target through electrons or ions in the plasma
Implementation Method 2
The plasma physically dislodges or erodes (sputters) atoms or molecules from the reaction surface of the PVD target into a vapor of the target material, as a result of collision with high-energy particles (ions) of the plasma
Implementation Method 3
The vapor of sputtered atoms or molecules of the target material is transported to the substrate through a region of reduced pressure and condenses on the substrate, forming the thin film of the target material
Data Source
AI summary
An apparatus for PVD is provided. The apparatus includes a chamber, a pedestal disposed in the chamber to accommodate a wafer, and a ring. The ring includes a ring body having a first top surface and a second top surface, and a barrier structure disposed between the first top surface and the second top surface. The barrier structure can further include at least a first portion and a second portion separated from each other. The second vertical distance is equal to or greater than the first vertical distance.