Magnetic Shielding in Copper PVD Chambers for Uniform Deposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Copper atoms during physical vapor deposition (PVD) are susceptible to redirection by external noise such as RF and EM radiation, leading to non-uniform deposition and reduced conductivity and lifetime of BEOL and MEOL conductive structures.
Innovation Solution
Implementing a magnetic shield with a thickness of 0.1 mm to 10 mm to insulate the deposition chamber from RF and EM noise, ensuring uniform copper deposition and reducing hardware failure susceptibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If copper deposition is performed using PVD without magnetic shielding, then the deposition process can proceed without additional components, but the copper atoms are redirected by external RF and EM noise leading to non-uniform deposition
Solution Approach 1:
A magnetic shield is introduced as an intermediary component between the external RF/EM noise environment and the copper deposition chamber. The magnetic shield acts as a mediator that blocks or attenuates the harmful electromagnetic radiation, preventing it from interfering with the copper atom trajectories during PVD, thereby ensuring uniform deposition without requiring fundamental changes to the deposition process itself.
Solution Approach 2:
The harmful RF and EM noise is extracted or removed from the deposition environment by implementing magnetic shielding. The shield selectively extracts the detrimental electromagnetic components from the chamber environment while allowing the beneficial copper vapor to reach the substrate, thus achieving uniform deposition by eliminating the interfering external factors.
2Reliability
If no magnetic shield is used, then the device structure remains simple, but copper atoms are susceptible to redirection leading to reduced conductivity and lifetime of conductive structures
Solution Approach 1:
The magnetic shield serves as a protective intermediary that isolates the copper deposition process from external RF and EM interference. By placing the shield around the chamber or at strategic positions, it mediates the interaction between external noise and copper atoms, ensuring reliable conductive structure formation with improved conductivity and lifetime.
Solution Approach 2:
The magnetic shield provides beforehand cushioning or protection against the harmful effects of RF and EM noise before the copper deposition occurs. By pre-establishing the shielded environment, the copper atoms are protected from redirection forces during the entire deposition process, ensuring formation of reliable conductive structures with enhanced durability and conductivity.
3Manufacturing precision
If magnetic shield thickness is increased to improve noise insulation, then uniformity of deposition improves, but device complexity and manufacturing cost increase
Solution Approach 1:
The magnetic shield thickness is optimized by changing the physical parameter of the shield design. Instead of using excessive thickness, the patent identifies an optimal range (0.1 mm to 10 mm) that provides sufficient RF and EM noise attenuation while maintaining reasonable device complexity. This parameter optimization achieves uniform copper deposition without unnecessary complexity or cost.
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
Enhances the uniformity of BEOL and MEOL conductive structure formation, improving conductivity and extending the lifetime of electronic devices.
Implementation Method 1
a magnetic shield adjacent to the chamber and configured to reduce electromagnetic noise within the chamber
Implementation Method 2
at least one electromagnet and at least one flow optimizer that are configured to direct copper ions from a copper target onto a wafer
Implementation Method 3
at least one electromagnet and at least one flow optimizer that are configured to direct copper ions from a copper target onto a wafer
Implementation Method 4
Copper atoms during physical vapor deposition (PVD) are susceptible to redirection by external noise
Data Source
AI summary
A magnetic shield reduces external noise in a chamber including a target and at least one electromagnet for copper physical vapor deposition (PVD). The shield may have a thickness in a range from approximately 0.1 mm to approximately 10 mm to provide sufficient protection from radio frequency and other electromagnetic signals. As a result, copper atoms in the chamber undergo less re-direction from external noise. Additionally, even when hardware failure occurs during PVD (e.g., an electromagnet malfunctions, a wafer stage is not level, and/or a flow optimizer induces too much shift, among other examples), the copper atoms are less susceptible to small re-directions from external noise. As a result, back end of line (BEOL) and/or middle end of line (MEOL) conductive structures are formed in a more uniform manner, which increases conductivity and improves lifetime of an electronic device including the BEOL and/or MEOL conductive structures.