PVD Target Backing Plate Cooling Channels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In physical vapor deposition (PVD) systems, high power density sputtering with high magnetic fields causes significant thermal gradients, leading to mechanical bowing and deformation of the sputtering target, which can result in mechanical stress, target fracture, and changes in plasma properties, affecting deposition rates and wafer quality. Additionally, inadequate cooling leads to re-sputtering and particle generation, reducing process yield.
Innovation Solution
A physical vapor deposition target assembly featuring a backing plate with channels or a cooling tube having bends to efficiently distribute cooling fluid, ensuring effective heat transfer and maintaining target stability by continuously replacing cooling fluid, thus reducing target temperature and preventing warping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If high power density sputtering with high magnetic fields is used, then deposition rate is improved, but target temperature rises causing mechanical bowing and deformation
Solution Approach 1:
The backing plate is divided into multiple cooling channels that segment the cooling fluid flow across different regions of the target, enabling distributed heat removal and preventing localized thermal accumulation that causes bowing
Solution Approach 2:
The cooling channels are strategically positioned to provide enhanced cooling at specific high-heat-generation zones on the target, creating non-uniform cooling intensity that matches the thermal load distribution and maintains target flatness
2Device complexity
If conventional cooling is used, then device complexity is minimized, but cooling effectiveness is insufficient to prevent target bowing
Solution Approach 1:
The cooling channels are integrated directly into the backing plate structure, merging the cooling system with the target holder and eliminating the need for separate external cooling apparatus, thus maintaining simplicity while achieving effective cooling
Solution Approach 2:
The cooling fluid acts as an intermediary medium that transfers heat from the target through the backing plate channels, enabling efficient thermal management without direct mechanical intervention or complex active cooling mechanisms
3Device complexity
If target temperature is not controlled, then process simplicity is maintained, but re-sputtering and particle generation increase reducing process yield
Solution Approach 1:
The cooling system operates autonomously with continuous cooling fluid circulation that automatically removes heat as it is generated, maintaining target temperature control without requiring external monitoring or adjustment mechanisms
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 solution provides a 25% reduction in target temperature, extends target life, and minimizes particle generation, improving process yield and maintaining optimal plasma conditions by ensuring efficient cooling and heat management.
Implementation Method 1
The sputtering target is cooled by contacting a target backing plate with cooling fluid
Implementation Method 2
channels including a plurality of bends defining a flow pattern including at least four rows and at least three bends
Data Source
AI summary
Physical vapor deposition target assemblies and methods of cooling physical vapor deposition targets are disclosed. An exemplary target assembly comprises a flow pattern including a plurality of rows and bends fluidly connected to an inlet end and an outlet end.