Polishing Pad Dressing Simulation with Diamond Particle Thrust Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for dressing polishing members in chemical-mechanical polishing apparatuses, such as those used for semiconductor wafers, face inaccuracies in simulating the distribution of the amount of polishing pad scraped off, leading to variations in polishing rate and potential polishing failures due to undesired undulations on the polishing surface.
Innovation Solution
A method that simulates the sliding distance of a diamond dresser on a polishing member, considering the thrusting depth and tilting of diamond particles, to determine accurate dressing conditions, ensuring a desired distribution of the amount scraped off, thereby improving the accuracy of the simulation and achieving a uniform polishing surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional simulation method is used to determine dressing conditions, then the process is simple, but the accuracy of the simulation is low leading to variations in polishing rate
Solution Approach 1:
The patent improves simulation accuracy by changing key parameters: incorporating thrusting depth of diamond particles, tilting angle of the dresser, and acceleration of dresser movement. These parameter changes transform the simulation from a simple sliding distance calculation to a comprehensive model that reflects actual dressing conditions, resolving the contradiction between simplicity and accuracy.
Solution Approach 2:
The patent replaces the conventional mechanical simulation approach with a corrected simulation model that accounts for physical realities like thrusting depth and tilting. This substitution transforms an inaccurate mechanical model into a more realistic representation without requiring complex experimental setups.
2Measurement precision
If the dresser moves at constant speed, then the control is simple, but the simulation accuracy is reduced due to ignoring acceleration effects
Solution Approach 1:
The patent incorporates acceleration as a dynamic parameter in the sliding distance calculation. By modifying the simulation to include acceleration effects during dresser movement, the model achieves higher accuracy in predicting the distribution of scraped polishing pad while maintaining manageable control through computational methods.
3Manufacturing precision
If the diamond particles are thrusting deeply into the polishing pad, then the dressing effect is strong, but the sliding distance simulation becomes inaccurate
Solution Approach 1:
The patent introduces thrusting depth as a correction parameter in the simulation. By accounting for how deeply diamond particles penetrate the polishing pad, the model adjusts the effective sliding distance to reflect actual dressing action, enabling accurate prediction of dressing uniformity even when thrusting depth varies.
4Measurement precision
If experiments are conducted to determine optimal dressing conditions, then the accuracy is high, but the time and labor required are excessive
Solution Approach 1:
The patent creates a virtual copy of the dressing process through simulation. Instead of conducting physical experiments to determine optimal conditions, the corrected simulation model replicates dressing scenarios computationally, providing accurate predictions without the time and labor costs of actual experimentation.
Solution Approach 2:
The patent replaces physical experimentation with a computational simulation system. By substituting mechanical experiments with a corrected mathematical model that incorporates thrusting depth, tilting, and acceleration, the system achieves experimental-level accuracy without the associated time and resource investments.
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 allows for more precise control of the polishing process, reducing variations in polishing rate and enhancing the consistency of the polishing surface, leading to improved polishing performance and reduced labor in determining optimal dressing conditions.
Implementation Method 1
a diamond dresser, having a number of diamond particles electrodeposited thereon, is used to dress (condition) the surface of the polishing member to regenerate fine irregularities on the surface of the polishing member
Implementation Method 2
a diamond dresser, having a number of diamond particles electrodeposited thereon
Data Source
AI summary
A method dresses a polishing member with a diamond dresser having diamond particles arranged on a surface thereof. The method includes determining dressing conditions by performing a simulation of a distribution of a sliding distance of the diamond dresser on a surface of the polishing member, and dressing the polishing member with the diamond dresser under the determined dressing conditions. The simulation includes calculating the sliding distance corrected in accordance with a depth of the diamond particles thrusting into the polishing member.