CMP Hot Spot Correction via Rotational Orientation Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional chemical mechanical polishing (CMP) processes cannot determine the rotational orientation of a substrate relative to the carrier head, making it impossible to selectively target and treat hot spots during the polishing process.
Innovation Solution
A method is introduced that involves determining the location of a hot spot on the substrate and its rotational orientation relative to the carrier head, allowing for targeted treatment by pulsing a second fluid onto the polishing pad at a specific radial position to interact with the hot spot.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional CMP processes are used without rotational orientation determination, then the polishing process can proceed continuously, but the location of hot spots relative to the carrier head remains unknown and cannot be selectively targeted
Solution Approach 1:
The system performs preliminary detection of the substrate's rotational orientation and hot spot locations before the polishing process begins. This preliminary action enables the control system to pre-calculate the optimal fluid delivery positions and timing, allowing selective hot spot treatment without disrupting the continuous polishing operation.
Solution Approach 2:
The system implements a feedback mechanism where the detected rotational orientation and hot spot locations are continuously monitored and used to adjust the fluid delivery arm's positioning and pulsing timing. This closed-loop control ensures that remedial fluid is delivered precisely to the locations corresponding to hot spots on the substrate surface.
2Manufacturing precision
If a second fluid delivery arm is added to pulse fluid at specific radial positions for hot spot treatment, then selective hot spot treatment becomes possible, but the device complexity increases
Solution Approach 1:
The second fluid delivery arm is integrated into the existing polishing system architecture, sharing common components such as the platen, polishing pad, and control system. The fluid delivery arm can perform multiple functions: delivering polishing slurry during normal operation and pulsing remedial fluid at specific radial positions for hot spot treatment, thereby reducing overall system complexity.
Solution Approach 2:
The fluid delivery arm is designed with dynamic positioning capabilities, allowing it to move to different radial positions on the polishing pad surface during the polishing process. This dynamic adjustment enables the system to target specific hot spot locations while maintaining a relatively simple mechanical structure compared to having multiple fixed delivery systems.
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 enables precise treatment of hot spots while maintaining the polishing rate of other areas, improving the overall planarization process and reducing imperfections in the substrate.
Implementation Method 1
The polishing pad and the carrier head each rotate at a constant rotational speed and the abrasive slurry removes material from one or more of the layers
Data Source
AI summary
A method of processing a substrate, includes placing a front surface of a substrate disposed in a carrier head on a polishing surface of a pad. The method further includes delivering a first fluid onto the polishing surface using a first fluid delivery arm. The method further includes determining a location of a hot spot on the front surface. The method further includes determining a rotational orientation of the substrate relative to the carrier head. The method further includes treating the hot spot while polishing the front surface on the polishing surface using a second fluid delivery arm to deliver a second fluid to the polishing surface at a location that will intersect with the hot spot during polishing of the front surface of the substrate.