Wafer Bevel Polishing with Automatic Shape Recognition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polishing apparatuses face challenges in efficiently polishing semiconductor wafers with varying bevel shapes, leading to increased downtime and defective polishing due to the need for manual adjustment of polishing conditions.
Innovation Solution
A polishing apparatus equipped with an identifying unit that determines the cross-sectional shape of the wafer before polishing, selecting a suitable polishing condition from pre-determined types based on data obtained, and a controller that adjusts the polishing process accordingly, using techniques such as confocal laser microscopy or template matching to ensure optimal polishing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If operators manually adjust polishing conditions for each wafer bevel shape, then polishing quality can be maintained, but processing time increases and productivity decreases
Solution Approach 1:
The system performs preliminary classification of wafer bevel shapes using an identifying unit before polishing. The polishing condition determining unit pre-establishes multiple polishing recipes corresponding to different bevel shape types. By identifying the wafer type in advance and selecting the appropriate pre-determined polishing condition, the system eliminates manual adjustment time while ensuring optimal polishing quality for each wafer type.
Solution Approach 2:
The system changes polishing parameters (such as pressing force, rotation speed, polishing tape feed rate) based on the identified bevel shape type. The polishing condition determining unit selects from multiple predetermined polishing conditions that have different parameter settings optimized for different wafer types, allowing automatic adaptation to various bevel shapes without manual intervention.
2Manufacturing precision
If operators set up polishing conditions from experience for each wafer type, then appropriate polishing can be achieved, but device complexity and operational difficulty increase
Solution Approach 1:
The polishing apparatus performs self-service by automatically identifying wafer bevel shapes and selecting appropriate polishing conditions without operator intervention. The identifying unit automatically captures wafer images, the polishing condition determining unit automatically selects the matching polishing recipe based on identified characteristics, and the control unit automatically applies the selected conditions, making the system self-sufficient and eliminating the need for operator expertise in manual setup.
Solution Approach 2:
The system replaces the manual mechanical adjustment process with an automated optical-mechanical system. Instead of operators visually inspecting and manually adjusting polishing parameters, the system uses an identifying unit with optical components to capture wafer images, processes the images to determine bevel shape characteristics, and automatically selects polishing conditions, substituting human judgment and manual operation with automated detection and control.
3Stability of the object's composition
If multiple wafer manufacturers are sourced to ensure stable supply, then supply stability improves, but variability in bevel shapes increases polishing difficulty
Solution Approach 1:
The polishing apparatus achieves universality by being capable of processing wafers from multiple manufacturers with different bevel shape specifications. The identifying unit is designed to recognize various bevel shape types regardless of manufacturer, and the polishing condition determining unit maintains a library of multiple polishing recipes that can be selected based on the identified wafer type, allowing the single apparatus to universally handle diverse wafer sources.
Solution Approach 2:
The system segments wafer bevel shapes into distinct types or categories based on their geometric characteristics. By classifying wafers into discrete groups (such as different bevel angle ranges or shape profiles), the system can match each segment with a specific polishing recipe, making it easier to manage the variability introduced by multiple manufacturers through systematic categorization.
Data Source
Figure 1(a)~1(b)
Figure 2
Figure 3(a)~3(b)
AI summary
To provide a polishing apparatus capable of polishing bevel portions of varying shape by selecting a suitable polishing recipe, based on a state before polishing. The polishing apparatus 100 comprises: a holding/polishing unit 102 for holding and polishing a workpiece W1; and an identifying unit 104 for identifying data 104a associated with a state of the peripheral portion of the substrate W1 before polishing. The holding/polishing unit 102 comprises: a holder 106 for holding and rotating the substrate W1; and a polisher 108 for polishing the peripheral portion of the substrate W1 by pressing a polishing member against the peripheral portion. A polishing-condition determiner 110 determines a polishing condition, based on data 104a indicating to which type, of a plurality of shape-related types, the shape of a given peripheral portion belongs.