Embedded Wafer Inspection Using Transmitted Light Patterns
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer processing methods fail to reliably detect damages, which can lead to functional deficiencies in semiconductor devices and damage processing tools, reducing throughput rates in production plants.
Innovation Solution
Implement a fully automatic wafer damage inspection method by emitting a reference light pattern that traverses the wafer, comparing it with received light patterns, and using image processing to determine quality parameters indicative of material characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If manual inspection methods are used to detect wafer damages, then detection reliability may be improved, but productivity decreases and time loss increases
Solution Approach 1:
The patent replaces manual mechanical inspection with an automated optical inspection system that uses light sources and cameras to detect wafer damages. This substitution enables automatic detection without human intervention, simultaneously achieving high reliability through consistent automated measurement and maintaining productivity by eliminating manual handling time
Solution Approach 2:
The inspection system is integrated directly into the wafer processing chain, enabling the system to automatically inspect wafers during or between processing steps without requiring separate manual inspection steps. The system self-regulates by controlling the inspection process, image capture, and damage detection autonomously
2Measurement precision
If separate analysis steps are inserted into the processing chain to inspect wafers, then detection precision improves, but throughput rate decreases
Solution Approach 1:
The patent merges the inspection function with the existing wafer processing chain by integrating the optical inspection system into the processing equipment itself. This allows inspection to occur during or between processing steps without requiring separate dedicated inspection stations, thereby maintaining throughput while achieving precise detection through the integrated optical system
Solution Approach 2:
The inspection process is designed to occur continuously within the processing flow rather than as discrete interruptive steps. The optical system captures images during wafer transport or between processing operations, ensuring that the useful action of inspection continues without breaking the overall processing continuity, thus maintaining throughput rate while achieving precise detection
3Productivity
If real-time inspection is implemented during processing, then productivity is maintained, but device complexity increases
Solution Approach 1:
The inspection system is designed as a multi-functional module that can be integrated into various types of wafer processing equipment. By creating a universal inspection solution that serves multiple processing contexts, the patent avoids the need for separate complex inspection systems for each processing step, thereby maintaining productivity through real-time inspection while managing device complexity through standardization
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
Enables real-time detection of wafer damages without disrupting the processing chain, ensuring only undamaged wafers are further processed, maintaining throughput rates and preventing tool damage.
Implementation Method 1
subjecting the wafer to a light emitted by a light source, wherein the light source emits the light with a reference light pattern; and the emitted light penetrates the moving wafer
Implementation Method 2
generating, by the camera device and based on the light that was emitted by the light source and penetrated the moving wafer, receipt image data indicative for a receipt light pattern
Data Source
Figure 1~2
Figure 3~4
Figure 5~6(B)
AI summary
A system (300) for processing a wafer (100) includes an apparatus for automatically analyzing the wafer (100), wherein the apparatus comprises: a camera device (310), a light source (320), a processing unit (340), and means (330) for effecting a relative movement between the wafer (100) and the camera device (310) and so as to subject, during the relative movement between the wafer (100) and the camera device (310), the wafer (100) to a light emitted by the light source (320), wherein the light source (320) emits the light with a reference light pattern, and wherein the emitted light penetrates the moving wafer (100). The camera device (310) is configured to generate, based on the light that was emitted by the light source (320) and penetrated the moving wafer (100), receipt image data indicative for a receipt light pattern. The processing unit (340) is configured to determine a difference between the reference light pattern and the receipt light pattern based on the receipt image data and reference image data. The processing unit (340) is configured to determine, based on the difference, a quality parameter indicative for a material character of the wafer (100).