Multi-Modal Fiducial Structure for Semiconductor Image Alignment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing semiconductor manufacturing processes face challenges in accurately detecting and characterizing crystalline defects and features on semiconductor workpieces due to alignment issues when stitching multiple images from different image modalities, leading to inaccurate composite images.

Innovation Solution

A semiconductor workpiece inspection system utilizing a fiducial structure with fiducial markers detectable in multiple image modalities, enabling spatial correlation and alignment of images to generate accurate composite image data.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple images from different image modalities are used to inspect semiconductor workpieces, then the comprehensiveness of defect detection is improved, but alignment accuracy between images deteriorates due to stitching misalignments

Engineering Contradiction:

Improvecomprehensiveness of defect detectionVSAvoidalignment accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent introduces fiducial markers as intermediary reference objects that are detectable across multiple image modalities. These markers serve as common reference points between different imaging systems (e.g., optical microscopy, scanning electron microscopy), enabling accurate spatial correlation and alignment despite the different physical principles used in each modality. The fiducial markers act as a mediator that translates between different imaging coordinate systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The fiducial markers are designed to be detectable in multiple image modalities simultaneously, giving them universal applicability across different inspection systems. This multi-functionality allows a single reference structure to work with various imaging techniques (optical, electron, etc.), enabling comprehensive defect detection while maintaining consistent alignment references across all modalities.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Measurement precision

If multiple imaging modalities are combined to characterize crystalline features, then the accuracy of feature characterization is improved, but the complexity of image processing increases

Engineering Contradiction:

Improveaccuracy of feature characterizationVSAvoidcomplexity of image processing

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent performs preliminary alignment using fiducial markers before the actual defect analysis. By establishing the spatial relationship between different image modalities in advance through the common reference points, the complex task of multi-modality image registration is simplified. This preliminary alignment step reduces the computational complexity required for subsequent defect characterization.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If fiducial markers are added to the semiconductor workpiece, then the reliability of spatial correlation is improved, but the manufacturing complexity increases

Engineering Contradiction:

Improvereliability of spatial correlationVSAvoidmanufacturing complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The fiducial structure is segmented into discrete, identifiable markers that can be independently formed on the semiconductor workpiece. This segmentation allows the fiducial markers to be created as separate features rather than requiring complex modifications to the entire workpiece structure, thereby reducing manufacturing complexity while maintaining reliable spatial correlation references.

Inventive Principle:

Principle #1Segmentation

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

Improves the accuracy of defect assessments and quality control by reducing stitching misalignments and motion errors, enhancing imaging system performance while decreasing costs.

Implementation Method 1

The first region has different optical characteristics relative to the second region

Methodology Applied

Scientific EffectOptical characteristics: Absorption (EM radiation)

Data Source

PatentUS20260002886A1Fiducial Structure for Inspection of Semiconductor Workpieces

Publication Date: 2026.01.01 WOLFSPEED INC

AI summary

An example semiconductor workpiece imaging system includes an imaging device. The example semiconductor workpiece imaging system includes a workpiece holder operable to receive a semiconductor workpiece. The example semiconductor workpiece imaging system includes a fiducial structure having one or more fiducial markers. The one or more fiducial markers and at least a portion of the semiconductor workpiece are detectable in a plurality of different image modalities.