Case Study: Submicron Inspection with custom PAX-it! software

Executive Summary

In semiconductor R & D, repeatable measurements at submicron scale separate signal from noise. A major US National Laboratory partnered with MIS to build a custom wafer inspection workflow that standardizes capture, motion control, and measurement using PAX-it software with a PAXcamX5 camera and integrated control of Olympus motorized microscopes and Prior Scientific stage. The solution delivers high-throughput scanning, precise site mapping on 10-inch wafers, and repeatable revisits under identical imaging conditions. Images, measurements, and context are archived together, creating a single system of record for Critical Dimension analysis and wafer documentation.

About the Customer

• Industry: National Laboratory, semiconductor research and quality control
• Region: United States
• Team: Multidisciplinary scientists and engineers conducting high-volume wafer fabrication experiments
• Focus: Experimental wafer characterization with repeatable Critical Dimension workflows

The Challenge

The lab needed to document large 10-inch wafers and perform Critical Dimension measurements across many fields of view while maintaining speed, positional accuracy, and reproducibility. Core requirements included:

• High-throughput scanning with the ability to return to precise wafer locations for before and after comparisons
• Multiple optical techniques and magnifications to match field sizes and features of interest
• Exact restoration of imaging conditions for re-captures, including focus position and illumination
• Centralized archival of high-resolution images and associated measurements for search, review, and method traceability
• No single off-the-shelf workstation met these constraints. Fragmented tools risked variability, rework, and lost context between imaging and measurement sessions.

The Solution

MIS delivered a custom PAX-it solution that combines off-the-shelf capability with targeted programming and integrated device control.

Hardware integration

• Microscope and optics: Olympus USA motorized microscope platform supporting multiple optical techniques and magnifications
• Motion system: Prior Scientific motorized stage with calibrated X, Y, Z, and theta control
• Imaging: PAXcamX5 digital microscope camera for high-resolution capture

Software and control

• Device SDK integration: MIS used vendor SDKs to drive microscope and stage motion from within the PAX-it environment
• Calibrated motion and measurement: Custom code in PAX-it established precise calibration for X, Y, Z, and theta so stored points could be revisited with submicron accuracy
• Reproducible conditions: After navigating to the appropriate X, Y, Z and adjusting Theta, the scripts reset the microscope to the exact optical technique, focus position, and illumination used during the original capture
• User-defined targets: Operators define new target points for documentation and Critical Dimension measurement without leaving the workflow
• Searchable archival: Images and measurements are saved to a structured, searchable PAX-it database to preserve context

Implementation and adoption

• Role-based training aligned operators on capture discipline, step-through routines, and CD measurement procedures
• SOPs codified site storage, revisit methods, and condition resets to ensure consistent outcomes across users and runs
• Configuration guidance and light customizations supported rapid deployment and future extensibility

The Results

• Submicron revisitability: Stored wafer points can be re-located with submicron precision for confident comparisons over time
• Repeatable CD measurements: Standardized measurement steps and restored imaging conditions improve consistency across operators
• Throughput at scale: Motorized step-through of fields of view reduces manual handling and accelerates documentation cycles
• Single system of record: High-resolution images, measurement outputs, and site maps are archived together for traceability and review
• Extensible foundation: The approach supports additional scripts and routines as methods evolve

Compliance and Quality Notes

• Calibrated motion control across X, Y, Z, and theta supports consistent positioning between sessions
• Restored optical technique, focus, and illumination enable like-for-like comparisons
• Centralized image archival and measurement logs maintain method traceability for internal reviews and external collaboration
• SOP-aligned workflows reinforce repeatability and audit readiness

Closing

When wafer characterization depends on submicron precision and repeatable revisits, PAX-it custom programming with PAXcam and integrated device control provides a reliable path from requirement to routine. If your workflow demands more than off-the-shelf capabilities, contact MIS to scope a custom PAX-it solution for semiconductor R & D and QC.