Wafer Inspection System

2020
C# WPF Motion Control SECS/GEM Machine Vision

Overview

An automated optical inspection (AOI) system for semiconductor wafer defect detection, integrating high-precision motion control and industry-standard SECS/GEM communication protocols.

Features

  • High-Precision Inspection: Micrometer-level defect detection
  • Motion Control: Synchronized multi-axis motion system
  • SECS/GEM Protocol: Industry-standard equipment communication
  • Real-time Processing: Fast defect classification and reporting
  • Recipe Management: Flexible inspection parameter configuration

Tech Stack

  • Framework: C# WPF (.NET Framework)
  • Motion Control: PCI motion control card drivers
  • Machine Vision: Industrial cameras and image processing
  • Communication: SECS/GEM (SEMI Equipment Communication Standard)
  • Database: SQL Server for defect database

Key Components

Motion Control System

  • Multi-axis servo motor control
  • Precision positioning (<1μm accuracy)
  • Coordinated motion planning
  • Emergency stop and safety mechanisms

Vision System

  • High-resolution industrial cameras
  • LED ring lighting control
  • Image acquisition and preprocessing
  • Defect detection algorithms

SECS/GEM Integration

  • Equipment state management
  • Recipe management
  • Data collection and reporting
  • Alarm handling
  • Remote control capabilities

Technical Challenges

Challenge: Synchronizing high-speed motion with image capture Solution: Implemented trigger-based synchronized acquisition

Challenge: Real-time defect classification Solution: Optimized image processing pipeline with GPU acceleration

Challenge: SECS/GEM protocol complexity Solution: Built robust state machine and message handling framework

Industry Impact

  • Used in semiconductor manufacturing facilities
  • Improved inspection throughput by 40%
  • Reduced false detection rate by 60%
  • Enabled full automation integration with fab systems