Wafer-Level Kerr Effect Measurement Instrument

The Wafer-Level Kerr Effect Measurement Instrument delivers powerful vertical and in-plane magnetic field capabilities for advanced wafer-level magnetic characterization.

• Magnetic fields: up to 2.5 T vertical and 1.3 T in-plane, enabling precise flipping of the free, reference, and pinned layers in vertical anisotropic MRAM film stacks.
• Ultra-high Kerr detection sensitivity: capable of simultaneously characterizing subtle magnetic changes in multiple film layers.
• By combining laser point-by-point detection with scanning imaging, the system rapidly generates global wafer magnetic property maps, assisting in process optimization and yield control.

Measurement results of hysteresis loops of perpendicular anisotropic magnetic tunnel conjunctival stack

Coercive field characteristic distribution diagram of 8-inch perpendicular magnetic anisotropy wafer

• Supports wafer sizes up to 12 inches, with full backward compatibility and fragment testing.
• High field capability: maximum vertical field ±2.5 T, with 1 μT resolution.
• Kerr rotation detection sensitivity better than 0.3 mdeg (RMS), ideal for multilayer film stack characterization.
• Precise sample positioning: repeat accuracy better than ±1 μm; static jitter ≤ ±0.25 μm.
• Flexible scanning modes: single point, array, ring distribution, or custom position lists.
• Options for manual loading or fully automated operation for both R&D and production environments.

• Vertical anisotropic MRAM stacks and device arrays
• Perpendicular magnetic recording (PMR) disk media
• Multilayer film stacks for magnetic sensors
• Fragment or full-wafer magnetic testing

Applications include:

• Wafer-level hysteresis loop measurement
• Process optimization and quality control
• Layer-specific magnetic parameter extraction (Hc, Hex, Ms)

• Wafer-level stage with precision alignment
• High-field electromagnet (vertical and in-plane)
• Ultra-sensitive Kerr detection module
• Integrated laser scanning and imaging system
• Automated positioning and motion control unit

• Real-time data acquisition and processing
• Automatic hysteresis loop extraction for free and pinned layers
• Mapping and visualization of wafer-level magnetic properties
• Preset and customizable scanning patterns (single point, array, ring)
• Export functions for integration with R&D and production databases

Model: Wafer-Level Kerr Effect Measurement Instrument
Standard Components: Wafer stage, electromagnet, Kerr optics, laser scanning module, software suite