Film Metrology in Wafer Inspection
Granite-Based Motion Systems for Cost-Effective Scanning and Location of Defects
For every type of wafer, key prerequisites include uniform substrate and device layer thickness, along with a minimal defect density. Moreover, the wafer‘s electrical resistivity must closely align with specified standards. Certain films necessitate characterization, especially for assessing thickness, electrical resistivity, and surface quality and roughness. Reliable and fast measurement technologies help to prevent yield losses by detecting defects in an early stage, and thereby reducing costs.
PI is currently developing motion solutions for wafer positioning to facilitate the measurement of crucial wafer attributes.
θ Axis - Fine Rotary Indexing and Alignment of Wafer or Substrate
- Highly accurate and repeatable 360° rotation without backlash
- High velocities and accelerations due to magnetic direct drives
- Direct-drive, slotless, brushless torque motor offers very low cogging torques and enables smooth speed and low error motions
- Ultra-precise air bearings developed and manufactured in house
- Next level performance to further optimize asynchronous performance specifications
>> Technology of Direct Drive Torque Motors
Z Axis - Precision Wafer Alignment
- Low profile, high load, compact superior design
- Direct drive voice coil technology provides zero cogging, smooth motion with nanometer step size and response
- High-resolution encoder for nanometer positioning of the motion platform
- High-precision anti-creep crossed-roller bearings
- Pneumatic counter balance prevents motor heating and avoids collisions
- Economically priced with fast delivery
>> Technology of Direct Drive Motors
XY Axis – Precision Step and Scan Motion
- High-dynamics, coupled ironless linear motors on base axes for powerful, fast and precise motion
- Dual encoder system ensures motor and yaw alignment, while providing high resolution and accuracy
- Multiple bearing stiff platform with low profile reduces abbe offsets and offers increased flatness and straightness
- Design allows high flexibility and customization
- Optimized integrated cable management reduces motion drag and prolongs lifetime
- Granite base ensures highest performance of the motion system
- Optional active isolation
>> Direct Drive Linear Motor Stages
Flexible and Easy Automation Control
- EtherCAT® controller for open network connectivity
- Advanced algorithms provide fast step-and-settle, high in-position stability, and exceptional constant scanning velocity
>> ServoBoost™ - Autofocus capabilities of the controller for dynamic focus adjustment
- Look-ahead capability adjusts velocity to maintain accuracy
>> Motion Controllers
