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Situation

Three-dimensional defects on the sample surface can cause problems during processing or result in breakage. On the bare wafer, saw marks indicate deficiencies in the sawing process and reduce the quality of the wafer. An erroneous firing profile on the rear side of the cell can lead to metal beads that cause breakage when cells are stacked for shipment.

Principle

  • Non-contact measurement on-the fly
  • Special illumination and optical acquisition scheme
  • Visualization and classification of 3D defects

Advantages

  • High-throughput full-area saw mark detection
  • Easy inline integration on belt transport systems
  • Vertical detection limit < 5 micrometer
  • Optimized image analysis
  • Chinese language support
  • Central recipe management and "copy-exact" process
  • Simple and fast calibration option

Technical Data

Topic

Description

Samples to be measured

Monocrystalline wafers
Multicrystalline wafers
Cast-Mono wafers

Processed cell rear sides
 
Square or pseudo square

Wafer size

156 mm

Camera model

1 M Matrix

Resolution

Vertical: 160 µm

Horizontal: 4 µm

Measured features

3D topographic surface map of the wafer, classification for steps and saw marks according to DIN EN 50513

 

Maximum belt speed

400 mm/s

Minimum cycle time

1 s

Machine interface
(horizontal communication)

Serial
Parallel I/o
Parellel I/O combined for Serial for WaferID info)
Datablock via Profibus
Datablock via Ethernet

Data interface
(vertical communication)

XML via TCP/IP
SECS-II/GEM (SEMI PV02)

Note: All technical details are subject to change without prior notice. Only technical specifications contained in quotations and duty books are binding.

User Interface

The GP TOPO-D .Scan reliably detects three-dimensional defects like saw marks, steps and small localized defects like aluminum beads as they occur during firing of rears sides. The GP software evaluates and displays each type of defect, even in Chinese language.