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TEX-Q
Inline optical inspection system for control of texture quality, surface reflection and contamination
overview

Situation

Wafer surface texturing is one of the most important processes for increasing electrical output of a solar cell. Texturing with wet chemical processes is now standard practice. Yet, these chemical processes cause visible impurities like dark stains and lines. TEX-Q precisely detects all contamination and defects on the textured wafer surface. It also checks the texture quality and surface reflection. Wafers with defects or other deviations from classification threshold values are reliably rejected.

Principle

  • Optical inspection system
  • On-the-fly measurement

Advantages

  • Throughput of up to 3600 wafers/hour, with 100% control rate
  • Shows long-term process drift
  • Central recipe management and “copy-exact” process
  • Simple and fast calibration option
  • Constant calibration control
  • Defect Overlay to easily identify systematic and reoccuring defects
  • Chinese language support

Technical Data

Topic

Description

Samples to be measured

Multicrystalline and cast-mono wafers
Square or pseudo square
Alkaline or acid texture

Wafer Size

156mm

Camera model

2K / Linescan

Defect resolution

80µm

Measured features

Surface reflectance, reflectance variance, separate treatment of reflectance  at wafer edges, etch pits

Maximum belt speed

400 mm/s

Minimum cycle time

1s

Machine interface
(vertical communication)

Serial
Parallel I/O
Parallel I/O (combined with RS232 for Wafer ID info)
Profibus Datablock oriented
UDP Datablock oriented

Data interface
(horizontal 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 an offer are binding.