MICRO-EPSILON Messtechnik GmbH & Co. KG

Manufacturer
Germany
Company contact

Manufacturer
Germany
Company contact

08.03.2024 01:03

Thickness and structure measurement of solar wafers

In the production of solar wafers, the raw wafers are first sawn from the so-called ingots. These must maintain a specified thickness of around 180 µm before they can be processed further as a good part.

Six capacitive sensors therefore measure the blanks on a conveyor belt. Two sensors are always arranged opposite each other so that a total of three thickness tracks can be evaluated. A multi-channel controller with integrated calculation directly determines the precise thickness signal, which is used to evaluate the parts as OK/NOK. In addition, the respective distance signal is also output and evaluated with regard to surface quality or possible unevenness.

The solution with capacitive sensors has the advantage of precise and stable thickness measurements. Compared to optical systems, capacitive sensors are much more accurate. the capaNCDT 6200 multi-channel system with integrated calculation option can also be used to output both the distance and the thickness signal.