Fastener Testing

With the WAFERinspect AOI measuring system, Confovis GmbH is expanding its WAFERinspect product range with an AOI tool, which combines defect inspection, defect review, as well as 2D and 3D measurements in a single system. 

For defect detection, the Confovis WAFERinspect AOI uses current computer architecture to compare golden samples in the memory with the current defect scan in ‘real time’. Defect detection reaches a speed of up to 25 FPS because access times to the SSD hard disk as a limiting parameter are eliminated. Compared to currently established standard systems, the Confovis system enables a considerably higher resolution at the same process time, whereby even the smallest defects of a size down to 0.1µ/px are detected on various surfaces and process steps in front end or back end.

Depending on the application, the entire wafer or individual chips can be taught as a ‘golden sample’ for a die-by-die or reticle-by-reticle defect scan. The classification of the defects does not have to be carried out during set-up but can be carried out afterwards and separately based on the defects found.

Defect detection and classification has been implemented together with Confovis’ partner NeuroCheck, a supplier of industrial image processing. A multi-stage process, which is also very robust compared with changes in contrast values, is used. An essential advantage of the NeuroCheck defect detection software is flexible adaptation of the inspection programs to changes in the production process, so that modifications are not necessary. 

Instead, analysis tools can be enhanced as a function block in the program flow, which enables simple iterative adaptation of the test programs to the defects to be found via the GUI. In addition, all changes – including classifier training – can be carried out offline and locally on the user’s premises. This means it is not necessary to transfer sensitive data to a Cloud to extend defect detection.