Line-scan image capture is often adopted for the wafer defect inspection. Besides high accuracy, the stage used for wafer positioning also requires good speed stability, otherwise, the captured image may be distorted due to speed variation. This stage is developed for this application.
| ITEM | X axis | Y axis | |
| Stroke | Effective (mm) | 390 | 390 |
| Maximal (mm) | 400 | 400 | |
| Resolution (um) | 0.02 | 0.02 | |
| Straightness (um) | <1 | <1 | |
| Flatness (um) | <3 | <3 | |
| Repeatability (um) | +/- 0.1 | +/- 0.1 | |
| Accuracy (um)
(with laser calibration) |
<0.5 | <0.5 | |
| Maximal speed (m/sec) | 0.4 | 0.4 | |
| Maximal Acc. (G) | 1.5 | 1.5 | |
- Special linear guide arrangement leads to excellent speed stability <0.2mm/s @ 250 mm/s (0.08%)
- Extremely low cogging linear motor is used to minimize speed ripple.
- Black anodizing surface treatment to reduce reflection light interference.