| 摘要 |
<p>PURPOSE:To raise the accuracy of detection, by irradiating light upon a semiconductor chip whose position is to be detected and by picking up an image of pads on the chip, detecting a pad disposition pattern from picture element signals obtained as a result of the image picking-up, sampling the pattern and using the sampled pattern to detect the position. CONSTITUTION:A half mirror 18 is installed over a semiconductor chip 10, the pad position of which is to be detected. Light is irradiated upon the half mirror from an image pickup unit light source provided beside the mirror. The chip is irradiated with the light reflected by the mirror. An image pickup unit 24 attached to a moving stage 26 is installed over the mirror 18. Picture element signals obtained by the image pickup unit are applied to a threshold value calculation circuit 34 through an A/D converter 30 and stored in a memory 36. The unit 24 is then displaced by a driving circuit 28 through a comparator 36, a pattern detector 38 and a pad position detector 40 to scan a pad image. At the same time, information stored in the memory 32 is computed by the calculation circuit 34. The cmputed information is indicated prescribed display unit.</p> |
