| 摘要 |
<p>PURPOSE:To reduce the cost by moving a stage which places a wafer, moving an image sensor for sensing the wafer, and detecting a repetition pattern on the wafer. CONSTITUTION:A controller 13 is operated by a command from a computer, sensors 5, 6 detect the profile position of an IC chip to move a stage 12 so that an IC ship 19 is seen in a visual field 12 of a sensor 11 by position signals 5a, 6a. The sensor detects a street 20 by the signal waveforms of the sensors 5, 6, and applies the value to a circuit 18. The field 21 of the sensor 11 is moved by driving a motor 8 by a command from the controller 13 to move the stage 10. A signal 11a is applied to a circuit 15 synchronously with the output pulse of an encoder 9 to indicate the position of the sensor 11. The circuit 15 digitally converts a video analog signal, writes the signal in a memory 16 to inspect regions lxXly from the position x0, y0 on the basis of the data applied to the circuit 18. Thus, since a wafer stage merely conveys an element to be inspected to an optical system position in rough accuracy, it can be extremely inexpensively composed.</p> |
