| 摘要 |
<p>PURPOSE:To obtain the device having high accuracy by setting each element so that only a luminous flux in which history of the degree of diffraction received by a first and a second alignment marks is general is condensed on the prescribed surface, at the time of executing relative positioning of a first and a second objects. CONSTITUTION:At the time of aligning the surface of an object 1 and the surface of an object 2, alignment marks 5, 6 for a first and a second signals are formed on the surface of the object 1, and also, alignment marks 3, 4 are formed on the surface of the object 2, as well. In such a state, a luminous flux is made incident on the mark 5, a diffracted light generated in that case is made incident on the mark 3, and the centroid of the luminous flux on the incident surface of the diffracted light from the mark 3 is detected by a first detecting part as an incident position of a first signal luminous flux. In the same way, it is detected by a second detecting part as an incident position of a second signal luminous flux through the marks 6, 4. In this case, each element is set so that (m', n', l')-order light which becomes a detection error factor against (m, n, l)-order light is not made incident on the detection surface. In such a way, the accuracy can be stabilized and high accuracy can be obtained.</p> |
