| 摘要 |
PURPOSE:To increase the number of alignment masks to be contained in a scribing region by a method wherein an alignment mark is formed so as to be piled up in the same position as an alignment mark used in a mask process before a formation operation of an insulating film. CONSTITUTION:Simultaneously with an operation to form a pattern in a first mask process, an alignment mark 4a is formed; simultaneously with an operation to form a second pattern, an alignment mark 4b is formed. After the second pattern has been formed, a flattening layer 7 and an insulating layer 5 are formed. When a third pattern formation layer on the insulating layer 5 is formed of an opaque material such as aluminum or the like, an alignment mark 4c is formed on the insulating layer 5 by using the mark 4b as a reference before an opaque layer 6 is formed. The two marks 4a and 4c are detected simultaneously before the opaque layer 6 is formed; however, after the opaque layer 6 has been formed, the mark 4a becomes invisible; this situation does not constitute an obstacle when a mask is aligned with the mark 4c. Even when the flattening layer 7 is not formed, a profile of an uneven part of the mark 4c appearing on the surface of the opaque layer 6 is clear as compared with an uneven part caused by the mark 4a under it; this situation does not constitute an obstacle when the mask is aligned with the mark 4c. |
