Forming a back-illuminated type CMOS image sensor, includes process for
formation of a registration mark on the wiring side of a silicon
substrate during formation of an active region or a gate electrode. A
silicide film using an active region may also be used for the
registration mark. Thereafter, the registration mark is read from the
back side by use of red light or near infrared rays, and registration of
the stepper is accomplished. It is also possible to form a registration
mark in a silicon oxide film on the back side (illuminated side) in
registry with the registration mark on the wiring side, and to achieve
the desired registration by use of the registration mark thus formed.