Nikon's Optiphot-88 integrated circuit inspection microscope entered into the marketplace around 1987, supplanting the Optiphot-66 and its 6-inch by 6-inch stage. Among the many primary improvements in the instrument's design was an increase in stage size that enabled the inspection of 8-inch silicon wafers.
Those manufacturers that already possessed the Optiphot-66 were not forced to abandon the wafer and mask holders they utilized with the older instrument, but were able to use them in conjunction with the Optiphot-88 through the aid of an adapter. In fact, a six-inch stage could also be attached to the instrument with an adapter. The enhanced Optiphot-88 stage, however, was easier and faster to operate than that of its predecessor due to the inclusion of an electronic clutch system. A workhorse in the silicon chip industry for many years, the Optiphot-88 was eventually overshadowed by more recent models as new manufacturing, inspection, research, and development demands led to technological innovations. In particular, newer integrated circuit inspection models incorporate Nikon's infinity-corrected CFI60 optical system.
Accommodating to various optional attachments, the Optiphot-88 instrument illustrated above is shown with the Nikon universal epi-illuminator and the Nikon model HFX-II automatic Microflex photomicrographic system. Fully automatic, the photomicrographic system features a Microflex FX series main body with a 4x focusing magnifier, a 35-millimeter camera adapter, and internal silicon photodiode light metering. The Nikon HFX-II camera back appears with the optional motorized film advance installed. During a photographic exposure, prisms and other reflective surfaces are removed from the optical path and the direct projection system supplies all of the light to the film.