This exposure system accommodates wafers ranging from 20mm up to Φ8 inches and is equipped with the same optical system for magnification projection exposure with a minimum specification of 5µmL/S. For the purposes of MEMS, the system is equipped with Ushio's unique projection lenses with long depth of field (up to ±50µm). The system is most suitable for exposing stepped substrates, concavo-convex substrates and thick photoresist films.
In addition, reverse-side alignment (optional) makes it possible to expose the reverse side as well.
The unit features projection lenses with long depth of field (up to ±50µm).
The unit uses the through-the-lens method. Alignment is performed while each mask and workpiece indication is viewed directly through a microscope, enabling highly accurate alignment.
There is no contact between the mask and workpiece, thereby eliminating the risk of damage to the mask. The mask can therefore be used on a semi-permanent basis.
A mask with pellicles can be attached, allowing exposure to be performed without considering debris on the mask pattern area. In addition, the design minimizes debris on the mask because the focus is on the mask pattern area.
As the unit has no exposure drive, it is only necessary to conduct verification once a year. Operation using the recipe system ensures perfect repeatability.