NSR SF 140 i-Line

Lithography steppers project a patterned image from a photomask onto photoresist on a wafer. Lithography steppers are core patterning tools in semiconductor manufacturing. A stepper exposes one field at a time and repeats that field across the wafer by moving the wafer stage between exposures.

A lithography stepper illuminates a reticle and transfers the reticle pattern through projection optics onto coated wafers. A lithography stepper uses stage motion, optical focus control, and alignment to place repeated exposure fields at defined positions across the wafer. A lithography stepper performs exposure after photoresist coating and prebake, and the latent image is later revealed during development.

Lithography tools sit in the pattern transfer flow between resist preparation and pattern development. Lithography exposure follows wafer priming, photoresist coating, and soft bake. Lithography exposure is followed by post-exposure processing, development, inspection, and then an etch, implant, deposition, or lift-off step depending on the module flow.

Lithography steppers are used to print repeated device and interconnect patterns into photoresist. Lithography steppers support semiconductor patterning wherever a reticle-defined image must be transferred with controlled overlay from layer to layer. Lithography steppers are also used in related microfabrication work that relies on wafer-based optical patterning.