Technology is key for the AMTC in order to be a world-leading mask center for R&D as well as a pilot production site of optical photomasks for the advanced lithographic generations (193 nm, 193 nm with immersion, and EUV) . One of the major R&D fields at the AMTC is Resolution Enhancement Technologies (RET), which allow customers to print features on the wafers that by now are considerably smaller than the illumination wavelength.
Photomasks are high-purity quartz or glass plates with precision images of integrated circuits designs (semiconductor chips). Photomasks are used as masters to optically transfer these images onto silicon wafers.
Current advanced lithographic tools such as deep-UV (DUV) steppers and scanners project light through the photomask and a high-aperture lens. The intensity profile of the light generates an image of the design onto the wafer coated with a light-sensitive material called the photoresist. Using negative photoresist, the unexposed portion of this material is then removed, so the wafer can then be etched to form channels or other materials can be deposited.
Semiconductor chips are manufactured layer by layer, hence the described deposition or removal steps are repeated until the final circuit is completed. The current generation of semiconductor chips commonly have 25-60 layers. Each layer requires a unique photomask.
The following methods are used for the production process: