2300 Exelan

Etch systems remove selected material from wafer surfaces by using a dry plasma process instead of a liquid chemical bath. Dielectric etch tools are used to pattern insulating films after a masking step has defined where material should remain and where material should be removed. Dielectric etch equipment belongs to the plasma etch segment of wafer fabrication tools.

Plasma etchers operate by placing a wafer in a vacuum process chamber and introducing reactive gases. Radio frequency power sustains a plasma that generates ions and neutral species that react with exposed film areas. Plasma etchers balance chemical reaction and ion-assisted removal so that the patterned mask can be transferred into the underlying layer with controlled profile and selectivity.

Dielectric etch tools are used after a patterned masking step has exposed selected areas of an insulating film. Dielectric etch tools transfer that pattern into the underlying dielectric layer before later stripping, cleaning, barrier, fill, or deposition operations continue device fabrication. Dielectric etch equipment therefore sits between pattern definition and subsequent integration steps in wafer processing.

Dielectric etch tools are commonly used to open vias, trenches, contact features, and other patterned features in insulating films. Dielectric etch processes are applied where later integration steps require precisely defined openings through oxide or other nonconductive layers. Dielectric etch tools are also used where profile control and selectivity are important to pattern transfer.