Unity II E 855 SS Dry

Dry etch systems are a class of semiconductor manufacturing equipment used to remove material from a wafer surface through plasma-based or gaseous chemical processes. The Unity II series belongs to Tokyo Electron's family of etch tools designed for production fabs. Etch tools like this one are distinct from wet etch systems, which use liquid chemicals.

Dry etch equipment typically operates by generating a plasma from reactive gases, which then chemically and physically removes material from defined areas of the wafer. The plasma is created in a vacuum chamber where process gases are introduced and energized by an RF power source. The wafer is held on a substrate support, and the etch chemistry, pressure, and power parameters are controlled to achieve the desired pattern transfer.

Etch processes are employed in semiconductor fabrication to define patterns that have been photolithographically imaged in a resist layer. The etch step transfers the resist pattern into underlying layers, such as dielectrics, metals, or polysilicon. Dry etch systems are used in the front-end and back-end portions of wafer processing, depending on the film being etched.

Dry etch systems are applied to pattern a variety of thin film materials, including dielectrics, metals, and semiconductors. The reactive gas chemistry is selected to match the material to be etched, enabling processes such as oxide etch, metal etch, or silicon etch. Dry etch tools are also used for cleaning and descum steps where residual material is removed from a wafer surface.