Novellus Systems Incorporated

Stmicroelectronics S.r.l.

Senzi Li

David L Chen

Yuh-Jia (Jim) Su

Simone Alba

Simona Petroni

Eddie Ka Ho Chiu

Giuseppe Colangelo

Maria Paola Pozzoli

Helmuth W Treichel

Kirk J Ostrowski

Chevan Goonetilleke

Jim Su

The current invention provides methods for performing a cleaning process that provides greater cleaning efficiency with less damage to device structures. After etching and photoresist stripping, a first plasma clean is performed. The first plasma clean may comprise one or more steps. Following the first plasma clean, a first HO based clean is performed. The first HO based clean may be a de-ionized water rinse, a water vapor clean, or a plasma clean, where the plasma includes hydrogen and oxygen. Following the first HO based clean, a second plasma clean is performed, which may comprise one or more steps. A second HO based clean follows the second plasma clean, and may be a de-ionized water rinse, a water vapor clean, or a plasma clean, where the plasma includes hydrogen and oxygen. For plasma processes, an RF, generated plasma, a microwave generated plasma, an inductively coupled plasma, or combination may be used. Embodiments of the invention are performed after an etch, such as a metal etch, via etch, contact etch, polysilicon etch, nitride etch or shallow trench isolation etch has been performed. Photoresist may be removed either prior to, during, or after cleaning processes according to embodiments of the invention, using an oxygen-containing plasma. Photoresist removal may be performed at low temperatures.

Method for post-etch cleans

The current invention provides methods for performing a cleaning process that provides greater cleaning efficiency with less damage to device structures. After etching and photoresist stripping, a first plasma clean is performed. The first plasma clean may comprise one or more steps. Following the first plasma clean, a first HO based clean is performed. The first HO based clean may be a de-ionized water rinse, a water vapor clean, or a plasma clean, where the plasma includes hydrogen and oxygen. Following the first HO based clean, a second plasma clean is performed, which may comprise one or more steps. A second HO based clean follows the second plasma clean, and may be a de-ionized water rinse, a water vapor clean, or a plasma clean, where the plasma includes hydrogen and oxygen. For plasma processes, an RF generated plasma, a microwave generated plasma, an inductively coupled plasma, or combination may be used. Embodiments of the invention are performed after an etch, such as a metal etch, via etch, contact etch, polysilicon etch, nitride etch or shallow trench isolation etch has been performed. Photoresist may be removed either prior to, during, or after cleaning processes according to embodiments of the invention, using an oxygen-containing plasma. Photoresist removal may be performed at low temperatures.

Methods for post etch cleans

A unique photoresist strip sequence using a downstream plasma system is described. The sequence can include a RF directional plasma alone, downstream plasma alone or combine both RF plasma and downstream plasma together. The process sequence can be a single step or multiple steps, which produce high strip rates while maintaining the dielectric properties of the film. The process can be an oxidizing process carried out at low temperature and low pressure, which reduces the reactivity of the oxygen with the low-k film. Furthermore, by adding a small percentage of an additive gas, such as a fluorine-containing gas, to the plasma, the inorganic residues from the strip process are removed, leaving a clean film cleared of photoresist and residue.

Method for removing photoresist from low-k films in a downstream plasma system

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San Jose, CA, United States of America

Senzi Li