Taiwan Semiconductor Manufacturing Comp. Ltd.

Hong-Ta Kuo

I-Shi Wang

Sheng-Yuan Lin

Yuan-Hsin Chi

Hsing-Yu Wang

Tzu-Ping Yang

Hsi-Cheng Hsu

Yin-Tun Chou

Shu-Han Chao

Yen Hao Huang

Huang-Liang Lin

Ming-Yi Shen

Yin-Tung Chou

A preclean process may be omitted from a eutectic bonding sequence. To remove oxide from one or more surfaces of a device wafer of a micro-electromechanical-system (MEMS) structure, a duration of an acid-based etch process in the eutectic bonding sequence may be increased relative to the duration of the acid-based etch process when the preclean process is performed. The increased duration of the acid-based etch process enables the acid-based etch process to remove the oxide from the one or more surfaces of the device wafer without the use of a preceding preclean process. This reduces the complexity and cycle time of the eutectic bonding sequence, reduces the risk of stiction between suspended mechanical components of the MEMS structure, and/or reduces the likelihood that the MEMS structure may be rendered defective or inoperable during manufacturing, which increases process yield.

Extended acid etch for oxide removal

Methods and systems for improving fusion bonding are disclosed. Plasma treatment is performed on a substrate prior to the fusion bonding, which leaves residual charge on the substrate to be fusion bonded. The residual charge is usually dissipated through an electrically conductive silicone cushion on a loading pin. In the methods, the amount of residual voltage on a test silicon wafer is measured. If the residual voltage is too high, this indicates the usable lifetime of the silicone cushion has passed, and the electrically conductive silicone cushion is replaced. This ensures the continued dissipation of residual charge during use in production, improving the quality of fusion bonds between substrates.

Methods and systems for improving fusion bonding

Growing community of inventors

Hsinchu County, Taiwan

Hong-Ta Kuo