Taiwan Semiconductor Manufacturing Comp. Ltd.

Fang-Wen Tsai

Keng-Chu Lin

Shwang-Ming Jeng

Chih-Lung Lin

Kuan-Chen Wang

Chyi-Tsong Ni

Yu-Min Chang

Wan-Cheng Yang

Jo-Wei Chen

Pong-Hsiung Leu

An extreme low-k (ELK) dielectric film scheme for advanced interconnects includes an upper ELK dielectric layer and a lower ELK dielectric with different refractive indexes. The refractive index of the upper ELK dielectric layer is greater than the refractive index of the lower ELK dielectric layer.

Extreme low-K dielectric film scheme for advanced interconnects

Extreme low-k dielectric film scheme for advanced interconnect

A HDP CVD process for depositing a USG liner followed by a FSG dielectric layer on a metal line pattern is described. The substrate is heated in a chamber with a plasma comprised of Ar and O. A USG liner is deposited in two steps wherein the first step is without an RF bias and the second step is with a moderate RF bias that does not damage the metal lines or an anti-reflective coating on the metal. The moderate RF bias is critical in forming a sputtering component that redeposits USG to form more uniform sidewalls and better coverage at top corners of metal lines. The USG deposition process has a good gap filling capability and significantly reduces device failure rate by preventing corrosion of metal lines during subsequent thermal process cycles. The method also includes a PECVD deposited FSG layer that is planarized to complete an IMD layer.

Solution for FSG induced metal corrosion & metal peeling defects with extra bias liner and smooth RF bias ramp up

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Hsinchu, Taiwan

Fang-Wen Tsai