By Cameron Chai
San Jose-based Novellus Systems has added the VECTOR Excel to its VECTOR line. It is a modular system that targets advanced nodes needing dielectric film processing, like diffusion issues. It has an interface fabricating approach that reduces the RC delay. It does not need new materials to be added to the back-end-of line (BEOL) integration.
When the inter-metal dielectric (IMD) substances display a dielectric constant of 2.6 or more, an in-situ plasma treatment with ammonia or hydrogen is used to help dielectric diffusion barrier deposition by eliminating the copper oxide layer and the chemical mechanical planarization (CMP) residue from the slurry.
Novellus' VECTOR Excel
The porous, ultra-low k (ULK) substances at the 28nm node make the films vulnerable to carbon loss when exposed to the in-situ plasma. An increase in the dielectric constant also occurs. To address these issues, the company has developed a remote plasma pre-treatment module (CLEAR) and a dual pre-heat and pre-treatment spectral irradiance module (LUMIER)
This platform can be used with a variety of lamps of varying frequencies. Information gathered also shows that the pre-treatment choices help to remove the copper oxide and CMP residue. The adhesion strength of the diffusion barrier to layers beneath matches results from tests using a normal in-situ plasma treatment. The VECTOR Excel integrated process reduces capacitance. The zero damage process helps interconnect RC delay reduction without needing additions to the BEOL dielectric stack.
The PECVD module employs a multi-station sequential deposition (MSSD) for wafer-to-wafer, within-wafer and point-to-point reuse. The platform has a small footprint compatible to the VECTOR Express.