Barrier and Etch Stop Film

The company offers its BLOk (Barrier Low k) dielectric CVD (chemical vapor deposition) film. It provides an alternative to silicon nitride films, enabling chipmakers to reduce the dielectric constant (k) of their overall copper damascene structures to achieve faster, more powerful devices.

Silicon nitride (SiN) films are currently used as a copper barrier and etch stop in combination with low k dielectrics to form insulating film "stacks" between the chip's copper circuitry.

Although silicon carbide-based films traditionally exhibit poor electrical integrity and have been difficult to etch, BLOk, which is s proprietary amorphous film composed of silicon, carbon and hydrogen, actually exceeds the performance of nitride as a diffusion barrier and demonstrates leakage that is six to seven orders of magnitude better than conventional silicon carbide material.

The company has already characterized BLOk on its Dielectric Etch IPS Centura system to provide an integrated process that first etches through the primary intermetal dielectric, Black Diamond, and then stops on the BLOk layer before proceeding with a soft etch to break through the BLOk and stop on the copper. This two-step process prevents sputtering of the copper onto the dielectric sidewalls and eliminates copper contamination to the device.

The process uses the company's DxZ CVD chamber, enabling chipmakers to rapidly integrate the process into their production lines using proven, well-known hardware. The process can also be retrofitted on existing DxZ chambers for copper pilot lines.

Applied Materials, 3050 Bowers Ave., Santa Clara, CA 95054. Tel: 408-727-5555. Fax: 408-986-8352.