Tokyo Electron Ltd. (TEL) and Novellus
Systems, Inc. (NASDAQ: NVLS) are pleased to announce the availability of
an integrated copper interconnect solution for the 2Xnm generation and beyond.
This integrated metallization scheme is the result of a joint program established
between the two companies for the continuous advancement of copper interconnect
The co-developed process employs an ionized PVD TaN or Ti barrier capped with
an ultra-thin CVD Ruthenium (Ru) liner. This barrier and Ru liner is then coupled
with a proprietary copper wet seed process (eliminating the PVD Cu seed process)
and a copper electrochemical deposition process, which yields fully-filled fine
features at the 2Xnm node without the issues associated with PVD liners and
Breakthrough results with this new metallization scheme are enabled by two
key process steps. The first key process in the scheme is a Ruthenium liner
layer deposited by a CVD process using the TEL Trias Tandem™ system. The
CVD Ru process offers exceptional feature conformality and resistivity in aggressive
damascene features at thicknesses of less than or equal to 2nm (20Angstroms).
The proprietary CVD Ru process and hardware provides excellent productivity
and very efficient use of the Ru precursor. In mass production, the consumable
cost for the CVD Ru process (including pre-clean and barrier processes) will
be the most attractive among all available options. This level of consumable
cost is not achievable with PVD Ru or ALD Ru.
The second key process step in the new metallization scheme is a wet copper
seed process called DirectSeed™ which is deposited in the Novellus SABRE®
Extreme™ electrochemical deposition tool. DirectSeed from Novellus is
a proprietary technology for depositing a smooth, conformal Cu seed layer with
thicknesses of less than or equal to 3nm (30Angstroms) directly on the CVD Ru
substrate. The DirectSeed process eliminates the need for a PVD Cu seed layer
and eliminates the processing challenges with PVD including step coverage, overhang
and feature shadowing. The industry-leading SABRE Extreme Electrofill™
process is also used to deliver perfectly-filled Cu features at the 2Xnm node.
According to Go Okubo, vice president and general manager for the Single Wafer
Deposition Business Unit, Tokyo Electron Ltd, "The achievement of our collaboration
is a breakthrough in terms of realizing two long-awaited technological advancements.
One is the establishment of the innovative integration technology, which assures
copper fill at 2Xnm and beyond, and opens new prospects for reducing line resistance.
The other is the substantial reduction of the process steps without sacrificing
the benefit of low CoC, which will contribute to maximizing our customers' profit.
Achieving this technological breakthrough came by combining the expertise from
TEL and Novellus. We will pursue our relationship to further improve copper
According to Tim Archer, executive vice president for Electrofill and PECVD
business units at Novellus Systems, "TEL and Novellus have joined development
forces to offer an exciting, attractive alternative to the traditional PVD /
Electrofill approach for 2Xnm and beyond. The combination of the TEL CVD Ru
liner and the Novellus Sabre DirectSeed™ copper wet seed and Sabre Extreme
Electrofill offer an extension of copper fill to the finest features while improving
the cost per wafer as well. The partnership of TEL and Novellus also offers
our customers tremendous leverage by reducing or eliminating the development
and integration time and cost that follows the selection of individual processes."