Researchers demonstrate electrical advantages of direct CU etch scheme for advanced interconnects

May 20, 2015
Figure TEM section of copper etched lines encapsulated by SiN cap layer.

Today, at the IEEE IITC conference, nano-electronics research center imec and Tokyo Electron Limited (TEL) presented a direct Cu etch scheme for patterning Cu interconnects. The new scheme has great potential to overcome resistivity and reliability issues that occur while scaling conventional Cu damascene interconnects for advanced nodes.

Aggressive of damascene Cu interconnects leads to a drastic increase in the resistivity of the Cu wires, due to the fact that grain size is limited by the damascene trenches, which results in increased and surface scattering. Additionally, the grain boundary negatively influences electromigration. When scaling damascene Cu interconnects, reliability issues occur because the overall copper volume is reduced and interfaces become dominant. Imec and TEL have demonstrated the feasibility of a direct Cu etch scheme to replace the conventional Cu damascene process.

A key advantage of the direct Cu etch process is that it systematically results in larger grain sizes. Moreover, electromigration performance is preserved by applying an in-situ SiN cap layer that protects the Cu wires from oxidation and serves as the Cu interface.

Explore further: Imec demonstrates CMOS integrated poly-SiGe piezoresistive pressure sensor

Related Stories

NEC Develops New Full Low-k Cu-interconnect Structure

December 13, 2007

NEC have developed a new Silica-Carbon Composite (SCC) film capable of blocking Cu-atom diffusion into the dielectric films of LSI interconnects. Use of the SCC film establishes an ultimate full-low-k (FLK) Cu interconnect ...

Stressing out copper TSVs with temperature

September 25, 2014

In the past, microelectronics were essentially a two-dimensional affair based upon flat integrated circuit chips connected to each other. Then, engineers opened up the third dimension, with integrated circuit chips stacked ...

ACOG: Intrauterine device insertion linked to weight loss

May 7, 2012

(HealthDay) -- Women who undergo postpartum or interval insertion of Levonorgestrel-releasing Intrauterine System (LNG-IUS) or Copper T 380A (CU-T) intrauterine devices experience weight loss in the two years following insertion, ...

Recommended for you

Old, meet new: Drones, high-tech camera revamp archaeology

November 24, 2017

Scanning an empty field that once housed a Shaker village in New Hampshire, Jesse Casana had come in search of the foundations of stone buildings, long-forgotten roadways and other remnants of this community dating to the ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.