Thin and smooth sub-10 nm metallic lines

by | Jul 7, 2010

Metal lines thinner than 10 nm can be fabricated by electron-beam patterning and hydrogen reduction of metal-naphthenates.

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While the fabrication of extremely thin metal wires is considered an enabling technology in microelectronics applications, researchers have encountered a number of challenges using traditional lithographic and pattern transfer techniques to achieve this goal. For example, depending on the properties of the metal film, the grain size might be comparable to the line width, causing a break to occur at the grain boundary.

Now, researchers in Singapore, South Korea, and the UK have collaborated to produce sub-10-nanometer nickel nanolines using a new patterning/reduction technique. They first deposit a metal-naphthenate on a surface, then pattern with an electron beam. Subsequent reduction in a hydrogen-rich atmosphere produces continuous wires with 7 nm linewidths and low roughness.

The authors expect this method will be applicable to other metal-naphthenates, including iron, cobalt, tungsten, and molybdenum, only limited by metal oxides that are thermodynamically more stable than water and prone to forming metal hydrides.