Singapore--Semiconductor-research specialist A*STAR Institute of Microelectronics (IME) and Nikon Corporation (Tokyo, Japan) will be setting up an R&D laboratory in Singapore to develop advanced optical-lithography technology for the 193 nm argon fluoride (ArF) excimer-laser wavelength. The intent is to push semiconductor-chip geometries down below 20 nm.

Nikon and IME will extend ArF deep-ultraviolet (DUV) dry and immersion lithography by further developing multiple patterning and directed self-assembly techniques. The partners hope to use the technology to make more-advanced logic, high-density memory, embedded non-volatile memory, high-speed electronics and nanophotonics, and nano-electromechanical systems (NEMS). Nikon has been in the optical lithographic equipment market since the 1980s.

Optical lithography at 193 nm has been around for years and is used, for example, in the production of Intel's current 22 nm Ivy Bridge CPU chips. Going much below 22 nm in feature size is a challenge, although Intel is aiming to hit 14 nm in 2014. When conventional 193 nm lithography optics is used, the idea will be to apply further photoresist and exposure tricks (multiple exposures and so on), relying on the nonlinear properties of resist to give a boost to what amounts to superresolution techniques.

Nikon and IME's other approach -- directed self-assembly -- is a radical departure from conventional lithography; in this technique, nanosized building blocks (such as nanospheres) are made to assemble to create the photomask required for exposure. This is called a "bottom-up" technique, as opposed to conventional lithography's "top-down" approach.

The main challenger to Nikon and IME's research effort will be extreme UV (EUV) lithography, which is now in the R&D stage; it uses light at a 14 nm wavelength and precision mirrored optics to greatly increase optical resolution in a straightforward way (in other words, not relying on nonlinear resist effects). Cymer (San Diego, CA) is developing the light source and ASML (Veldhoven, The Netherlands) the scanning and exposure equipment for this approach (in fact, ASML is buying Cymer). Nikon is also involved in developing EUV systems.