Leti, innovation
for industry
Home
>Discover Leti
>Leti's research
>Basic technologies
> LithographyLithography
Contact: Serge Tedesco (serge.tedesco@cea.fr)
Advanced lithography applies new tools to an old problem
Further increases in integrated circuit density depend on continued improvements in lithography. Leti, like the industry as a whole, is pursuing alternatives from advanced deep ultraviolet exposures to massively parallel electron beam writing.
Today, lithography using deep ultraviolet (193nm) allows the realization of sub-32nm structures. By 2013, transistor half pitch will drop below 32nm. To reach these objectives, while limiting manufacturing costs, Leti is working on several aspects:
- improved resist characterization and better device metrology
- the stability of resist components under process conditions to minimize outgassing and leaching
- the development of new metrology references to CD measurement accuracy near the limits of CD-SEM resolution.
-Printing sub-32nm structures with 193nm light with double-patterning
This approach reduces the burden on photomasks and exposure systems by substituting two relaxed-dimension pattern transfer steps for one more aggressive step. In partnership with NIKON and Dow Advanced Materials, Leti is studying an industrial procedure capable of tolerating additional processing, at a lower cost, before the final pattern transfer to the wafer.
-Electron-beam direct-write (EBDW) lithography
With no photomask needed, this technique significantly reduces manufacturing costs. So far, EBDW has struggled to meet the throughput requirements of high- volume production. At Leti, we believe that EBDW can provide flexibility for prototyping as well as a viable manufacturing solution if throughput issues are solved. In collaboration with Mapper Lithography, Leti has agreed to launch IMAGINE, the first international consortium focused on multibeam EBDW development. The program aims to reach throughput of 10 wafers per hour per exposure module to compete with other mask lithography systems by 2012-2014.
|
|