Transatlantic Co-operation On 157nm
The partners believe that all major hurdles in the development of 157nm lithography have been overcome, a process facilitated by ISMTs early work in building the needed157nm infrastructure. However, considerable work still lies ahead if 157nm lithography is to be adopted in time.
Important engineering efforts remain with respect to full-field imaging, uniform reticle and pellicle printability, and resist technology. Resist technology for 157nm is now entering a stage of formulation and process development, but critical issues such as the delay stability, line edge roughness and etch resistance, need to be resolved before volume use for semiconductor device manufacturing will be feasible.
Much of the required work is planned to come out of IMECs 157nm industrial affiliation programme (IIAP) over the next few years. This programme is due to ramp up to full speed in Q2 of this year. At that time, the worlds first 157nm full-field scanner (ASMLs Micrascan VII) is to become operational at IMEC.
A consortium of IC manufacturers, equipment suppliers, as well as resist suppliers and mask shops has already been established. International SEMATECH has agreed to join a major portion of this program.
The research is to be carried out by IMEC employees and industrial assignees from the partner companies and International SEMATECH on the following topics:
* Hard pellicle printing: understanding and requirements for 65nm imaging
* Reticle handling with special attention to organic contamination removal (through 172nm ozone cleaning)
* Monitoring procedures and contamination/purging requirements for stable imaging on full-field scanners
* Resist integration in process flows for critical 65nm node layers
* Continuous resist benchmarking
* Reticle defect printability issues
