Problem: The Applied Tetra Reticle Clean system is
claimed to be the first mask cleaning system to achieve zero damage and
99 percent particle removal efficiency (PRE) on advanced masks for dry
and immersion technologies. The Tetra Reticle Clean combines a mask
clean chamber and a plasma dry strip and conditioning chamber on one
platform to address the full range of mask cleaning challenges from
photoresist strip to removing post-etch residues and particles while
preserving the integrity of the photomask.
Solution:
The system is unique in its streamlined mask handling, integrated
dry/wet processing capabilities, and throughput at least double that of
equivalent mask cleans products. The mask is handled only to enter and
exit the clean chamber, where it is stripped, cleaned, rinsed, and
dried without mask flipping. Tetra Reticle Clean is claimed to be the
only system employing ‘Uniform Cavitation Megasonics,’ which
distributes energy evenly over the entire mask surface, avoiding the
damage-causing spikes generated by traditional point-source megasonic
cleans. The clean chamber is designed for cleaning the front and back
of the mask simultaneously, using different chemistries if necessary
with no possibility of mixing. NanoDroplet Technology further enhances
damage-free cleaning using an overhead nozzle designed to create
uniform high-momentum "nanodroplets" and kinetic energy. Sulfur-free
stripping followed by advanced cleaning chemistry outperforms standard
chemistries in preserving optical properties of the mask and preventing
haze formation.
Applications: Integrated dry/wet processing for all mask types and feature sizes through 32nm and beyond.
Platform:
Uses proprietary ‘Uniform Cavitation Megasonics’ (UCM) technology as
well as ‘NanoDroplet’ technology. The system can be configured with
multiple processing modules, offering mask makers the capacity to
eliminate processing bottlenecks and reduce cycle times.
Availability: April 2008 onwards.