Product Briefing Outline:
Tokyo Ohka Kogyo Co.,
Ltd. (TOK) and Dow Corning Electronics have jointly developed bilayer
photoresist used for DRAM production applications. The new bilayer
photoresist uses a Dow Corning silicon polymer in the imaging layer to
provide better etch selectivity than other products on the market
today, the company claims. Dow Corning and TOK have had a joint
development agreement since 2002 to develop advanced silicon-based
Photoresist is a light-sensitive material
that becomes either soluble or insoluble after exposure to light,
allowing portions to be selectively removed during subsequent etching
processes. Adding Dow Corning's silicon polymer to TOK's photosensitive
materials enables the use of thinner photoresist layers, which is
claimed to improve pattern resolution and allows smaller circuit
patterns to be transferred onto target wafers without pattern collapse
The new photoresist is
intended to provide a more cost-effective lithography solution by
eliminating the hardmask layer and accompanying process steps required
by multilayer photoresist processes. It can be used for both dry and
immersion lithography, an advanced imaging technology that is gaining
market acceptance for the 45nm node and beyond. TOK has said that it
has already demonstrated the use of the photoresist under immersion
lithography conditions to produce 35nm line/space patterns.
DRAM using both dry and immersion lithography for the 45nm node and beyond.
Customized silsesquioxane resins.
December 2007 onwards.