February 17, 2006 – Nikon Corp. says it has shipped the world’s first production immersion lithography system to a memory chip manufacturer using 55nm process technologies, and for R&D on 45nm devices. The NSR-S609B ArF immersion scanner, with a hyper-NA projection lens of NA=1.07, was shipped last month.
The system uses proprietary “local fill” technology to eliminate scanner-induced immersion defects, without bubbles, water spots, or backside wafer contamination, while preventing evaporation of the immersion fluid to prevent immersion-related overlay problems, the company stated.
The tool also utilizes a two-step “tandem stage” method, with one step to process wafers at high accelerations and scan speeds, and another for calibrating the tool between wafer exchanges. Nikon claims this two-step method has reduced overlay accuracy to <7nm.
Rival ASML has said it would begin volume production of its immersion litho system targeting 45nm chip manufacturing, the Twinscan XT:1700i (NA=1.20), in 2Q06.