Expanding resist process latitude with shortened develop time

Highly accurate CD control of 3 nm or less by 3/spl sigma/ is required in 2004 and afterwards according to the 2001 edition of ITRS in lithography. Higher NA exposure and shorten exposure wavelength for shrinking CD have drastically narrowed resist process latitude such as DOF and exposure latitude (EL), which make the CD control difficult. In this paper, we describe effects of shortened develop paddle time as short as 3 seconds on the resist process latitude for chemically amplified ArF resist. Two kinds of commercially available ArF resist based on the methacrylate copolymer were exposed with ArF excimer scanner interfaced to DNS track SK-2000. A slit scanning develop nozzle system was employed to supply 2.38% TMAH developer solution on the resist. We express the process latitude with a new approach so that we can grasp a transition of resist process performances on the developing time clearly.