Title :
A 0.15 /spl mu/m KrF lithography for 1 Gb DRAM product using highly printable patterns and thin resist process
Author :
Ozaki, T. ; Azuma, T. ; Itoh, M. ; Kawamura, D. ; Tanaka, S. ; Ishibashi, Y. ; Shiratake, S. ; Kyoh, S. ; Kondoh, T. ; Inoue, S. ; Tsuchida, K. ; Kohyama, Y. ; Onishi, Y.
Author_Institution :
Microelectron. Eng. Lab., Toshiba Corp., Yokohama, Japan
Abstract :
In order to realize the 1 Gbit DRAM product, 0.15 /spl mu/m photolithography will be necessary. Recently, off-axis illuminations and phase shift masks have been studied for realizing 0.175-0.25 /spl mu/m lithography. Even if these technologies are used, 0.15 /spl mu/m lithography is difficult. Investigating various lithographic approaches by optical simulation including the effect of photoresist processing, we found that a thin resist (300 nm thick), highly printable memory cell patterns, and optical proximity correction are very useful for realizing the 0.15 /spl mu/m rule DRAMs with KrF laser stepper (NA=0.6).
Keywords :
DRAM chips; laser materials processing; phase shifting masks; photoresists; proximity effect (lithography); semiconductor process modelling; 0.15 mum; 1 Gbit; 300 nm; DRAM; KrF; KrF laser stepper; KrF lithography; highly printable memory cell patterns; highly printable patterns; off-axis illumination; optical proximity correction; optical simulation; phase shift masks; photolithography; photoresist processing; thin resist process; Capacitors; Dry etching; Laboratories; Lighting; Lithography; Microelectronics; Plugs; Random access memory; Resists; Topology;
Conference_Titel :
VLSI Technology, 1998. Digest of Technical Papers. 1998 Symposium on
Conference_Location :
Honolulu, HI, USA
Print_ISBN :
0-7803-4770-6
DOI :
10.1109/VLSIT.1998.689209
