Isolation merged bit line cell (IMBC) for 1 Gb DRAM and beyond

The Isolation-Merged Bit Line Cell (IMBC) structure was investigated with 0.20 /spl mu/m advanced Deep UV lithography as a candidate cell structure for 1 Gb DRAM and beyond. Better photo margin owing to the improvement of bit-line and global topology, easy formation of cell capacitor, simple process and better process margin were accomplished in IMBC. The electrical characteristics of IMBC was comparable to that of the conventional Capacitor Over Bit line (COB) cell. Moreover, the bit line coupling noise was significantly reduced in IMBC compared with COB. Thus, IMBC is a promising cell structure for 1 Gb DRAM and beyond.