Title :
Capacitor over Bitline (COB) DRAM Cell and its Contributions to High Density DRAMs
Author :
Kimura, Shin´ichiro
Author_Institution :
Central Res. Lab., Hitachi Ltd., Tokyo
Abstract :
The capacitor over bitline (COB) cell has significantly contributed to the increase of DRAM density. A simple idea of making capacitors over bitlines changed the memory cell structure and fabrication steps, and enabled the cell to maintain sufficient storage capacitance in ever decreasing memory cell. The COB cell has been proved to be the most suitable DRAM cell structure for this decade. In this presentation, I would like to review the COB cell development and its contributions to the high density DRAMs. Outlook on future cell structures based on the COB cell will also be discussed.
Keywords :
DRAM chips; capacitors; DRAM density; capacitor over bitline DRAM cell; fabrication steps; memory cell structure; storage capacitance; Capacitance; Capacitors; Dielectrics; Electrodes; Fabrication; Hafnium oxide; Joining processes; Laboratories; Random access memory; Silicon compounds;
Conference_Titel :
VLSI Technology, Systems and Applications, 2008. VLSI-TSA 2008. International Symposium on
Conference_Location :
Hsinchu
Print_ISBN :
978-1-4244-1614-1
Electronic_ISBN :
1524-766X
DOI :
10.1109/VTSA.2008.4530807
