A 130 mm/sup 2/ 256 Mb NAND flash with shallow trench isolation technology
K. Imamiya, Y. Sugiura, Hiroshi Nakamura, Toshihiko Himeno, Ken Takeuchi, Tamio Ikehashi, Kazushige Kanda, Koji Hosono, R. Shirota, S. Aritome, Kazuhiro Shimizu, K. Hatakeyama, Koji Sakui · 2003
Higher density flash memories for mass storage are attractive for application in the audio-video field, for example, in digital cameras and for voice recording. A 100 MB Flash records one hour CD-quality music. Improvements in video compression techniques are expected to realize gigabyte flash, enabling movies on silicon in the near future; a development that is expected to lead to rapidly rising demand for high-density flash. Both the low bit cost due to the small cell size and the high program and read performance are important factors for the high density flash. A NAND flash has potential advantages in those respects. Shallow trench isolation (STI) shrinks bit line pitch to 73% of that in the case of conventional LOCOS isolation, enabling 0.29 um/sup 2/ cell 0.25 /spl mu/m design rules. The 129.76 mm/sup 2/ chip is made possible by using NAND type memory cell and STI.