Japan"s Toshiba plans to speed up its flash memory expansion plans and boost production capacity by 70 percent by June 2008, six months ahead of schedule. Toshiba, the world"s second-largest maker of NAND flash chips, and its U.S. partner SanDisk will push forward ramp-ups at a 600 billion yen ($4.9 billion) plant under construction in western Japan, Toshiba spokesman Keisuke Omori said on Tuesday. Ramping up capacity and driving down production costs is imperative for Toshiba, which is hurrying to catch up to top NAND maker South Korea"s Samsung Electronics Co. Ltd. as chip price falls level off and present attractive margins.