Toshiba 300mm Wafer Fab

Toshiba Corp. and SanDisk are building a new 300mm wafer fabrication facility at Toshiba’s Yokkaichi operations in Japan. The companies plan to start construction of the new facility, called Fab-4, in August 2006. Initial production operations are scheduled to begin in Q4 2007.

Toshiba will fund construction of the building, while both Toshiba and SanDisk will provide funds for the manufacturing equipment. Fab-4 will be similar in size to the companies’ Fab-3 300mm plant currently also operating at Yokkaichi.

Toshiba has increased its capital-spending budget several times over the last year, partly to fund expansion at Fab-3 and partly to fund Fab-4. In 2005, Toshiba announced an increase in capacity at Fab-3 from 10,000 to 30,000 300mm wafers/month: 40% higher than previously planned. That took an investment of nearly ¥40 billion (about $350 million), evenly shared between the companies. The two companies jointly invested an additional $1.5 billion in February. That should take the output at Fab-3 to nearly 50,000 wafers/month by the second half of 2006.

The companies cited the continued growing demand for NAND flash as the reason for the expansion. Together, the two fabs should meet the demand for NAND flash memory products beyond 2008.

TOSHIBA AND SANDISK JOINT VENTURE

In December 2001, Toshiba and SanDisk announced a Memorandum Of Understanding to consolidate their NAND flash wafer fab manufacturing operations. In December 2002, they announced relocation of their joint FlashVision venture from the Dominion Semiconductor facility in Manassas, VA, to Toshiba’s semiconductor plant at Yokkaichi.

The aim at the time was to increase production capacity and speed time to market for volume production of the companies’ 0.13-micron NAND flash memories. Production at FlashVision Japan started in 2002, with production ramp up in 2003. Toshiba had previously made 0.16-micron NAND flash wafers at the Yokkaichi facility. The consolidation of manufacturing at Yokkaichi streamlined the technology transfer for highly cost competitive MLC (Multi-Level Cell) NAND and 0.13-micron devices.

In 2004, Toshiba and SanDisk began constructing the 300mm fab at Yokkaichi. Mass production began in Toshiba’s financial year 2005 (brought forward from FY2006). The total investment in Fab-3 at Toshiba’s Yokkaichi operations has been around ¥200 billion (nearly US$2 billion) up to the end of FY2005. The facility is operated by FlashVision.

Initial production at Fab-3 used a 90nm process, and this is migrating to the 70nm process jointly developed by Toshiba and SanDisk. Output is equally shared between Toshiba and SanDisk. The fab still has space to expand capacity, and further investment could take output to as high as 62,500 wafers/month.

The 300mm fab is also slated to mass-produce NAND flash memory based on 55nm processes in late 2006. Toshiba now has a monthly capacity of 450 million (counted in 64Mbit parts) NAND flash memory chips. Capacity will be increased to 750 million units when processes shift to 55nm.

Environmentally conscious design reduced emissions of carbon dioxide and perfluorocarbons from the clean room in Fab-3, while the energy consumed in wafer processing is 30% lower than that in Toshiba’s 200mm wafer clean rooms.

As announced, Fab-4 will be similar to Fab-3, which is a five-story building with site area of 24,300m², floor area of 113,000m², and clean room area of 34,500m². There are around 1,950 employees at the site. Total site area is around 312,000m², and total building area is around 180,000m² excluding Fab-3 and Fab-4.

LONG-TERM COOPERATION

Non-volatile NAND flash memory was invented by Toshiba, and stores data for various mobile products including digital still cameras and multimedia mobile phones. The strategic partnership with US-based SanDisk brought the experience of a leading memory card maker with expertise in high-density flash memory and MLC NAND.

SanDisk is the world’s largest supplier of flash data storage products. It designs, manufactures and markets industry-standard, solid-state data, digital imaging and audio storage products. SanDisk is based in Sunnyvale, CA. Flash Partners, Ltd., a Toshiba-SanDisk venture established in September 2004, is 50.1% owned by Toshiba and 49.9% by SanDisk.

The NAND-FLASH market more than doubled between 2003 and 2006. The price of NAND flash chips however dropped dramatically in 2005 (by around 60%). Toshiba said it expects demand will help boost pricing within an acceptable range.

SPECIFICATION – TOSHIBA FAB AT YOKKAICHI JAPAN