Striving to become the world's benchmark factory
Hiroshima Plant, a world-class semiconductor production plant, operates a 300 mm line with a capacity of 120,000 wafers per month. To accomplish its goal of becoming the world's benchmark factory with the world's lowest manufacturing costs, the plant is addressing the following three key issues:
- Lowering wafer costs
Improving productivity and lowering energy use, material use, and the number of processes - Lowering chip costs
Improving yields and switching to next-generation products with more miniaturized designs - Smoothly ramping up mass production of next-generation products
Utilizing expertise gained in the past to achieve smooth preparations and product launches
Hiroshima Plant will continue to pursue these timeless themes in the future as Elpida Memory's only domestic mass-production factory in charge of front-end processing.
Achieving the world's lowest environmental impact
In addition to achieving the world's lowest manufacturing costs, Hiroshima Plant is working to achieve the world's lowest environmental impact. On the 300 mm line, engineers are aggressively pursuing productivity improvements, product miniaturization, energy savings, and reduced raw material consumption as part of efforts to address the three key issues listed above. As a result, the facility successfully improved its environmental factor as defined by Elpida Memory by approximately 3.5 times during the two-year period from FY2006 to FY2008. Going forward, the plant will continue to pursue aggressive improvements in order to achieve the world's smallest environmental footprint.
Change in environment factor
Definition of environment factor
The environment factor is derived by dividing environmental efficiency for the target fiscal year by environmental efficiency for the baseline year. Environmental efficiency is defined as the result of dividing the total number of shipped bits*1 (bits) by the associated environmental impact*2 (kg-CO2).
*1 No. of shipped wafers x no. of bits per wafer.
*2 CO2-equivalent of energy, chemical, gas, and PFC emissions. Chemicals and gases represent manufacturing stage emissions.
Initiatives to prevent global warming
Installing a cogeneration system
Hiroshima Plant has installed one of Japan's largest*3 cogeneration systems in order to reduce its greenhouse gas emissions. Cogeneration systems are an efficient means of generating electricity while making effective use of the waste heat given off in the process, for example harnessing it to heat and cool plant facilities. Hiroshima Plant installed a cogeneration system in FY2002 and began use of a new system with a high-efficiency gas engine in December 2005. With current output at more than 100,000 kW, the system, which covers 70% to 80% of the factory's electric power needs, is one of the largest of its kind in Japan. Compared to plant operation before its installation (i.e., using exclusively purchased electric power and boiler steam), the system yields a 26% savings in CO2 emissions.
*3 Reflects the results of a FY2008 investigation by the Center for Promotion of Natural Gas.
Changes in CO2 emissions
Reducing PFC gas emissions
HFCs, PFCs, and SF6, all of which are targeted for reduction by the Kyoto Protocol, play an essential role in semiconductor manufacturing. These substances have extremely high global warming potential, and we have been working for some time to reduce associated emissions. From FY2006 to FY2008, we installed combustion abatement equipment on individual production systems and successfully reduced CO2 emissions by 147 kt-CO2 by increasing the number of such systems in use. However, product miniaturization has driven increases in PFC gas consumption, and FY2009 emissions are expected to reach around 280 kt-CO2. For this reason, the plant plans to install a large-scale, across-the-board abatement system during FY2009. Through this approach, the facility is seeking to meet an FY2010 target of 200 kt-CO2.
Changes in PFC emissions
