Supply Chain Collaboration Required for Greener Fabs
Significant energy savings and greenhouse gas reduction in fabs require close collaboration between chipmakers, equipment providers and subsystem providers, according to speakers at the EHS Forum at SEMICON Korea on January 31. Speakers from Samsung Electronics, Hynix Semiconductor, TI, Applied Materials, TEL, Edwards Korea and Clean Systems Korea provided critical insights into the industry’s leading energy savings and emission reduction strategies, as well as opportunities and challenges.
Mr. Sang Yoon Jung of Samsung began the session providing an overview of Samsung’s corporate commitment to greenhouse gas (GHG) reduction and the Korean government’s commitment to combating climate change. Greenhouse gas emissions of primary concern are perfluorocarbons, trifluoromethane (CHF3), nitrogen trifluoride (NF3), and sulfur hexafluoride (SF6)—collectively termed perfluorocompounds (PFCs). While semiconductor manufacturing accounts for only 3% of the Korea’s greenhouse gas emissions (compared with the steel industry’s 32%), the industry is rapidly growing and every company has responsibilities to protect the environment, said Mr. Jung. In addition to highlighting the Korean government’s policies and goals, Mr. Jung provided a thorough of summary Samsung’s PFC reduction strategies involving using alternate gases, abatement programs (PFC conversion or destruction), and process optimization. The World Semiconductor Council has committed to reduce PFC emissions 10 percent below their 1995 baseline by 2010. Samsung has been very successful in replacing 80% of their PFC gas since 2007 and has improved abatement efficiency above 90%.
Samsung is currently implementing a “Green Design” program for new fabs, targeting a 30% reduction in energy use through waste heat recovery, facility improvements, and energy efficient equipment. Mr. Jung emphasized the need for supply chain collaboration and urged equipment makers to do more in energy efficiency and PFC reduction.
Mr. Seoul Jong Ko of Hynix described his company’s Clean Development Mechanism (CDM) Project, the first of its kind in the world. CDM is one of the Kyoto Protocol’s mechanisms aimed at helping industrialized countries meet their greenhouse gas reduction targets. It allows public or private entities from countries with emission reduction targets to invest in emission reduction projects in developing countries. The entity then earns emission reduction credits (known as “certified emission reduction units” or CERs). These credits can be applied to domestic emission reduction targets or sold to other interested parties.
Shigeito Ibuka of Tokyo Electron and past winner of the Karel Urbanek Memorial Award given for long-standing dedication to the advancement of SEMI Standards, provided an overview of TEL’s environmental programs that have been widely recognized by the Nikkei Environmental Management Survey and other sources. TEL’s energy saving initiatives have reduced the amount of energy used per wafer area to only 35% from 2000 levels.
In a presentation that revealed many of the most prominent energy use and saving opportunities impacting the industry, Jang Hun Joo of Edwards Korea discussed the critical power consumption variables in vacuum pumps. Process tools currently account for approximately 40% of the total energy consumption in fabs today, and vacuum pumps consume an estimated 52% of that total. Reducing energy consumption in vacuum pumps is difficult, involving complex interrelationships between compression, pumping speed, inlet and outlet pressure, and other variables. Newer semiconductor manufacturing technologies such as low-K and high-k process and low temperature PECVD are also increasing pump power requirements. Mr. Joo described techniques to reduce power consumption including lower exhaust pressures, multistage pumps, inverter driving, higher efficiency motors, variable speed motors, and proximity pumping (pump location). Pump-idle mode opportunities also provide significant power saving opportunities, but require open collaboration between equipment manufacturer, chip makers and pump suppliers, often difficult with highly propriety processes. Pump power consumption could be reduced by as much as 50% if appropriate technologies were utilized and all variables were optimized, representing a major untapped opportunity for energy saving in today’s fabs.
Sang Jun Lee from Clean Systems Korea also pointed to the difficulty in synchronizing processes, tools and abatement systems for energy efficiency due to intellectual property concerns. He recommended establishing a research consortium or working committee that would explore ways to optimize energy efficiency without compromising proprietary needs.
Norm Armour, corporate vice president at Applied Materials, provided an overview of Applied Materials wide-ranging sustainable development programs and the critical role that high technology is playing—both positive and negative—in global climate change. In addition to Applied’s growing renewable energy business in PV, fuel cells, solid state lighting and other areas, they have established a development methodology—Design for Environment or DfE—which is used throughout the product life cycle on all their products. DfE consists of energy efficient design and application, resource conservation, recycling and other considerations in the planning, design, and budgeting for new and established products.
In PFC reduction, Applied also follows the “Optimize-Substitute-Abate” strategy. They have implemented many techniques including remote cleaning, chamber diagnostics, efficient coolers and heat exchangers, and incorporation of new chemistries to reduce PFC consumption. The company offers a range of abatement systems and believes as a turnkey supplier they can offer improved energy performance through integrated process design.
Tim Yeakley of Texas Instruments concluded the day’s presentation describing TI’s enormously successful sustainable development and GHG reduction programs. TI established several teams to attack energy use covering all aspects of the company’s operations. Since 2002, TI has completed 37 projects with an average payback per project of only 1.3 years. TI has employed a range of actions including chiller optimization, variable frequency drives, pump replacement, waste recovery, water reclamation and POU chiller replacement to pull ahead of WSC targets for PFC reduction. They are currently implementing additional techniques such as using idle-mode protocols, high-efficiency pumps and point-of-use abatement efficiencies.
Concluding the day and reinforcing a theme that was emphasized in several presentations, Mr. Yeakley said that significant opportunities exist for equipment suppliers to help their customers achieve financially-sound energy and GHG reductions. The technology is available today to radically improve the carbon footprint of today’s fabs. By working with customers and suppliers, finding ways to overcoming proprietary concerns to achieve process efficiencies, using appropriate standards such as SEMI S23, and collaborating on other resource-saving opportunities, the semiconductor equipment and materials suppliers can improve their bottom line and help save the planet.
For more information on EHS activities and programs at SEMI, visit www.semi.org/ehs.