Environmental sustainability programme to eliminate lead in future microprocessors
Intel Corporation has announced that its future processors, beginning with its entire family of 45 nanometre (nm) high-k metal gate (Hi-k) processors, are going 100 percent lead-free. The Intel 45nm Hi-k family includes the next-generation Intel Core 2 Duo, Core 2 Quad and Xeon processors, and the company will begin 45nm Hi-k production in the second half of this year.
"Intel is taking a positive stance toward environmental sustainability, from the elimination of lead and a focus on greater energy efficiency of our products to fewer air emissions and more water and materials recycling," said Nasser Grayeli, Intel vice president and director of assembly test technology development, Technology and Manufacturing Group.
Lead is used in a variety of micro-electronic "packages" and the "bumps" that attach an Intel chip to the packages. Packages wrap around the chip and ultimately connect it to the motherboard. Different types of packages are used for processors targeted at specific market segments, including mobile, desktop and server. Package designs include pin grid array, ball grid array and land grid array, and all are 100 percent lead-free in Intel's 45nm Hi-k technology generation. In 2008, the company will also transition its 65nm chipset products to 100 percent lead-free technology.
Intel's 45nm processors not only are lead-free, they also make use of the company's Hi-k silicon technology for reduced transistor leakage, enabling more energy-efficient, high-performance processors. The Road to Lead-FreeFor many decades lead has been used in electronics because of its electrical and mechanical properties, making the search for replacement materials that meet performance and reliability requirements a significant scientific and technical challenge.
Due to lead's potential impact to the environment and public health, Intel has worked for years with its suppliers and other companies in the semiconductor and electronics industry to develop lead-free solutions as part of its long-standing commitment to environmental practices. In 2002, Intel produced its first lead-free flash memory products. In 2004, the company began shipping products with 95 percent less lead than previous microprocessor and chipset packages.To replace the remaining 5 percent (about .02 grams) of lead solder historically found in the first-level interconnect -- the solder joint that connects the silicon die to the package substrate -- in processor packages, Intel will use a tin/silver/copper alloy. It is the way in which Intel will implement these new materials to replace the tin/lead solder that is the "secret sauce" of the company's solution. Because of the complex interconnect structure of Intel's advanced silicon technologies, a great deal of engineering work was required to remove the remaining lead in Intel's processor packages and integrate a new solder alloy system.
Intel engineers developed the assembly manufacturing processes involving the new solder alloys, and were able to accomplish this while still demonstrating the high level of performance, quality and reliability expected of Intel components.
