Advances in the Internet of Things (IoT) have brought about a new era where a whole range of things are connected to the cloud, as well as to smartphones, PCs, and other devices. This was made possible by the advances in semiconductor chips achieved nearly every two years over a period that stretches back into the 20th century. However, the pace of semiconductor chip innovation is beginning to reach its limit. As the chips become smaller, it’s increasingly difficult to manufacture them using existing methods.
Precious metals are in the spotlight as the basis for technologies that can break through those limitations. We spoke to two executives from TANAKA Precious Metals (TANAKA) to get a better idea of how these materials might rescue the semiconductor industry.
Next-generation chips made using ruthenium
One precious metal that is being looked to as a breakthrough material is ruthenium. Ruthenium is already being used to increase the capacity of hard disk storage.
Semiconductor chips are fabricated by connecting transistors and other components with interconnected wiring. One obstacle to innovation is that, as semiconductor chips get smaller, there is increasing contact resistance between transistors and wiring. Electromigration can also lead to deterioration and disconnection.
Solving those problems requires the use of a metal with different properties from conventional copper. According to Takao Enomoto, head of the Chemical Materials Development Department of TANAKA Precious Metals’ R&D Division, one such metal is ruthenium, which minimizes the possibility of electromigration.
When fabricating semiconductor chips, wiring is produced by vaporizing metal wire materials and allowing them to be deposited on the chip’s surface as a thin metal film that serves as wiring. This process is called chemical vapor deposition (CVD).
TANAKA is one of the world’s leading manufacturers of precious metal components for industrial use. The company has been developing its original ruthenium compound for use as the metal precursor vaporized in the CVD process.
Generally, there is almost no limit to the possible combinations of organic compounds and metals. Starting around two years ago, TANAKA began to use computational chemistry to seek out innovative materials. This dramatically reduces the time needed to search for compounds, which has great significance for semiconductor chip scaling. TANAKA also conducts technical research with other firms. For example, Tanaka worked with other firms to pioneer technology to recover ruthenium, remove impurities, and reuse it as a precursor in the CVD process.
Precious metals open up a new future for semiconductor chips
The use of ruthenium for semiconductor chip fabrication is just one example of the potential of precious metals. There are many other ways in which the properties of precious metals could significantly alter the future of semiconductor chips. One possibility Mr. Saito mentions is the use of precious metals to create the next-generation memory for semiconductor chips known as “spin transfer torque RAM,” or STT-RAM. Manufacturing of STT-RAM has already begun, with the ultimate goal of seeing it replace the DRAM memory that is currently in wide use.
Enomoto notes that, using three-dimensional integration technology to vertically stack several completed chips …read more
Source:: Business Insider