As a technology-driven manufacturer of bonding wires, Nippon Micrometal is providing new and innovative products to support the ever-changing semiconductor sector.
“My goal is to make Nippon Micrometal a company recognized all across the world.”
Dr. Takashi Yamada, President, Nippon Micrometal Corporation
In the 35 years since it was founded, Japan-based Nippon Micrometal has established itself as a trusted, expert producer of bonding wires for semiconductors, catering for a growing portfolio of industry-leading semiconductor manufacturers. “The majority of our customers are overseas; and these customers are major players globally,” explains Nippon Micrometal’s president, Dr. Takashi Yamada.
“As a company, we have three key strengths, starting with the quality of our products,” Dr. Yamada continues. “Our customers use our wires as the last step in their semiconductor productions, so if the wire bonding were to fail, the whole process must be discarded and would be considered a waste. With that in mind, you can understand why reliability and high quality are essential to our business. Secondly, we provide aftercare to customers and should any issues arise when using our products, we are ready and willing to provide solutions for them. Technological support is one very strong advantage that we provide. Lastly, we conduct R&D in advance and consider potential future trends. With our cutting-edge technology, we develop our products tailored to individual companies’ needs.”
Chief among the next-generation products developed at Nippon Micrometal is the Advanced Copper Wire EX, which allows customers to make major savings. “Copper wire has always had an issue with oxidation, but we overcame this by selecting palladium as a coating material and controlling the palladium metal coating at a nano level,” Dr. Yamada explains. “With our unique wire processing technologies, we succeeded in mass-producing palladium-coated copper (PCC) wire. Gold has been used in bonding wires for 50 years now, but with prices surging, replacing gold wire with PCC wire that is robust against oxidation has been very effective and enabled our customers to reduce costs significantly
“Thirty percent of semiconductor packages still use gold wires, so we continue to work on the further replacement of these gold wires,” he adds.
In addition to replacing gold with alternative materials, a continual focus of Nippon Micrometal’s R&D efforts is the ever-increasing miniaturization of electronic devices. “Miniaturization is having an impact on our products and we need to continuously improve them to cater to the higher densification of semiconductor packages,” the company chief says. “We must make the diameter of the wire smaller and keep improving our wire technology. It is vital that we keep ourselves updated with all the advancements in the semiconductor field.
“When the transistor was first invented, there was only a single wire on a surface. But now we see a semiconductor package that requires more than 1,500 wires. It is extremely difficult to keep those wires from touching each other and causing a short circuit. Wires are now down to the size of 16 microns and even smaller, which would be less than one-fourth the thickness of a strand of human hair.”
Nippon Micrometal is also committed to keeping pace with the evolution of the materials used to make semiconductors. “Currently, our copper, silver, gold and aluminum wire products are focused on silicon-based semiconductors which are used for a more high-density type of semiconductor,” Dr. Yamada says. “On the other hand, in the area of power semiconductors, we are anticipating a switch to new technologies, such as silicon carbide (SiC) technology. For example, with the transition to electric vehicles, SiC technology will be essential for a transition from a 400-volt to an 800-volt battery charging system. We are focused on developing new types of wires to meet the new challenges in power semiconductors.”
As well as bonding wires, Nippon Micrometal supplies solder balls used in the production of semiconductor packages, with the tin-silver-copper-nickel LF35 Micro Ball a headline product. “We started developing the LF35 when mobile phones became popular – it has high reliability and connectivity,” Dr. Yamada says. “What we have invented is a unique composition of metal based on our own technology.”
International expansion is a major focus at Nippon Micrometal, which since the turn of the millennium has established subsidiaries in China, Malaysia and the Philippines. “We would like to continue to expand overseas, and ultimately establish a base in each locality that we operate in,” Dr. Yamada says. With a number of countries eager to grow their domestic production of semiconductors, he is confident that the company will benefit from this drive: “Currently, the production of semiconductors is centered around Taiwan and China, but by diversifying, we are creating a very advantageous situation in terms of our business continuity plan. We find no negativity in the expansion of local production and hope to find more opportunities for ourselves to grow.”