Tantalum and Niobium-Based Capacitors

Introduction.- 1:  Major Degradation Mechanisms.- 2: Basic Technology.- 3: Applications.- 4: Conclusion.

Yuri Freeman received his master's degree as engineer-physicist from the renowned school of Thin Solid Films at the Kharkiv Polytechnic Institute in Ukraine. He graduated among the first in his class and hoped to continue his work in academia. However, as it was still Soviet Union times and graduates were "distributed" often contrary to their choices, Yuri was sent to work for SCB ELITAN, a developer and producer of tantalum capacitors. At first Yuri thought sadly: "What could be more primitive than a capacitor with two plates separated by a dielectric?" He realized only later that his random assignment was an incredible opportunity for a scientist and an engineer! The change started with his involvement in the development of niobium capacitors to substitute tantalum capacitors, enforced by a shortage in tantalum in former Soviet Union. Comparison of the degradation mechanisms in tantalum and niobium capacitors became the topic of his Ph.D. in solid-state physics.

Shortly after the collapse of the Soviet Union, SCB ELITAN was closed and Yuri started his work for Sprague-Electric later Vishay-Sprague, the original manufacturer of solid tantalum capacitors. After several years with Vishay Sprague, where Yuri was promoted to principal scientist, his facility in Sanford, Maine, USA, was closed, and manufacturing moved overseas. While Yuri was looking for a new job, his Siberia-born wife fell in love with sunny South Carolina, and that's how Yuri ended up at KEMET Electronics, a global producer of tantalum capacitors. This turned out to become the best part of his career with the most challenging projects and the industry's best team to work with. Now, Yuri is a Fellow/VP, director of strategic development in tantalum at KEMET Electronics. As an adjunct professor, he is also teaching science and technology of the electronic components at the Clemson University.