Power Electronics Thermal Interfaces (PETI)

Kuprion and Ozark joined forces to propose the use of a novel nanocopper materials technology that allows the use of copper as a surface mount and thermal interface material. This material converts to bulk copper at temperatures around 200 ℃ enabling high operating temperatures of up to 900 ℃. Coupled with Ozark IC’s advances in die attachment techniques and companion electronics, this system provides an ideal solution for realizing high temperature power electronics. Initial tests using commercial LEDs have shown it to be thermally superior to solder running significantly cooler than AuSn enabling a 37% higher efficiency and light output. Bulk measurements revealed an intrinsic thermal conductivity of 277 W/m*K. The material is readily dispensable and stencil printable for die bonding and PCB assembly. The small amounts of additives and surfactants completely evaporate during fusion, eliminating any post cleaning requirements. It lacks a liquid transition state, which eliminates wicking during processing allowing for very close spacing of components and leads / contacts. The paste formulation will be modified to inhibit grain growth at elevated temperature and to reduce CTE to increase stability to thermal cycling for maximize life under harsh operating conditions.