A high-performance thermal paste for power electronics applications

Magna-Power Electronics has introduced Pitel Paste, a high-performance thermal paste for power electronics applications. The first formula introduced, Pitel Paste AZ-01, has been formulated and refined over the previous eight years, balancing thermal transfer performance with ease of dispensing and cost, making it attractive to various electronics manufacturers. The paste is available in seven varying containers ranging in volume from 1ml to 19,000ml syringe, container, and tube packaging support various dispensing methods.

A thermal interface material between two metal surfaces can provide up to two orders of magnitude drop in thermal resistance. With higher power densities afforded by new GaN and SiC wide-bandgap semiconductors, thermal transfer considerations in power electronics are more crucial than ever.

The paste attains a thermal resistance of 6.5 x 10-6K·m2/W (ASTM D5470), which benchmarks void-filling thermal paste performance for power semiconductors, measuring how readily heat can be conducted between two surfaces. A lower thermal resistance permits product designers to attain greater power densities by delivering better heat transfer from power semiconductors to the heatsink. The company evaluated and iterated on its own thermal paste formulation through the lens of power electronics applications. Today, the paste supplies a critical role in the company's ability to provide among the most power-dense programmable power supplies on the market.

"Pitel Paste has been formulated to achieve the ideal balance between thermal, electrical and rheological properties," said Stan Jaracz, PhD, a senior chemical engineer at Magna-Power Electronics. "It is the perfect thermal interface material for all application methods from spatula to stencil, providing excellent thermal transfer properties, with a packaging portfolio that tailors Pitel Paste for many electronics manufacturing processes."

With internal capabilities that comprise sheet metal and heatsink fabrication, CNC machined surface finishing, and power module assembly, the company is uniquely positioned to address power semiconductor heat extraction with a vertically integrated approach. The company will share its thermal paste technical experience and application techniques through a series of white papers. The first white paper, titled 'Thermal Paste Surface Application in Power Electronics Manufacturing', is now offered and discusses various dispensing methods, with considerations for automation, volume precision, placement precision and setup costs.