Power electronics: SiC and GaN, the new components challenging electronic subcontractors

Not all current electronic components meet the performances of electric vehicle engines. The new SiC and GaN components are the only ones to achieve this to date. However, their performance levels are such that they have a significant impact on the entire electronic production chain, challenging the know-how previously acquired in terms of assembly.

This new generation of components supports a much higher operating temperature of up to 200°C, compared to 125°C for current components. Their range of use is therefore extended, requiring the development and industrialisation of new processes capable of offering all the qualities of electrical and thermal connections as well as resistance levels never previously attained in mechanical fasteners.

Consequently, the methods used until now to connect components onto printed circuit boards or busbars need to be even more effective. Firstly, they must have lower resistance to current flow while also complying with new insulation and thermal transfer constraints to ensure high efficiency of cooling systems and optimal operation. The materials currently used for crimping or screwing, for example, are therefore no longer suited to the needs of these new components.

The performance of the new SiC and GaN components is such that, with the same operating power, product volumes are divided by five. Product weights follow at least the same ratio, as does the sizing of cooling systems, which in some cases are no longer even necessary.

These technological advances meet the fundamental challenges of electric vehicles, as well as those of flying machines such as drones or new-generation aircraft. The same applies to land-travel and seafaring equipment.

The benefits in terms of environmental and conservation challenges are considerable, since these advances offer significant impacts on:

• Reduction in the use of materials, with unprecedented operating yields (due in particular to the five-fold reduction in product volumes at equal power);
• Lower levels of heat loss, thanks to fewer temperature increases, and at negligible levels compared to current systems.

The challenge is twofold: to successfully industrialise these new assembly processes as early as possible and deliver design guides to automotive manufacturers and equipment makers. At the same time, it is necessary to meet applicable standards in terms of industrial production quality and the operating reliability of assembled products. This is a major challenge for our customers and their applications.

The launch of a French electronics consortium, We Network, with such a high level of cooperation and expertise among each of its members is a first in the sector. The three partners began by jointly undertaking a state-of-the-art review of their various assembly methods (alloys used, means of attachment, etc.) before addressing the other phases of the project.

Producing power electronics on an industrial scale entails a new field of competence. The PREMS project enables its members to forge strong relationships with automotive manufacturers and equipment producers at the heart of this challenge.

This is an initiative which is setting future standards in the field of power electronics. At the electronics sector level, the three partners are working on process innovation to achieve new objectives specific to the assembly of components and products related to power electronics.