Electromobility and automated driving are the two defining trends in the automotive industry with high growth potential, but also technological challenges. For example, hybrid and/or electric powertrains require, among other things, efficient power electronics for the major subsystems such as inverters, on-board chargers or DC/DC converters.
Finally, the implementation of electromobility also requires efficient, space-saving and reliable connection and packaging solutions. On the other hand, new high-performance sensor systems with sensor fusion and high-speed communication are required along the way to autonomous driving, all whilst maintaining functional safety and security. AT&S can help address these automotive challenges with its connection and packaging solutions.
Electromobility continues to make headway, driven by legal requirements in all key regions - led by China. To date in the EU, has the target of 95g CO2/km has been the fleet average for 2021. According to a recent EU compromise, new cars in the EU are to emit another 37.5% less carbon dioxide by 2030 than in the comparable year 2021.
This cannot be achieved without high-voltage electrification and mild hybrid vehicles with a 48V on-board power supply - and this is where efficient power electronics play a central role. AT&S expects above-average growth in electromobility applications over the next few years and is focusing here amongst other things on embedded power technologies – in other words, the embedding of power semiconductors such as MOSFETs in PCBs.
Key benefits of ECP (embedded component packaging) over conventional PCB assembly, include significant miniaturisation thanks to higher integration, improved reliability and superior thermal performance. In addition, ECP facilitates integrated EMI shielding and supports the adaptation of different coefficients of thermal expansion (CTE) for rapid and easy system integration.
As silicon-based solutions slowly reach their limits, the use of wide-band gap materials such as GaN promises more efficient power conversion, with higher efficiency and higher power density. Working closely with partners, AT&S has successfully reduced both the dimensions and the cost of these new components, thereby contributing to the faster adaption of the new technologies.
Automated driving requires high speed communication and sensor fusion
The second megatrend in the automotive industry is automated driving. Automated or autonomous driving constitutes a great potential for the microelectronics industry. By way of illustration, the PCB market for these applications is currently growing at around 5.5% per annum. By 2020, the proportion of costs of electronic components in cars is expected to rise to 35%, and even to 50% by 2030.
With the increasing degree of automation and thus more sophisticated advanced driver assistance systems (ADAS), the need for sensors and different sensor technologies is also increasing in cars. Whilst a combination of camera and radar systems is sufficient up to level 2, from level 3 LIDAR also plays a crucial role.
Due to the ever higher frequencies such as for RADAR, the traces on the circuit boards must also be regarded as RF components and designed accordingly. AT&S has developed PCBs that deliver performance in the frequency range up to 80GHz. For example, these technologies form the basis for RADAR components (long-range radar with 77/79GHz) in advanced driver assistance systems – an indispensable prerequisite for autonomous driving.
The key criteria is a fast, interference-free signal transmission with minimal losses. The losses can be divided into dielectric, resistive, reflection-based and losses generated by emissions. For example, the RF signal in the PCB is influenced by various parameters such as conductor length, base material (loss factor and dielectric constant), reflections due to drilling, impedance matching, crosstalk and interference from external sources (EMC shielding).
AT&S is working on new materials to further reduce the dielectric constant and the loss factor. Other solutions include for example very thin copper foils with low roughness (with sufficient adhesion) for maximum speed or asymmetric hybrid or sandwich structures (e.g. FR4 for the digital layer and ceramic materials such as PTFE for the high-speed layer) for cost-effective PCB technologies up to frequencies of 80GHz.