New-Tech Europe Magazine | Q4 2021

Image Source: Chip Design Magazine

Figure 1: A PCB substrate used for microchips packaging

manufacturing and system assembly. The need to comply with so many manufacturers’ design rules, requires compromise, limits the system performance, and creates a significant delay in time to market. PCB Technologies sets new standards of holistic engineering, saving our customers the time and energy required for coordinating between various suppliers. Our All-in-One approach enables combining various materials while tailoring the required properties for the customer's PCB needs. We offer our customers the ability to design and manufacture substrates for microchip assembly, chip assembly, and encapsulation to create a system in package. A true one-stop-shop for any design or project.

W/mK) with low CTE (5-7 ppm/C) can be realized by creating a laminate comprised of copper and refractory metals. In such laminates, copper is responsible for thermal conductivity while the refractory metal ensures low CTE. The actual thermal conductivity / CTE is determined by the relative thickness of each metal. The ability to design and manufacture advanced substrates – including low-CTE heat sinks clears the way for advanced systems, where more than one chip can be mounted onto the same substrate. Forming this System in Package (SIP) allows several types of microchips, from several vendors and produced with different semiconductor technologies, to be assembled on one substrate. The substrate can also include analog devices (e.g. resistors) and miniature PCB line/space enabling chip connectivity with a shorter path thus using a smaller PCB footprint. Furthermore, the substrate enables to stack microchips resulting in a 3D package that is in itself a full system. SiP can be used in any application that benefits from miniaturization- for example, any transmitter/ receiver system- including radars for autonomous vehicles, military radar systems, cellphones, etc. The main component in such systems is

a transmitter/receiver chip, usually GaAs-based. The receiver is a high- power chip, requiring heat dissipation. In addition, the system requires a data processing component and antenna switches, typically realized by Si-based chips. Assembling and encapsulating each of these chips separately might result in large PCB footprint consumption. Furthermore, the electrical connection between chips relies on long interconnects – limiting the system speed and wasting power. Packing all these chips on one substrate means that the whole system area can be reduced by a factor of 4-10. Many analog devices that are needed as part of the circuit can also be mounted on the same SiP – resulting in a smaller, faster system. Another good example is navigation systems, which include micro- electromechanical systems (MEMS) chips as well as data processing and analysis chips. Such systems are becoming widespread and are critical for autonomous vehicles, self- propelled drones, cellphones, etc. Designers normally engage with several vendors for the development of a new system based on SiP. One for SiP circuit design, another for manufacturing, a third vendor for chip assembly and encapsulation, and one or two additional vendors for PCB

Eran Lipp, R&D manager

New-Tech Magazine Europe l 17