mSAP: The New PCB Manufacturing Imperative for 5G Smartphones (.PDF Download)

Manufacturers of consumer electronics are under ever-increasing pressure to design the sleek, compact devices that customers covet, balancing form and function in a manner that differentiates their products in a crowded and competitive marketplace. Nowhere is this truer than in the smartphone market, where corporate fortunes can rise and fall on the success of their newest generation of phones.

When it comes to smartphone designs, every millimeter of space savings achieved within the device enclosure can unlock significant value for the end customer. It makes possible the use of larger, higher-resolution displays, bigger batteries, and more sophisticated processors and components. All of this enhances the device’s feature set, and improves the overall user experience.

These form-factor-driven design pressures have been relieved in part via the increased use of high-density interconnects (HDIs), which enable more functions per unit area than conventional printed circuit boards (PCBs). Leveraging finer lines, thinner materials, and laser-drilled vias, HDIs have played a crucial role in the ongoing miniaturization of smartphones and their embedded subsystems.

But as we evolve from 4G LTE to next-generation, 5G-compatible smartphones, the PCB industry’s approach to HDI manufacturing must also evolve. Massive-MIMO (multiple-input multiple-oOutput) antenna configurations and increasingly complex RF front-ends will expand the RF content footprint within the 5G smartphone, and the processing power needed to support the staggering volume of 5G data will likely impact battery capacities and geometries, among many other factors. As a result, despite increased I/O demands, the amount of available space for HDI PCBs within 5G smartphones will be significantly reduced.

Moreover, the higher frequencies inherent to 5G will require much stricter impedance control. If not formed with extreme precision, the thinner traces of HDIs can introduce increased risk of signal degradation and data-integrity lapses.

Addition and Subtraction

PCB manufacturers can overcome these challenges by utilizing a modified semi-additive process (mSAP). Commonly used today in IC substrate production, mSAP is poised for widespread adoption in the advanced HDI PCB manufacturing industry.