by Richard Otte, CEO – Promex Industries Inc.
MPD: The fifth generation of cellular is rapidly approaching and the immense scope of 5G seems almost certain to present significant opportunities for the RF and microwave industry. What is your perspective on this issue?
Large-scale commercial deployment of 5G wireless communications technology is expected to begin in in 2020. Which means that the development of 5G systems, subsystems and components destined for defense and industrial applications is already underway. With research firms estimating annual revenues for 5G services and products of close to $250 billion by 2025, it’s no wonder manufacturers are racing to be first to market. Unfortunately, this creates a cart-before-the-horse scenario for RF and microwave design engineers, as 5G standards have yet to be established and there’s no global consensus on spectrum use.
Just as daunting as designing complex 5G chipsets without clear specifications is choosing the assembly process to produce the ICs and systems. In addition, the added functionality enabled by 5G will result in additional sensors, devices and components to provide those functions. Assembly of this broader range of parts will involve more complex steps to accurately locate and join components, control adhesive fillets, create solid interconnects, seal joints to prevent liquid leakage, and more. While surface mount technology (SMT) is the most conventional assembly process, many current and new specialized components cannot tolerate SMT’s high temperatures, cleaning processes, handling, etc.
At Promex, we solve this challenge for our OEMs by using what we call “mixed assembly.” We combine SMT with specialized processes such as chip-on-board (COB), flip chip, precision die attach, specialized sealing or encapsulation, micron tolerance optical component attach, sealing of liquid joints, geometry control for RF devices, low temperatures (below 100º C), and more.
Setting up a manufacturing facility to accommodate mixed assembly is not for the faint of heart or thin of wallet. Each process step requires extensive engineering experience. Engineers must also be familiar with a wide variety of materials and be well versed in mechanical and thermal design. They need to know about the latest fixturing developments. And most important of all, they must be acquainted with the many evaluation methods used to ensure process control and high yield.
In addition to engineering experience, mixed assembly also requires a substantial investment in equipment. For example, in addition to conventional SMT lines, accommodating the wide variety of parts suggested above requires equipment to do die attach material dispense, die placement and wire bonding. Then there’s the specialized equipment and processes for encapsulation, drying, thermal and UV curing, custom fixtures at multiple stages, singulation equipment and test systems.
As an EMS provider, the investment in mixed assembly has been well worth it. Every day we help our OEM customers bring products from proof of concept to full production in the fastest and most cost-efficient way possible. When they come to us with designs for enhanced functionality, including 5G, Promex is ready.