There was a presentation on the increased role of advanced back-end technologies for next-gen devices, from Ruurd Boomsma, CTO, Besi, at the recently held Global Semiconductor and Electronics Forum 2020.
BE Semiconductor Industries N.V. (Besi), headquartered in the Netherlands, has best-in-class equipment, such as die bonding, multi-module, flip chip, TCV, hybrid bond, etc.
Ruurd Boomsma said that the end user markets are mobile Internet with 5G ramp-ups underway, computing, with digital society accelerating, automotive, where development continues, and industrial, such as energy efficiency and green energy. Mobile accounts for 32 percent of Besi’s revenue, computing at 22 percent, automotive at 17 percent, and industrial at 9 percent.
The ever increasing apps are driving exponential growth in data generation. This requires better data transfer, computation, and data storage. All of these are driving miniaturization, efficiency and improved performance per cm3 and W. There are more compact and higher contact densities. From wire bond, we have now moved to hybrid bonding. Besi and Applied Materials announced a joint development program for new die-based hybrid bonding in October 2020.
The new Center of Excellence will be located at Applied’s Advanced Packaging Development Center in Singapore, one of the industry’s most advanced wafer-level packaging labs. It enables foundational building blocks of heterogenous integration in a 17,300-square-foot Class 10 cleanroom with full lines of wafer-level packaging equipment. The CoE will provide customers a platform to accelerate development of custom hybrid bonding test vehicles, including design, modeling, simulation, fabrication and testing. Customer work will start in Q1-2021.
In mobile, 5G mass market rollout is happening. There are new 5G phones with better performance. There is the rollout of new 5G infrastructure, as well. By 2025, at least 2.8 billion new subscriptions are forecast.
There are more advanced packaging solutions now available. The 5G phone is very dense. It requires more integration, SiP, fan-out wafer-level packaging (FOWLP), etc. Examples are optical systems that are becoming very complex, and RF front part advanced double-sided SiP packaging. All of these have to be mounted very precisely. Some examples of Besi’s systems in mobile include ESEC 2100 series, Datacon EVO series, and LM molding series.
Computing is another world, and demands more powerful and efficient devices. Next-gen processors are more powerful and energy-efficient. Advanced packaging is the key enabler for leading-edge devices. Advanced packaging is also the key element in the various semiconductor industry roadmaps, such as TSMC, Intel, and Samsung.
At the ECTC 2020 conference, thermo compression bonding by imec, Belgium was discussed. It uses the Besi 8800 TCB advanced systems. imec has done TCB with 7uM and 5uM pitch. There are 16 stacked dies with 20uM patch.
Next-gen TCB systems are in development. These are die to substrate and die to wafer, memory and logic configurations, increased accuracy, larger die and thin die capabilities, advanced tilt control/warpage control, protective atmosphere low gas usage, and different material feed-in options.
Hybrid bonding is the next bonding and contact technology. Contact density has been increasing with pitches scaling sub 10um. Advantages of hybrid bonding include more contacts per mm2 allowing for much higher bandwidth density. There is no underfill between die and wafer, or die and die, giving shorter contact distances and better signal integrity.
Better thermal bonding is due to direct surface-to-surface bonding. There is lower energy per bit and excellent reliability. There is lower stacking height for stacked DRAM like HBM 5. New device structures and combinations are possible.
Besi has also developed an advanced hybrid bonding system. There is active alignment control while bonding. There is transfer molding for wafer-level molding.
In automotive, electrification will drive growth. Electrical car sales have been growing strongly. Electric infrastructure investment has also been increasing. The increase in EV volumes will generate substantial growth in power devices. By 2040, the EV market will be larger than the conventional market. Many new EV models are being introduced containing higher content of power devices.
New, advanced packages are also emerging. In power devices, most bonding is done by soldering for better heat transfer. Besi has high market share in soft solder bonding. It is working on the next-gen soldering systems, the 2100. It is also enabling Pb-free solder technologies. The AMS-X is a new molding system for power apps. Besi has also supplied in plating for more precise apps.
He added that assembly/backend technology is becoming more critical in further miniaturization regarding higher precision. It is also delivering low overall costs and high yields. Besi has actively developed equipment for high precision die placement and bonding. Hybrid bonding will be next-gen bonding technology. Besi is also developing high-volume mainstream production systems.
Transfer molding started to show advantages in complex SiP packages and WLP. In more classical fields, such as trim and form, singulation and plating, there are new developments adding capabilities for next-gen packaging.