FOWLP is the fastest growing packaging platform and has been adopted for various applications from mobile to automotive to medical for packaging, for both low-end (e.g. audio codecs) and high-end devices (e.g. APU). However, cost is still a concern compared to other more mature packaging platforms. End customers are always pushing for lower cost.
One of the ways to reduce cost is to adapt the process of the fan-out package from wafer to large panel level. This brings economies of scale and higher carrier usage ratio which results in higher manufacturing efficiency and overall lower cost per package. So, Fan-out Panel Level Packaging (FOPLP) is currently attracting huge interest in the industry and is attracting players with many different business models, including outsourced semiconductor assembly and test (OSAT), integrated device manufacturers (IDMs), foundries, substrate manufacturers and FPD players. They sense an opportunity to enter the advanced packaging business via fan-out technology. After years of development/qualification/sampling, FOPLP is finally moving into volume production with 3 players, viz. Powertech Technology, NEPES and Samsung Electro-Mechanics, entering this market. The FOPLP market is expected to reach ~ US$280 million in 2023 at 79% CAGR 2018-2023, according to the Status of Panel Level Packaging 2018 report from Yole Développement.
(Source: Status of Panel Level Packaging 2018 – Yole Développement, April 2018)
Different equipment and material suppliers are involved in the FOPLP business, and Evatec is one of the key players that supply panel level sputter tools (PVD) for RDL fabrication, the key step for FOPLP processing. Evatec PVD tools for FOPLP are qualified at various customers for volume production and can handle a substrate size up to 600x 600mm.
Yole Développement (Yole) invited Evatec to discuss its activities, and to present its vision of the advanced packaging industry. Santosh Kumar, Senior Technology & Market Analyst from Yole, and Albert Koller, Head of Advanced Packaging Business Unit at Evatec, debated the technology evolution and the industry demand.
Evatec has also been invited by the Semiconductor & Software Team of Yole Développement to showcase its expertise and knowledge of the industry at the Advanced Packaging & System Integration Symposium powered by Yole Développement and NCAP. The Symposium takes place in Wuxi, China, on June 20 &21.
The detailed program is now available: Agenda.
Santosh Kumar: Evatec is one of the key equipment suppliers for FOPLP. Can you introduce the Evatec product line, its history and current activity?
Albert Koller: While talking with customers of our WLP solutions back in 2015 we recognized the market potential for a panel processing solution provided the processing yield and cost targets could be met. However, with the lack of standards available at that time, we also recognized that we needed to develop a hardware and process technology approach which could be flexible. We developed our FOPLP tool for the market in 2016 based on single panel processing of panels up to 550x550mm in a cluster architecture at throughputs of >20 panels per hour. The tool has already shown best in class performance in terms of adhesion, film specifications and process flexibility. This year we will introduce a platform that can even handle substrates up to 600x 600mm, or 4 times 300x300mm.
SK: What are the competitive advantages of your product lines for the panel packaging area?
AK: Process yields are critical to making FOPLP an attractive manufacturing approach. On one hand that means safe, secure, accurate handling of thin panels through the system, remembering that they often have high warpage. On the other hand, it also means “static processing” during individual process steps themselves, so that panels are secure and processes like panel cooling are most effective. Particle generation must also be minimized, another key control requirement for maintaining high panel processing yield.
SK: What are the technical challenges for PVD for RDL fabrication for panels? And how does the Evatec tool address these challenges?
AK: Apart from the panel handling challenges already discussed, challenges in FOPLP arise, just as in FOWLP, from the outgassing of substrates, the need to achieve good adhesion and of course the fact that metallization has to be uniform over much larger substrate sizes. At the end the contacts need to achieve very low Rc values and be consistent from panel to panel. Overall temperature control throughout all process steps is key for excellent performance and process stability.
Panel outgassing has been addressed successfully by simply scaling up the proven atmospheric batch degasser technology used in our FOWLP production systems with advantages of high temperature uniformity, high throughput, and the elimination of cross contamination relative to vacuum degas technology. For panel etch we combined Capacitively Coupled Etch Source technology and “Arctic Cooling”, another proven Evatec technology already used for FOWLP. For metallization itself, “rotating target technology” combined with “moving magnet technology” allowed us to achieve the deposition uniformities we needed. Most importantly, this is in static deposition mode without the need for any panel movement to reduce risk of particles.
SK: How do you see the evolution of the FOPLP market? What are the key roadblocks you see for its wider adoption?
AK: Currently I see the technical hurdles as less critical but, as in so many cases, it will be the cost.
SK: One of the key obstacles for equipment suppliers is the lack of standardization of panel size in the industry. Each company has their own panel size and process. How do you deal with such a challenge?
AK: We have actively chosen process technologies which lend themselves to simple scaling to accommodate whatever industry standards are adopted. This means we can eliminate customer risk – early adopters now don’t need to worry about our capability to handle different panel sizes later or the need to adopt new process technologies if their panel size gets bigger. In the end of course, it is important that we agree on a standard panel size in order to help system suppliers achieve economies of not having to manufacture multiple standards, and ultimately providing the lowest CoO for end users.
SK: In the industry, there is some skepticism about panel level fan-out packaging feasibility from the economic point of view. Most players believe the industry is still not ready for panel level fan-out as there is insufficient market to keep the lines busy. What is your opinion on this?
AK: Of course the industry is still in a very early phase and it will take several years before the path is clear but I am convinced that panel level packaging will have a place.
SK: In your opinion, what promising applications and markets can change the industry landscape and the positions of the leading equipment manufacturers in the panel packaging area?
AK: For a system supplier like us, FO panel level processing is not the only emerging topic, and the relentless trend for both increasing miniaturization and increased functionality in electronics will call for new approaches in the processing of general IC substrates. PVD techniques could step in where wet processing techniques are approaching their limits.
SK: Some of the tool suppliers for FOPLP leverage their experience from the FPD/PCB/Solar industries. Do you also leverage experience from other industries to design and develop tools for FOPLP?
AK: Handling thin bowed substrates was already a core competence with our CLUSTERLINE team. However, our FOPLP tool development team could also draw on their own experience from handling and processing of larger panel sizes in Solar and Large Area Display, such as the Capacitively Coupled Source Technology we use for etch. It was important for us to adopt production proven handling and process technologies for all steps in order to eliminate customer risk by providing the most reliable production hardware with the best production uptime and easiest system maintenance.
Albert Koller has more than 25 years experience in the semiconductor equipment industry. He held different management positions in development, marketing & sales and general management at both Unaxis and Oerlikon where he was responsible for Semiconductors at Oerlikon Systems for 9 years prior to the acquisition of the business by Evatec AG in 2015. With Evatec he was Business Unit Head of Cluster Systems and since April 2018 leads all activities in Advanced Packaging.
Santosh Kumar is currently working as Senior Technology & Market Research Analyst, in the Semiconductor & Software division at Yole Développement (Yole). He is involved in the market, technology and strategic analysis of the microelectronic assembly and packaging technologies. His main interest areas are advanced IC packaging technology including equipment & materials. He is the author of several reports on fan-out / fan-in WLP, flip chip, and 3D/2.5D packaging.
He received the bachelor and master degree in engineering from the Indian Institute of Technology (IIT), Roorkee and University of Seoul respectively. He has published more than 40 papers in peer reviewed journals and has obtained 2 patents. He has presented and given talks at numerous conferences and technical symposiums related to advanced microelectronics packaging.
Panel level packaging players are ready for high volume production – Get more
Related Reports and Monitors
RF Front-End Module Comparison 2021 – Volume 4 – Focus on WiFi 6/6E
Reverse Costing - Structural, Process & Cost Report
RF Front-End Module Comparison 2021 – Volume 3 – Focus on Samsung
Reverse Costing - Structural, Process & Cost Report