Globalfoundries’ CEO on why FD-SOI and why now
Globalfoundries has developed a 22nm FD-SOI platform of four processes based on a licensing deal it originally signed with STMicroelectronics back in 2012 (see Globalfoundries launches own FD-SOI processes). That was before Sanjay Jha arrived at the company to take over as CEO at the beginning of 2014. Jha had previously been CEO of Motorola Mobility Inc. – now part of Google – and COO at Qualcomm.
The original plan was for Globalfoundries to act as a licensed foundry supplier of a 28nm FD-SOI process developed by STMicroelectronics. Samsung has agreed to take on that role while Globalfoundries has been putting in its own engineering expertise to produce four process variants at a 22nm node that are tuned to applications behind the leading-edge catered to by 14nm FinFET processes.
Jha explained to eeNews Europe, why Globalfoundries is embracing FDSOI and why now.
"Beyond 28nm Moore’s Law faced challenges and industry faced a choice; FinFET or FD-SOI. We have 14nm FinFET in our wafer fab in the United States. Through our acquisition of IBM Microelectronics we are going to have access to 7nm," Jha said. "FinFET is very good for high cost, high volume, high performance applications. But there are many applications in IoT and mobile which require much lower power consumption."
So why didn’t Globalfoundries come earlier with a 28nm FD-SOI offering?
"The 22nm process overcomes some challenges at 28nm. The transistor is better and the 20 percent area scaling we get makes up for the cost of the substrate," Jha said. "That means we can offer better performance at the same cost as 28nm [alternatives to FD-SOI]," Jha added.
The higher cost of SOI wafer compared with a silicon wafer is one of the reasons often given as to why Intel and Taiwan Semiconductor Manufacturing Co. Ltd. (TSMC) rejected FD-SOI approach and single-minded pursued the FinFET.
Next: Dynamic control of transistors
In addition, Globalfoundries has made use of the possibility allowed in FD-SOI of back biasing to change transistor threshold voltages and performance characteristics and even make this into something customers can use dynamically. This is not something that can be easily done with the FinFET structure.
The second reason Jha gives is that markets and customer demand have been changing. "Three years ago 28nm was the leading-edge process. Back then we didn’t see market demand for 28nm FD-SOI. We do see demand now we have scaled the process and the market has moved on," said Jha
Jha pointed out that applications in entry and mid-tier mobile phones don’t need the highest performance but are still highly sensitive to power efficiency. Similarly many IoT applications require very little raw processing power but need power consumption to be reduced dramatically. "The market has developed for ultralow power. For example, the smartwatch typically needs recharging every day. We think we can increase battery life of smart watches by a factor of four using our technology," said Jha.
It’s also a European thing
The 22nm FD-SOI processes will be run at Globalfoundries’ wafer fab in Dresden, Germany where the launch announcement was made.
Globalfoundries Fab 1 in Dresden, Germany, The leading chip manufacturing facility in Europe. Source: Globalfoundries.
Jha said that Globalfoundries had received some support from the State of Saxony and was in "consultation" with the Germany government about the technology, but said it wasn’t the case that the Europe Union was paying incentives for Globalfoundries to adopt the FD-SOI process and place it in Europe.
Next: European relevance
Rutger Wijburg, senior vice president and general manager of the Dresden fab, acknowledged that Globalfoundries is taking part in European Commission administered projects such as Horizon 2020. "We plan to extend that activity," Wijburg said.
Manufacturing capacity at Dresden stands at about 600,000 to 700,000 wafer starts per year. "We want to get that to one million wafers per year," Jha said. Wijburg made it clear that FD-SOI and the Internet of Things are key to maintaining the relevance of the wafer fab in Dresden and its potential to energize semiconductor and electronics activity in Europe.
"Dresden was focused on the PC. Now we want to focus on technology relevant to industries in Europe. We need innovation to keep ahead and technology to revitalize German and European industries. We believe there is a lot of common ground between Globalfoundries, Infineon, NXP and STMicroelectronics," Wijburg said.
While FD-SOI might be characterized as being good for More-than-Moore applications while FinFET process address the leading edge of Moore’s Law Jha made it clear that More-than-Moore should now be considered the mainstream rather than a niche. "The mass market is at 28nm/22nm. Really it is leading-edge pure digital that is the niche," said Jha.
Instead the high-cost leading edge processes are really niche processes optimized for applications in data centers or on for high computational loads, albeit niches with volumes of hundred of millions of units per year. And it is true that the markets for past drivers of semiconductors – the PC and smartphone have flattened off. The next wave will be IoT Jha and Wijburg said.
Globalfoundries has a roadmap to take its FD-SOI platform to smaller geometries but Jha declined to discuss it. "There is a roadmap because there will be more computing in connected devices but there is a sweet spot where we are that we are excited about."
Similarly, Jha declined to discuss customer names or numbers that Globalfoundries might have already signed up to use its 22nm 22FDX platform. As design kits are only just becoming available it will be about 18 months before customers starting today can expect commercial silicon. "We are very comfortable with the traction we’ve got," said Jha.
Related links and articles:
News articles:
Globalfoundries launches own FD-SOI processes
GlobalFoundries Appoints Sanjay Jha CEO
GlobalFoundries’ FD-SOI revolution
Freescale, Cisco, Ciena Give Nod to FD-SOI
Samsung’s fabs to back adoption of ST’s 28nm FD-SOI
Globalfoundries commits to FDSOI process
ST opens up 28-nm, 20-nm FDSOI with GlobalFoundries