from the just-a-"small"-improvement dept.
TSMC has announced plans to build its first test chips for data center applications using its 7 nm fabrication technology. The chip will use compute cores from ARM, a Cache Coherent Interconnect for Accelerators (CCIX), and IP from Cadence (a DDR4 memory controller, PCIe 3.0/4.0 links). Given the presence of the CCIX bus and PCIe 4.0 interconnects, the chip will be used to show the benefits of TSMC's 7 nm process primarily for high-performance compute (HPC) applications. The IC will be taped out in early Q1 2018.
The 7 nm test chips from TSMC will be built mainly to demonstrate capabilities of the semiconductor manufacturing technology for performance-demanding applications and find out more about peculiarities of the process in general. The chip will be based on ARMv8.2 compute cores featuring DynamIQ, as well as a CMN-600 interconnect bus for heterogeneous multi-core CPUs. ARM and TSMC do not disclose which cores they are going to use for the device - the Cortex A55 and A75 are natural suspects, but that's speculation at this point. The new chip will also have a DDR4 memory controller as well as PCI Express 3.0/4.0 links, CCIX bus and peripheral IP buses developed by Cadence. The CCIX bus will be used to connect the chip to Xilinx's Virtex UltraScale+ FPGAs (made using a 16 nm manufacturing technology), so in addition to implementation of its cores using TSMC's 7 nm fabrication process, ARM will also be able to test Cadence's physical implementation of the CCIX bus for accelerators, which is important for future data center products.
At a special event last week, TSMC announced the first details about its 5 nm manufacturing technology that it plans to use sometime in 2020. CLN5 will be the company's second fabrication process to use extreme ultraviolet (EUV) lithography, which is going to enable TSMC to aggressively increase its transistor density versus prior generations. However, when it comes to performance and power improvements, the gains do not look very significant.
Just like other fabs, TSMC will gradually ramp up usage of ASML's Twinscan NXE:3400 EUV step and scan systems. Next year TSMC will start using EUV tools to pattern non-critical layers of chips made using its second-gen 7 nm fabrication technology (CLN7FF+). Usage of EUV for non-critical layers will bring a number of benefits to the CLN7FF+ vs. the original CLN7FF process, but the advantages will be limited: TSMC expects the CLN7FF+ to offer a 20% higher transistor density and a 10% lower power consumption at the same complexity and frequency when compared to the CLN7FF. TSMC's 5 nm (CLN5) technology will increase the usage of EUV tools and this will bring rather massive advantages when it comes to transistor density: TSMC is touting a 1.8x higher transistor density (~45% area reduction) when compared to the original CLN7FF, but it will only enable a 15% frequency gain (at the same complexity and power) or a 20% power reduction (at the same frequency and complexity). With the CLN5, TSMC will also offer an Extremely Low Threshold Voltage (ELTV) option that will enable its clients to increase frequencies of their chips by 25%, but the manufacturer has yet to describe the tech in greater detail.
1.8x higher transistor density and up to 15% frequency gain or 20% power reduction? You should be thankful you're getting anything!
GlobalFoundries has halted development of its "7nm" low power node, will fire 5% of its staff, and will also halt most development of smaller nodes (such as "5nm" and "3nm"):
GlobalFoundries on Monday announced an important strategy shift. The contract maker of semiconductors decided to cease development of bleeding edge manufacturing technologies and stop all work on its 7LP (7 nm) fabrication processes, which will not be used for any client. Instead, the company will focus on specialized process technologies for clients in emerging high-growth markets. These technologies will initially be based on the company's 14LPP/12LP platform and will include RF, embedded memory, and low power features. Because of the strategy shift, GF will cut 5% of its staff as well as renegotiate its WSA and IP-related deals with AMD and IBM. In a bid to understand more what is going on, we sat down with Gary Patton, CTO of GlobalFoundries.
[...] Along with the cancellation of the 7LP, GlobalFoundries essentially canned all pathfinding and research operations for 5 nm and 3 nm nodes. The company will continue to work with the IBM Research Alliance (in Albany, NY) until the end of this year, but GlobalFoundries is not sure it makes sense to invest in R&D for 'bleeding edge' nodes given that it does not plan to use them any time soon. The manufacturer will continue to cooperate with IMEC, which works on a broader set of technologies that will be useful for GF's upcoming specialized fabrication processes, but obviously it will refocus its priorities there as well (more on GF's future process technologies later in this article).
So, the key takeaway here is that while the 7LP platform was a bit behind TSMC's CLN7FF when it comes to HVM – and GlobalFoundries has never been first to market with leading edge bulk manufacturing technologies anyway – there were no issues with the fabrication process itself. Rather there were deeper economic reasons behind the decision.
GlobalFoundries would have needed to use deep ultraviolet (DUV) instead of extreme ultraviolet (EUV) lithography for its initial "7nm" chips. It would have also required billions of dollars of investment to succeed on the "7nm" node, only to make less "7nm" chips than its competitors. The change in plans will require further renegotiation of GlobalFoundries' and AMD's Wafer Supply Agreement (WSA).
Meanwhile, AMD will move most of its business over to TSMC, although it may consider using Samsung:
Last week, TSMC made two important announcements concerning its progress with extreme ultraviolet lithography (EUVL). First up, the company has successfully taped out its first customer chip using its second-generation 7 nm process technology, which incorporates limited EUVL usage. Secondly, TSMC disclosed plans to start risk production of 5 nm devices in April.
TSMC initiated high-volume manufacturing of chips using its first generation 7 nm fabrication process (CLN7FF, N7) in April. N7 is based around deep ultraviolet (DUV) lithography with ArF excimer lasers. By contrast, TSMC's second-generation 7 nm manufacturing technology (CLN7FF+, N7+) will use extreme ultraviolet lithography for four non-critical layers, mostly in a bid to speed up production and learn how to use ASML's Twinscan NXE step-and-scan systems for HVM. Factual information on the improvements from N7 to N7+ are rather limited: the new tech will offer a 20% higher transistor density (because of tighter metal pitch) and ~8% lower power consumption at the same complexity and frequency (between 6% and 12% to be more precise).
[...] After N7+ comes TSMC's first-generation 5 nm (CLN5FF, N5) process, which will use EUV on up to 14 layers. This will enable tangible improvements in terms of density, but will require TSMC to extensively use EUV equipment. When compared to TSMC's N7, N5 technology will enable TSMC's customers to shrink area of their designs by ~45% (i.e. transistor density of N5 is ~1.8x higher than that of N7), increase frequency by 15% (at the same complexity and power) or reduce power consumption by 20% power reduction[sic] (at the same frequency and complexity).
TSMC will be ready to start risk production of chips using its N5 tech in April, 2019. Keeping in mind that it typically takes foundries and their customers about a year to get from risk production to HVM, it seems like TSMC is on-track for mass production of 5 nm chips in Q2 2020, right in time to address smartphones due in the second half of 2020.
Tape-out. Risk production = early production.
Related: TSMC to Build 7nm Process Test Chips in Q1 2018
"3nm" Test Chip Taped Out by Imec and Cadence
TSMC Will Make AMD's "7nm" Epyc Server CPUs
GlobalFoundries Abandons "7nm LP" Node, TSMC and Samsung to Pick Up the Slack