IEDM 2019 – Applied Materials panel EUV Recap

On Tuesday night of IEDM, Applied Materials held a panel discussion “The Future of Logic: EUV is Here, Now What?”. The panelists were: Regina Freed, managing director at Applied Materials as the moderator, Geoffrey Yeap, senior director of advanced technology at TSMC, Bala Haran, director of silicon process research at IBM, Ramune Nagisetty, senior principle engineer at Intel, Barbara De Salvo, silicon technology strategist at Facebook and Ali Keshavarzi, adjunct professor at Stamford University.

Each panelist presented their personal view on the topics discussed; theirs views do not represent the companies they work for. Furthermore, my typing skills are not good enough to get a verbatim transcript, the following is my summary/paraphrasing of what was discussed.

The panel began with each panelist presenting some key issues from their view:

Geoffrey Yeap

• System on Integrated Chips (SoIC) new TSMC process.
• Power Performance Area Cost Time – PPACT where new technologies need to be on-time.
• Need more low-VDD operation focus.
• Need a more energy efficient transistor.
• Houston, we do have a problem, interconnect resistance is a problem.

Ramune Nagisetty

Moore’s law four phases:

1. Denard scaling, dimensions drove performance.
2. Post Denard strained silicon, HKMG, FinFET.
3. DTCO (Design Technology Co-Optimization).
4. Heterogeneous Integration – Chip-lets infrastructure and ability to mix and match technologies.

Bala Haran

The future of logic:

• New architectures, nanosheets – more flexibility for design with Weff tunability, Epi defined channel not patterning, easier to scale. Dual Damascene Cu -> subtractive etch and alternative conductors.
• Orthogonal elements – scaling, eMemory.
• New materials and processes – for nanosheets you need volume-less work function using dipoles, integrated low temperature cleans, new materials.
• System Technology Co-Optimization.

Ali Keshavarzi

• Not all about scaling:
  • Moore’s law has slowed down.
  • Denard scaling is finished.
  • Von Neumann architecture of out of steam.
  • We need the next switch.
  • Communication energy has not scaled.
  • We need edge computing.
• Todays approach:
  • Communication centric, device to cloud and back to act.
  • Will be too much energy, too much latency and too much data.
  • Lack of privacy and security.
• Solution:
  • Edge computing before transmitting to the cloud.
  • Compute and act locally and then only transmit valuable data.
• Three keys:
  • Small-system AI locally.
  • Intermittent computing – instant, eNVM + arch + software.
  • Burst communication that is context aware.

Barbara De Salvo

• FinFET, 7nm, 5nm, 3nm, GAA, Vertical GAA, 2D Materials, etc.
• What will the next application be?
• Showed first “personal computer” and current smart phone.
• Not so distant future – augmented reality glasses – can see reality but also project enhancements, see in low light, see people from remote locations.
• Requirements:
  • Optics and display.
  • Computer vision.
  • System design.
  • User experience.
• Extremely difficult.
• Objectives for AR silicon:
  • 100x current performance/power.
  • Form factor – size of glasses.
  • Wireless – always connected.

Following the individual presentations, the panel discussion began with Regina Freed asking questions and then various panelists providing comments.

Regina Freed – what do we need to scale?

• Geoffrey Yeap – EUV opened the door, 5nm less masks for first time but interconnect resistance is an issue.
• Ramune Nagisetty – parasitics are an issue.
• Bala Haran – materials for reliability and route-ability.

Regina Freed – what do we need to enable this?

• Ramune Nagisetty – GAA, with all the papers we don’t have it yet, but it is a better transistor. Monolithic 3D and advanced packaging to put together heterogeneous technologies.

Regina Freed – what do we need for materials?

• Bala Haran – Epitaxy will be the new multi-patterning and area selective deposition, atomic layer etching.

Regina Freed – are we going to use more materials?

• Bala Haran? – Take out radioactives and noble gases and there are about 67 elements and we use about half of them. Over next decade we will use 50% of the ones that are left.

Regina Freed – do we need something else for interconnect?

• Geoffrey Yeap – we need a super conducting contact at room temperature.

Regina Freed – what do you think of buried power rail?

• Bala Haran – thinks it is a great concept, IBM had eDRAM with buried metals and there were a lot of challenges, BPR looks a lot like that.
• Ramune Nagisetty – thinks we will get there, power delivery is increasingly challenging, we will need it.

Regina Freed – AR/VR needs something very new, low power, small form factors, see through materials, what is needed from IC design?

• Barbara De Salvo – what do we really mean for PPA for 5nm, 3nm. Designer requirements are really different, high performance devices are always active, many users on same server so always used. In AR/VR long stand by, leakage is very important. Most of Moore’s law is for high performance, they need some way to customize the core technology. There are a lot of different markets and they need differentiation.

? to Geoffrey Yeap – a lot of your spending is driven by your customers.

• Geoffrey Yeap – we will pick a platform approach and then will customize for application around core platform for cost and yield. 5nm platform will serve 5G and server and then will customize.
• Barbara De Salvo – they want very low power and it is data transfer and memory access that is most costly. Several factors of difference between computing power and data movement. The core technology needs embedded memory. Memory developed for markets so far have not been at leading edge.
• Ali Keshavarzi – develop RRAM that is 1,000x or 10,000x better for memory in compute or AI? Micro drone has to be smart and low power and make decisions on board. Need to change the memory hierarchy, some of the learning to SRAM and some to eNVM.

Regina Freed to Bala Haran – what is needed?

• Bala Haran – High performance – low power is being touted for FDSOI with eMRAM for some applications and FinFET and then nanosheets for high performance and the requirements for these two are very different.
• Ramune Nagisetty – it’s such a different optimization point, look back to the iPhone that drove the technologies at foundries. There really needs to be a big customer that drives things like Apple.
• Geoffrey Yeap – there needs to be a big business pull to drive it.
• Ali Keshavarzi – what are you willing to pay and business case.
• Bala Haran – eMRAM for automotive is responding to the marketplace in the legacy nodes.
• Barbara De Salvo – for many years there was criticism of NAND Flash by NOR for reliability. Some companies never invested in the technology. When the application occurred, NAND took over. The technology needs to be ready for the application.
• Ali Keshavarzi – one argument in the past for embedded memory to only be on legacy nodes was for material compatibility. Lots of work at the conference on HfOx fero memory that is FinFET compatible. Maybe Facebook and TSMC should work on it and both be happy.
• Geoffrey Yeap – slightly different view, in the past 50 years business model has become the foundry model. TSMC service is king, they listen to customer and do what they need. In the right time the right technology will be there.
• Ali Keshavarzi – someone had to provide the leadership.
• Barbara De Salvo – for the innovation the core of software is very important, and it is addressed by the current model. To address the system, you need design and software.
• Ramune Nagisetty – we have an example when Alex net won the image-net competition, dataset, GPUs and algorithms. 1990s MIT researchers had backpack computers and glasses. There will be some confluence that will bring this all together. There are technologies that will meet the needs of AR/VR are in the pipeline.
• Ali Keshavarzi – you need to worry about performance per watt or it will go away.
• Ramune Nagisetty – it won’t go away; it will be there until it is met.
• Bala Haran – before we talk about anything else let’s talk about memory because most of the die is memory and GPU. Intel has a nice paper on L4, we need to look at double stacked MTJ, need to look at L3.
• Regina Freed – are you saying the future of logic is memory
• Bala Haran – the requirements for AI memory are different, you can live with more errors and that will drive down power. Nonvolatile for in-memory compute and analog elements for neuromorphic computing with 1,000x improvement.
• Barbara De Salvo – agrees for performance and edge devices but right now data transport is the issue.

Bala Haran asked Ramune Nagisetty – how do you see packaging?

• Ramune Nagisetty – take novel parts and memory and put them together in packages. You can take HBM and put it near the processor and it is the first toehold in the space. Packaging enables some novel memories even if they’re ready now but can’t be integrated with CMOS, they can be integrated by packaging, so it enables and accelerates.

Bala Haran asked Geoffrey Yeap – how do you manage legacy and leading edge?

• Geoffrey Yeap – turned it around and said let the market decide. Provide leading edge and legacy and chip-let and packaging technology and let the customers decide how to use the tools. At large volume the market will force cheaper. He remembers when SRAM was a separate chip until the market decided it should be on the logic chip.
• Ali Keshavarzi – we all understand the market, bring the chips closer with chiplet but it isn’t a monolithic solution on the die. Going chip to chip there is a power penalty.
• Ramune Nagisetty – in a 3D stack energy can be much less.
• Ali Keshavarzi – if you really want to map it in SRAM you need a complete wafer that is SRAM. We need to be very clever and with the business forces.

Regina Freed – We all talked about heterogeneous integration, what do we need to do to make it almost as good as on die?

• Ramune Nagisetty – tiling tax, power and interconnect penalties for going die to die. 3D and then layer transfer further reduce the tiling tax. Business model where you get the best in class die from TSMC, GF, Intel and integrate and integrate it and there is a failure who owns the problem. A lot of problems that are partly business and partly technology. We already have a model with the PCB industry with parts from all over the world and everyone gets paid. Heterogeneous with chip-lets where it comes together and looks like Legos.
• Barbara De Salvo – what about design tools for this.
• Ramune Nagisetty – yes there needs to be tools, flows and methods.

Regina Freed asked Geoffrey Yeap – are you thinking about enabling this?

• Geoffrey Yeap – if the customer asks for it.
• Bala Haran – one thing I would add on is a consolidation of OSATs or suppliers and it hasn’t happened in the packaging world. Too many options, panels, 2.5D, etc.
• Ali Keshavarzi – can you put the chips in a mold, RDL, extremely inexpensive.
• Ramune Nagisetty – the low-cost run is often related to volume, even something that seems inexpensive is expensive if you don’t have volume.

Regina Freed – can we trade off cost for performance to get to market?

• Ramune Nagisetty – cost is definitely important, being efficient, cost per function efficacy.
• Ali Keshavarzi – we have covered this.

Regina Freed – Last question before going to audience, until recently our model was serial with true collaboration with end user, do we need more collaboration?

• Ramune Nagisetty – we have had consortia in the past, not everyone is working in serial. She thinks the most interesting thing today is the cloud service providers creating their own chips.
• Barbara De Salvo – software – hardware optimization and customization of technology. Even in R&D it needs to be a view to the whole system. New players like Facebook, thinks it will be different in the future.
• Bala Haran – look at DRAM and Flash, deep collaboration between companies, thinks logic needs to have companies specialize in each piece.
• ? – We are all asking a lot of things from the industry but a lot is possible. New materials and processes and advanced packaging. Evolution is here and a combination of advanced technologies.