Advanced substrates for 3D and other new markets drive new fab inspection equipment – interview with Altatech GM

New approaches in chipmaking and fast-evolving specialty markets are driving the need for new equipment on the fab floor. 3D chips (be they stacked or bonded), MEMS, lighting, power – they’re all leveraging wafer substrates in new ways. Altatech, the equipment division of SOI-wafer leader Soitec, has just announced new inspection equipment for foundry and IDM customers fabbing 3D and other chips. ASN talks to Jean-Luc Delcarri, Altatech general manager, about the company and its recent announcements.

Advanced Substrate News (ASN): Can you tell us briefly about the company and the markets it serves?

mgmt_jldelcarri
Jean-Luc Delcarri, Altatech general manager

Jean-Luc Delcarri (JLD): Altatech makes specialty equipment for the fab floor. We have two main areas of deep expertise: one is in defect inspection, and the other is in CVD* technologies for semiconductor, LEDs, MEMS and photovoltaic devices. I founded the company in 2004, and then in 2012 we became a subsidiary of SOI wafer leader, Soitec.

ASN: At Semicon Europa 2015, you announced “…a new, high-speed inspection system for ultra-thin, transparent and bonded substrates inspection for 3D applications in power, MEMS and mobile technologies.” What’s driving that market?

JLP: Yes, at Semicon we announced the Eclipse TS, which is a unique, high-reliability and easy-to-implement inspection system solution that’s now ready for mass production.

You’ve got the need for these advanced substrates that’s being driven by really rapidly growing markets in automotive, industrial power and mobile electronics. We’ve been working quietly on this tool for years, and now the Eclipse TS has been qualified for volume manufacturing at a leading-edge semiconductor manufacturer, so we’re really excited about it.

AltatechEclipseTSInspectionSystem2015
Altatech’s Eclipse TS, a high-speed inspection system for ultra-thin substrates in 3D applications.

ASN: What makes the Eclipse TS different from other inspection sytems?

JLP: When you’re looking for defects on these advanced wafer solutions, you have to do much more than scan the top: you need to inspect the front side, the back side and the edge of very thin wafers – and you have to do it without touching them. Our ability to do all this makes us totally unique on the market: we have built this tool on a strong IP portfolio.

So with the Eclipse TS, you have a high-speed inspection system that can measure very thin and stacked wafers down to 50 microns, as well as Taiko rings, stacked substrates and silicon-on-glass wafers. Plus we can do the front-side, back-side and edge inspection in one pass with no back-side contact.

In today’s 3D technologies, substrates undergo grinding, stacking and gluing, so you can end up with wafers with a very high bow, or  wafers with a warp of up to 6 mm. We can handle those wafers. In fact, the Eclipse system can monitor these sorts of processes. The inspection occurs without any contact on the active surface, and at a throughout of more than 90 wafers per hour for 300-mm substrates.

We’re of course compliant with the latest automation standards, so the system can be fully integrated into the line, and provide comprehensive reporting for defects classification and yield maps.

Our full Altatech Eclipse series covers advanced metrology and holistic inspection systems. That means we can detect, count and bin defects during the wafer manufacturing process as well as do continuous outgoing wafer-quality inspection. So the quality of both the wafer-surface and edge is ensured. We also have proprietary Eclipse sub-modules that detect specific sorts of particles and defects of interest for both patterned or unpatterned wafers.

All that puts Altatech in a leading position in what is a very large market opportunity.

AltatechAltaCVD3DMemoryCell2015
Altatech’s AltaCVD 3D Memory Cell deposits the ultra-thin semiconductor films used in high-density, low-power memory chips 10 times faster than conventional ALD systems.

ASN: You also make CVD – deposition – equipment. Can you tell us a little about that, and what’s driving those markets?

JLP: Sure. Last year we introduced the AltaCVD 3D Memory Cell™, which is the newest member of our AltaCVD product line. This is used for depositing ultra-thin semiconductor films when you’re manufacturing the high-density, low-power memory chips used throughout mobile electronics. Our new system does atomic-layer deposition 10 times faster than conventional ALD** systems, which is of course huge when you’re manufacturing advanced memories where you need to run in very high-volume production with extreme cost efficiency.

In the new 3D device architectures for mobile apps, our customers are looking to really increase memory capacity and boost performance. And to do this, they need very advanced material deposition to create atomic-layer films with high uniformity – you really are at the atomic level of control here. The AltaCVD 3D Memory Cell deposits layers of chalcogenide*** materials by using a combination of precursors, which is very leading edge.

So with our tool you can use conventional gaseous or solid precursors, but we also have a patented pulsed technology, which means you can also use advanced CVD precursors that are available only in liquid form. This is remarkable versatility: it allows us to achieve exceptional step coverage over features with very high aspect ratios – that’s a key performance requirement when you’re talking about vertical integration high-density memory circuits.

You can also use it for advanced pre-treatment of semiconductor surfaces (which improves circuit functionality), as well as post-treatment of surfaces (which enhances electrical performance).

Because it’s used in everything from research to high-volume manufacturing, it can process 200-mm or 300-mm substrates, and uses a single-wafer, multi-chamber architecture. One of our key customers demonstrated it last year. We’re now selling production units, and we’re pleased to say it’s been very successful.

ASN: Do you have other products in the pipeline?

JLP: Next up we have a new solution for high aspect ratio 3D copper deposition. The system, which is called RUBY, can deposit a barrier layer of titanium nitride or tantalum nitride with almost 100% step coverage on an aspect ratio higher than 10:1. This is followed by deposition of a copper seed layer with similar performance. Combined with a proprietary copper cleaning process, it will be able to meet the growing challenge of copper metallization in MEMS and semiconductor 3D integration. We’ll release it as soon as we’ve completed our product milestones for reliability and performance.

ASN: Where do you see the highest-growth areas?

JLP: We’ve developed the right technology for the right time in a number of key markets, so we’re really well-positioned to answer the needs of a number of high-growth markets. The move to 450mm wafers is something we’re ready for, which will probably happen first in advanced memories. But in the meantime we also see significant activity in MEMS, RF, high power and LEDs. We’re winning customers in China who are looking to be leaders in these markets. All in all, much of the future of the phone in your pocket depends on what we can help our customers do in high-volume and cost-effectively on the fab floor – so it’s a very exciting time to be in this business.

~ ~ ~

*CVD=chemical vapor deposition

**ALD=atomic layer deposition

*** chalcogenides include sulphides, selenides, and tellurides

Leave a Reply

Your email address will not be published. Required fields are marked *