Tag Archives: letter-dd-tech

By David Holden

Cars that can get along without drivers are coming, down the road, but they are a small part of the changes that the global transportation industries will undertake as microelectronics and the Internet of Things prompt major changes in infrastructure and logistics, as well as all type of vehicles.

Speakers at the opening session of “The Internet of Things: from sensors to zero power,” a LetiDays conference in Grenoble, France, shared their near-term forecasts for transport and the multiple opportunities that will stem from these changes.

Vincent Roger, transport business development manager at CEA-Leti explained that Leti-designed autonomous sensors allow monitoring of wear and tear on roads and train tracks, which enables their owners to predict when maintenance will be required. An emerging, potentially disruptive result of the IoT and sensors that monitor activity is a pay-per-use business model, in which owners pay manufacturers for the actual use of equipment rather than purchasing it.

 

Even automakers may move toward a service-based business model, and away from just car manufacturing, said Matt Hatton, director at Machina Research.

 

Presenters agreed that privacy concerns, based on devices tracking movement and activity of consumers, may be a barrier to rapid adoption of IoT applications. But Gilles Le Calvez of Valeo said that as they increasingly understand the benefits of connectivity, consumers will accept it more. He also showed a video of a driverless Valeo automated vehicle equipped with sensors and other microelectronics that is able locate and pull into open parking spaces.

 

Roger explained a new Leti “morpho” technology, using piezoelectric elements, that can be used for IoT applications that provide structural-health monitoring (SHM) for railways, bridges and pipes or cables buried or hidden inside tunnels.

 

Leti’s MEMS-based SHM systems enable real-time and remote monitoring, including tracking the infrastructure response to storms and other events, and the changes over time. These SHM systems include sensors networks, embedded signal processing and optimization of power consumption.

Several speakers emphasized the importance of controlling power consumption of the billions of devices that are projected to be connected to the IoT in the next decade. Leti CEO Laurent Malier said the power, performance and cost advantages of Fully Depleted Silicon-on-Insulator (FD-SOI) devices are well suited to power IoT applications because of the technology’s high-performance and low power consumption features. Leti and STMicroelectronics recently demonstrated an ultra-wide-voltage range (UWVR) digital signal processor (DSP) that provides up to 50 percent lower power consumption than competing technologies.

David Holden is Cooperative Programs Manager at CEA-Leti

By Shannon Davis, Web Editor

Overheard @The ConFab: “I feel the best I’ve felt about semi since 2009.” –Mike Noonen, Silicon Catalyst

Monday’s research and development panel discussion at The ConFab 2014 started on that optimistic note as Moderator Scott Jones of AlixPartners led a discussion on Optimizing R&D Collaboration. Panelists Chris Danely of JP Morgan, Lode Lauwers of imec, Rory McInerney of Intel and Mike Noonen of Silicon Catalyst discussed where the next big growth drivers will come from and the ability of the industry to continue scaling and remain on Moore’s Law through the introduction of new technologies such as EUV, Advanced Packaging and 450mm. The panel also touched on the role startups will play and how increased collaboration can benefit the industry.

Here are highlights from Monday’s discussion.

How do you feel about the semiconductor cycle – is that at a positive point for innovation and small, start-up companies?

Mike Noonen: I feel the best about I’ve felt about semi since 2009. Without a doubt. When you combine that situation that we’re in with a couple driving forces, all of that has fundamental benefits to the semiconductor business at large. You take those mega trends that are not leading edge applications with the challenge of Moore’s Law – those are developing a whole host of innovation. We think this is a great time to think about how to reinvigorate startups – this is the best time to think about innovation.

From left to right: Panelists Chris Danely of JP Morgan, Mike Noonen of Silicon Catalyst, Lode Lauwers of imec, and Rory McInerney of Intel

From left to right: Panelists Chris Danely of JP Morgan, Mike Noonen of Silicon Catalyst, Lode Lauwers of imec, and Rory McInerney of Intel

Consolidation is a big theme right now. Is this something that’s holding us back the industry?

Rory McInerney: I don’t think the industry is consolidating for us as much as we think. The big players are still HP, Lenovo, etc. The new players are Google, Facebook, Amazon, etc. – many didn’t exist 10 years ago. Within our world, there’s the traditional space, but there’s a ton of new stuff in the cloud and server segment.

Tell us some of the most exciting areas Intel is participating in.

Rory McInerney: On the data center side, we do want our 10 and 7nm, but one of the drivers of our business is the massive amount of data being generated around the world. There are tens of billions of devices that will be connected to the Internet in the few years. The only commonality in the [IoT] numbers is that they go up. All of them will have some element of connectivity and with that comes data. And that drives a virtual cycle. In our business, we love this – my point is, there’s a huge room for innovation. The innovation isn’t just the device but the software and application side.

How do investors view the emerging markets and trends? Do they see the opportunities or are they still focusing on traditional markets?

Chris Danely: From a broad perspective, the thing that an analyst looks at – are they playing to their strengths? You might have a company that starts out very successful, but they don’t play to their strengths and start to waste money. For example, Texas Instruments has taken their R&D down, but still outgrow the industry, because they play to their strengths. Another example is Intel – in the last 3 years, they were in the foundry business – we see a lot of potential to upset the apple cart in the foundry business. Nobody else could do this, but this is an area where we see them exploiting their strengths. Is the company playing to its strengths? We also look at ARM on servers – we don’t know if this is going to work or not, but I don’t think this changing the landscape of the industry. There’s still a bright future with semiconductor stocks.

How can executives communicate their R&D strategy better?

Chris Danely: I’ll use my personal experience – you want to keep that message very simple. Identify the growth trends. Make sure the message goes out continuously. Don’t be afraid to use a few buzz words/charts.

Lode Lauwers: If I may, Wall Street is looking in the short term. Time scale [for R&D] is close to 15 years. I don’t know if Wall Street has that visibility. I think a company should consider R&D as a long term investment. We go for long term engagements.

Rory McInerney: It’s a portfolio question in terms of R&D – you’re going to have your short term and your long term investments. I don’t think Wall Street is looking at all the details of investments. I think that our investments on the product side go out 10 years, but they’re small compared to our other investments.

Chris Danely: Wall Street has to consider about things on a six month basis.

Mike Noonen: Biotech, which has a very long time to market, is the second largest venture capital in the US. Biotech has remained lucrative and interesting in the US. In this area, companies go after a single application or problem, and it’s a vibrant and healthy investment. The take away is – it’s all about the economics. It might enable small start ups to innovate and then be acquired.

How should the industry leverage a company like imec?

Lode Lauwers: More than ever, you need to build partnerships. In this industry, we used to say, “Our company can work on its own.” Now, your ecosystem needs to become wider. Ten years ago, people were still sponsoring R&D. Now we are assessed in every individual area, deliverable by deliverable, on does it benefit, is there ROI. You need to be able to deliver relevant work. A company on its own doesn’t always have these abilities in house. Using imec, it’s like building on competences.

Do you see differences in how you approach partnerships?

Chris Danely: The CEOs and CFOs of semi companies are under pressure to not increase expenses, and that’s stifled risk-taking. Some are now approaching R&D through acquisition of startups with personnel – rather than partnerships.

Do you think these companies are larger – semi is a part of a much larger landscape – do you think this might drive the industry/change the landscape?

Rory McInerney: About 70-80 percent of cloud computing today is driven by the social media. That didn’t exist 5 years ago. There is a direct link between that and the changing semi landscape.

What is the biggest risk in the industry right now?

Chris Danely: Saturation. Semi companies are profitable, but we’re starting to see a lot of them, especially as fablite and fabless models are catching on.

Moderator Scott Jones of AlixPartners

Moderator Scott Jones of AlixPartners

When it comes to electronics, silicon may one day have to share the spotlight. In a paper recently published in Nature Communications, researchers from the USC Viterbi School of Engineering describe how they have overcome a major issue in carbon nanotube technology by developing a flexible, energy-efficient hybrid circuit combining carbon nanotube thin film transistors with other thin film transistors. This hybrid could take the place of silicon as the traditional transistor material used in electronic chips, since carbon nanotubes are more transparent, flexible, and can be processed at a lower cost.

Electrical engineering professor Dr. Chongwu Zhou and USC Viterbi graduate students Haitian Chen, Yu Cao, and Jialu Zhang developed this energy-efficient circuit by integrating carbon nanotube (CNT) thin film transistors (TFT) with thin film transistors comprised of indium, gallium and zinc oxide (IGZO).

“I came up with this concept in January 2013,” said Dr. Chongwu Zhou, professor in USC Viterbi’s Ming Hsieh Department of Electrical Engineering. “Before then, we were working hard to try to turn carbon nanotubes into n-type transistors and then one day, the idea came to me. Instead of working so hard to force nanotubes to do something that they are not good for, why don’t we just find another material which would be ideal for n-type transistors—in this case, IGZO—so we can achieve complementary circuits?”

Carbon nanotubes are so small that they can only be viewed through a scanning electron microscope. This hybridization of carbon nanotube thin films and IGZO thin films was achieved by combining their types, p-type and n-type, respectively, to create circuits that can operate complimentarily, reducing power loss and increasing efficiency. The inclusion of IGZO thin film transistors was necessary to provide power efficiency to increase battery life. If only carbon nanotubes had been used, then the circuits would not be power-efficient. By combining the two materials, their strengths have been joined and their weaknesses hidden.

Zhou likened the coupling of carbon nanotube TFTs and IGZO TFTs to the Chinese philosophy of yin and yang.

“It’s like a perfect marriage,” said Zhou. “We are very excited about this idea of hybrid integration and we believe there is a lot of potential for it.”

The potential applications for this kind of integrated circuitry are numerous, including Organic Light Emitting Diodes (OLEDs), digital circuits, radio frequency identification (RFID) tags, sensors, wearable electronics, and flash memory devices. Even heads-up displays on vehicle dashboards could soon be a reality.

The new technology also has major medical implications. Currently, memory used in computers and phones is made with silicon substrates, the surface on which memory chips are built. To obtain medical information from a patient such as heart rate or brainwave data, stiff electrode objects are placed on several fixed locations on the patient’s body. With this new hybridized circuit, however, electrodes could be placed all over the patient’s body with just a single large but flexible object.

With this development, Zhou and his team have circumvented the difficulty of creating n-type carbon nanotube TFTs and p-type IGZO TFTs by creating a hybrid integration of p-type carbon nanotube TFTs and n-type IGZO TFTs and demonstrating a large-scale integration of circuits. As a proof of concept, they achieved a scale ring oscillator consisting of over 1,000 transistors. Up to this point, all carbon nanotube-based transistors had a maximum number of 200 transistors.

“We believe this is a technological breakthrough, as no one has done this before,” said Haitian Chen, research assistant and electrical engineering PhD student at USC Viterbi. “This gives us further proof that we can make larger integrations so we can make more complicated circuits for computers and circuits.”

The next step for Zhou and his team will be to build more complicated circuits using a CNT and IGZO hybrid that achieves more complicated functions and computations, as well as to build circuits on flexible substrates.

“The possibilities are endless, as digital circuits can be used in any electronics,” Chen said. “One day we’ll be able to print these circuits as easily as newspapers.”

Zhou and Chen believe that carbon nanotube technology, including this new CNT-IGZO hybrid, could be commercialized in the next five to 10 years.

“I believe that this is just the beginning of creating hybrid integrated solutions,” said Zhou. “We will see a lot of interesting work coming up.”

Storing gas on a sorbent provides an innovative, yet simple and lasting solution.

BY KARL OLANDER, Ph.D. and ANTHONY AVILA, ATMI, Inc., an Entegris company, Billerica, MA

The period following the introduction of subatmospheric pressure gas storage and delivery was punctuated by continuous technical innovation.

Even as the methodology became the standard for supplying ion implant dopants, it continued to rapidly evolve and improve. This article reflects on the milestones of the last 20 years and considers where this technology goes from here.

From the beginning, the semiconductor industry’s concern over using highly toxic process gases was evident by the large investment being made in dedicated gas rooms, robust ventilation systems, scrubbers, gas containment protocols and toxic gas monitoring. While major advances have been made in the form of automated gas cabinets and valve manifold boxes, gas line components, improved cylinder valves and safety training, the underlying threat of a catastrophic gas release remained.

Risk factors targeted

The underlying risk with compressed gases is twofold: high pressure, which provides the motive force to discharge the contents of a cylinder, and secondly, a relatively large hazardous production material inventory, which can be released during a containment breach. Pressure also is a factor in component failure and gas reactivity, e.g., corrosion. Mitigating these issues would considerably increase safety.

FIGURE 1. The stages of developing a new chemical precursor for use in commercial IC production.

FIGURE 1. The stages of developing a new chemical precursor for use in commercial IC production.

Analysis of the risks suggested an on-demand, point-of-use gas generator would improve safety by both reducing operating pressure and gas inventory[1]. The challenges associated with this approach include complexity of operation and gas purity, especially in a fab or process tool setting. Chemical generation of arsine, while possible, per equation [A], also substituted a highly reactive toxic solid for arsine[2]. Considerable safety and environmental issues accompanied the operation of such a generator. An on-demand, point-of-use electrochemical approach for supplying arsine, per equation [B], would also eliminate the need for high pressure storage if the associated operational issues could be overcome. Numerous attempts at developing a commercial electrochemical generator just never proved successful[3].

[A] KAsH2 + H2O —> AsH3/H2O + KOH
[B] As(s) + 3H2O + 3e(-) —> AsH3(g) + 3OH(-)

Innovation from a simple(r) solution

Pressure swing adsorption processes utilize the selective affinity between gases and solid adsorbents, and are widely used to recover and purify a range of gases. Under optimal conditions, the gas adsorption process releases energy and produces a material that behaves mores like a solid than a gas.

Early work at reversibly adsorbing toxic materials on a highly porous substrate showed promise. In 1988, the Olin Corporation described an arsine storage and delivery system where the gas was [reversibly] adsorbed onto a zeolite, or microporous alumino- silicate, material[4]. A portion of the stored gas could be recovered by heating the storage vessel to develop sufficient arsine pressure to supply a process tool. In 1992, ATMI supplied a prototype system based on the Olin technology to the Naval Research Lab in Washington, D.C.

The breakthrough that lead to the first commercial subatmospheric pressure gas storage and delivery system occurred when ATMI reported the majority of the adsorbed gas could be supplied to the process by subjecting the storage vessel to a strong vacuum. Using vacuum rather than thermal energy simplified the process, providing the means for an on-demand system[5]. Using a sorbent had the effect of turning the gas into something more akin to a “solid.” That characteristic, coupled with the absence of a pressure driver, delivered an inherently safe condition. The vacuum delivery condition also helped define where the technology would find its first application: ion implantation[6].

Safe and efficient gas storage and delivery

In 1993, prototype arsine storage and delivery cylinders based on vacuum delivery were beta tested at AT&T in Allentown, PA[g] [f]. The system was trademarked Safe Delivery Source®, or SDS®. Papers were presented on safe storage and delivery of ion implant dopant gases the following year in Catania, Sicily at the International Ion Implant Technology Conference[7].

The goal to find a safer method to offset the use of compressed gases was realized: (1) gas is stored at low pressure (ca. 650 Torr at 21°C) and (2) the potential for large and rapid gas loss is averted. Leaks, if they occur, whether by accidental valve opening or a containment breach, would be first inward into the cylinder. Once the pressure equalizes, gas loss to the environment would be governed mainly by diffusion as the gas molecules remain associated with the sorbent. The SDS package, while not a gas generator per se, effectively functions like one.

FIGURE 2. Cutaway view of SDS3 carbon pucks within a finished cylinder.

FIGURE 2. Cutaway view of SDS3 carbon pucks within a finished cylinder.

While subatmospheric pressure operation is an artifact of having to “pull the gas” away from the sorbent, it has become synonymous with safe gas delivery. The optimization work which followed focused on reducing pressure drop in the gas delivery system by improving conductance in valves, mass flow controllers and delivery lines. A restrictive flow orifice was no longer required. The new gas sources proved to work best when in close proximity to the tool.

The years after this technology introduction also saw considerable efforts to improve the sorbent; ultra-pure carbon replaced the zeolite-based material used in the first generation SDS (SDS1), roughly doubling the deliverable quantities of gas per cylinder. These granular carbon sorbents in the SDS2 were later replaced by solid, round monolithic carbon “pucks” in SDS3 (FIGURE 2), which necessitated the cylinder be built around the sorbent[8]. This improvement again roughly doubled gas cylinder capacity.

Recognized in international standards

In 2012, the United Nations (U.N.) recognized the uniqueness of adsorbed gases and amended the Model Regulation for the Transport of Dangerous Goods by creating a new “condition of transport” for gases adsorbed on a solid and assigning a total of 17 new identification numbers and shipping names to the Dangerous Good List. Adoption is expected to occur by 2015. A few of the additions are noted here.

Arsine   – UN 2188 – compressed
Arsine, adsorbed – UN 3522 – SDS
Phosphine – UN 2199 – compressed
Phosphine, adsorbed – UN 3525 – SDS

FIGURE 3. The evolution of a SAGS Type 1 gas package.

FIGURE 3. The evolution of a SAGS Type 1 gas package.

In recent years, fire codes have been updated through the definition and classification of subatmospheric Gas Systems, or SAGS, based on the internal [storage] pressure of the gas.9 Systems based on both sub-atmospheric pressure storage and delivery are designated as Type 1 SAGS. It is important to note that the UN definition for adsorbed gases, and the resulting new classifications mentioned above, only applies to Type 1 SAGS, defined as follows:

3.3.28.5.1 Subatmospheric Gas Storage and Delivery System (Type 1 SAGS). A gas source package that stores and delivers gas at sub-atmospheric pressure and includes a container (e.g., gas cylinder and outlet valve) that stores and delivers gas at a pressure of less than 14.7 psia at NTP.

It is also worth mentioning that sub-atmospheric pressure gas delivery can also be achieved using high pressure cylinders by embedding a pressure reduction and control system. The Type 2 SAGS typically employs a normally closed, internal regulator[s] that a vacuum condition to open. This is not a definition of sub-atmospheric storage and delivery, but of sub-atmospheric delivery only.

3.3.28.5.2 Subatmospheric Gas Delivery System (Type 2 SAGS). A gas source package that stores compressed gas and delivers gas subatmospherically and includes a container (e.g., gas cylinder and outlet valve) that stores gas at a pressure greater than 14.7 psia at NTP and delivers gas at a pressure of less than 14.7 psia at NTP.

In general, Environmental Safety and Health managers, risk underwriters and authorities having jurisdiction recognize the importance of SAGS and requires recommend their use whenever process conditions allow[10].

Expanding SAGS into new applications

Taking the lessons learned from SDS2/SDS3 in ion implant operations, along with key findings from
other applications like HDP-CVD (the SAGE package) and combined with sorbent purification and carbon nanopore size tuning, SAGS Type 1 packages are poised to offer their safety advantages in new and emerging areas, as well as add even more safety and efficiency benefits. Currently, a new package called Plasma Delivery SourceTM (PDSTM) is available for high flow rate applications, while maintaining all the safety attributes of the SAGS Type 1 package.

Also, in addition to the inherent safety, PDS employs a pneumatic operator (valve) to the cylinder which further minimizes the opportunity for human error. In an emergency, such as a toxic gas alarm, pressure excursion, loss of exhaust, etc., gas flow at the source can be quickly stopped and the cylinder isolated. Cycle/purge operations are made safer as human involvement is minimized. Human-initiated events, like over-torqueing the valve, failing to close the valve or even back-filling a cylinder with purge gas, are prevented.

SDS1 SDS2 SDS3
Arsine 200 559 835
Phosphine 85 198 385

Expanding the use of SAGS beyond the domain of ion implant involves successfully navigating key process factors such as operating pressure, flow rates, proximity to the tool and purity. One approach includes coupling the PDS cylinder and gas cabinet together to yield a plug and play “smart” delivery system. Unlike high pressure systems, which are more concerned with excess flow situations, knowing and controlling pressure allows a SAGS cabinet to operate at a reduced risk. This enables linking cabinet ventilation rates with the system operating pressure. During normal operating conditions, the exhaust rate could be reduced by up to 80 percent because the system is operating sub-atmospherically. Should the operating pressure exceed a preset threshold, the exhaust flow would automatically revert to a higher range or the cylinder valve would close.

The future, therefore, could see these PDS packages extended to another level by incorporating them into smart delivery systems, which will further reduce risk, maximize efficiency, improve cost of ownership and expand the footprint for SAGS into new applications like plasma doping, solar, epitaxy and etch.

Summary

During the last 20 years, the semiconductor industry undertook a large effort to develop safer gas delivery technologies to reduce risks associated with dopants used in ion implant. Many technologies were considered, including chemical and electrochemical gas generators, complexing gases with ionic liquids or mechanically controlling cylinder discharge pressure using embedded regulator devices.

In the end, storing gas on a sorbent provided an innovative, yet simple and lasting solution. Gas-sorbent interactions are well understood, reproducible and can be achieved with a minimum of moving parts. Gas release risks, driven by pressure, are all but removed from consideration. And any potential for human error continues to be a target for improvement wherever toxic gases are used.

References

1. Proc. Natl. Acad. Sci. USA 89 pp 821-826, 1992.
2. Appl. Phys. Lett., 60 1483
3. Electron Transfer Technology, US Patent 59225232
4. Olin Corporation, US Patent US4744221A
5. Advanced Technology Materials, US Patent US5518528 6. Many thanks to Dan McKee and Lee Van Horn for being the first of many early adopters.
7. Proceedings of the Tenth International Conference on Ion Implantation Technology, 1994, pp 523-526.
8. DOT-SP 13220.
9. NFPA 318, Standard for the Protection of Semiconductor Fabrication Facilities 2012 Edition. 10. SAGS in the FAB, SST reference

ATMI is a wholly owned subsidiary of Entegris, Inc. ATMI, Safe Delivery Source, SDS, Plasma Delivery Source and PDS are trademarks of Entegris, Inc. in the U.S., other countries, or both. All other names are trademarks of their respective companies.