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Posts Tagged ‘Sensor’

79 GHz CMOS RADAR Chips for Cars from Imec and Infineon

Tuesday, May 24th, 2016

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By Ed Korczynski, Sr. Technical Editor

As unveiled at the annual Imec Technology Forum in Brussels (itf2016.be), Infineon Technologies AG (infineon.com) and imec (imec.be) are working on highly integrated CMOS-based 79 GHz sensor chips for automotive radar applications. Imec provides expertise in high-frequency system, circuit, and antenna design for radar applications, complementing Infineon’s knowledge from the many learnings that go along with holding the world’s top market share in commercial radar sensor chips. Infineon and imec expect functional CMOS sensor chip samples in the third quarter of 2016. A complete radar system demonstrator is scheduled for the beginning of 2017.

Whether or not fully automated cars and trucks will be traveling on roads soon, today’s drivers want more sensors to be able to safely avoid accidents in conditions of limited visibility. Typically, there are up to three radar systems in today’s vehicle equipped with driver assistance functions. In a future with fully automated cars, up to ten radar systems and ten more sensor systems using cameras or lidar (https://en.wikipedia.org/wiki/Lidar) could be needed. Short-range radar (SRR) would look for side objects, medium-range radar (MRR) would scan widely for objects up to 50m in front and in back, and long-range radar (LRR) would focus up to 250m in front and in back for high-speed collision avoidance.

“Infineon enables the radar-based safety cocoon of the partly and fully automated car,” said Ralf Bornefeld, Vice President & General Manager, Sense & Control, Infineon Technologies AG. “In the future, we will manufacture radar sensor chips as a single-chip solution in a classic CMOS process for applications like automated parking. Infineon will continue to set industry standards in radar technology and quality.”

The Figure shows the evolution of radar technology over the last decades, leading to the current miniaturization using solid-state silicon CMOS. Key to the successful development of this 79 GHz demonstrator was choosing to use 28 nm CMOS technology. Imec has been refining this technology as shown at ISSCC (isscc.org) for many years, first showing a 28nm transmitter chip in 2013, then showing a 28nm transmit and receive (a.k.a. “transceiver”) chip in 2014, and finally showing a single-chip with a transceiver and analog-digital converters (ADC) and phase-lock loops (PLL) and digital components in 2015. Long-term supply of eventual commercial chips should be ensured by using 28nm technology, which is known as a “long lived” node.

“We are excited to work with Infineon as a valuable partner in our R&D program on advanced CMOS-based 77 GHz and 79 GHz radar technology,” stated Wim Van Thillo, program director perceptive systems at imec. “Compared to the mainstream 24 GHz band, the 77 GHz and 79 GHz bands enable a finer range, Doppler and angular resolution. With these advantages, we aim to realize radar prototypes with integrated multiple-input, multiple-output (MIMO) antennas that not only detect large objects, but also pedestrians and bikers and thus contribute to a safer environment for all.”

Since the aesthetics are always important for buyers, automobile companies have been challenged to integrate all of the desired sensors into vehicles in an invisible manner. “The designers hate what they call the ‘warts’ on car bumpers that are the small holes needed for the ultrasonic sensors currently used,” explained Van Thillo in a press conference during ITF2016.

In an ITF2016 presentation, CEO Reinhard Ploss, discussed how Infineon works with industrial partners to create competitive commercial products. “When we first developed RADAR, there was a collaboration between the Tier-1 car companies and ourselves,” explained Ploss. “The key lies in the algorithms needed to process the data, since the raw data stream is essentially useless. The next generation of differentiation for semiconductors will be how to integrate algorithms. In effect, how do you translate ‘pixels’ into ‘optics’ without an expensive microprocessor?”

Evolution of radar technology over time has reached the miniaturization of 79 GHz using 28nm silicon CMOS technology. Imec is now also working on 140 GHz radar chips. (Source: imec)

—E.K.

IoT Demands Part 2: Test and Packaging

Friday, April 15th, 2016

By Ed Korczynski, Senior Technical Editor, Solid State Technology, SemiMD

The Internet-of-Things (IoT) adds new sensing and communications to improve the functionality of all manner of things in the world. Solid-state and semiconducting materials for new integrated circuits (IC) intended for ubiquitous IoT applications will have to be extremely small and low-cost. To understand the state of technology preparedness to meet the anticipated needs of the different application spaces, experts from GLOBALFOUNDRIES, Cadence, Mentor Graphics and Presto Engineering gave detailed answers to questions about IoT chip needs in EDA and fab nodes, as published in “IoT Demands:  EDA and Fab Nodes.” We continue with the conversation below.

Korczynski: For test of IoT devices which may use ultra-low threshold voltage transistors, what changes are needed compared to logic test of a typical “low-power” chip?

Steve Carlson, product management group director, Cadence

Susceptibility to process corners and operating conditions becomes heightened at near-threshold voltage levels. This translates into either more conservative design sign-off criteria, or the need for higher levels of manufacturing screening/tests. Either way, it has an impact on cost, be it hidden by over-design, or overtly through more costly qualification and test processes.

Jon Lanson, vice president worldwide sales & marketing, Presto Engineering

We need to make sure that the testability has also been designed to be functional structurally in this mode. In addition, sub-threshold voltage operation must account for non-linear transistor characteristics and the strong impact of local process variation, for which the conventional testability arsenal is still very poor. Automotive screening used low voltage operation (VLV) to detect latent defects, but at very low voltage close to the transistor threshold, digital becomes analog, and therefore if the usual concept still works for defect detection, functional test and @speed tests require additional expertise to be both meaningful and efficient from a test coverage perspective.

Korczynski:  Do we have sufficient specifications within “5G” to handle IoT device interoperability for all market segments?

Rajeev Rajan, Vice President of Internet of Things (IoT) at GLOBALFOUNDRIES

The estimated timeline for standardization availability of 5G is around 2020. 5G is being designed keeping three classes of applications in mind:  Enhanced Mobile Broadband, Massive IoT, and Mission-Critical Control. Specifically for IoT, the focus is on efficient, low-cost communication with deep coverage. We will start to see early 5G technologies start to appear around 2018, and device connectivity,

interoperability and marshaling the data they generate that can apply to multiple IoT sub-segments and markets is still very much in development.

Korczynski:  Will the 1st-generation of IoT devices likely include wide varieties of solution for different market-segments such as industrial vs. retail vs. consumer, or will most device use similar form-factors and underlying technologies?

Rajeev Rajan, Vice President of Internet of Things (IoT) at GLOBALFOUNDRIES

If we use CES 2016 as a showcase, we are seeing IoT “Things” that are becoming use-case or application-centric as they apply to specific sub-segments such as Connected Home, Automotive, Medical, Security, etc. There is definitely more variety on the consumer front vs. industrial. Vendors / OEMs / System houses are differentiating at the user-interface design and form-factor levels while the “under-the-hood” IC capabilities and component technologies that provide the atomic intelligence are fairly common. ​

Steve Carlson, product management group director, Cadence

Right now it seems like everyone is swinging for the fence. Everyone wants the home-run product that will reach a billion devices sold. Generality generally leads to sub-optimality, so a single device usually fails to meet the needs and expectations of many. Devices that are optimized for more specific use cases and elements of purchasing criteria will win out. The question of interface is an interesting one.

Korczynski:  Will there be different product life-cycles for different IoT market-segments, such as 1-3 years for consumer but 5-10 years for industrial?

Rajeev Rajan, Vice President of Internet of Things (IoT) at GLOBALFOUNDRIES

That certainly seems to be the case. According to Gartner’s market analysis for IoT, Consumer is expected to grow at a faster pace in terms of units compared to Enterprise, while Enterprise is expected to lead in revenue. Also the churn-cycle in Consumer is higher / faster compared to Enterprise. Today’s wearables or smart-phones are good reference examples. This will however vary by the type of “Thing” and sub-segment. For example, you expect to have your smart refrigerator for a longer time period compared to smart clothing or eyewear. As ASPs of the “Things”come down over time and new classes of products such as disposables hit the market, we can expect even larger volumes.​

Jon Lanson, vice president worldwide sales & marketing, Presto Engineering

The market segments continue to be driven by the same use cases. In consumer wearables, short cycles are linked to fashion trends and rapid obsolescence, where consumer home use has longer cycles closer to industrial market requirements. We believe that the lifecycle norms will hold true for IoT devices.

Korczynski:  For the IoT application of infrastructure monitoring (e.g. bridges, pipelines, etc.) long-term (10-20 year) reliability will be essential, while consumer applications may be best served by 3-5 year reliability devices which cost less; how well can we quantify the trade-off between cost and chip reliability?

Steve Carlson, product management group director, Cadence

Conceptually we know very well how to make devices more reliable. We can lower current densities with bigger wires, we can run at cooler temperatures, and so on.  The difficulty is always in finding optimality for a given criterion across the, for practical purposes, infinite tradeoffs to be made.

Korczynski:  Why is the talk of IoT not just another “Dot Com” hype cycle?

Rajeev Rajan, Vice President of Internet of Things (IoT) at GLOBALFOUNDRIES

​​I participated in a panel at SEMICON China in Shanghai last month that discussed a similar question. If we think of IoT as a “brand new thing” (no pun intended), then we can think of it as hype. However if we look at the IoT as as set of use-cases that can take advantage of an evolution of Machine-to-Machine (M2M) going towards broader connectivity, huge amounts of data generated and exchanged, and a generational increase in internet and communication network bandwidths (i.e. 5G), then it seems a more down-to-earth technological progression.

Nicolas Williams, product marketing manager, Mentor Graphics

Unlike the Dot Com hype, which was built upon hope and dreams of future solutions that may or may not have been based in reality, IoT is real business. For example, in a 2016 IC Insights report, we see that last year $63.4 billion in revenue was generated for IoT systems and the market is growing at about 20% CAGR. This same report also shows IoT semiconductor sales of over $15 billion in 2015 with a CAGR of 21.1%.

Jon Lanson, vice president worldwide sales & marketing, Presto Engineering

It is the investment needed up front to create sensing agents and an infrastructure for the hardware foundation of the IoT that will lead to big data and ultimately value creation.

Steve Carlson, product management group director, Cadence

There will be plenty of hype cycles for products and product categories along the way. However, the foundational shift of the connection of things is a diode through which civilization will only pass through in one direction.

IoT Demands Part 1: EDA and Fab Nodes

Thursday, April 14th, 2016

The Internet-of-Things (IoT) is expected to add new sensing and communications to improve the functionality of all manner of things in the world:  bridges sensing and reporting when repairs are needed, parts automatically informing where they are in storage and transport, human health monitoring, etc. Solid-state and semiconducting materials for new integrated circuits (IC) intended for ubiquitous IoT applications will have to be assembled at low-cost and small-size in High Volume Manufacturing (HVM). Micro-Electro-Mechanical Systems (MEMS) and other sensors are being combined with Radio-Frequency (RF) ICs in miniaturized packages for the first wave of growth in major sub-markets.

To meet the anticipated needs of the different IoT application spaces, SemiMD asked leading companies within critical industry segments about the state of technology preparedness:

*  Commercial IC HVM – GLOBALFOUNDRIES,

*  Electronic Design Automation (EDA) – Cadence and Mentor Graphics,

*  IC and complex system test – Presto Engineering.

Korczynski:  Today, ICs for IoT applications typically use 45nm/65nm-node which are “Node -3″ (N-3) compared to sub-20nm-node chips in HVM. Five years from now, when the bleeding-edge will use 10nm node technology, will IoT chips still use N-3 of 28nm-node (considered a “long-lived node”) or will 45nm-node remain the likely sweet-spot of price:performance?

Timothy Dry, product marketing manager, GLOBALFOUNDRIES

In 5 years time, there will be a spread of technology solutions addressing low, middle, and high ends of IoT applications. At the low end, IoT end nodes for applications like connected smoke

detectors, security sensors will be at 55, 40nm ULP and ULL for lowest system power, and low cost. These applications will be typically served by MCUs <50DMIPs. Integrated radios (BLE, 802.15.4), security, Power Management Unit (PMU), and eFlash or MRAM will be common features. Connected LED lighting is forecasted to be a high volume IoT application. The LED drivers will use BCD extensions of 130nm—40nm—that can also support the radio and protocol-MCU with Flash.

In the mid-range, applications like smart-meters and fitness/medical monitoring will need systems that have more processing power <300DMIPS. These products will be implemented in 40nm, 28nm and GLOBALFOUNDRIES’ new 22nm FDSOI technology that uses software-controlled body-biasing to tune SoC operation for lowest dynamic power. Multiple wireless (BLE/802.15.4, WiFi, LPWAN) and wired connectivity (Ethernet, PLC) protocols with security will be integrated for gateway products.

High-end products like smart-watches, learning thermostats, home security/monitoring cameras, and drones will require MPU-class IC products (~2000DMIPs) and run high-order operating systems (e.g. Linux, Android). These products will be made in leading-edge nodes starting at 22FDX, 14FF and migrating to 7FF and beyond. Design for lowest dynamic power for longest battery life will be the key driver, and these products typically require human machine Interface (HMI) with animated graphics on a high resolution displays. Connectivity will include BLE, WiFi and cellular with strong security.

Steve Carlson, product management group director, Cadence

We have seen recent announcements of IoT targeted devices at 14nm. The value created by Moore’s Law integration should hold, and with that, there will be inherent advantages to those who leverage next generation process nodes. Still, other product categories may reach functionality saturation points where there is simply no more value obtained by adding more capability. We anticipate that there will be more “live” process nodes than ever in history.

Jon Lanson, vice president worldwide sales & marketing, Presto Engineering

It is fair to say that most IoT devices will be a heterogeneous aggregation of analog functions rather than high power digital processors. Therefore, and by similarity with Bluetooth and RFID devices, 90nm and 65nm will remain the mainstream nodes for many sub-vertical markets, enabling the integration of RF and analog front-end functions with digital gate density. By default, sensors will stay out of the monolithic path for both design and cost reasons. The best answer would be that the IoT ASIC will follow eventually the same scaling as the MCU products, with embedded non-volatile memories, which today is 55-40nm centric and will move to 28nm with industry maturity and volumes.

Korczynski:  If most IoT devices will include some manner of sensor which must be integrated with CMOS logic and memory, then do we need new capabilities in EDA-flows and burn-in/test protocols to ensure meeting time-to-market goals?

Nicolas Williams, product marketing manager, Mentor Graphics

If we define a typical IoT device as a product that contains a MEMS sensor, A/D, digital processing, and a RF-connection to the internet, we can see that the fundamental challenge of IoT design is that teams working on this product need to master the analog, digital, MEMS, and RF domains. Often, these four domains require different experience and knowledge and sometimes design in these domains is accomplished by separate teams. IoT design requires that all four domains are designed and work together, especially if they are going on the same die. Even if the components are targeting separate dice that will be bonded together, they still need to work together during the layout and verification process. Therefore, a unified design flow is required.

Stephen Pateras, product marketing director, Mentor Graphics

Being able to quickly debug and create test patterns for various embedded sensor IP can be addressed with the adoption of the new IEEE 1687 IP plug-and-play standard. If a sensor IP block’s digital interface adheres to the standard, then any vendor-provided data required to initialize or operate the embedded sensor can be easily and quickly mapped to chip pins. Data sequences for multiple sensor IP blocks can also be merged to create optimized sequences that will minimize debug and test times.

Jon Lanson, vice president worldwide sales & marketing, Presto Engineering

From a testing standpoint, widely used ATEs are generally focused on a few purposes, but don’t necessarily cover all elements in a system. We think that IoT devices are likely to require complex testing flows using multiple ATEs to assure adequate coverage. This is likely to prevail for some time as short run volumes characteristic of IoT demands are unlikely to drive ATE suppliers to invest R&D dollars in creating new purpose-built machines.

Korczynski:  For the EDA of IoT devices, can all sensors be modeled as analog inputs within established flows or do we need new modeling capability at the circuit level?

Steve Carlson, product management group director, Cadence

Typically, the interface to the physical world has been partitioned at the electrical boundary. But as more mechanical and electro-mechanical sensors are more deeply integrated, there has been growing value in co-design, co-analysis, and co-optimization. We should see more multi-domain analysis over time.

Nicolas Williams, product marketing manager, Mentor Graphics

Designers of IoT devices that contain MEMS sensors need quality models in order to simulate their behavior under physical conditions such as motion and temperature. Unlike CMOS IC design, there are few standardized MEMS models for system-level simulation. State of the art MEMS modeling requires automatic generation of behavioral models based on the results of Finite Element Analysis (FEA) using reduced-order modeling (ROM). ROM is a numerical methodology that reduces the analysis results to create Verilog-A models for use in AMS simulations for co-simulation of the MEMS device in the context of the IoT system.

RF and MEMS Technologies to Enable the IoT

Friday, October 24th, 2014

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By Ed Korczynski, Sr. Technical Editor, Solid State Technology and SemiMD

The “Internet of Things” (IoT) has been seen as the next major market that will demand high volumes of integrated circuits (IC). The IoT can be loosely defined as a network of small, low-cost, ubiquitous electronic devices where sensing data and communicating information occurs without direct human intervention. Each device would function as a “smart node” in the network by doing some low-level signal processing to filter signals from noise, and to reduce the bandwidth needed for node-to-node communications. The nodes will need to communicate up to some manner of a “cloud” for secure memory storage and to bounce actionable information down to humans.

Figure 1 shows a conservative forecast of the global IoT market that was recently published by IDC. IDC expects the worldwide IoT installed base to experience a compound annual growth rate (CAGR) of 17.5% from 2013 to 2020, starting from 9.1 billion smart nodes installed at the end of 2013 and growing to 28.1 billion units by 2020.

FIGURE 1: Forecast for global IoT applications revenue 2013-2020. Note that smart node “intelligent systems/devices” provide the foundation for this huge growing market. (Source: IDC)

Due to the anticipated elastic-demand for IoT devices that would come from cost reductions, the forecasts for the number of IoT nodes ranges to 50 billion or even 80 billion by the year 2020, as documented in the recent online Pete’s Post “Don’t Hack My Light Bulb, Bro”. The post also provides an excellent overview of recent discussions regarding the host of additional technology and business challenges associated with the enterprise infrastructure and security issues surrounding the integration of vast streams of new information.

As shown in Figure 1, the smart nodes form the foundation for the whole IoT. Consequently, the world will need low-cost high-volume manufacturing (HVM) technologies to create the different functionalites needed for smart nodes. Sensor- and logic-technologies to enable IoT smart nodes will generally evolve from existing IC applications, while R&D continues in Radio Frequency (RF) communications and in Micro Electro-Mechanical Systems (MEMS) energy harvesting.

RF Technology

IoT smart-nodes will use wireless RF technologies to communicate between themselves and with the “cloud.” In support of rapid growth in the 71-86 GHz RF “E-band” telecom backhaul segment—which transports data from cell sites in the peripheral radio access network (RAN) to the wireless packet core—Presto Engineering recently announced a non-captive production-scale testing service for 50µm-thin gallium arsenide wafers.

Silicon-On-Insulator (SOI) substrate supplier Soitec has excellent perspective on the global market for RF chips, since it’s High-Resistivity SOI (HR-SOI) wafers are widely used in commercial fabs. Bernard Aspar, senior vice president and general manager of the Communications and Power business unit of Soitec, explained to SemiMD in an exclusive interview why the market for RF chips is growing rapdily. RF front-end module unit sales are forecasted to increase at a CAGR of ~16% over the period of 2013-2017, while the area of silicon needing to be delivered could actually increase at ~30% CAGR. RF chips are increasing in average size due to the need to integrate multiple standards for wireless communications and multiple antenna switches. “The first components to be integrated in silicon were the antenna switches, moving from 70% on GaAs in 2010 to more than 80% on SOI in 2014,“ said Aspar.

Soitec claims that >80% of smart-phones today use an RF chip built on a wafer from the company, based on sales last year of >300k 200mm HR-SOI wafers. Due to anticipated future growth in RF demand, the company has plans to eventually move HR-SOI production to 300mm diameter wafers. Most of the anticipated demand will be for the company’s new variant of HR-SOI called eSI (“enhanced Signal Integrity”previously called “Trap Rich”) with a measured effective resistivity as high as 10 kOhm-cm for improved device performance.

This high-resistivity characteristic, which is conserved after a full CMOS process, translates to very low RF insertion loss (< 0.15 dB/mm at 1 GHz) and purely capacitive crosstalk similar to quartz substrates. HR-SOI substrates in general demonstrate reduced harmonics compared with standard SOI substrates, and the eSI wafers reduce harmonics to the point that they can be considered as lossless. Soitec was recently given a Best Partnership Award by Sony Semiconductor for supplying RF substrates.

“We’re also adding value to the substrate because it allows for simplification of the fab processing,” said Aspar. The eSI wafers enable much higher linearity and isolation, helping designers to address some of the most advanced LTE requirements at competitive costs. These substrates also provides benefits for the integration of passives, such as the quality factor of spiral inductors or tunable MEMS capacitors.

Vibrational Energy Harvesting

IoT smart nodes will need electrical power to function, and batteries that must be replaced or charged by an external source create issues for ubiquitous always-on small devices. In principle the ambient energies of the environment can be harvested to power smart nodes, and to do so we may consider using thermoelectric, photovoltaic, and piezoelectric properties of thin-films. Thermoelectric and photovoltaic devices both require somewhat specialized ambients for efficient energy harvesting, while piezoelectric devices can extract energy from subtle vibrations almost anywhere in the world (Fig. 2).

FIGURE 2: Schematic cross-section of piezoelectric cantilever with end mass, depicted in connection to an energy-harvesting circuit. (Source: Science)

Researchers in the Energy Harvesting and Mechatronics Research Lab at Stony Brook University, New York, recently published an excellent overview of the potential for 1 W to 100 kW piezoelectronic energy harvesting in building, automobiles, and wearables electronics in the Journal of Intelligent Material Systems and Structures 24(11) 1405-1430. However, the largest forecasted growth in the IoT is for small devices that would consume µW to mW of active power.

For low-cost and low-power consumption, the logic chips for IoT smart nodes are expected to be made using a 65nm “trailing edge” fab process. For example, CAST Inc. has developed a 32-bit BA20 embedded processor core that can deliver 3.41 CoreMarks/MHz at a maximum frequency of 75 MHz. Using TSMC’s 65nm Low Power fab process, it occupies only 0.01 mm2 of silicon area while consuming 2 µW/MHz. Thus, at maximum speed the chip core would consume just 150µW.

MicroGen Systems, Inc. (MicroGen) is a privately held company developing thin piezoelectric energy harvesters, based on technology from Cornell University’s NanoScale Science and Technology Facility. Founded in 2007, MicroGen has headquarters and R&D in the Ithaca and Rochester, NY areas, and volume manufacturing with X-FAB in Itzehoe, Germany. Figure 3 shows one of the company’s ~100 mm2 area chips featuring an aluminum nitride (AlN) peizoelectric thin-film on a cantilever that produces alternating current (AC) electricity in response to external vibrations. Different cantilever designs allow for harvesting energy from either single-frequency or broadband vibrations. At resonance the AC power output is maximized, so it can be ~100 µW at 120Hz and 0.1g, or ~900 µW at 600Hz and 0.5g.

FIGURE 3: BOLT™-R0600 energy-harvesting chip without packaging. The green-silver trapezoidal area is a 25-100µm thick cantilever (with several thin-film layers including an AlN piezoelectric) attached to grey rectangular end mass (silicon). A fixed-frequency device, at resonance of ~600Hz it can produce ~900 µWatts of AC power. (Source: MicroGen Systems)

For any piezoelectric energy harvester there are basic materials properties that must be optimized, including the piezoelectric strain constant as well as the electromechanical coupling factor of the thin-film to the moving mass. Lead-zirconium-titanate (PZT) has been the most studied piezoelectric thin-film due to high strain constant and ability to couple to a substrate though the use of buffer layers.

S. H. Baek, et al. showed “Piezoelectric MEMS with Giant Piezo Actuation” in Science 18 November 2011, Vol 344 using lead-manganese-niobate with lead-titanate (PMN-PT) layers epitaxially grown on a strontium-titanate (STO) buffer layer over 4°-off-axis(001)Si. Figure 4 shows both the transverse piezoelectric coefficient (C/m2) and the energy-harvesting figure of merit (GPa) for this and other thin-films. Note that to acheive stable “giant” piezoelectric effects the PMN-PT layer had to be grown epitaxially with precise control over the STO grain orientation.

FIGURE 4: Transverse piezoelectric coefficient (C/m2) and the energy-harvesting figure of merit (GPa) for PMN-PT (“this work”) and other piezoelectric thin-films. (Source: Science)

—E.K.