Tag Archive R&D

Great line-up planned for IEEE S3S (SOI, 3D and low-voltage — 5-8 October, Sonoma, CA). Advance Program available. Registration still open.


Now in its third year, the 2015 IEEE S3S Conference has evolved into the premier venue for sharing the latest and most important findings in the areas of process integration, advanced materials & materials processing, and device and circuit design for SOI, 3D and low-voltage microelectronics. World-class leading experts in their fields will come to this year’s S3S Conference to present, discuss and debate the most recent breakthroughs in their research.

This year’s program includes:


The conference also features several events tailored for socialization and peer-to-peer discussions, such as the welcome reception, the cookout and the interactive Poster & Reception Session which is a great place to meet new colleagues and learn and exchange insights on technical topics. Enjoy a light snack and a beverage of your choice while meandering around to meet and discuss technical issues with long-time colleagues and make connections with new and influential experts and decision makers in your field.

Take time to visit the local attractions of Sonoma County. Sonoma is well known for outdoor recreation, spas, golf, night life, shopping, culinary activities, arts and music and wineries. It is truly my pleasure to serve as the General Chair of the 2015 Conference. —Bruce Doris

Download the Advance Program

Find all the details about the conference on our website: s3sconference

Click here to go directly to the IEEE S3S Conference registration page.

Click here for hotel information. To be sure of getting a room at the special conference rate book before 18 September 2015.

S3S Conference

The DoubleTree by Hilton Sonoma Wine Country, One Doubletree Drive, Rohnert Park, CA 94928

October 5th thru 8th, 2015

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LIgroupS3SJoin the IEEE S3S Conference group on LinkedIn to follow the news — click here or search on LinkedIn for IEEE S3S.

SOI Radiation Detector Workshop – Registration Extended (SOIPIX2015 – June, Japan)

SOIPIX15International research teams working on or interested in the far-reaching SOIPIX radiation-detector project have a workshop coming up in June. The project was originally started by KEK* scientists to develop a new detector technology and quantum beam imaging for high-energy particle physics. As research teams around the world (including Japan, USA, China and Europe) joined to take advantage of the multi-wafer project runs, it soon expanded to include more applications. (To learn more about the program, click here.)

Leveraging the SOIPIX strategy of SOI-based monolithic sensor-electronics integration, applications are now being developed in areas such as medical (x-ray sensors and radiotherapeutic systems), materials research, nuclear physics, astrophysics, electron microscopy and industrial uses (such as x-ray inspection systems).

(Here at ASN, we covered the project and its implications for medical imaging back in 2010 – click here to read that piece.)

The next workshop, SOIPIX2015, will take place at Tohoku University (Sendai, Japan) 3-5 June 2015. Registration has been extended until 22 May 2015. Click here for registration information.

 *KEK is Japan’s High Energy Accelerator Research Organization.

European R&D Leaders Team on SOI-MEMS Platform for Industry, SME’s

The Heterogeneous Technology Alliance (HTA), a coalition of top European R&D organizations, is offering an SOI-MEMS platform. Looking to bridge the gap between academia and industry, this technological platform pools the SOI-MEMS expertise, capabilities and fabrication facilities of Leti (France), Fraunhofer (Germany), CSEM (Switzerland) and VTT (Finland).

The main focus of HTA (click here for the website) is the further development of innovative Smart Systems. SOI-MEMS is typically used for silicon oscillators, microphones, speakers, compass, navigation, motion sensors, sensors and actuators, energy harvesting, micro fuel cells, microfluidics and other deep reactive-ion etched micro structures. A recently issued brochure gives an overview of the offering.

The HTA is active at all levels of Smart Integrated Systems Solutions: from applied research on materials, processes and equipment through the fabrication of devices and components to the development of new products and services. Development and small-scale production cleanrooms for micro-electronics, MEMS, power electronics and analogue components is available. Wafer handling capacity encompasses wafer sizes ranging from 100, through 150 and 200 to 300 mm.

A one-stop shop for complete system solutions, the HTA guarantees simple access to an enlarged portfolio of technologies and is structured to facilitate technology transfer to European and non-European companies. In addition to working with large industrial partners, the HTA offers services specially suited for small and medium-sized companies. With a combined staff of more than 5,000 scientists and a portfolio of more than 3,000 patents, the HTA is de facto the largest European organization in the field.


SOI for MEMS, NEMS, sensors and more at IEDM ’14 (Part 3 of 3 in ASN’s IEDM coverage)

iedm_logoImportant SOI-based developments in MEMS, NEMS (like MEMS but N for nano), sensors and energy harvesting shared the spotlight with advanced CMOS and future devices at IEDM 2014 (15-17 December in San Francisco). IEDM is the world’s showcase for the most important applied research breakthroughs in transistors and electronics technology.

Here in Part 3, we’ll cover these remaining areas. (In Part 1 of ASN’s IEDM coverage, we had a rundown of the top papers on FD-SOI and SOI-FinFETs. Part 2 looked at papers covering future device architectures leveraging SOI.)

Summaries culled from the abstracts follow.


4.2: Three-Dimensional Integrated CMOS Image Sensors with Pixel-Parallel A/D Converters Fabricated by Direct Bonding of SOI Layers

M. Gotoet al (NHK Research Labs, U Tokyo)

This illustration (a) shows a schematic diagram of the 3D integrated CMOS image sensor; (b) shows a conceptual diagram of the image sensor pixel; (c) is a cross-sectional scanning electron microscope image of a bonded CMOS image sensor pixel with no voids observed at the bonded interface and with the upper layer thinned to 6.5 µm; and (d) is a photograph of the bonded CMOS image sensor array, where 60-µm-square photodiodes (PD) are stacked on inverters.(NHK paper 4.2 at IEDM '14)

This illustration (a) shows a schematic diagram of the 3D integrated CMOS image sensor; (b) shows a conceptual diagram of the image sensor pixel; (c) is a cross-sectional scanning electron microscope image of a bonded CMOS image sensor pixel with no voids observed at the bonded interface and with the upper layer thinned to 6.5 µm; and (d) is a photograph of the bonded CMOS image sensor array, where 60-µm-square photodiodes (PD) are stacked on inverters.(NHK paper 4.2 at IEDM ’14)

The resolutions and frame rates of CMOS image sensors have increased greatly to meet demands for higher-definition video systems, but their design may soon be obsolete. That’s because photodetectors and signal processors lie in the same plane, on the substrate, and many pixels must time-share a signal processor. That makes it difficult to improve signal processing speed. NHK researchers developed a 3D parallel-processing architecture they call “pixel-parallel” processing, where each pixel has its own signal processor. Photodetectors and signal processors are built in different vertically stacked layers. The signal from each pixel is vertically transferred and processed in individual stacks.

3D stacking doesn’t degrade spatial resolution, so both high resolution and a high frame rate are achieved. 3D stacked image sensors have been reported previously, but they either didn’t have a signal processor in each stack or they used TSV/microbump technology, reducing resolution. NHK discusses how photodiode and inverter layers were bonded with damascened gold electrodes to provide each pixel with analog-to-digital conversion and a pulse frequency output. A 64-pixel prototype sensor was built, which successfully captured video images and had a wide dynamic range of >80 dB, with the potential to be increased to >100dB.


4.5: Experimental Demonstration of a Stacked SOI Multiband Charged-Coupled Device

C.-E. Chang et al (Stanford, SLAC)

Multiband light absorption and charge extraction in a stacked SOI multiband CCD are experimentally demonstrated for the first time. This proof of concept is a key step in the realization of the technology which promises multiple-fold efficiency improvements in color imaging over current filter- and prism-based approaches.


15.4: A Semiconductor Bio-electrical Platform with Addressable Thermal Control for Accelerated Bioassay Development

T.-T. Chen et al (TSMC, U Illinois),

In this work, the researchres introduce a bioelectrical platform consisting of field effect transistor (FET) bio-sensors, temperature sensors, heaters, peripheral analog amplifiers and digital controllers, fabricated by a 0.18μm SOI-CMOS process technology. The bio-sensor, formed by a sub-micron FET with a high-k dielectric sensing film, exhibits near-Nernst sensitivity (56-59 mV/pH) for ionic detection. There were also 128×128 arrays tested by monitoring changes in enzyme reactions and DNA hybridization. The electrical current changes correlated to changes in pH reaching -1.387μA/pH with 0.32μA standard variation. The detection of urine level via an enzyme(urease)-catalyzed reaction has been demonstrated to a 99.9% linearity with 0.1μL sample volume. And the detection of HBV DNA was also conducted to a 400mV equivalent surface potential change between 1 μM matched and mismatched DNA. As a proof of concept, they demonstrated the capabilities of the device in terms of detections of enzymatic reaction and immobilization of bio-entities.  The proposed highly integrated devices have the potential to largely expand its applications to all the heat-mediated bioassays, particularly with 1-2 order faster thermal response within only 0.5% thermal coupling and smaller volume samples. This work presents an array device consisting of multiple cutting-edge semiconductor components to assist the development of electrical bio assays for medical applications.



22.1: Nanosystems Monolithically Integrated with CMOS: Emerging Applications and Technologies

J. Arcamone et al (U Grenoble, Leti, Minatec),

This paper reviews the last major realizations in the field of monolithic integration of NEMS with CMOS. This integration scheme drastically improves the efficiency of the electrical detection of the NEMS motion. It also represents a compulsory milestone to practically implement breakthrough applications of NEMS, such as mass spectrometry, that require large capture cross section (VLSI-arrayed NEMS) and individual addressing (co-integration of NEMS arrays with CMOS electronic loop).


22.2: A Self-sustained Nanomechanical Thermal-piezoresistive Oscillator with Ultra-Low Power Consumption

K.-H. Li et al (National Tsing Hua U)

This work demonstrates wing-type thermal-piezoresistive oscillators operating at about 840 kHz under vacuum with ultralow power consumption of only 70 µW for the first time. The thermally-actuated piezoresistively-sensed (i.e., thermalpiezoresistive) resonator can achieve self-sustained oscillation using a sufficient dc bias current through its thermal beams without additional electronic circuits. By using proper control of silicon etching (ICP) recipe, the submicron cross-sectional dimension of the thermal beams can be easily and reproducibly fabricated in one process step.


22.4: High Performance Polysilicon Nanowire NEMS for CMOS Embedded Nanosensors

I. Ouerghiet al (Leti)

The researchers present for the first time sub-100nm poly-Silicon nanowire (poly-Si NW) based NEMS resonators for low-cost co-integrated mass sensors on CMOS featuring excellent performance when compared to crystalline silicon. In particular, comparable quality factors (130 in the air, 3900 in vacuum) and frequency stabilities are demonstrated when compared to crystalline Si. The minimum measured Allan deviation of 7×10-7 leads to a mass resolution detection down to 100 zg (100×10-2 g). Several poly-Si textures are compared and the impact on performances is studied (quality factor, gauge factor, Allan variances, noise, temperature dependence (TCR)). Moreover a novel method for in-line NW gauges factor (GF) extraction is proposed and used.


22.5: Integration of RF MEMS Resonators and Phononic Crystals for High Frequency Applications with Frequency-selective Heat Management and Efficient Power Handling

H. Campanella et al (A*STAR, National U Singapore)

A radio frequency micro electromechanical system (RFMEMS) Lamb-wave resonator made of aluminum nitride (AlN) that is integrated with AlN phononic crystal arrays to provide frequency-selective heat management, improved power handling capability, and more efficient electromechanical coupling at ultra high frequency (UHF) bands. RFMEMS+PnC integration is scalable to microwave bands.


22.6: A Monolithic 9 Degree of Freedom (DOF) Capacitive Inertial MEMS Platform

I. E. Ocak et al  (IME, A*STAR Singapore)

A 9 degree of freedom inertial MEMS platform, integrating 3 axis gyroscopes, accelerometers, and magnetometers on the same substrate is presented. This method reduces the assembly cost and removes the need for magnetic material deposition and axis misalignment calibration. Platform is demonstrated by comparing fabricated sensor performances with simulation results.


15.6: MEMS Tunable Laser Using Photonic Integrated Circuits

M. Ren et al (Nanyang Technological University, A*STAR)

This paper reports a monolithic MEMS tunable laser using silicon photonic integrated circuit, formed in a ring cavity. In particular, all the necessary optical functions in a ring laser system, including beam splitting/combining, isolating, coupling, are realized using the planar passive waveguide structures. Benefited from the high light-confinement capability of silicon waveguides, this design avoids beam divergence in free-space medium as suffered by conventional MEMS tunable lasers, and thus guarantees superior performance. The proposed laser demonstrates large tuning range (55.5 nm),excellent single-mode properties (50 dB side-mode-suppression ratio (SMSR) and 130 kHz linewdith), compact size (3mm × 2mm), and single-chip integration without other separated optical elements.


Energy Harvesting

8.4: A High Efficiency Frequency Pre-defined Flow-driven Energy Harvester Dominated by On-chip Modified Helmholtz Resonating Cavity

X.J. Mu et al (A*STAR)

The researchers present a novel flow-driven energy harvester with its frequency dominated by on-chip modified Helmholtz Resonating Cavity (HRC). This device harvests pneumatic kinetic energy efficiently and demonstrates a power density of 117.6 μW/cm2, peak to peak voltage of 5 V, and charging of a 1 μF capacitor in 200 ms.

8.5: Fabrication of Integrated Micrometer Platform for Thermoelectric Measurements

M. Haras et al  (IEMN, ST)

Preliminary simulations of lateral thermo-generators showed that silicon’s harvesting capabilities, through a significant thermal conductivity reduction, could compete with conventional thermoelectric materials, offering additional: CMOS compatibility; harmlessness and cost efficiency. The researchers report the fabrication and characterization of integrated platforms showing a threefold reduction of thermal conductivity in 70nm thick membranes.


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This has been the 3rd post in a 3-part series. Part 1 (click here to  read it) of ASN’s IEDM ’14 coverage gave a rundown of the top FD-SOI and SOI-FinFET papers.  Part 2 (click here to  read it) looked at papers covering SOI-based future device architectures.


SOI-based future device structures at IEDM ’14 (Part 2 of 3 in ASN’s IEDM coverage)

iedm_logoBeyond FD-SOI and FinFETs, important SOI-based developments in advanced device architectures including nanowires (NW), gate all around (GAA) and other FET structures shared the spotlight at IEDM 2014 (15-17 December in San Francisco). IEDM is the world’s showcase for the most important applied research breakthroughs in transistors and electronics technology.

Here in Part 2 of ASN’s IEDM coverage, we’ll cover future device architectures. In Part 1, we had a rundown of the top SOI-based advanced CMOS papers. In Part 3 we’ll look at MEMS, NEMS, sensors and more.

Summaries culled from the abstracts follow.

16.2: Dual-Channel CMOS Co-Integration with Si Channel NFET and Strained-SiGe Channel PFET in Nanowire Device Architecture Featuring 15nm Gate Length

P. Nguyen et al (Leti, ST, Soitec)


Omega-gate CMOS nanowire transistors, with a diameter of 12nm and gate length of 15nm. The NFETs have a silicon channel while the PFETs have a SiGe channel. The germanium (Ge) content is estimated to be 30%. (Courtesy: Leti, ST, Soitec at IEDM 14, Paper 16.2)

Omega-gate CMOS nanowire transistors, with a diameter of 12nm and gate length of 15nm. The NFETs have a silicon channel while the PFETs have a SiGe channel. The germanium (Ge) content is estimated to be 30%. (Courtesy: Leti, ST, Soitec at IEDM
14, Paper 16.2)

The researchers have fabricated the first hybrid channel omega-gate CMOS nanowire (NW) with strained SiGe-channel (cSiGe) p-FETs and Si-channel n-FET. An optimized process flow based on the Ge enrichment technique results in a +135% hole mobility enhancement at long gate lengths compared to Si. Effectiveness of cSiGe channel is also evidenced for ultra-scaled p-FET NW (LG=15 nm) with +90% ION current improvement. [110]-oriented NW is shown to be the best candidate to improve drive current under compressive strain. In this work, the strain is measured by using precession electron diffraction with a 1nm spatial resolution. Furthermore, they show that hybrid integration reduces the delay of CMOS ring oscillator (FO=3) by 50% at VDD=0.9V. Finally, they demonstrate the most aggressively scaled hybrid CMOS NWs reported to date with NW width and gate length down to 7nm and 11nm, while maintaining high drive current (687µA/µm for p-FET and 647µA/µm for n-FET) with low leakage current and excellent short-channel-control (DIBL<50mV/V).


20.5: Study of the Piezoresistive Properties of NMOS and PMOS Omega-Gate SOI Nanowire Transistors: Scalability Effects and High Stress Level

J. Pelloux-Prayer et al (Leti, Soitec, Tokyo Tech)

The researchers present a comprehensive study of piezoresistive properties of aggressively scaled MOSFET devices. For the first time, the evolution of the piezoresistive coefficients with scaled dimensions is presented (gate length down to 20nm and channel width down to 8nm), and from the low to high stress regime (above 1GPa). They show that the downscaling of geometrical parameters doesn’t allow the use of the conventional definition of piezoresistivity tensor elements. The obtained results give a comprehensive insight on strain engineering ability in aggressively scaled CMOS technology.


20.3: Direct Observation of Self-heating in III-V Gate-all-around Nanowire MOSFETs

S.H. Shin et al (Purdue U)

Multi-gate devices, such as, FinFET, Gate-all-around transistors (GAA-FET) improve 3D electrostatic control of the channel, but the corresponding increase in self-heating may compromise both performance and reliability. Although the self-heating effect (SHE) of FinFET appears significant, but tolerable, the same may not be true for GAA geometry, especially in quasi-ballistic regime where hot spots and non-classical heat-dissipation pathways may lead to localized damage. The existing reports of the SHE on the SOI, FinFET or GAA-FET have so far relied either on indirect electrical measurements with inherent temporal delays, or on optical infra-red (λ>1.5μm ) imaging that cannot resolve deep submicron features. As a result, it has so far been impossible to resolve the spatio-temporal features of SHE fully. In this paper, the researchers develop an ultra-fast, high resolution thermo-reflectance (TR) imaging technique to (i) directly observe the local temperature rise of GAA-FET with different number of nanowires (NW)(ii) characterize/interpret the time constants of heating and cooling through high resolution transient measurements, (iii) identify critical paths for heat dissipation, and (iv) detect in-situ time-dependent breakdown of individual NW.


9.6: In-situ Doped and Tensilely Stained Ge Junctionless Gate-all-around nFETs on SOI Featuring Ion = 828µA/µm, Ion/Ioff ~ 1×105, DIBL= 16-54 mV/V, and 1.4X External Strain Enhancement

I-H. Wong et al (Taiwan U)

In-situ CVD doping and laser annealing can reach [P] and tensile strain as high as 2×1020 cm-3 and 0.37%. Junctionless Ge gate-all-around nFETs with 9 nm-Wfin and 0.8 nm-EOT achieves the record high Ion of 828 µA/µm. The Ion enhancement of ~40% is achieved under the tensile strain of 0.25%.


27.6: Flexible High-performance Nonvolatile Memory by Transferring GAA Silicon Nanowire SONOS onto a Plastic Substrate

J.-M. Choi et al (KAIST, NASA)

Flexible nonvolatile memory is demonstrated with excellent memory properties comparable to the traditional wafer-based rigid type of memory. This  achievement is realized through the transfer of an ultrathin film consisting of single crystalline silicon nanowire (SiNW) gate-all-around (GAA) SONOS memory devices onto a plastic substrate from a host silicon wafer.

13.2: High Ion/Ioff Ge-source Ultrathin Body Strained-SOI Tunnel FETs – Impact of Channel Strain, MOS Interfaces and Back Gate on the Electrical Properties

M. Kim et al (U Tokyo)

The researchers demonstrated Ge/strained-Si hetero-junction TFETs with in-situ B doped Ge. The increase in channel strain and optimization of PMA have successfully realized high performance of steep SSmin below 30 mV/dec and large Ion/Ioff ratio over 3×107.

13.3: Comprehensive Performance Re-assessment of TFETs with a Novel Design by Gate and Source Engineering from Device/Circuit Perspective

Q. Huang et al (Peking U)

In this paper, a novel TFET design, called Pocket-mSTFET, is proposed and experimentally demonstrated by evaluating the performance from device metrics to circuit implementation for low-power SoC applications. For the first time, from a circuit design perspective, TFETs performance in terms of ION, IOFF, subthreshold slope (SS), output behavior, capacitance, delay, noise and gain are experimentally benchmarked and also compared with MOSFET. By gate and source engineering without area penalty, the compatibly-fabricated Pocket-mSTFET on SOI substrate shows superior performance with the minimum SS of 29mV/dec at 300K, high ION (~20μA/μm) and large ION/IOFF ratio (~108) at 0.6V. Circuit-level implementation based on Pocket-mSTFET also shows significant improvement on energy efficiency and power reduction at VDD of 0.4V, which indicates great potential of this TFET design for low-power digital and analog applications.

13.4: A Schottky-Barrier Silicon FinFET with 6.0 mV/dec Subthreshold Slope over 5 Decades of Current

J. Zhang et al (EPFL)

The researchers demonstrate a steep subthreshold slope silicon FinFET with Schottky source/drain. The device shows a minimal SS of 3.4 mV/dec and an average SS of 6.0 mV/dec over 5 decades of current swing. Ultra-low leakage floor of 0.06 pA/μm is also achieved with high Ion/Ioff ratio of 107.


26.2: Thin-Film Heterojunction Field-Effect Transistors for Ultimate Voltage Scaling and Low-Temperature Large-Area Fabrication of Active-Matrix Backplanes

B. Hekmatshoar et al (IBM)

Heterojunction field-effect thin-film transistors with crystalline Si channels and gate regions comprised of hydrogenated amorphous silicon or organic materials are demonstrated. The HJFET devices are processed at 200ºC and room temperature, respectively; and exhibit operation voltages below 1V, subthreshold slopes of 70-100mV/dec and off currents as low as 25 fA/um.


26.7 Performance Enhancement of a Novel P-type Junctionless Transistor Using a Hybrid Poly-Si Fin Channel for 3D IC Applications

Y.-C. Cheng et al (National Tsing Hua U, National Chiao Tung U)

The hybrid fin poly-Si channel junctionless field-effect transistors (FET) are fabricated first. This novel devices show stable temperature/reliability characteristics, and excellent electrical performances in terms of steep SS (64mV/dec), high Ion/Ioff (>107) and small DIBL (3mV/V). The devices are highly promising for future further scaling and 3D stacked ICs applications.


35.1: A Physics-based Compact Model for FETs from Diffusive to Ballistic Carrier Transport Regimes

S. Rakhejaet al (MIT, Purdue U)

The virtual source (VS) model provides a simple, physical description of transistors that operate in the quasi-ballistic regime. Through comparisons to measured data, key device parameters can be extracted. The VS model suffers from three limitations: i) it is restricted to short channels, ii) the transition between linear and saturation regions is treated empirically, and iii) the injection velocity cannot be predicted, it must be extracted by fitting the model to measured data. This paper discusses a new model, which uses only a few physical parameters and is fully consistent with the VS model. The new model: i) describes both short and long channel devices, ii) provides a description of the current at any drain voltage without empirical fitting, and iii) predicts the injection velocity (device on-current). The accuracy of the model is demonstrated by comparison with measured data for III-V HEMTs and ETSOI Si MOSFETs.


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This is the 2nd post in a 3-part series. Part 1 (click here to  read it) of ASN’s IEDM ’14 coverage gave a rundown of the top FD-SOI and SOI-FinFET papers.  Part 3 (click here to read it) covers SOI-based MEMS, NEMS, sensors and more.


Soitec and SK Innovation collaborate on advanced semiconductor materials for IoT and communications

SOI wafer and advanced substrate leader Soitec and Korea’s SK Innovation (SKI) recently signed a Collaboration Agreement (CA) to establish a strategic alliance (read the press release here). The focus is on accelerating innovation in the area of semiconductor materials for information communication technologies and internet-of-things applications.

The collaborative partnership will build on the synergy between the companies. SKI is known as the leader of Korea’s energy industry, with over five decades in the fields of energy, lubricants, petrochemicals, organic materials, information electronic materials, and lithium-ion batteries.

At the outset, the alliance will focus on innovating engineered substrates and the processes for fabricating these materials. However, it could be extended to include manufacturing and commercial development. The partners’ joint goal is to bring the first products to market by early 2017 in applications. These breakthrough products will allow Soitec to grow its global market presence.

“Our partnership gives SK Innovation and Soitec the power to develop new materials and very quickly bring innovations to market,” said Carlos Mazure, Soitec’s chief technical officer. “This is a very important first step for Soitec as we team up with Korea’s leader in energy and materials development to leverage our two companies’ strong synergies.”

10nm FD-SOI, SOI FinFETs at IEDM ’14 (Part 1 of 3 in ASN’s IEDM coverage)

iedm_logoFD-SOI at 10nm (and other nodes) as well as SOI FinFETs shared the spotlight at IEDM 2014 (15-17 December in San Francisco), the world’s showcase for the most important applied research breakthroughs in transistors and electronics technology.

There were about 40 SOI-based papers presented at IEDM. Here in Part 1 of ASN’s IEDM coverage, we have a rundown of the top SOI-based advanced CMOS papers. In Part 2, we’ll cover papers on future device architectures. In Part 3 we’ll look at the papers on MEMS, NEMS, sensors and more.

Summaries culled from the abstracts follow.


The FD-SOI Papers

9.1: FD-SOI CMOS Devices Featuring Dual Strained Channel and Thin BOX Extendable to the 10nm Node.

Q. Liu et al (STMicroelectronics, CEA-LETI, IBM, Soitec)

In their IEDM ‘14 paper 9.1 on 10nm FD-SOI, ST, IBM, Leti and Soitec reported a low-temperature process that was developed to form a defect-free SiGe channel from the strained SOI starting substrate. (Image courtesy: ST et al, IEDM 2014)

In their IEDM ‘14 paper 9.1 on 10nm FD-SOI, ST, IBM, Leti and Soitec reported a low-temperature process that was developed to form a defect-free SiGe channel from the strained SOI starting substrate. (Image courtesy: ST et al, IEDM 2014)

In this work, researchers from STMicroelectronics and the IBM Technology Development Alliance demonstrate the successful implementation of strained FDSOI devices with LG, spacer & BOX dimensions scaled to 10nm feature sizes.

Two additional enabling elements for scaling FD-SOI devices to the 10nm node are reported: advanced strain techniques for performance improvement, and reduced BOX thickness for better SCE & higher body factor. The researchers also report the first demonstration of strain reversal in strained SOI by the incorporation of SiGe in a short-channel PFET device. With regard to performance, at 0.75V the devices achieved a competitive effective drive current of 340 µA/µm for NFET at Ioff=1 nA/um (the highest performing FD-SOI NFET ever reported), and with a fully compressively strained 30% SiGe-on-insulator (SGOI) channel on a thin (20nm) BOX substrate, PFET effective drive current was 260 µA/µm at Ioff=1 nA/um. Competitive sub-threshold slope and DIBL are also reported.


[13] and [14] are Intel papers on 22nm bulk FinFET. [15] is TSMC on 16nm bulk FinFET. [9] is Leti et al on 14nm FD-SOI. “This work” pertains to the 10nm FD-SOI process presented by ST et al at IEDM ‘14. (Courtesy: ST et al, IEDM 2014)

[13] and [14] are Intel papers on 22nm bulk FinFET. [15] is TSMC on 16nm bulk FinFET. [9] is Leti et al on 14nm FD-SOI. “This work” pertains to the 10nm FD-SOI process presented by ST et al at IEDM ‘14.
(Courtesy: ST et al, IEDM 2014)

7.2: A Mobility Enhancement Strategy for sub-14nm Power-efficient FDSOI Technologies

B. De Salvo et al. (Leti, ST, IMEP, IBM, Soitec)

This paper presents an original multi-level evaluation methodology for stress engineering device design of next-generation power-efficient devices. Ring oscillator simulations showed that a dynamic power gain of 50% could be achieved while maintaining circuit frequency performance thanks to the use of efficient mobility boosters. Thus a clear scaling path to achieve high-mobility, power-efficient sub-14nm FDSOI technologies has been identified.


3.4: Single-P-Well SRAM Dynamic Characterization with Back-Bias Adjustment for Optimized Wide-Voltage Range SRAM Operation in 28nm UTBB FD-SOI

O. Thomas et al (UC Berkeley, ST)

This paper demonstrates the 28nm ultra-thin body and buried oxide (UTBB) FD-SOI high-density (0.120µm²) single pwell (SPW) bitcell architecture for the design of low-power wide voltage range systems enabled by back-bias adjustment. A 410mV minimum operating voltage and less than 310mV data retention voltage with less than 100fA/bitcell are measured in a 140kb programmable dynamic SRAM. Improved bitcell read access time and write-ability through back-bias are demonstrated with less than 5% of stand-by power overhead.


27.5: New Insights on Bottom Layer Thermal Stability and Laser Annealing Promises for High Performance 3D Monolithic Integration

C. Fenouillet-Beranger et al (Leti, ST, LASSE)

For the first time the maximum thermal budget of in-situ doped source/drain state-of-the-art FD-SOI bottom MOSFET transistors is quantified to ensure transistors stability in Monolithic 3D (M3D) integration. Thanks to silicide stability improvement, the top MOSFET temperature could be relaxed up to 500°C. Laser anneal is then considered as a promising candidate for junctions activation. Thanks to in-depth morphological and electrical characterizations, it shows very promising results for high performance Monolithic 3D integration.


9.2 Future Challenges and opportunities for Heterogeneous process technology. Toward the thin films, Zero intrinsic Variabiliiy devices, Zero power Era (Invited)

S. Deleonibus et al (Leti)

By 2025, 25 % of the World Gross Domestic Product will depend on the development of Information and Communication Technologies . Less greedy device, interconnect, computing technologies and architectures are essential to aim at x1000 less power consumption.

IBM’s SOI-FinFET, eDRAM and 3D Papers

32.1: Electrical Characterization of FinFET with Fins Formed by Directed Self Assembly at 29 nm Fin Pitch Using a Self-Aligned Fin Customization Scheme

H. Tsai et al (IBM)

These drawings illustrate the process flow for forming groups of SOI fins using the directed self-assembly technique. (IBM at IEDM ’14, paper 32.1)

These drawings illustrate the process flow for forming groups of SOI fins using the directed self-assembly technique. (IBM at IEDM ’14, paper 32.1)

High density fin formation is one of the most critical processes in the FinFET device fabrication flow. Given that a typical device is composed of an ensemble of fins, each fin must be nearly identical to avoid performance degradation arising from geometric variation. Thus, techniques for fin patterning must demonstrate the ability to form fins with a high degree of structural precision. In this paper, IBM researchers present the use of directed self-assembly using block copolymers (BCP) and 193nm immersion (193i) lithography as a suitable way to make the fins of FinFETs for beyond the 10 nm node.

(a) Shows groups of two fins formed by the process, while (b) is a cross-sectional image of a larger group of fins. (IBM at IEDM ’14, paper 32.1)

(a) Shows groups of two fins formed by the process, while (b) is a cross-sectional image of a larger group of fins. (IBM at IEDM ’14, paper 32.1)


Essentially, a topographic template pattern was created on a chemically neutral surface. Confinement of the BCP between the sidewalls of the template provides an ordering force that drives the pattern into registry with the surface topography. Electrical data produced from fins with a 29-nm pitch patterned with this approach showed good uniformity, with no signs of gross variation in critical dimensions.

Fabrication of FinFET devices using the self-assembly process (a) before customization; (b) after customization; (c) after gate patterning; and (d) after spacer formation and epitaxial Si growth. (IBM at IEDM ’14, paper 32.1)

Fabrication of FinFET devices using the self-assembly process (a) before customization; (b) after customization; (c) after gate patterning; and (d) after spacer formation and epitaxial Si growth. (IBM at IEDM ’14, paper 32.1)


3.8 High Performance 14nm SOI FinFET CMOS Technology with 0.0174μm2 embedded DRAM and 15 Levels of Cu Metallization (Late News)

C-H. Lin et al (IBM)

The IBM team presents a fully integrated 14nm CMOS technology featuring FinFET architecture on an SOI substrate for a diverse set of SoC applications including high-performance server microprocessors and low-power ASICs. A unique dual workfunction process optimizes the threshold voltages of both NMOS and PMOS transistors without any mobility degradation in the channel and without reliance on problematic approaches like heavy doping or Lgate modulation to create Vt differentiation. The IBM technology features what may be the smallest, densest embedded DRAM memory ever demonstrated (a cell size of just 0.0174µm2) for high-speed performance in a fully integrated process flow. Because the technology is envisioned for use in SoC applications ranging from video game consoles to enterprise-level corporate data centers, the IBM design also features a record 15 levels of copper interconnect to give circuit designers more freedom than ever before to distribute power and clock signals efficiently across an entire SoC chip, which may be as large as 600mm2.

The SOI FinFET’s excellent subthreshold behavior allows gate length scaling to the sub 20nm regime and superior low Vdd operation. This leads to a substantial (>35%) performance gain for Vdd ~0.8V compared to the HP 22nm planar predecessor technology. At the same time, the exceptional FE/BE reliability enables high Vdd (>1.1V) operation essential to the high single thread performance for processors intended for ‘scale-up’ enterprise systems. A hierarchical BEOL with 15 levels of copper interconnect delivers both high performance wire-ability as well as effective power supply and clock distribution for very large >600mm2 SoCs.


16.1: First Demonstration of High-Ge-Content Strained-Si1-xGex (x=0.5) on Insulator PMOS FinFETs with High Hole Mobility and Aggressively Scaled Fin Dimensions and Gate Lengths for High-Performance Applications

P. Hashemi et al (IBM)

Strained SiGe FinFETs are a promising PMOS technology for the 10nm technology node and beyond, due to their excellent electrostatics and built-in uniaxial compression. Yet while SiGe FinFETs with moderate germanium (Ge) content have been characterized, little data exists on FinFETs with high Ge  content. And, what little data does exist is mostly focused on relaxed or strained pure Ge. For the first time anywhere, IBM detailed CMOS-compatible, low-power and high-performance SiGe PMOS FinFETs with more than 50% Ge content. The devices feature ultra-narrow fin widths – down to 3.3 nm – which provide excellent short-channel control for low-power applications.  Using a Si-cap-free passivation process, they report SS=68mV/dec and μeff=390±12 cm2/Vs at Ninv=1e13 cm-2, outperforming the state-of-the-art relaxed Ge FinFETs. They demonstrated the highest performance ever reported (Ion=0.42mA/µm and Ioff=100nA/µm) for sub-20nm PMOS FinFETs at 0.5 V.


19.4: 0.026µm2 High Performance Embedded DRAM in 22nm Technology for Server and SOC Applications

C. Pei et al (IBM)

This paper presents the industry’s smallest eDRAM based on IBM’s 22nm (partially depleted) SOI technology, which has been recently leveraged for IBM’s 12-core 649mm2 Server Processor POWER8™. It summarizes the n-band resistance innovations, and reports for the first time the asymmetric embedded stressor, cavity implant and through gate implant employed in 22nm eDRAM technology. The fully integrated 256Mb product array has demonstrated capability of 1.4ns cycle time, which is significantly faster than any other embedded DRAM.


14.6: Through Silicon Via (TSV) Effects on Devices in Close Proximity– the Role of Mobile Ion Penetration – Characterization and Mitigation

C. Kothandaraman et al (IBM)

The research team identified and studied a new interaction between TSV processes and devices in close proximity, different from mechanical stress. Detailed characterization via Triangular Voltage Sweep (TVS) and SIMS shows the role of mobile ion penetration from BEOL layers. They then presented an improved process, confirmed in test structures and DRAM.



18.4: Technology Pathfinders for Low Cost and Highly Integrated RF Front End Modules

C. Raynaud (Leti)

This paper highlights the challenges related to the increasing number of modes (GSM, WCDMA, LTE) and frequency bands in mobile devices. It describes the technology pathfinders to get cheaper highly integrated multimode multi–band RF Front End modules.


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This is the 1st post in a 3-part series. Part 2 (click here to  read it) of ASN’s IEDM ’14 coverage looks at papers covering SOI-based future device architectures.  Part 3 (click here to read it) covers SOI-based MEMS, NEMS, sensors and more.

Successful RF-SOI 2014 International Symposium Held in Shanghai

A very successful international workshop on RF-SOI was held in Shanghai earlier this fall.  Jointly organized by industry leaders, it brought together world-class players in RF to discuss the opportunities and challenges in rapid development of RF applications.Sponsors included the SOI Industry Consortium, the Chinese Academy of Sciences (CAS) / Shanghai Institute of Microsystem and Information Technology (SIMIT), Shanghai Industrial μTechnology Research Institute Co.,Ltd. (SITRI) and VeriSilicon.

The first talk, given by Dr. Xi Wang, Academician of CAS and Director General of SIMIT, covered China’s huge market prospects for RF applications. RF-SOI, he noted, is an area in which Shanghai Simgui Technology Co.,Ltd. ,  a spin-off company from SIMIT,  and French SOI wafer manufacturer Soitec are working closely to explore the market opportunities now. He also presented some of the latest research findings and the industry dynamics in this field.

Xi Wang, Academician and Director General of the Shanghai Institute of Microsystem and Information Technology (SIMIT) /Chinese Academy of Sciences (CAS) giving the first talk at the 2014 International RF-SOI Workshop.

Xi Wang, Academician and Director General of the Shanghai Institute of Microsystem and Information Technology (SIMIT) /Chinese Academy of Sciences (CAS) giving the first talk at the 2014 International RF-SOI Workshop.


Next, Handel Jones, CEO of IBS, gave a detailed analysis of the markets for smart phones and tablet PCs and other mobile consumer applications. These are strong drivers of the huge market opportunity and demand for chips based on RF-SOI technology. (Click here to view his presentation.)


(Courtesy: IBS)

(Courtesy: IBS)

This workshop also featured presentations by ST, GlobalFoundries and SMIC, as well as several important RF-SOI platform providers.

Mark Ireland, Vice President of Strategy and Business Development at the IBM Microelectronics Division, noted that that IBM first began offering RF-SOI manufacturing in 2006.  He explained the key role RF-SOI plays in redefining chips for mobile applications, where integration and performance are key. (Click here to view his presentation.)

Laura Formenti, Infrastructure and RF-SOI Business Unit Director at STMicroelectronics, gave a detailed analysis of RF-SOI. She covered the advantages of RF front-end integration and introduced ST’s H9SOI_FEM technology platform. (Click here to view her presentation.)

Paul Colestock, Sr. Director of Segment Marketing at GlobalFoundries shared specifics and the latest developments in the 130nm RF-SOI technology platform, UltraCMOS 10.


The room was full at the Shanghai RF-SOI Workshop 2014

The room was full at the Shanghai RF-SOI Workshop 2014


Herb Huang, Sr. Director Development, Technology R&D at SMIC, China’s largest foundry, addressed SOI in RF switches. He shared details on SOI NFETs for enhanced performance, and on CMOS MEMS RF filters. SOI CMOS will facilitate integration of switches (SW), power amplifiers (PA), envelope tracking (ET) and antenna tuning (AT) in SoCs. The foundry provides not only device-level processes but also support for high-performance system-in-package (SiP) solutions at the wafer level.

Professor Jean-Pierre Raskin of the Catholic University of Leuven (Belgium) and Bernard Aspar, General Manager of Soitec’s Communication & Power Business Unit presented detailed technical analyses of SOI substrates.  They covered the influence of substrates on RF signal integrity and the key role they play in improving RF performance thanks to the enhanced Signal Integrity (eSI™) High Resistivity SOI substrate.  (Click here to view the UCL presentation, and here to view the Soitec presentation.)

James Young, VP of Engineering, FES Si Platform Engineering at Skyworks focused on RF and wireless semiconductor design. In particular he addressed mobile phone design, including PA, ET and APT (Average Power Tracking). He gave performance comparisons and analysis for SOI/CMOS vs. GaAs devices.  (Click here to view the presentation.)

Dr. Yumin Lu, VP of the Shanghai Industrial μTechnology Research Institute Co.,Ltd. elaborated on how 4G wireless communications brings new challenges for RF front-end modules and components. RF-SOI has become a mainstream technology for antenna/switches. There is also significant potential for RF-SOI to make further inroads in applications such as tunable components (including antennas, PAs, filters/duplexers, etc.). (Click here to view the presentation.)


Roundtable Discussion at the 2014 International RF-SOI Workshop in Shanghai

The final panel discussion session on the “China RF market” started a lively debate. Topics included the specificities and drivers of the China RF market, Chinese foundry capacity, the RF-SOI supply chain, RF front-end module (FEM) system packaging and system integration trends, and LTE and WiFi common platforms on RF-SOI substrates.  Audience members had questions about device design. The need for the industry to establish a broader ecosystem was a common theme.

 ~ ~ ~

Editor’s note: This article was first posted in Chinese at Shanghai Institute of Micro-Technology Industry Views. You can see the original hereMany thanks to Xi Wang, Academician and Director General of the Shanghai Institute of Microsystem and Information Technology (SIMIT) /Chinese Academy of Sciences (CAS) for his permission to translate/adapt and reprint it here in ASN.

Welcome to IEEE S3S – the World’s Leading Conference for SOI, 3DI and Sub Vt (SF, 6-9 Oct)


(For best rates, register by September 18th.)

The 2014 IEEE SOI-3DI–Subthreshold (S3S) Microelectronics Technology Unified Conference will take place from Monday October 6 through Thursday October 8 in San Francisco.

Photo Credit: Catherine Allibert

Photo Credit: Catherine Allibert

Last year we entered into a new era as the IEEE S3S Conference. The transition from the IEEE International SOI Conference to the IEEE S3S conference was successful by any measurement. The first year of the new conference leading-edge experts from 3D Integration, Sub-threshold Microelectronics and SOI fields gathered and we established a world class international venue to present, learn and debate about these exciting topics. The overall participation at the first year of the new conference grew by over 50%, and the overall quality and quantity of the technical content grew even more.

This year we are looking forward to continuing to enhance the content of the 2014 S3S Conference.


Short courses: Monolithic 3D & Power-Efficient Chip Tech

On Monday, Oct. 6 we will feature two Short Courses that will run in parallel. Short courses are an educational venue where newcomers can gain overview and generalists can learn more details about new and timely topics.

The short course on Monolithic 3D will be a full day deep dive into the topic of three-dimensional integration wherein the vertical connectivity is compatible with the horizontal connectivity (10,000x better than TSV). Already there are extremely successful examples of monolithic 3D Flash Memory. Looking beyond this initial application, we will explore the application of monolithic 3D to alternate memories like RRAM, CMOS systems with silicon and other channel materials like III V. In addition, a significant portion of the short course will be dedicated to the exciting opportunity of Monolithic 3D in the context of CMOS Logic.

The other short course we will offer this year is entitled Power Efficient Chip Technology. This short course will address several key aspects of power-efficiency including low power transistors and circuits. The course will also review in detail the impact of design and architecture on the energy-efficiency of systems. The short course chairs as well as the instructors are world class leading experts from the most prestigious industry and academic institutions.


Conference program

The regular conference sessions will start on Tuesday Oct. 7 with the plenary session, which will feature presentations from Wall Street (Morgan Stanley Investment Banking), Microsoft and MediaTek. After the plenary session we will hear invited talks and this year’s selection of outstanding papers from international researchers from top companies and universities. The most up to date results will be shared. Audience questions and one on one interaction with presenters is encouraged.

Back by popular demand we will have 2 Hot Topics Sessions this year. The first Hot Topic Session is scheduled for Tuesday Oct. 7th and will feature exciting 3DI topics. The other Hot Topics session is scheduled for Thursday Oct 9 and will showcase new and exciting work in the area of MEMS.

Our unique poster session and reception format will have a short presentation by the authors followed by one on one interaction to review details of the poster with the audience, in a friendly atmosphere, around a drink. Last year we had regular posters as well as several invited posters with very high quality content and we anticipate this year’s poster session to be even better than last years.

We are offering a choice of two different fundamentals classes on Wednesday afternoon. One of the Fundamentals classes will focus on Robust Design of Subthreshold Digital and Mixed Circuits, with tutorials by the worlds leading experts in this field. The SOI fundamentals course is focused on RF SOI Technology Fundamentals and Applications.

Our technical content is detailed on our program webpage.


Panel discussions, cookout & more

Keeping in line with tradition, on Wednesday night we will have a hearty cook out with delicious food and drink followed by the Panel Session entitled Cost and Benefit of Scaling Beyond 14nm. Panel speakers from financial, semiconductor equipment, technology, and academic research institutions will gather along with the audience to debate this timely topic. Although Thursday is the last day of the conference we will have stimulating presentations on novel devices, energy harvesting, radiation effects along with the MEMS Hot Topic Session and Late News Session. As always we will finish the conference with the award ceremony for the best papers.

SFstreetsignOur conference has a long tradition of attracting presenters and audience members from the most prestigious research, technology and academic institutions from around the world. There are many social events at the S3S Conference as well as quiet time where ideas are discussed and challenged off line and people from various fields can learn more about other fields of interest from leading experts.

The conference also offers many opportunities for networking with people inside and also outside ones area. The venue this year is San Francisco. We chose this location to attract the regions leading experts from Academia and Industry. If you have free time we encourage you to explore San Francisco which is famous for a multitude of cultural and culinary opportunities.

Please take a moment to learn more about our conference by browsing our website or downloading our advance program.

To take full advantage of this outstanding event, register before September 18!

Special hotel rates are also available from the dedicated hotel registration page.

The committee and I look forward to seeing you in San Fransisco.

– Bruce Doris, S3S General Chair

 Photo Credit: Catherine Allibert

Photo Credit: Catherine Allibert

imec 28 Gb/s photonics platform in upcoming multiproject SOI wafer runs

imec’s 28Gb/s silicon photonics platform for optical interconnects and other optical applications will be included in an upcoming multiproject wafer run, reports R. Colin Johnson in EETimes (read the article here). These runs, which are on SOI wafers, are a joint effort by ePIXfab (founded by imec and Leti), Europractice IC and MOSIS.  They provide a cost-effective vehicle for fabless researchers in data and telecom.