Tag Archive M3D

ByFanny Rodriguez

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.

ByGianni PRATA

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.


IEEE SOI-3D-Subthreshold Conference (S3S, Oct. Sonoma, CA) Welcoming Papers til mid-May

Bacchus Entry

The IEEE SOI-3D-Subthreshold Microelectronics Technology Unified Conference (IEEE S3S) will be held in Sonoma Valley, CA 5-8 October 2015. (Photo courtesy: The DoubleTree by Hilton Sonoma Wine Country)

The IEEE SOI-3D-Subthreshold Microelectronics Technology Unified Conference (IEEE S3S) is welcoming papers until May 18, 2015.

Last year, the second edition of the IEEE S3S conference, founded upon the co-location of the IEEE International SOI Conference and the IEEE Subthreshold Microelectronics Conference was a great success targetting key topics and attracting even more participants than in 2013.

EDS Logo PMS3015_revu_smallThe conference will, this year again, hold two parallel sessions related to SOI and Subthreshold Microelectronics supplemented by a common session on 3D integration.

sponsor-ieeeWhile paper submissions are still accepted, the 2015 edition of the conference already promises a rich content of high-level presentations.


Geoffrey Yeap from Qualcomm will open the plenary session. He will give us a broad overview of the Ultra-Low Power SoC technologies.

Invited speakers from major industries (Intel, On Semiconductor, ST, Freescale, NXP, Soitec and more) and from many prestigious academic institutions will share with us their views of the ongoing technical challenges related to SOI, Sub-VT and 3D integration.

There will be two short courses again this year: One on SOI Application, and the other on Monolithic 3D.

Welcome to Doubletree Hotel Sonoma Wine Country

(Photo courtesy: The DoubleTree by Hilton Sonoma Wine Country)

There will also be a class on Logic devices for 28nm and beyond as well as a fundamentals class on Robust Subthreshold Ultra-low-voltage Design of Digital and Analog/RF Circuits.

The Hot Topics session will, this year, be about Ultra-Low Power.

During the Rump session we will debate about the What does IoT mean for semiconductor technology?

Scope of the conference:

The Committee will review papers submitted by May 18 in the three following focus areas of the conference:


Silicon On Insulator (SOI): Ever increasing demand and advances in SOI and related technologies make it essential to meet and discuss new gains and accomplishments in the field. For over 35 years our conference has been the premier meeting of engineers and scientists dedicated to current trends in Silicon-On-Insulator technology. Previously unpublished papers are solicited in all areas of SOI technology and related devices, circuits and applications.


Subthreshold Microelectronics: Ultra-low-power microelectronics will expand the technological capability of handheld and wireless devices by dramatically improving battery life and portability. Ubiquitous sensor networks, RFID tags, implanted medical devices, portable biosensors, handheld devices, and space-based applications are among those that would benefit from extremely low power circuits. One of the most promising methods of achieving ultra-low-power microelectronics is to reduce the operating voltage to below the transistor threshold voltage, which can result in energy savings of more than 90% compared to conventional low-power microelectronics. Papers describing original research and concepts in any subject of ultra-low-power microelectronics will be considered.


3D Integration, including monolithic 3D IC or sequential 3D IC, allows us to scale Integrated Circuits “orthogonally” in addition to classical 2D device and interconnect scaling. This session will address the unique features of such stacking with special emphasis on wafer level bonding as a reliable and cost effective method, similar to the creation of SOI wafers. We will cover fabrication techniques, bonding methods as well as design and test methodologies. Novel inter-strata interconnect schemes will also be discussed. Previously unpublished papers are solicited in all of the above areas related to 3D implementation.

Students are encouraged to submit papers and compete for the Best Student paper awards. Details on paper submission are given on the call for papers webpage.

Important dates:

Paper submission deadline: 18 May, 2015

Notification of acceptance: 07 June, 2015

Short course date: 5 October, 2015

Conference date: 5 – 8 October, 2015

More details are available on the S3S website.

ByGianni PRATA

Leti’s M3D, now dubbed “CoolCube”, featured in EETimes

Leti's M3D technology is now called "CoolCube". (Courtesy: Leti, IEDM 2014)

Leti’s M3D technology is now called “CoolCube”. (Courtesy: Leti, IEDM 2014)

Leti’s monolithic 3D technology, which has now been dubbed “CoolCube”, was featured in a recent EETimes piece.  Entitled True 3D monolithic integration eliminates TSV dependence (click here to read it), the article covers a Leti paper presented during a 3D-VLSI workshop preceding IEDM ’14.  Leti’s Advanced CMOS lab manager Maud Vinet detailed the “cool” process in an FPGA, stacking a 14nm FD-SOI logic layer on top of a memory layer. It eliminates the need for TSVs, shrinks area by 55%, cut power in half and increases speed by 30%, effectively gaining a full node in terms of power and performance.


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.

ByGianni PRATA

SST article details Leti’s Monolithic 3D presentation at Semicon West ’14

An excellent article in SST details Leti’s monolithic 3D (M3D) technology, as presented at the SemiconWest 2014 Leti Day (read the full article here). Written by Brian Cronquest, MonolithIC 3D’s VP Technology & IP, the piece covers a presentation given by Olivier Faynot, Leti’s Device Department Director, about “monolithic 3D technology as the ‘solution for scaling’.” Cronquest puts the big picture in perspective, while providing plenty of technical information. He ends by reminding readers that this and other key work will be further detailed at the IEEE S3S Conference (S3S = SOI + 3D + Subthreshold Microelectronics) October 6-9, 2014 at the Westin San Francisco Airport (see the conference website here).