Jul 26, 2021

[paper] VNWFET Including Tied Compact Model

Arnaud Poittevin1, Chhandak Mukherjee2, Ian O’Connor1, Cristell Maneux2, Guilhem Larrieu3,4, Marina Deng2, Sebastien Le Beux1, Francois Marc2, Aurélie Lecestre3, Cedric Marchand1, 
and Abhishek Kumar3
3D Logic Cells Design and Results Based on Vertical NWFET Technology 
Including Tied Compact Model
In: Calimera A. (eds) VLSI-SoC: Design Trends. VLSI-SoC 2020. IFIP Advances in Information and Communication Technology, vol 621. pp 301-321 Springer, Cham.
DOI: 10.1007/978-3-030-81641-4_14

1 Lyon Institute of Nanotechnology, University of Lyon, France
2 University of Bordeaux, CNRS UMR 5218, Bordeaux INP Talence, Bordeaux, France
3 Université de Toulouse, LAAS, CNRS, INP Toulouse, Toulouse, France
4 Institute of Industrial Science, LIMMS-CNRS/IIS, The University of Tokyo, Japan


Abstract. Gate-all-around Vertical Nanowire Field Effect Transistors (VNWFET) are emerging devices, which are well suited to pursue scaling beyond lateral scaling limitations around 7 nm. This work explores the relative merits and drawbacks of the technology in the context of logic cell design. We describe a junctionless nanowire technology and associated compact model, which accurately describes fabricated device behavior in all regions of operations for transistors based on between 16 and 625 parallel nanowires of diameters between 22 and 50 nm. We used this model to simulate the projected performance of inverter logic gates based on passive load, active load and complementary topologies and to carry out a performance exploration for the number of nanowires in transistors. In terms of compactness, through a dedicated full 3D layout design, we also demonstrate a 48% reduction in lateral dimensions for the complementary structure with respect to 7 nm FinFET-based inverters.

Fig: Perspective view of the Gate-all-around Vertical Nanowire Field Effect Transistors (VNWFET)

Acknowledgments: This work was supported by the French RENATECH network (French national nanofabrication platform) and by the LEGO project through ANR funding (Grant ANR-18-CE24-0005-01).

[paper] NCFET CMOS Logic

Reinaldo Vega, Senior Member, IEEE, Takashi Ando*, Senior Member, IEEE,  
Timothy Philip, Member, IEEE
Junction Design and Complementary Capacitance Matching 
for NCFET CMOS Logic 
IEEE J-EDS 2021
DOI 10.1109/JEDS.2021.3095923

IBM Research, Albany, NY 12203
* IBM T.J. Watson Research Center, Yorktown Heights, NY 10598

Abstract: Negative capacitance field effect transistors (NCFETs) are modeled in this study, with an emphasis on junction design, implications of complementary logic, and device Vt menu enablement. Contrary to conventional MOSFET design, increased junction overlap is beneficial to NCFETs, provided the remnant polarization (Pr) is high enough. Combining broad junctions with complementary capacitance matching (CCM) in MFMIS (metal/ ferroelectric/ metal/ insulator/ semiconductor) NCFETs, it is shown that super-steep and non-hysteretic switching are not mutually exclusive, and that it is theoretically possible to achieve non-hysteretic sub-5 mV/dec SS over > 6 decades. In a CMOS circuit, due to CCM, low-Vt pairs provide steeper subthreshold swing (SS) than high-Vt pairs. Transient power/performance is also modeled, and it is shown that a DC optimal NCFET design, employing broad junctions, CCM, and a low-Vt NFET/PFET pair, does not translate to improved AC power/performance in unloaded circuits compared to a conventional FET reference. It is also shown that the same non-hysteretic DC design point is hysteretic in AC and may also lead to full polarization switching at higher voltages. Thus, a usable voltage window for AC NCFET operation forces a retreat from the DC-optimal design point.

Fig: Equivalent capacitance network and illustrative C-V curve showing NMOS and NC curves. CNC > CINV results in non-hysteretic switching, but low voltage gain in the off-state due to CNC >> COV. Setting CNC to CNC2, which is matched more closely to COV, results in very low SS, but also hysteretic switching as CNC2 < CINV. 

Acknowledgment: The authors would like to thank Paul Solomon and Prof. Sayeef Salahuddin for insightful discussions, as well as Synopsys for technical support.




Jul 21, 2021

[Final Program] 18th MOS-AK ESSDERC/ESSCIRC Workshop Grenoble; Sept. 6, 2021

MOS-AK ESSDERC/ESSCIRC Workshop Grenoble
Arbeitskreis Modellierung von Systemen und Parameterextraktion
Modeling of Systems and Parameter Extraction Working Group
18th MOS-AK ESSDERC/ESSCIRC Workshop
Grenoble, Sept. 6, 2021

Together with local Host and MOS-AK Organizers as well as all the Extended MOS-AK TPC Committee, we invite you to the consecutive 18th MOS-AK ESSDERC/ESSCIRC Workshop. Scheduled Virtual/Online MOS-AK event aims to strengthen a network and discussion forum among experts in the field, enhance open platform for information exchange related to compact/SPICE modeling and Verilog-A standardization, bring people in the compact modeling field together, as well as obtain feedback from technology developers, circuit designers, and TCAD/EDA tool developers and vendors.

The MOS-AK Workshop Program is available online: 

Venue: Online MOS-AK Webinar;
use the online form/link below to register.

Online Registration is open
any related enquiries can be sent to registration@mos-ak.org

Post-workshop publications, selected, the best papers will be recommended for further publication in the special compact/SPICE modeling issue of the Solid State Electronics.

-- W.Grabinski; MOS-AK (EU)

Enabling Compact Modeling R&D Exchange

WG210721

[paper] Compact Analytical Modeling of FD Dual Material DG MOSFET

Shahana Akter1, Md. Mirazur Rahman1 and Md. Arif Abdulla Samy2
Compact Analytical Modeling of Surface Potential 
of a fully depleted Dual Material Double Gate MOSFET
Materials Mechatronics and Systems Engineering 2021, 1, 1. https://citescript.com/Journals/index.php/mmsj/

1 Department of EEE, Primeasia University
2 ATLAS Experiment, CERN

Abstract: Scaling transistors to gain speed while reducing capacitance and cost, is a key topic of today’s semiconductor industry, which is widely affected by Short-Channel Effects, the phenomenon that reduces efficiency. To dominate that unwanted effect, a 2-dimensional electrostatic potential modeling of the fully depleted channel, with high-k based dual material double gate (DMDG) MOSFET, has been developed in this paper. The expression for the electrostatic potential of DMDG has beendeveloped using 2-D Poisson’s equation with appropriate device boundary conditions. The device performance has been analyzed with the variation in device parameters, such as channel length, channel thickness, oxide thickness, and other key parameters. For authenticating, results have also been compared with state-of-the-art published results. This research was successful to exhibit that the proposed model could overcome Drain-induced Barrier Lowering, enhancing mobility carrier resulting to optimize short channel effect, which can bring a revolutionary change in transistor industry as well as in low power VLSI applications.
Fig: Device structure for the 2D double gate MOSFET

Acknowledgment: Authors would like to thank Professor Dr. Quazi Deen Mohd Khosru for his guidance in every step of this research. Without his valuable and persistent help, it would not be possible to conclude this project. The project has no external funding.

[paper] 11.8 GHz Fin Resonant Body Transistor

Analysis and Modeling of an 11.8 GHz Fin Resonant Body Transistor 
in a 14nm FinFET CMOS Process 
Udit Rawat, Student Member, IEEE, Bichoy Bahr*, Member, IEEE, 
and Dana Weinstein, Senior Member, IEEE
arXiv:2107.04502v1 [physics.app-ph] 9 Jul 2021
 
Department of Electrical Engineering, Purdue University, West Lafayette USA
*Kilby Labs - Texas Instruments, Dallas, TX, USA.

Abstract: In this work, a compact model is presented for a 14 nm CMOS-based FinFET Resonant Body Transistor (fRBT) operating at a frequency of 11.8 GHz and targeting RF frequency generation/filtering for next generation radio communication, clocking, and sensing applications. Analysis of the phononic dispersion characteristics of the device, which informs the model development, shows the presence of polarization exchange due to the periodic nature of the back-end-of-line (BEOL) metal PnC. An eigenfrequency-based extraction process, applicable to resonators based on electrostatic force transduction, has been used to model the resonance cavity. Augmented forms of the BSIM-CMG (Common Multi-Gate) model for FinFETs are used to model the drive and sense transistors in the fRBT. This model framework allows easy integration with the foundry-supplied process design kits (PDKs) and circuit simulators while being flexible towards change in transduction mechanisms and device architecture. Ultimately, the behaviour is validated against RF measured data for the fabricated fRBT device under different operating conditions, leading to the demonstration of the first complete model for this class of resonant device integrated seamlessly in the CMOS stack.
Fig: Complete 3D FEM Simulation model depicting two adjoining fRBT unit cells. Mx (x=1-3) and Cy (y=4-6) represent the first 6 metal levels that form a part of the BEOL PnC.

Acknowledgement: This work was supported in part by the DARPA MIDAS Program.