Publications by Carlotta Gastaldi

Ferroelectric Junctionless Double-Gate Silicon-On-Insulator FET as a Tripartite Synapse

Igor Stolichnov, Mihai Adrian Ionescu, Ali Saeidi, Matteo Cavalieri, Carlotta Gastaldi, Sadegh Kamaei Bahmaei

In this work, we report the concept and experimentally demonstrate the first tunable ferroelectric (Fe) junctionless (JL) transistor (Fe-JLFET), capable of emulating the functionality of biological tri-partite synapses, which is an artificial three-termina ...

Institute of Electrical and Electronics Engineers2023

Ferroelectric Supercapacitors by Combining Polarization Switching and Negative Capacitance Effects for On-Chip Energy Storage

Mihai Adrian Ionescu, Carlotta Gastaldi, Sadegh Kamaei Bahmaei, Ali Gilani, Michele Ghini

In this work, we investigate the fundamental effects contributing to energy storage enhancement in on-chip ferroelectric electrostatic supercapacitors with doped high-k dielectrics. By optimizing energy storage density and efficiency in nanometer-thin stac ...

Institute of Electrical and Electronics Engineers2023

Ferroelectric gating of two-dimensional semiconductors for the integration of steep-slope logic and neuromorphic devices

Mihai Adrian Ionescu, Jürgen Brugger, Ali Saeidi, Carlotta Gastaldi, Sadegh Kamaei Bahmaei, Xia Liu

The co-integration of logic switches and neuromorphic functions could be used to create new computing architectures with low power consumption and novel functionalities. Two-dimensional (2D) semiconductors and ferroelectric materials could be potentially u ...

NATURE PORTFOLIO2023

Zn/P ratio and microstructure defines carrier density and electrical transport mechanism in earth-abundant Zn3-xP2+y thin films

Mihai Adrian Ionescu, Anna Fontcuberta i Morral, Mahdi Zamani, Simon Robert Escobar Steinvall, Rajrupa Paul, Carlotta Gastaldi, Valerio Piazza, Mirjana Dimitrievska

Scalable and sustainable photovoltaic technologies require low-cost and earth-abundant semiconducting materials. Zinc phosphide is purported to be an absorber material with optimal photovoltaic properties. Herein we report the electrical properties of Zn3P ...

2023

Negative Capacitance in HfO2 Gate Stack Structures With and Without Metal Interlayer

Igor Stolichnov, Mihai Adrian Ionescu, Ali Saeidi, Francesco Bellando, Matteo Cavalieri, Eamon Patrick O'Connor, Carlotta Gastaldi

In this work, we experimentally explore and compare FET gate stacks with and without an inner metal plane between a linear dielectric (SiO2) and a ferroelectric layer (Si-doped HfO2) operating in the negative capacitance (NC) regime. The use of nanosecond- ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Fully integrated Si:HfO2 Negative Capacitance 2D-2D WSe2/SnSe2 Subthermionic Tunnel FETs

Mihai Adrian Ionescu, Jürgen Brugger, Clara-Fausta Moldovan, Ali Saeidi, Carlotta Gastaldi, Sadegh Kamaei Bahmaei, Xia Liu

We report the first experimental demonstration and performance characterization of a fully integrated negative capacitance (NC) WSe2/SnSe2 p-type Tunnel FETs (TFETs), validating the use of NC as a technology booster to achieve a significantly improved sub- ...

IEEE2022

Exploring negative capacitance and neuromorphic devices based on CMOS-compatible ferroelectric HfO2

Carlotta Gastaldi

Ferroelectric materials are explored for numerous applications thanks to their properties associated with electrically switchable spontaneous polarization. Perovskites are an established class of ferroelectrics used for sensors and actuators. However, they ...

EPFL2022

Intrinsic switching in Si-doped HfO2: A study of Curie-Weiss law and its implications for negative capacitance field-effect transistor

Igor Stolichnov, Mihai Adrian Ionescu, Teodor Rosca, Ali Saeidi, Matteo Cavalieri, Eamon Patrick O'Connor, Carlotta Gastaldi, Sadegh Kamaei Bahmaei

HfO2-based ferroelectrics are considered a promising class of materials for logic and memory applications due to their CMOS compatibility and ferroelectric figures of merit. A steep-slope field-effect-transistor (FET) switch is a device for logic applicati ...

AMER INST PHYSICS2021

Gate energy efficiency and negative capacitance in ferroelectric 2D/2D TFET from cryogenic to high temperatures

Mihai Adrian Ionescu, Teodor Rosca, Ali Saeidi, Matteo Cavalieri, Luca Capua, Carlotta Gastaldi, Sadegh Kamaei Bahmaei

We report the fabrication process and performance characterization of a fully integrated ferroelectric gate stack in a WSe2/SnSe2 Tunnel FETs (TFETs). The energy behavior of the gate stack during charging and discharging, together with the energy loss of a ...

NATURE PORTFOLIO2021

Intrinsic or nucleation-driven switching: An insight from nanoscopic analysis of negative capacitance Hf1-xZrxO2-based structures

Igor Stolichnov, Mihai Adrian Ionescu, Matteo Cavalieri, Carlotta Gastaldi

HfO2-based ferroelectrics have dramatically changed the application perspectives of polarization-switching materials for information processing and storage. Their CMOS compatibility and preservation of high reversible polarization down to a few nanometer t ...

AMER INST PHYSICS2020

Experimental Investigation of Pulsed Laser Deposition of Ferroelectric Gd:HfO2 in a CMOS BEOL Compatible Process

Igor Stolichnov, Mihai Adrian Ionescu, Matteo Cavalieri, Eamon Patrick O'Connor, Carlotta Gastaldi

In this work, we report an experimental investigation of pulsed laser deposition (PLD) of thin Gd:HfO2 layers at 330 degrees C, which show ferroelectric behavior after annealing at 450 degrees C, compatible with complementary metal-oxide-semiconductor back ...

AMER CHEMICAL SOC2020

Subthermionic negative capacitance ion sensitive field-effect transistor

Mihai Adrian Ionescu, Ali Saeidi, Francesco Bellando, Carlotta Gastaldi

One of the main advantages of Ion-Sensitive Field-Effect Transistor (ISFET) technology is the capability to exploit technological advancements initially developed for conventional FETs for logic applications, such as the employ of high-k dielectrics for th ...

2020

Transient Negative Capacitance of Silicon-doped HfO2 in MFMIS and MFIS structures: experimental insights for hysteresis-free steep slope NC FETs

Paul Muralt, Igor Stolichnov, Mihai Adrian Ionescu, Ali Saeidi, Matteo Cavalieri, Carlotta Gastaldi

In this paper, we experimentally explore the transient negative capacitance effect in ferroelectric high-k gate stacks using multi-ferroelectric domain Si-doped HfO2 with and without the metal plane, MFMIS (TiN/Si:HfO2/TiN/SiO2) and MFIS (TiN/Si:HfO2/SiO2) ...

IEEE2019