12 documents found, page 1 of 2
Hard way or hardware? Taking the heat out of AI
Jayakrishnan, Ampattu R.; Hellenbrand, Markus; Dixon, Sebastian; Mehonic, Adnan; Silva, José Pedro Basto; MacManus-Driscoll, Judith L.The flurry of news worldwide surrounding the launch of DeepSeek’s artificial intelligence (AI) tool, operating at ∼5% of OpenAI’s GPT models, has drawn significant attention to global competitiveness in the AI field. Greater efficiency in software design to lower costs is of clear benefit to AI customers. It is also, however, critical to acknowledge the urgent need to sustain the otherwise continuous growth of ...
Coercive field control in epitaxial ferroelectric Hf0.5Zr0.5O2 thin films by na...
Kim, Ji Soo; Strkalj, Nives; Silva, Alexandre Daniel Mendonça Faria; Lenzi, Veniero; Marques, L.; Hill, Megan O.; Yuan, Ziyi; Liu, Yi XuanThe discovery of ferroelectric hafnium oxide has spurred great interest in the semiconductor industry, enabled by its complementary metal-oxide-semiconductor compatibility and scalability. However, many questions remain regarding the origin of the ferroelectric phases and the tunability of ferroelectric properties. In this work, we explore the influence of laser fluence on coercive field (E<inf>c</inf>) in 10 n...
Ultra-sensitive, self-powered, CMOS-compatible near-infrared photodetectors for...
Silva, Nuno E.; Jayakrishnan, Ampattu R.; Kaim, Adrian; Gwozdz, Katarzyna; Domingues, Leonardo; Kim, J. S.; Istrate, Marian C.; Ghica, CorneliuSelf-powered near-infrared (NIR) photodetectors are essential for surveillance systems, sensing in IoT electronics, facial recognition, health monitoring, optical communication networks, night vision, and biomedical imaging. However, silicon commercial detectors need external power to operate and cooling to suppress large dark currents. This work demonstrates a new class of CMOS-compatible self-powered NIR phot...
Growth of emergent simple pseudo-binary ferroelectrics and their potential in n...
Ravikumar, Jayakrishnan AMpattu; Kim, Ji S.; Hellenbrand, Markus; Marques, L.; MacManus-Driscoll, Judith L.; Silva, José Pedro BastoFerroelectric memory devices such as ferroelectric memristors, ferroelectric tunnel junctions, and field-effect transistors are considered among the most promising candidates for neuromorphic computing devices. The promise arises from their defect-independent switching mechanism, low energy consumption and high power efficiency, and important properties being aimed for are reliable switching at high speed, exce...
The benefits of incorporating lead-free ferroelectric materials in high energy ...
Jayakrishnan, Ampattu R.; Isfahani, Vahideh B.; Nair, Surya Kiran P.; Sekhar, Koppole C.; Marques, L.; Pereira, Mario; MacManus-Driscoll, Judith L.Demand for energy storage is increasing day by day and developing a pollution free environment necessitates new battery technologies. However, the existing energy storage technologies like lithium (Li)-ion batteries cannot fulfil the future needs alone. In this regard, Li-free batteries such as sodium (Na), potassium (K), zinc (Zn) and magnesium (Mg) ion batteries have attracted significant attention due to the...
Large ferro–pyro–phototronic effect in 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 ...
Silva, José Pedro Basto; Gwozdz, Katarzyna; Marques, Luís S.; Pereira, Mário; Gomes, M. J. M.; MacManus-Driscoll, Judith L.; Hoye, Robert L. Z.Coupling together the ferroelectric, pyroelectric, and photovoltaic characteristics within a single material is a novel way to improve the performance of photodetectors. In this work, we take advantage of the triple multifunctionality shown by 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BCZT), as demonstrated in an Al/Si/SiOx/BCZT/ITO thin-film device. The Si/SiOx acts as an n-type layer to form a metal–ferroelect...
The ferro-pyro-phototronic effect for high-performance self-powered photodetectors
Jayakrishnan, Ampattu Ravikumar; Silva, José Pedro Basto; Gwozdz, Katarzyna; Gomes, M. J. M.; Hoye, Robert L.Z.; MacManus-Driscoll, Judith L.Self-powered photodetectors are advantageous over conventional photodetectors because they can have outstanding performance in the absence of an external power source, which is important for a range of applications, including in the Internet of Things. Current research has demonstrated different types of self-powered photodetectors utilizing the photovoltaic effect, pyroelectric effect, piezoelectric effect, an...
Ferroelectric orthorhombic ZrO2 thin films achieved through nanosecond laser an...
Crema, Anna P. S.; Istrate, Marian C.; Silva, Alexandre; Lenzi, Veniero; Domingues, Leonardo; Hill, Megan O.; Teodorescu, Valentin S.; Ghica, CorneliuA new approach for the stabilization of the ferroelectric orthorhombic ZrO2 films is demonstrated through nanosecond laser annealing (NLA) of as-deposited Si/SiOx/W(14 nm)/ZrO2(8 nm)/W(22 nm), grown by ion beam sputtering at low temperatures. The NLA process optimization is guided by COMSOL multiphysics simulations. The films annealed under the optimized conditions reveal the presence of the orthorhombic phase,...
Ferroelectricity induced by oxygen vacancies in rhombohedral ZrO2 thin films
Lenzi, Veniero; Silva, José Pedro Basto; Šmíd, Břetislav; Matolín, Vladimir; Istrate, Cosmin M.; Ghica, Corneliu; MacManus-Driscoll, Judith L.Rhombohedral phase HfxZr1-xO2 (HZO, x from 0 to 1) films are promising for achieving robust ferroelectric polarisation without the need for an initial wake-up pre-cycling, as is normally the case for the more commonly studied orthorhombic phase. However, a large spontaneous polarisation observed in rhombohedral films is not fully understood, and there are also large discrepancies between experimental and theore...
Ferroelectricity and negative piezoelectric coefficient in orthorhombic phase p...
Silva, José Pedro Basto; Istrate, Marian C.; Hellenbrand, Markus; Jan, Atif; Becker, Maximilian T.; Symonowicz, Joanna; Figueiras, Fábio G.A new approach for epitaxial stabilisation of ferroelectric orthorhombic (o-) ZrO2 films with negative piezoelectric coefficient in ∼ 8nm thick films grown by ion-beam sputtering is demonstrated. Films on (011)-Nb:SrTiO3 gave the oriented o-phase, as confirmed by transmission electron microscopy and electron backscatter diffraction mapping, grazing incidence x-ray diffraction and Raman spectroscopy. Scanning pr...