TY - JOUR AU - Baji, Zsófia AU - Pécz, Béla AU - Fogarassy, Zsolt AU - Szabó, Zoltán AU - Cora, Ildikó TI - Atomic layer deposited Fe-sulphide layers with pyrrhotite structure controlled by the deposition temperature JF - THIN SOLID FILMS J2 - THIN SOLID FILMS VL - in press PY - 2024 SN - 0040-6090 DO - 10.1016/j.tsf.2024.140267 UR - https://m2.mtmt.hu/api/publication/34714394 ID - 34714394 AB - Atomic layer deposition was used to grow epitaxial iron sulphide layers on α-Al2O3 substrates. According to the transmission electron microscopic measurements, these Fe-sulphide films had 1C pyrrhotite structure (Fe1-xS). In the case of pyrrhotite materials, both the magnetic and electric properties depend significantly on their iron content and on the ordering of iron vacancies. By tuning the parameters of the atomic layer deposition method, the structure of epitaxial pyrrhotite films could be controlled, thus the electronic properties of the Fe1-xS films could be influenced: At deposition temperatures below 350°C, the structure contained many faults, and the layers were n type semiconductors, while at higher temperatures, the resulting films were p-type with excellent crystalline structures with disordered vacancies. A post deposition annealing could further improve the crystallinity and induce p-type conductivity. LA - English DB - MTMT ER - TY - JOUR AU - Biró, László Péter AU - Pécz, Béla TI - Gyulai József öröksége a funkcionális anyagok tudományában JF - FIZIKAI SZEMLE J2 - FIZIKAI SZEMLE VL - 74 PY - 2024 IS - 3 SP - 73 EP - 73 PG - 1 SN - 0015-3257 UR - https://m2.mtmt.hu/api/publication/34727537 ID - 34727537 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Galizia, Bruno AU - Fiorenza, Patrick AU - Schilirò, Emanuela AU - Pécz, Béla AU - Fogarassy, Zsolt AU - Greco, Giuseppe AU - Saggio, Mario AU - Cascino, Salvatore AU - Lo, Nigro Raffaella AU - Roccaforte, Fabrizio TI - Towards aluminum oxide/aluminum nitride insulating stacks on 4H–SiC by atomic layer deposition JF - MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING J2 - MAT SCI SEMICON PROC VL - 174 PY - 2024 PG - 7 SN - 1369-8001 DO - 10.1016/j.mssp.2024.108244 UR - https://m2.mtmt.hu/api/publication/34653875 ID - 34653875 AB - Stacked aluminum oxide/aluminum nitride (Al2O3/AlN) layers were deposited on n-type (0001) 4H–SiC by atomic layer deposition (ALD) processes. The structural and chemical properties have been investigated and are consistent with the growth of ∼9 nm oriented (0001) AlN layer, and an upper 20 nm amorphous Al2O3 layer. The entire Al2O3/AlN stack was electrically characterized and compared with respect to a single Al2O3 layer having the same total thickness. The Al2O3/AlN bilayer exhibited a higher dielectric constant (κ = 8.7), a significant reduction of the oxide trapped charges (NOT) from 7.8 × 1012 to 1.8 × 1012 cm−2, as well as a decrease of a factor 2 of the interface traps density (Dit) compared with the Al2O3 single layer values. A large positive flat band voltage shift was observed in the C–V curves acquired on MIS capacitors. The comparison of the behaviour of MIS capacitors fabricated on both n-type and p-type 4H–SiC demonstrated that deep interface states (near the 4H–SiC mid gap) acting as acceptors or donors for the n-type and p-type MIS contribute to the observed behavior. This hypothesis has been also corroborated by TCAD simulations. LA - English DB - MTMT ER - TY - JOUR AU - Galizia, Bruno AU - Fiorenza, Patrick AU - Bongiorno, Corrado AU - Pécz, Béla AU - Fogarassy, Zsolt AU - Schilirò, Emanuela AU - Giannazzo, Filippo AU - Roccaforte, Fabrizio AU - Nigro, Raffaella Lo TI - Structural and electrical correlation in aluminum nitride thin films grown by plasma enhanced atomic layer deposition as interface insulating layers on silicon carbide (4H-SiC) JF - MICROELECTRONIC ENGINEERING J2 - MICROELECTRON ENG VL - 283 PY - 2024 PG - 7 SN - 0167-9317 DO - 10.1016/j.mee.2023.112103 UR - https://m2.mtmt.hu/api/publication/34193521 ID - 34193521 LA - English DB - MTMT ER - TY - JOUR AU - Giannazzo, Filippo AU - Panasci, Salvatore Ethan AU - Schilirò, Emanuela AU - Koós, Antal Adolf AU - Pécz, Béla TI - Integration of graphene and MoS2 on silicon carbide: Materials science challenges and novel devices JF - MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING J2 - MAT SCI SEMICON PROC VL - 174 PY - 2024 PG - 13 SN - 1369-8001 DO - 10.1016/j.mssp.2024.108220 UR - https://m2.mtmt.hu/api/publication/34571541 ID - 34571541 AB - Although silicon carbide (SiC) is widely regarded as the material of choice for power electronics, the development of several new applications on the SiC material platform is currently explored. The integration of two dimensional (2D) materials, such as graphene and molybdenum disulfide (MoS2) provides silicon carbide (SiC) with additional functionalities, allowing to expand its range of applications. This article reviews the state-of-the art methods for scalable growth of graphene and MoS2 on SiC, specifically on the hexagonal polytypes. Some open research directions in materials integration have been also discussed, like the use of epitaxial graphene (Epi-Gr) as interlayer for van der Waals (vdW) epitaxy of GaN or Ga2O3 on SiC substrates, and the growth of 2D forms of GaN materials by confined epitaxy at Epi-Gr/SiC interface. Finally, an overview of recently proposed electronics/optoelectronics applications of these material systems, specifically for high frequency electronics, quantum metrology, THz and UV detectors, is provided. This work can be a useful guide for silicon carbide community on these open research directions. LA - English DB - MTMT ER - TY - JOUR AU - Lábár, János AU - Pécz, Béla TI - Transzmissziós elektronmikroszkópia az MFA-ban JF - FIZIKAI SZEMLE J2 - FIZIKAI SZEMLE VL - 74 PY - 2024 IS - 3 SP - 84 EP - 87 PG - 4 SN - 0015-3257 UR - https://m2.mtmt.hu/api/publication/34727542 ID - 34727542 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Panasci, Salvatore E. AU - Deretzis, Ioannis AU - Schilirò, Emanuela AU - La, Magna Antonino AU - Roccaforte, Fabrizio AU - Koós, Antal Adolf AU - Nemeth, Miklos AU - Pécz, Béla AU - Cannas, Marco AU - Agnello, Simonpietro AU - Giannazzo, Filippo TI - Interface Properties of MoS2 van der Waals Heterojunctions with GaN JF - NANOMATERIALS J2 - NANOMATERIALS-BASEL VL - 14 PY - 2024 IS - 2 PG - 14 SN - 2079-4991 DO - 10.3390/nano14020133 UR - https://m2.mtmt.hu/api/publication/34481837 ID - 34481837 AB - The combination of the unique physical properties of molybdenum disulfide (MoS2) with those of gallium nitride (GaN) and related group-III nitride semiconductors have recently attracted increasing scientific interest for the realization of innovative electronic and optoelectronic devices. A deep understanding of MoS2/GaN interface properties represents the key to properly tailor the electronic and optical behavior of devices based on this heterostructure. In this study, monolayer (1L) MoS2 was grown on GaN-on-sapphire substrates by chemical vapor deposition (CVD) at 700 °C. The structural, chemical, vibrational, and light emission properties of the MoS2/GaN heterostructure were investigated in detail by the combination of microscopic/spectroscopic techniques and ab initio calculations. XPS analyses on as-grown samples showed the formation of stoichiometric MoS2. According to micro-Raman spectroscopy, monolayer MoS2 domains on GaN exhibit an average n-type doping of (0.11 ± 0.12) × 1013 cm−2 and a small tensile strain (ε ≈ 0.25%), whereas an intense light emission at 1.87 eV was revealed by PL analyses. Furthermore, a gap at the interface was shown by cross-sectional TEM analysis, confirming the van der Waals (vdW) bond between MoS2 and GaN. Finally, density functional theory (DFT) calculations of the heterostructure were carried out, considering three different configurations of the interface, i.e., (i) an ideal Ga-terminated GaN surface, (ii) the passivation of Ga surface by a monolayer of oxygen (O), and (iii) the presence of an ultrathin Ga2O3 layer. This latter model predicts the formation of a vdW interface and a strong n-type doping of MoS2, in closer agreement with the experimental observations. LA - English DB - MTMT ER - TY - JOUR AU - Roccaforte, F. AU - Vivona, M. AU - Panasci, S.E. AU - Greco, G. AU - Fiorenza, P. AU - Sulyok, Attila AU - Koós, Antal Adolf AU - Pécz, Béla AU - Giannazzo, F. TI - Schottky contacts on sulfurized silicon carbide (4H-SiC) surface JF - APPLIED PHYSICS LETTERS J2 - APPL PHYS LETT VL - 124 PY - 2024 IS - 10 PG - 5 SN - 0003-6951 DO - 10.1063/5.0192691 UR - https://m2.mtmt.hu/api/publication/34773813 ID - 34773813 LA - English DB - MTMT ER - TY - JOUR AU - Cadena Nogales, Ana Cristina AU - Pekker, Áron AU - Botka, Bea AU - Dodony, Erzsébet AU - Fogarassy, Zsolt AU - Pécz, Béla AU - Kamarás, Katalin TI - Encapsulation of the Graphene Nanoribbon Precursor 1, 2, 4‐trichlorobenzene in Boron Nitride Nanotubes at Room Temperature JF - PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS J2 - PHYS STATUS SOLIDI-R VL - 17 PY - 2023 IS - 1 PG - 5 SN - 1862-6254 DO - 10.1002/pssr.202200284 UR - https://m2.mtmt.hu/api/publication/33138741 ID - 33138741 LA - English DB - MTMT ER - TY - JOUR AU - Dumas, P. AU - Opprecht, M. AU - Kerdilès, S. AU - Lábár, János AU - Pécz, Béla AU - Lefloch, F. AU - Nemouchi, F. TI - Superconductivity in laser-annealed monocrystalline silicon films: The role of boron implant JF - APPLIED PHYSICS LETTERS J2 - APPL PHYS LETT VL - 123 PY - 2023 IS - 13 PG - 10 SN - 0003-6951 DO - 10.1063/5.0166870 UR - https://m2.mtmt.hu/api/publication/34332659 ID - 34332659 LA - English DB - MTMT ER -