Articoli di riviste: "Hafnium oxide layers"

1

Neuber, Markus, Maximilian Walter Lederer, Konstantin Mertens, Thomas Kämpfe, Malte Czernohorsky e Konrad Seidel. "Pyroelectric and Ferroelectric Properties of Hafnium Oxide Doped with Si via Plasma Enhanced ALD". Crystals 12, n. 8 (9 agosto 2022): 1115. http://dx.doi.org/10.3390/cryst12081115.

Testo completo

Abstract (sommario):

Devices based on ferroelectric hafnium oxide are of major interest for sensor and memory applications. In particular, Si-doped hafnium oxide layers are investigated for the application in the front-end-of-line due to their resilience to high thermal treatments. Due to its very confined doping concentration range, Si:HfO2 layers based on thermal atomic layer deposition often exhibited a crossflow pattern across 300 mm wafer. Here, plasma enhanced atomic layer deposition is explored as an alternative method for producing Si-doped HfO2 layers, and their ferroelectric and pyroelectric properties are compared.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Borowicz, P., A. Taube, W. Rzodkiewicz, M. Latek e S. Gierałtowska. "Raman Spectra of High-κDielectric Layers Investigated with Micro-Raman Spectroscopy Comparison with Silicon Dioxide". Scientific World Journal 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/208081.

Testo completo

Abstract (sommario):

Three samples with dielectric layers from high-κdielectrics, hafnium oxide, gadolinium-silicon oxide, and lanthanum-lutetium oxide on silicon substrate were studied by Raman spectroscopy. The results obtained for high-κdielectrics were compared with spectra recorded for silicon dioxide. Raman spectra suggest the similarity of gadolinium-silicon oxide and lanthanum-lutetium oxide to the bulk nondensified silicon dioxide. The temperature treatment of hafnium oxide shows the evolution of the structure of this material. Raman spectra recorded foras-depositedhafnium oxide are similar to the results obtained for silicon dioxide layer. After thermal treatment especially at higher temperatures (600°C and above), the structure of hafnium oxide becomes similar to the bulk non-densified silicon dioxide.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Lederer, Maximilian, Tobias Vogel, Thomas Kämpfe, Nico Kaiser, Eszter Piros, Ricardo Olivo, Tarek Ali et al. "Heavy ion irradiation induced phase transitions and their impact on the switching behavior of ferroelectric hafnia". Journal of Applied Physics 132, n. 6 (14 agosto 2022): 064102. http://dx.doi.org/10.1063/5.0098953.

Testo completo

Abstract (sommario):

The discovery of ferroelectric hafnium oxide enabled a variety of non-volatile memory devices, like ferroelectric tunnel junctions or field-effect transistors. Reliable application of hafnium oxide based electronics in space or other high-dose environments requires an understanding of how these devices respond to highly ionizing radiation. Here, the effect of 1.6 GeV Au ion irradiation on these devices is explored, revealing a reversible phase transition, as well as a grain fragmentation process. The collected data demonstrate that non-volatile memory devices based on ferroelectric hafnia layers are ideal for applications where excellent radiation hardness is mandatory.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Kappa, Mathias, Markus Ratzke e Jürgen Reif. "Pulsed Laser Deposition of Hafnium Oxide on Silicon". Solid State Phenomena 108-109 (dicembre 2005): 723–28. http://dx.doi.org/10.4028/www.scientific.net/ssp.108-109.723.

Testo completo

Abstract (sommario):

Hafnium oxide films were prepared by Pulsed Laser Deposition (PLD). The influence of laser wavelength (fundamental, second and third harmonic of a Nd:YAG laser), used for evaporation, and substrate temperature on the film morphology, chemical structure and interfacial quality were investigated yielding the following results: While the laser wavelength exhibits minor influence on layer structure, the substrate temperature plays a critical role regarding morphological and chemical structure of the produced hafnium oxide / silicon stacks. Atomic Force Microscopy (AFM) images show a clear transition from smooth layers consisting of small area crystallites to very rough surfaces characterized by large craters and regular, plane features when the growth temperature was increased. These facts suggest a chemical instability which is confirmed by X-ray Photoelectron Spectroscopy (XPS). Investigations of the hafnium and silicon core level spectra indicate the occurrence of silicon dioxide and hafnium silicide in the case the samples were produced at elevated temperatures.

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Lederer, Maximilian, Konstantin Mertens, Ricardo Olivo, Kati Kühnel, David Lehninger, Tarek Ali, Thomas Kämpfe, Konrad Seidel e Lukas M. Eng. "Substrate-dependent differences in ferroelectric behavior and phase diagram of Si-doped hafnium oxide". Journal of Materials Research 36, n. 21 (2 novembre 2021): 4370–78. http://dx.doi.org/10.1557/s43578-021-00415-y.

Testo completo

Abstract (sommario):

Abstract Non-volatile memories based on ferroelectric hafnium oxide, especially the ferroelectric field-effect transistor (FeFET), have outstanding properties, e.g. for the application in neuromorphic circuits. However, material development has focused so far mainly on metal–ferroelectric–metal (MFM) capacitors, while FeFETs are based on metal–ferroelectric–insulator–semiconductor (MFIS) capacitors. Here, the influence of the interface properties, annealing temperature and Si-doping content are investigated. Antiferroelectric-like behavior is strongly suppressed with a thicker interface layer and high annealing temperature. In addition, high-k interface dielectrics allow for thicker interface layers without retention penalty. Moreover, the process window for ferroelectric behavior is much larger in MFIS capacitors compared to MFM-based films. This does not only highlight the substrate dependence of ferroelectric hafnium oxide films, but also gives evidence that the phase diagram of ferroelectric hafnium oxide is defined by the mechanical stress. Graphic Abstract

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Kahro, Tauno, Kristina Raudonen, Joonas Merisalu, Aivar Tarre, Peeter Ritslaid, Aarne Kasikov, Taivo Jõgiaas et al. "Nanostructures Stacked on Hafnium Oxide Films Interfacing Graphene and Silicon Oxide Layers as Resistive Switching Media". Nanomaterials 13, n. 8 (9 aprile 2023): 1323. http://dx.doi.org/10.3390/nano13081323.

Testo completo

Abstract (sommario):

SiO2 films were grown to thicknesses below 15 nm by ozone-assisted atomic layer deposition. The graphene was a chemical vapor deposited on copper foil and transferred wet-chemically to the SiO2 films. On the top of the graphene layer, either continuous HfO2 or SiO2 films were grown by plasma-assisted atomic layer deposition or by electron beam evaporation, respectively. Micro-Raman spectroscopy confirmed the integrity of the graphene after the deposition processes of both the HfO2 and SiO2. Stacked nanostructures with graphene layers intermediating the SiO2 and either the SiO2 or HfO2 insulator layers were devised as the resistive switching media between the top Ti and bottom TiN electrodes. The behavior of the devices was studied comparatively with and without graphene interlayers. The switching processes were attained in the devices supplied with graphene interlayers, whereas in the media consisting of the SiO2-HfO2 double layers only, the switching effect was not observed. In addition, the endurance characteristics were improved after the insertion of graphene between the wide band gap dielectric layers. Pre-annealing the Si/TiN/SiO2 substrates before transferring the graphene further improved the performance.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Pan, Yaru, Xihui Liang, Zhihao Liang, Rihui Yao, Honglong Ning, Jinyao Zhong, Nanhong Chen, Tian Qiu, Xiaoqin Wei e Junbiao Peng. "Application of Solution Method to Prepare High Performance Multicomponent Oxide Thin Films". Membranes 12, n. 7 (22 giugno 2022): 641. http://dx.doi.org/10.3390/membranes12070641.

Testo completo

Abstract (sommario):

Capacitors play an increasingly important role in hybrid integrated circuits, while the MIM capacitors with high capacitance density and small thickness can meet the needs of high integration. Generally speaking, the films prepared with a single metal oxide dielectric often achieve a breakthrough in one aspect of performance, but dielectric layers are required to be improved to get better performance in leakage current, capacitance density, and transmittance simultaneously in modern electronic devices. Therefore, we optimized the performance of the dielectric layers by using multiple metal oxides. We combined zirconia, yttria, magnesium oxide, alumina, and hafnium oxide with the solution method to find the best combination of these five metal oxides. The physical properties of the multi-component films were measured by atomic force microscopy (AFM), ultraviolet-visible spectrophotometer, and other instruments. The results show that the films prepared by multi-component metal oxides have good transmittance and low roughness. The thicknesses of all films in our experiment are less than 100 nm. Then, metal–insulator–metal (MIM) devices were fabricated. In addition, we characterized the electrical properties of MIM devices. We find that multi-component oxide films can achieve good performances in several aspects. The aluminum-magnesium-yttrium-zirconium-oxide (AMYZOx) group of 0.6 M has the lowest leakage current density, which is 5.03 × 10−8 A/cm2 @ 1.0 MV/cm. The hafnium-magnesium-yttrium-zirconium-oxide (HMYZOx) group of 0.8 M has a maximum capacitance density of 208 nF/cm2. The films with a small thickness and a high capacitance density are very conducive to high integration. Therefore, we believe that multi-component films have potential in the process of dielectric layers and great application prospects in highly integrated electronic devices.

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Ihlefeld, Jon F., Samantha T. Jaszewski e Shelby S. Fields. "A Perspective on ferroelectricity in hafnium oxide: Mechanisms and considerations regarding its stability and performance". Applied Physics Letters 121, n. 24 (12 dicembre 2022): 240502. http://dx.doi.org/10.1063/5.0129546.

Testo completo

Abstract (sommario):

Ferroelectric hafnium oxides are poised to impact a wide range of microelectronic applications owing to their superior thickness scaling of ferroelectric stability and compatibility with mainstream semiconductors and fabrication processes. For broad-scale impact, long-term performance and reliability of devices using hafnia will require knowledge of the phases present and how they vary with time and use. In this Perspective article, the importance of phases present on device performance is discussed, including the extent to which specific classes of devices can tolerate phase impurities. Following, the factors and mechanisms that are known to influence phase stability, including substituents, crystallite size, oxygen point defects, electrode chemistry, biaxial stress, and electrode capping layers, are highlighted. Discussions will focus on the importance of considering both neutral and charged oxygen vacancies as stabilizing agents, the limited biaxial strain imparted to a hafnia layer by adjacent electrodes, and the strong correlation of biaxial stress with resulting polarization response. Areas needing additional research, such as the necessity for a more quantitative means to distinguish the metastable tetragonal and orthorhombic phases, quantification of oxygen vacancies, and calculation of band structures, including defect energy levels for pure hafnia and stabilized with substituents, are emphasized.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Kim, Dae-Cheol, e Young-Geun Ha. "Self-Assembled Hybrid Gate Dielectrics for Ultralow Voltage of Organic Thin-Film Transistors". Journal of Nanoscience and Nanotechnology 21, n. 3 (1 marzo 2021): 1761–65. http://dx.doi.org/10.1166/jnn.2021.19083.

Testo completo

Abstract (sommario):

We developed self-assembled hybrid dielectric materials via a facile and low-temperature solution process. These dielectrics are used to facilitate ultralow operational voltage of organic thinfilm transistors. Self-assembly of bifunctional phosphonic acid and ultrathin hafnium oxide layers results in the self-assembled hybrid dielectrics. Additionally, the surface property of the top layer of hafnium oxide can be tuned by phosphonic acid-based self-assembled molecules to improve the function of the organic semiconductors. These novel hybrid dielectrics demonstrate great dielectric properties as low-level leakage current densities of <1.45×10−6 A/cm2, large capacitances (up to 800 nF/cm2), thermal stability (up to 300 °C), and featureless morphology (root-mean-square roughness ˜0.3 nm). As a result, self-assembled gate dielectrics can be incorporated into thin-film transistors with p-type organic semiconductors functioning at ultralow voltages (<-2 V) to achieve enhanced performance (hole mobility: 0.88 cm2/V·s, and Ion/Ioff: > 105, threshold voltage: 0.5 V).

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Dementev, P. A., e E. V. Dementeva. "Kelvin-probe microscopy as a technique of estimation of the charge traps saturation time". Journal of Physics: Conference Series 2103, n. 1 (1 novembre 2021): 012067. http://dx.doi.org/10.1088/1742-6596/2103/1/012067.

Testo completo

Abstract (sommario):

Abstract In this work, a method for estimating the saturation time of traps in dielectric layers based on the KPM is proposed. Using hafnium oxide layers as an example, it is shown that when charging with a series of points with different durations, a different dependence of the residual potential on time is observed. It is assumed that this technique makes it possible to evaluate the performance of devices based on dielectric layers.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Romanowska, Jolanta, Maryana Zagula-Yavorska e Łukasz Kolek. "Oxidation Resistance of Modified Aluminide Coatings". MATEC Web of Conferences 253 (2019): 03006. http://dx.doi.org/10.1051/matecconf/201925303006.

Testo completo

Abstract (sommario):

The application of protective aluminide coatings is an effective way to increase the oxidation resistance of the treated parts and prolongs their lifetime. The addition of small amount of noble metals (platinum or palladium) or reactive elements such as: hafnium, zirconium, yttrium and cerium has a beneficial effect on oxidation behavior. This beneficial effect includes an improvement of adhesion of alumina scales and reduction of oxide scale growth rate. Platinum and hafnium or zirconium modified aluminide coating were deposited on pure nickel using the electroplating and CVD methods. The coatings consisted of two layers: an outer, β-NiAl phase and the interdiffusion γ’-Ni3Al phase. Palladium dissolved in the whole coating, whereas hafnium and zirconium formed inclusions on the border of the layers. Samples were subjected to cyclic oxidation test at 1100 °C for 200h. Oxidation resistance of the palladium, Hf+Pd and Zr+Pd modified coatings deposited on pure nickel does not differ significantly, but is better than the oxidation resistance of the non-modified one.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Xu, Yuan-Dong, Yan-Ping Jiang, Xin-Gui Tang, Qiu-Xiang Liu, Zhenhua Tang, Wen-Hua Li, Xiao-Bin Guo e Yi-Chun Zhou. "Enhancement of Resistive Switching Performance in Hafnium Oxide (HfO2) Devices via Sol-Gel Method Stacking Tri-Layer HfO2/Al-ZnO/HfO2 Structures". Nanomaterials 13, n. 1 (22 dicembre 2022): 39. http://dx.doi.org/10.3390/nano13010039.

Testo completo

Abstract (sommario):

Resistive random-access memory (RRAM) is a promising candidate for next-generation non-volatile memory. However, due to the random formation and rupture of conductive filaments, RRMS still has disadvantages, such as small storage windows and poor stability. Therefore, the performance of RRAM can be improved by optimizing the formation and rupture of conductive filaments. In this study, a hafnium oxide-/aluminum-doped zinc oxide/hafnium oxide (HfO2/Al-ZnO/HfO2) tri-layer structure device was prepared using the sol–gel method. The oxygen-rich vacancy Al-ZnO layer was inserted into the HfO2 layers. The device had excellent RS properties, such as an excellent switch ratio of 104, retention of 104 s, and multi-level storage capability of six resistance states (one low-resistance state and five high-resistance states) and four resistance states (three low-resistance states and one high-resistance state) which were obtained by controlling stop voltage and compliance current, respectively. Mechanism analysis revealed that the device is dominated by ohmic conduction and space-charge-limited current (SCLC). We believe that the oxygen-rich vacancy concentration of the Al-ZnO insertion layer can improve the formation and rupture behaviors of conductive filaments, thereby enhancing the resistive switching (RS) performance of the device.

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Yu, J. J., Q. Fang, J. Y. Zhang, Z. M. Wang e I. W. Boyd. "Hafnium oxide layers derived by photo-assisted sol–gel processing". Applied Surface Science 208-209 (marzo 2003): 676–81. http://dx.doi.org/10.1016/s0169-4332(02)01424-1.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Lavrenko, V. A., V. N. Talash, M. Desmaison-Brut e Yu B. Rudenko. "Protective oxide layers formed during electrochemical oxidation of hafnium carbide". Powder Metallurgy and Metal Ceramics 48, n. 9-10 (settembre 2009): 595–99. http://dx.doi.org/10.1007/s11106-010-9173-0.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Siket, Christian M., Maria Bendova, Cezarina Cela Mardare, Jaromir Hubalek, Siegfried Bauer, Achim Walter Hassel e Andrei Ionut Mardare. "Interfacial Oxide Formation during Anodization of Hafnium/Aluminium Superimposed Layers". Electrochimica Acta 178 (ottobre 2015): 344–52. http://dx.doi.org/10.1016/j.electacta.2015.07.039.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Reznik, A. A., A. A. Rezvanov e S. S. Zyuzin. "Buffer Layers for Nonvolatile Ferroelectric Memory Based on Hafnium Oxide". Russian Microelectronics 52, S1 (dicembre 2023): S38—S43. http://dx.doi.org/10.1134/s1063739723600486.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Fadeev, A. V., A. V. Myakon’kikh, E. A. Smirnova, S. G. Simakin e K. V. Rudenko. "Mechanisms of the Redistribution of Carbon Contamination in Films Formed by Atomic Layer Deposition". Микроэлектроника 52, n. 4 (1 luglio 2023): 336–44. http://dx.doi.org/10.31857/s0544126923700412.

Testo completo

Abstract (sommario):

The depth distribution of carbon impurities in hafnium oxide films obtained by plasma-assisted atomic layer deposition is studied experimentally and theoretically. An analytical model is proposed that describes the dependence of the carbon impurity concentration profile in the film. The model takes into account the fact that the formation of a carbon impurity in the growing film may be caused by the incomplete oxidation of the organometallic precursor. The diffusion redistribution of impurities is determined by mech-anisms that take into account the presence of carbon in different kinds of states: an insoluble state (carbides, carbonates), a highly mobile state (CO, CO2), and an unstable state whose lifetime is longer than the film’s growth time. The possibility of controlling the carbon impurity both in deep and near-surface layers is shown. The predictions of the model are confirmed experimentally using the mass spectrometry of the secondary ions in the films obtained by atomic layer deposition. To test the theory, special structures of hafnium oxide are developed, consisting of several layers, in which the time of the plasma exposure to the sample is varied at the same dosage of the organometallic precursor. The layer with the shortest exposure time to the plasma is deposited on the substrate, then the same number of cycles on the next layer take place, provided that the exposure time is increased by a factor of n. This makes it possible to deepen the transition zones and thus pro-tect them from the effects of the atmosphere.

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Łaszcz, Adam, Andrzej Czerwiński, Jacek Ratajczak, Andrzej Taube, Sylwia Gierałtowska, Ania Piotrowska e Jerzy Kątcki. "Study of Oxides Formed in HfO₂/Si Structure for High-k Dielectric Applications". Solid State Phenomena 186 (marzo 2012): 78–81. http://dx.doi.org/10.4028/www.scientific.net/ssp.186.78.

Testo completo

Abstract (sommario):

Transmission electron microscopy (TEM) techniques were used for characterization of annealing (400, 600 and 800 °C) influence on the structural properties of the HfO2 film (45 nm thick) deposited on Si substrate. Such structures are considered as high-k dielectric materials for application in novel semiconductor devices. The studies showed that independently of the annealing temperature a very thin and flat amorphous layer is formed between HfO2 layer and Si substrate. This result was also found in the non-annealed sample. EDXS examination confirmed that the stoichiometry for the hafnium oxide layer in each sample corresponds to 1:2 for Hf:O (i.e. to HfO2). TEM images revealed differences in the microstructure of HfO2 layers in annealed samples, however the layers have similar thickness and interface roughness in all studied samples.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Ramesh, L., S. Moparthi, P. K. Tiwari, V. R. Samoju e G. K. Saramekala. "Investigation of the Electrical Properties of Double-Gate Dual-Active-Layer (DG-DAL) Thin-Film Transistor (TFT) with HfO-=SUB=-2-=/SUB=-/La-=SUB=-2-=/SUB=-O-=SUB=-3-=/SUB=-/HfO-=SUB=-2-=/SUB=- (HLH) Sandwich Gate Dielectrics". Физика и техника полупроводников 54, n. 10 (2020): 1098. http://dx.doi.org/10.21883/ftp.2020.10.49949.9395.

Testo completo

Abstract (sommario):

In this paper, the electrical properties of a double-gate dual-active-layer (DG-DAL) thin-film transistor (TFT) is investigated. To increase the ON-current and pixel intensity, and control the voltage stress bias, the conventional gate oxide material (silicon dioxide SiO2) is replaced with a tri-high-k gate dielectric layer, hafnium dioxide HfO2/lanthanum oxide La2O3/hafnium dioxide HfO2 (HLH). Further, the performance of the proposed DG-DAL structure is compared with the single-active-layer (SAL) and dual-active-layer (DAL) TFTs. The amorphous indium-gallium zinc-oxide (a-IGZO) is considered as active layer for SAL channel region, and on the other hand, a-IGZO and indium-tin-oxide (ITO) are considered as active layers for DAL TFT and DG-DAL TFT channel regions. The parameters such as OFF-current, ON-current, ION/IOFF ratio, threshold voltage, mobility, average subthreshold swing, etc. are evaluated for the considered structures. It is observed that the DG-DAL TFT with HLH dielectric offers high ON-current of 3.85·10-3 A/μm, very low OFF-current of 2.53·10-17 A/μm, very high ION/IOFF ratio of 1.51·1014, the threshold voltage of 0.642 V, high mobility of 35 cm2·v-1·s-1 and average subthreshold swing of 127.84 mV/dec. A commercial TCAD simulation tool ATLAS from SilvacoTM is used to investigate all the parameters for considered structures. Keywords: single active layer (SAL), dual active layer (DAL), double-gate dual active layer (DG-DAL), InGaZnO (IGZO), InSnO (ITO), thin-film transistor (TFT), HfO2/La2O3/HfO2 (HLH).

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Briggs, B. D., S. M. Bishop, K. D. Leedy e N. C. Cady. "Characterization of hafnium oxide resistive memory layers deposited on copper by atomic layer deposition". Thin Solid Films 562 (luglio 2014): 519–24. http://dx.doi.org/10.1016/j.tsf.2014.04.084.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Mroczyński, Robert, Magdalena Szymańska e Wojciech Głuszewski. "Reactive magnetron sputtered hafnium oxide layers for nonvolatile semiconductor memory devices". Journal of Vacuum Science & Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena 33, n. 1 (gennaio 2015): 01A113. http://dx.doi.org/10.1116/1.4906090.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Kalam, Kristjan, Markus Otsus, Jekaterina Kozlova, Aivar Tarre, Aarne Kasikov, Raul Rammula, Joosep Link et al. "Memory Effects in Nanolaminates of Hafnium and Iron Oxide Films Structured by Atomic Layer Deposition". Nanomaterials 12, n. 15 (28 luglio 2022): 2593. http://dx.doi.org/10.3390/nano12152593.

Testo completo

Abstract (sommario):

HfO2 and Fe2O3 thin films and laminated stacks were grown by atomic layer deposition at 350 °C from hafnium tetrachloride, ferrocene, and ozone. Nonlinear, saturating, and hysteretic magnetization was recorded in the films. Magnetization was expectedly dominated by increasing the content of Fe2O3. However, coercive force could also be enhanced by the choice of appropriate ratios of HfO2 and Fe2O3 in nanolaminated structures. Saturation magnetization was observed in the measurement temperature range of 5–350 K, decreasing towards higher temperatures and increasing with the films’ thicknesses and crystal growth. Coercive force tended to increase with a decrease in the thickness of crystallized layers. The films containing insulating HfO2 layers grown alternately with magnetic Fe2O3 exhibited abilities to both switch resistively and magnetize at room temperature. Resistive switching was unipolar in all the oxides mounted between Ti and TiN electrodes.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Lee, Donghyeon, Pyungho Choi, Areum Park, Woojin Jeon, Donghee Choi, Sangmin Lee e Byoungdeog Choi. "Hafnium Incorporation in InZnO Thin Film Transistors as a Carrier Suppressor". Journal of Nanoscience and Nanotechnology 20, n. 11 (1 novembre 2020): 6675–78. http://dx.doi.org/10.1166/jnn.2020.18761.

Testo completo

Abstract (sommario):

In this study, we fabricated Hf-doped indium zinc oxide thin-film transistors (HIZO TFTs) using a solution process. Channel layers of the TFTs were optimized by varying the molar ratio of Hf in the channel layers. The electrical properties of the fabricated devices were compared to gallium indium zinc oxide (GIZO). HIZO TFTs showed 0.12 V threshold voltage, 0.45 V/decade subthreshold swing and 1.24 × 106 on–off current ratio, which were excellent compared to that of GIZO. In particular, when a positive gate bias stress of 10 V was applied for 103 s, the HIZO TFT exhibited a lower threshold voltage shift of 1.11 V than the GIZO TFT (1.88 V). These results originate from the higher oxygen bonding with Hf in IZO compared to Ga atoms. We confirmed that Hf acts as an excellent carrier suppressor whose properties exceed those of Ga.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Fuchs, Christopher, Lena Fürst, Hartmut Buhmann, Johannes Kleinlein e Laurens W. Molenkamp. "Overlapping top gate electrodes based on low temperature atomic layer deposition for nanoscale ambipolar lateral junctions". Nano Futures 8, n. 2 (28 maggio 2024): 025001. http://dx.doi.org/10.1088/2399-1984/ad4c33.

Testo completo

Abstract (sommario):

Abstract We present overlapping top gate electrodes for the formation of gate defined lateral junctions in semiconducting layers as an alternative to the back gate/top gate combination and to the split gate configuration. The optical lithography microfabrication of the overlapping top gates is based on multiple layers of low-temperature atomic layer deposited hafnium oxide, which acts as a gate dielectric and as a robust insulating layer between two overlapping gate electrodes exhibiting a large dielectric breakdown field of > 1 × 10 9 V m − 1 . The advantage of overlapping gates over the split gate approach is confirmed in model calculations of the electrostatics of the gate stack. The overlapping gate process is applied to Hall bar devices of mercury telluride in order to study the interaction of different quantum Hall states in the nn′, np, pn and pp′ regime.

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Golosov, D. A., N. Vilya, S. М. Zavadski, S. N. Melnikov, A. V. Avramchuk, М. М. Grekhov, N. I. Kargin e I. V. Komissarov. "Influence of film thickness on the dielectric characteristics of hafnium oxide layers". Thin Solid Films 690 (novembre 2019): 137517. http://dx.doi.org/10.1016/j.tsf.2019.137517.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Костюк, Геннадий Игоревич, e Ирина Владимировна Кантемир. "НАУКОВІ ОСНОВИ СТВОРЕННЯ ВИСОКОЕНТРОПІЙНИХ КАРБІДНИХ ТА ОКСИДНИХ НАНОПОКРИТТІВ НА НАДТВЕРДОМУ МАТЕРІАЛІ КОРТИНИТ". Aerospace Technic and Technology, n. 3 (1 agosto 2017): 77–84. http://dx.doi.org/10.32620/aktt.2017.3.05.

Testo completo

Abstract (sommario):

The possibility of creating highly entropic carbide and oxide nanocoatings on superhard material Cortinitis based on hafnium, zircon, molybdenum, tungsten, yttrium and nickel was investigated. An investigation was made of the production of nitride, carbide, boride and oxide coatings and nitrides, carbides, borides and oxides directly in the body of the material at ion energies in the range from 200 to 2·104 eV with charge numbers from 1 to 3. Important characteristics were obtained: the grain volume for all the ions and nitrogen, carbon, boron and oxygen ions listed and their depth, which allows us to evaluate the layers of nanostructures or submicrostructures that can be formed by these high-entropy coatings. Moreover, it is shown that it is possible to avoid the production of intermetallic compounds due to the high mobility of nitrogen ions.

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Mazurak, Andrzej, Robert Mroczyński, David Beke e Adam Gali. "Silicon-Carbide (SiC) Nanocrystal Technology and Characterization and Its Applications in Memory Structures". Nanomaterials 10, n. 12 (29 novembre 2020): 2387. http://dx.doi.org/10.3390/nano10122387.

Testo completo

Abstract (sommario):

Colloidal cubic silicon-carbide nanocrystals have been fabricated, characterized, and introduced into metal–insulator–semiconductor and metal–insulator–metal structures based on hafnium oxide layers. The fabricated structures were characterized through the stress-and-sense measurements in terms of device capacitance, flat-band voltage shift, switching characteristics, and retention time. The examined electrical performance of the sample structures has demonstrated the feasibility of the application of both types of structures based on SiC nanoparticles in memory devices.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Ishizaki, Hiroki. "Growth of HfSixOy/ HfO2 Thin Film on Si Substrate by Microwave Generated Remote Plasma Assisted Atomic Layer Deposition Techniques". MRS Advances 1, n. 4 (2016): 311–16. http://dx.doi.org/10.1557/adv.2016.144.

Testo completo

Abstract (sommario):

ABSTRACTIn this paper, we will report on the formation of HfSixOy layer on an HF-last Si(100) substrate by atomic layer deposition from tetrakis(dimethylamido)hafnium (TDMAH) and atomic oxygen generated by a microwave remote plasma. Transmission electron microscopy observations of HfSixOy /Si structures deposited at 100 and 300℃ revealed that 3∼5-nm-thick amorphous HfSixOy layers were unintentionally formed preceded the growth of crystalline Hf-rich HfSixOy layers. To understand the mechanism of this unintentional growth of HfSixOy, the depth profiles of Hf, O and Si elements were measured by X-ray photoelectron spectroscopy. It was found that Hf atoms deeply diffused into the Si substrate. From these results, suppression of Hf in diffusion to the Si substrate must be important to reduce the capacitance equivalent thickness of the metal-oxide-semiconductor capacitors. The roles of TDMAH and plasma-generated oxygen radical on the enhanced diffusion of Hf will be discussed in detail.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Chae, Kisung, Andrew C. Kummel e Kyeongjae Cho. "Hafnium–zirconium oxide interface models with a semiconductor and metal for ferroelectric devices". Nanoscale Advances 3, n. 16 (2021): 4750–55. http://dx.doi.org/10.1039/d1na00230a.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Nakagawa, Hiroshi, Akio Ohta, Fumito Takeno, Satoru Nagamachi, Hideki Murakami, Seiichiro Higashi e Seiichi Miyazaki. "Characterization of Interfacial Oxide Layers in Heterostructures of Hafnium Oxides Formed on NH3-Nitrided Si(100)". Japanese Journal of Applied Physics 43, n. 11B (15 novembre 2004): 7890–94. http://dx.doi.org/10.1143/jjap.43.7890.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Guzmán-Mendoza, J., D. Albarrán-Arreguín, O. Alvarez-Fragoso, M. A. Alvarez-Perez, C. Falcony e M. García-Hipólito. "Photoluminescent characteristics of hafnium oxide layers activated with trivalent terbium (HfO2:Tb+3)". Radiation Effects and Defects in Solids 162, n. 10-11 (ottobre 2007): 723–29. http://dx.doi.org/10.1080/10420150701482519.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Mozalev, Alexander, Maria Bendova, Francesc Gispert-Guirado e Eduard Llobet. "Hafnium-Oxide 3-D Nanofilms via the Anodizing of Al/Hf Metal Layers". Chemistry of Materials 30, n. 8 (29 marzo 2018): 2694–708. http://dx.doi.org/10.1021/acs.chemmater.8b00188.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Piao, Shang Hao, Hyeonju Lee, Jaehoon Park e Hyoung Jin Choi. "Poly(4-vinylphenol-co-methyl methacrylate)/Hafnium Oxide Nanocomposite Gate Insulators for Organic Thin-Film Transistors". Journal of Nanoscience and Nanotechnology 20, n. 7 (1 luglio 2020): 4188–92. http://dx.doi.org/10.1166/jnn.2020.17567.

Testo completo

Abstract (sommario):

We fabricate 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-Pn) thin-film transistors (TFTs) with nanocomposite insulators. The insulator layers consist of both poly(4-vinylphenol-co-methyl methacrylate) and high-dielectric constant hafnium oxide (HfO2) nanoparticles. The HfO2 nanoparticles are ball-milled for sufficient dispersion in a nanocomposite solution to enable solution process methods to be used in preparing the insulator layers. The nanocomposite insulators demonstrate high capacitances and improve the performance of TIPS-Pn TFTs. Nonetheless, particle aggregates are produced in the nanocomposites solution with high HfO2 concentrations, generating detrimental effects on the dielectric properties and the TFT performance. Our experimental result implies that the optimum concentration of HfO2 nanoparticles in a mixed solution will find to be ~11.5 wt%.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Wang, Chi-Chieh, Cheng-Fu Wang, Meng-Chi Li, Li-Chen Su e Chien-Cheng Kuo. "Inhibition of Anti-Reflection Film Cracks on Plastic Substrates Using Nanolaminate Layer Deposition in Plasma-Enhanced Atomic Layer Deposition". Technologies 13, n. 1 (28 dicembre 2024): 11. https://doi.org/10.3390/technologies13010011.

Testo completo

Abstract (sommario):

In this research, we mainly increase the adhesion of PMMA substrate and film, which is reflected in the environmental test. This study used plasma-enhanced atomic layer deposition (PEALD) to find the relationship between the intensity of XRD reflection peak and the root-mean-square surface roughness (σRMS) of hafnium dioxide (HfO2) at different thicknesses by reducing the plasma power at different process temperatures. In this experiment, HfO2 was found to have the highest intensity of XRD at its maximum thickness. According to the different intensities of XRD of HfO2 at different thicknesses, aluminum oxide (Al2O3) was inserted as crystallization cutoff layers, and the two materials were combined into nanolaminates. The corresponding σRMS value also changed from 1.25 to 0.434 nm after treatment under the fourth experimental design. This study improved this mismatch between interfaces by adjusting the yield strength and ductility using Al2O3 layers and by creating an inhibition layer. In addition, through the processing of inserted Al2O3 layers, the degree of crystallization was changed so that the material and substrate could maintain their normal surfaces without cracking after the environmental tests. After inserting five 1 nm thick Al2O3 layers, the environmental test results were improved. The test time was increased from the original 56 h to 352 h.

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Ibrahim, Omar A. "Organic Field Effect Transistor Based on P3HT with Two Different Gate Dielectrics". BASRA JOURNAL OF SCIENCE 39, n. 2 (1 aprile 2021): 234–42. http://dx.doi.org/10.29072/basjs.202125.

Testo completo

Abstract (sommario):

The electrical performance of bottom-gate/top source-drain contact for p-channel organic field-effect transistors (OFETs) using poly(3-hexylthiophene) (P3HT) as an active semiconductor layer with two different gate dielectric materials, Polyvinylpyrrolidone (PVP) and Hafnium oxide (HfO2), is investigated in this work. The output and transfer characteristics were studied for HfO2, PVP and HfO2/PVP as organic gate insulator layer. Both characteristics show a high drain current at the gate dielectric HfO2/PVP equal to -0.0031A and -0.0015A for output and transfer characteristics respectively, this can be attributed to the increasing of the dielectric capacitance. Transcondactance characteristics also studied for the three organic materials and show the HfO2/PVP gate dielectric have higher value from the single layers which indicate the effect of dielectric capacitance, gm=-0.5517x10-4A/V, -0.9931x10-5A/V, and -0.6511 x10-4A/V respectively.

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Han, Dong-Suk, Jae-Hyung Park, Min-Soo Kang, Duck-Kyun Choi e Jong-Wan Park. "Highly stable hafnium–tin–zinc oxide thin film transistors with stacked bilayer active layers". Current Applied Physics 15, n. 2 (febbraio 2015): 94–97. http://dx.doi.org/10.1016/j.cap.2014.11.007.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Shah, Deb Kumar, Devendra KC, Ahmad Umar, Hassan Algadi, Mohammad Shaheer Akhtar e O.-Bong Yang. "Influence of Efficient Thickness of Antireflection Coating Layer of HfO2 for Crystalline Silicon Solar Cell". Inorganics 10, n. 10 (12 ottobre 2022): 171. http://dx.doi.org/10.3390/inorganics10100171.

Testo completo

Abstract (sommario):

Anti-reflective coating (ARC) layers on silicon (Si) solar cells usually play a vital role in the amount of light absorbed into the cell and protect the device from environmental degradation. This paper reports on the thickness optimization of hafnium oxide (HfO2) as an ARC layer for high-performance Si solar cells with PC1D simulation analysis. The deposition of the HfO2 ARC layer on Si cells was carried out with a low-cost sol-gel process followed by spin coating. The thickness of the ARC layer was controlled by varying the spinning speed. The HfO2 ARC with a thickness of 70 nm possessed the lowest average reflectance of 6.33% by covering wavelengths ranging from 400–1000 nm. The different thicknesses of HfO2 ARC layers were used as input parameters in a simulation study to explore the photovoltaic characteristics of Si solar cells. The simulation findings showed that, at 70 nm thickness, Si solar cells had an exceptional external quantum efficiency (EQE) of 98% and a maximum power conversion efficiency (PCE) of 21.15%. The thicknesses of HfO2 ARC considerably impacted the photovoltaic (PV) characteristics of Si solar cells, leading to achieving high-performance solar cells.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Pereira, Luís, Pedro Barquinha, Elvira Fortunato e Rodrigo Martins. "Electrical Performances of Low Temperature Annealed Hafnium Oxide Deposited at Room Temperature". Materials Science Forum 514-516 (maggio 2006): 58–62. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.58.

Testo completo

Abstract (sommario):

In this work, HfO2 was deposited by r.f. sputtering at room temperature and then annealed for different times at 200°C in a forming gas atmosphere. After annealing for 2 hours the HfO2 layers present a reduction on the flat band voltage of about 1 V, relatively to the as deposited film, decreasing from -2.23V down to -1.28 V. This means an improvement of the interface properties and a reduction on the oxide charge density from 1.33×1012 cm-2 to 7.62×1011 cm-2. The dielectric constant reaches a maximum of 18.3 after 5h annealing due to film’s densification. When annealing for longer times such as 10h a small degradation of the electrical properties is observed. After 10h annealing the dielectric constant, flat band voltage and fixed charge density are respectively, 14.9, -2.96 V and 1.64 ×1012 cm-2 and the leakage current also increases due to film’s crystallization.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Lo Nigro, Raffaella, Patrick Fiorenza, Giuseppe Greco, Emanuela Schilirò e Fabrizio Roccaforte. "Structural and Insulating Behaviour of High-Permittivity Binary Oxide Thin Films for Silicon Carbide and Gallium Nitride Electronic Devices". Materials 15, n. 3 (22 gennaio 2022): 830. http://dx.doi.org/10.3390/ma15030830.

Testo completo

Abstract (sommario):

High-κ dielectrics are insulating materials with higher permittivity than silicon dioxide. These materials have already found application in microelectronics, mainly as gate insulators or passivating layers for silicon (Si) technology. However, since the last decade, the post-Si era began with the pervasive introduction of wide band gap (WBG) semiconductors, such as silicon carbide (SiC) and gallium nitride (GaN), which opened new perspectives for high-κ materials in these emerging technologies. In this context, aluminium and hafnium oxides (i.e., Al2O3, HfO2) and some rare earth oxides (e.g., CeO2, Gd2O3, Sc2O3) are promising high-κ binary oxides that can find application as gate dielectric layers in the next generation of high-power and high-frequency transistors based on SiC and GaN. This review paper gives a general overview of high-permittivity binary oxides thin films for post-Si electronic devices. In particular, focus is placed on high-κ binary oxides grown by atomic layer deposition on WBG semiconductors (silicon carbide and gallium nitride), as either amorphous or crystalline films. The impacts of deposition modes and pre- or postdeposition treatments are both discussed. Moreover, the dielectric behaviour of these films is also presented, and some examples of high-κ binary oxides applied to SiC and GaN transistors are reported. The potential advantages and the current limitations of these technologies are highlighted.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Glowka, Karsten, Maciej Zubko, Paweł Świec, Krystian Prusik, Magdalena Szklarska, Dariusz Chrobak, János L. Lábár e Danuta Stróż. "Influence of Molybdenum on the Microstructure, Mechanical Properties and Corrosion Resistance of Ti20Ta20Nb20(ZrHf)20−xMox (Where: x = 0, 5, 10, 15, 20) High Entropy Alloys". Materials 15, n. 1 (5 gennaio 2022): 393. http://dx.doi.org/10.3390/ma15010393.

Testo completo

Abstract (sommario):

The presented work was focused on investigating the influence of the (hafnium and zirconium)/molybdenum ratio on the microstructure and properties of Ti20Ta20Nb20(ZrHf)20−xMox (where: x = 0, 5, 10, 15, 20 at.%) high entropy alloys in an as-cast state. The designed chemical composition was chosen due to possible future biomedical applications. Materials were obtained from elemental powders by vacuum arc melting technique. Phase analysis revealed the presence of dual body-centered cubic phases. X-ray diffraction showed the decrease of lattice parameters of both phases with increasing molybdenum concentration up to 10% of molybdenum and further increase of lattice parameters. The presence of two-phase matrix microstructure and hafnium and zirconium precipitates was proved by scanning and transmission electron microscopy observation. Mechanical property measurements revealed decreased micro- and nanohardness and reduced Young’s modulus up to 10% of Mo content, and further increased up to 20% of molybdenum addition. Additionally, corrosion resistance measurements in Ringers’ solution confirmed the high biomedical ability of studied alloys due to the presence of stable oxide layers.

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Berger, Steffen, Florian Jakubka e Patrik Schmuki. "Self-Ordered Hexagonal Nanoporous Hafnium Oxide and Transition to Aligned HfO[sub 2] Nanotube Layers". Electrochemical and Solid-State Letters 12, n. 7 (2009): K45. http://dx.doi.org/10.1149/1.3117253.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

42

García-Hipólito, M., U. Caldiño, O. Alvarez-Fragoso, M. A. Alvarez-Pérez, R. Martínez-Martínez e C. Falcony. "Violet-blue luminescence from hafnium oxide layers doped with CeCl3prepared by the spray pyrolysis process". physica status solidi (a) 204, n. 7 (luglio 2007): 2355–61. http://dx.doi.org/10.1002/pssa.200622341.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Sialini, P., P. Sajdl, V. Havránek e V. Vrtílková. "Study of diffusion processes in the oxide layer of zirconium alloys". Koroze a ochrana materialu 60, n. 1 (1 marzo 2016): 1–5. http://dx.doi.org/10.1515/kom-2016-0004.

Testo completo

Abstract (sommario):

Abstract In the active zone of a nuclear reactor where zirconium alloys are used as a coating material, this material is subject to various harmful impacts. During water decomposition reactions, hydrogen and oxygen are evolved that may diffuse through the oxidic layer either through zirconium dioxide (ZrO2) crystals or along ZrO2 grains. The diffusion mechanism can be studied using the Ion Beam Analysis (IBA) method where nuclear reaction 18O(p,α)15N is used. A tube made of zirconium alloy E110 (with 1 wt. % of Nb) was used for making samples that were pre-exposed in UJP PRAHA a.s. and subsequently exposed to isotopically cleansed environment of H2 18O medium in an autoclave. The samples were analysed with gravimetric methods and IBA methods performed at the electrostatic particle accelerator Tandetron 4130 MC in the Nucler Physics Institute of the CAS, Řež. With IBA methods, the overall thicknesses of corrosion layers on the samples, element composition of the alloy and distribution of oxygen isotope 18O in the corrosion layer and its penetration in the alloy were identified. The retrieved data shows at the oxygen diffusion along ZrO2 grains because there are two peaks of 18O isotope concentrations in the corrosion layer. These peaks occur at the environment-oxide and oxide-metal interface. The element analysis identified the presence of undesirable hafnium.

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Yan Ny Tan, W. K. Chim, Wee Kiong Choi, Moon Sig Joo e Byung Jin Cho. "Hafnium aluminum oxide as charge storage and blocking-oxide layers in SONOS-type nonvolatile memory for high-speed operation". IEEE Transactions on Electron Devices 53, n. 4 (aprile 2006): 654–62. http://dx.doi.org/10.1109/ted.2006.870273.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Shakhno, Elena A., Quang D. Nguyen, Dmitry A. Sinev, Elizaveta V. Matvienko, Roman A. Zakoldaev e Vadim P. Veiko. "Laser Thermochemical High-Contrast Recording on Thin Metal Films". Nanomaterials 11, n. 1 (30 dicembre 2020): 67. http://dx.doi.org/10.3390/nano11010067.

Testo completo

Abstract (sommario):

Laser-induced thermochemical recording of nano- and microsized structures on thin films has attracted intense interest over the last few decades due to essential applications in the photonics industry. Nevertheless, the relationship between the laser parameters and the properties of the formed oxide structures, both geometrical and optical, is still implicit. In this work, direct laser interference patterning of the titanium (Ti) film in the oxidative regime was applied to form submicron periodical structures. Depending on the number of laser pulses, the regime of high contrast structures recording was observed with the maximum achievable thickness of the oxide layer. The investigation revealed high transmittance of the formed oxide layers, i.e., the contrast of recorded structures reached up to 90% in the visible range. To analyze the experimental results obtained, a theoretical model was developed based on calculations of the oxide formation dynamics. The model operates on Wagner oxidation law and the corresponding optical properties of the oxide–metal–glass substrate system changing nonlinearly after each pulse. A good agreement of the experimental results with the modeling estimations allowed us to extend the model application to other metals, specifically to those with optically transparent oxides, such as zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), and tantalum (Ta). The performed analysis highlighted the importance of choosing the correct laser parameters due to the complexity and nonlinearity of optical, thermal, and chemical processes in the metal film during its laser-induced oxidation in the air. The developed model allowed selecting the suitable temporal–energetic regimes and predicting the optical characteristics of the structures formed with an accuracy of 10%. The results are promising in terms of their implementation in the photonics industry for the production of optical converters.

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Zulkifli, Zikri, Norshamsuri Ali, Shaili Falina, Hiroshi Kawarada, Mohamed Fauzi Packeer Mohamed e Mohd Syamsul. "Comparison of the Electrical Performance of AlN and HfO<sub>2 </sub>Passivation Layer in AlGaN/GaN HEMT". Key Engineering Materials 947 (31 maggio 2023): 21–26. http://dx.doi.org/10.4028/p-445y05.

Testo completo

Abstract (sommario):

Different material thickness with medium and high dielectric constant can impact the performance and reliability of high electron mobility transistor device. With varying the thickness of the passivation layer, the effect of it towards the device performance is still unclear. Two different insulator layers with a medium dielectric and a high dielectric constant namely Aluminium Nitride and Hafnium Oxide are used as passivation layer in AlGaN/GaN HEMT. Both material performance was simulated via COMSOL software by varying the thickness and the drain current output were compared. The passivation layer thickness of 10nm at Vds=6 V and Vgs=5 V, HfO2 outperforms AlN with the output drain current of 39 mA compared to 35 mA respectively. It was observed that HfO2 can attain higher threshold voltage, Vth as compared to the AlN because of the influence of its material properties that shows a direct proportional relationship between Vth and dielectric constant. Using high dielectric constant material like HfO2, we observe the ON-voltage gradually decreases as the thickness of the passivation layer increased. Out of all the thickness simulated for HfO2 and AlN, 10nm produced the highest drain current output instead of layer thickness of 20nm.

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Sugawara, Takuya, Yasuhiro Oshima, Raghavasimhan Sreenivasan e Paul C. McIntyre. "Electrical properties of germanium/metal-oxide gate stacks with atomic layer deposition grown hafnium-dioxide and plasma-synthesized interface layers". Applied Physics Letters 90, n. 11 (12 marzo 2007): 112912. http://dx.doi.org/10.1063/1.2472197.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Martínez-Martínez, R., M. García, A. Speghini, M. Bettinelli, C. Falcony e U. Caldiño. "Blue–green–red luminescence from CeCl3- and MnCl2-doped hafnium oxide layers prepared by ultrasonic spray pyrolysis". Journal of Physics: Condensed Matter 20, n. 39 (1 settembre 2008): 395205. http://dx.doi.org/10.1088/0953-8984/20/39/395205.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Ting, Guy G., Orb Acton, Hong Ma, Jae Won Ka e Alex K. Y. Jen. "Study on the Formation of Self-Assembled Monolayers on Sol−Gel Processed Hafnium Oxide as Dielectric Layers". Langmuir 25, n. 4 (17 febbraio 2009): 2140–47. http://dx.doi.org/10.1021/la802944n.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Hussin, H., N. Soin, M. F. Bukhori, S. Wan Muhamad Hatta e Y. Abdul Wahab. "Effects of Gate Stack Structural and Process Defectivity on High-kDielectric Dependence of NBTI Reliability in 32 nm Technology Node PMOSFETs". Scientific World Journal 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/490829.

Testo completo

Abstract (sommario):

We present a simulation study on negative bias temperature instability (NBTI) induced hole trapping inE′center defects, which leads to depassivation of interface trap precursor in different geometrical structures of high-kPMOSFET gate stacks using the two-stage NBTI model. The resulting degradation is characterized based on the time evolution of the interface and hole trap densities, as well as the resulting threshold voltage shift. By varying the physical thicknesses of the interface silicon dioxide (SiO2) and hafnium oxide (HfO2) layers, we investigate how the variation in thickness affects hole trapping/detrapping at different stress temperatures. The results suggest that the degradations are highly dependent on the physical gate stack parameters for a given stress voltage and temperature. The degradation is more pronounced by 5% when the thicknesses of HfO2are increased but is reduced by 11% when the SiO2interface layer thickness is increased during lower stress voltage. However, at higher stress voltage, greater degradation is observed for a thicker SiO2interface layer. In addition, the existence of different stress temperatures at which the degradation behavior differs implies that the hole trapping/detrapping event is thermally activated.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "Hafnium oxide layers"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili