Graphene-enhanced metal oxide gas sensors at room temperature: a review

• Dongjin Sun,
• Yifan Luo,
• Marc Debliquy and
• Chao Zhang

Beilstein J. Nanotechnol. 2018, 9, 2832–2844, doi:10.3762/bjnano.9.264

• ], graphene has been widely used in various fields such as photocatalysts, lithium battery electrodes, supercapacitors, gas sensors and electronic devices [2][3][4] due to its high specific surface area (2630 m2/g) and high carrier mobility at room temperature [5]. The electrical properties of graphene are

Contactless photomagnetoelectric investigations of 2D semiconductors

• Marian Nowak,
• Marcin Jesionek,
• Barbara Solecka,
• Piotr Szperlich,
• Piotr Duka and
• Anna Starczewska

Beilstein J. Nanotechnol. 2018, 9, 2741–2749, doi:10.3762/bjnano.9.256

• carrier mobility on the concentration of electrons and holes induced by a back-gate voltage. Conclusion: The presented contactless PME method, used in Corbino geometry, is complementary to the mobility extraction methods based on field-effect measurements. It can be used for determining the mobility and

• diffusion length of carriers in different 2D materials. Keywords: carrier mobility; contactless investigations; graphene; photomagnetoelectric effect; 2D materials; Introduction The application of two-dimensional (2D) materials in electronic devices [1][2][3][4][5][6] requires the development of

• appropriate measurement methods for determining their typical semiconductor parameters, i.e., carrier mobility (μ) and lifetime (τ). Among these methods, contactless techniques [7][8] and mobility extraction methods based on field-effect measurements [9] are of great importance. Here we show a contactless

Optimization of Mo/Cr bilayer back contacts for thin-film solar cells

• Nima Khoshsirat,
• Fawad Ali,
• Vincent Tiing Tiong,
• Mojtaba Amjadipour,
• Hongxia Wang,
• Mahnaz Shafiei and
• Nunzio Motta

Beilstein J. Nanotechnol. 2018, 9, 2700–2707, doi:10.3762/bjnano.9.252

• more dense grains as compared with the films deposited at higher pressure and lower power. This results in less grain boundaries and consequently higher carrier mobility and conductivity. The SEM images also show more uniform surfaces over the film area for the samples deposited at 3 mTorr compared

High-temperature magnetism and microstructure of a semiconducting ferromagnetic (GaSb)_1−x(MnSb)_x alloy

• Leonid N. Oveshnikov,
• Elena I. Nekhaeva,
• Alexey V. Kochura,
• Alexander B. Davydov,
• Mikhail A. Shakhov,
• Sergey F. Marenkin,
• Oleg A. Novodvorskii,
• Alexander P. Kuzmenko,
• Alexander L. Vasiliev,
• Boris A. Aronzon and
• Erkki Lahderanta

Beilstein J. Nanotechnol. 2018, 9, 2457–2465, doi:10.3762/bjnano.9.230

• granular systems are the higher values of carrier mobility, about one order of magnitude higher than that in traditional DMS such as Ga1−xMnxAs. This is due to the aggregation of the majority of magnetic impurity atoms within nanoinclusions, which results in a higher crystalline quality of the

• which MFM image (f) was made. Sample parameters: deposition temperature Tdep; film thickness d; carrier concentration Np; carrier mobility μ; coercive force Hc; remanent magnetization Mrem; saturation magnetization Msat (Np, μ and Msat were obtained at T = 300 K, while the values of Hc and Mrem

Intrinsic ultrasmall nanoscale silicon turns n-/p-type with SiO₂/Si₃N₄-coating

• Dirk König,
• Daniel Hiller,
• Noël Wilck,
• Birger Berghoff,
• Merlin Müller,
• Sangeeta Thakur,
• Giovanni Di Santo,
• Luca Petaccia,
• Joachim Mayer,
• Sean Smith and
• Joachim Knoch

Beilstein J. Nanotechnol. 2018, 9, 2255–2264, doi:10.3762/bjnano.9.210

• [13][14]. This concept eliminates doping altogether, leading to a lower inelastic carrier scattering rate and higher carrier mobility which allow for decreased heat loss and bias voltages in ULSI. Such properties enable Si-FET technology to work at even smaller structure sizes, potentially enabling

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• -charged cations, such as Sn2+, Mn2+, or Ge2+, where the tin-based materials have gained the most attention and progress [10][16][18][29][30][38][44][54][59][60][61][62][63][64][65]. The Sn-based HPs (CsSnX3, MASnX3) show a high charge carrier mobility and diffusion length, comparable to the Pb-based

• luminescent Cs3Bi2X9 NCs [159]. A study of single-crystal and polycrystalline MABI showed that both materials have a long exciton lifetime and a high carrier mobility [161][163]. A transient absorption study of MABI crystals showed only a minor change of the exciton dynamics when the crystal size was reduced

A variable probe pitch micro-Hall effect method

• Maria-Louise Witthøft,
• Frederik W. Østerberg,
• Janusz Bogdanowicz,
• Rong Lin,
• Henrik H. Henrichsen,
• Ole Hansen and
• Dirch H. Petersen

Beilstein J. Nanotechnol. 2018, 9, 2032–2039, doi:10.3762/bjnano.9.192

• characterization of ultrathin films with minimal sample preparation. Here, we study in detail how the analysis of raw measurement data affects the accuracy of extracted key sample parameters, i.e., how the standard deviation on sheet resistance, carrier mobility and Hall sheet carrier density is affected by the

• ; in that case, the better method depends on the experimental conditions, i.e., the distance between the insulating boundary and the electrodes. Improvement to the accuracy of Hall Effect measurement results is crucial for nanoscale metrology, since surface scattering often leads to low carrier

• mobility. Keywords: four-point probes; Hall effect; metrology; mobility; variable Probe Pitch; Introduction Materials characterization becomes increasingly difficult as the dimensions of transistors continue to decrease. Although three dimensional electrical characterization is the ultimate goal of

A differential Hall effect measurement method with sub-nanometre resolution for active dopant concentration profiling in ultrathin doped Si_1−xGe_x and Si layers

• Richard Daubriac,
• Emmanuel Scheid,
• Hiba Rizk,
• Richard Monflier,
• Sylvain Joblot,
• Rémi Beneyton,
• Pablo Acosta Alba,
• Sébastien Kerdilès and
• Filadelfo Cristiano

Beilstein J. Nanotechnol. 2018, 9, 1926–1939, doi:10.3762/bjnano.9.184

• SiGeOI and 11 nm thick SOI. In both cases, DHE is shown to be a uniquely sensitive characterisation technique for a detailed investigation of dopant activation in ultrashallow layers, providing sub-nanometre resolution for both dopant concentration and carrier mobility depth profiles. Keywords: carrier

• measured without any assumption about the magnitude of the carrier mobility. In addition, measurements are made by stripping the material in successive steps rather than bevelling the surface. The depth resolution of the final dopant concentration profile is therefore defined by the etch rate and indeed

• discontinuity throughout the two measurement runs. On the other hand, the sheet resistance RS constantly increases (while the Hall dose NH decreases) and exhibits a discontinuity between the two runs. Indeed, as the doping concentration is uniform throughout the doped layer, the associated carrier mobility is

The role of the Ge mole fraction in improving the performance of a nanoscale junctionless tunneling FET: concept and scaling capability

• Hichem Ferhati,
• Fayçal Djeffal and
• Toufik Bentrcia

Beilstein J. Nanotechnol. 2018, 9, 1856–1862, doi:10.3762/bjnano.9.177

• temperatures in the current equations [25]. Moreover, models for carrier recombination (Shockley–Read–Hall (SRH), Auger and surface recombination) are also adopted [26]. In fact, the carrier mobility mainly depends on three quantities, transverse and parallel electric field, doping and temperature, which were

• combined using Matthiessen’s formula. Accordingly, the Lombardi model (CVT) is used to express the carrier mobility in the channel [27]. Moreover, the intrinsic parameters of the materials (Si, Si1−xGex and Ge) such as band gap, mobility and the density of states were considered to be dependent on the Ge

• mainly due to the enhanced carrier mobility caused by the increased Ge content. Moreover, introducing SiGe at the source side can be effective for reducing the tunneling barrier. Besides, the Ge concentration increase induces a lowering of the tunneling barrier, which enables enhancing the derived

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• conductivity. Tuning the band structure of the catalyst is important for improving the HER efficiency. It was reported that the band structure and carrier mobility of monolayer MX2 can be tuned by substitution of M with M' atoms or X with X' atoms to form monolayer MxM'(1−x)X2 or MX2xX'2(1−x) alloys [31][32

Multimodal noncontact atomic force microscopy and Kelvin probe force microscopy investigations of organolead tribromide perovskite single crystals

• Yann Almadori,
• David Moerman,
• Jaume Llacer Martinez,
• Philippe Leclère and
• Benjamin Grévin

Beilstein J. Nanotechnol. 2018, 9, 1695–1704, doi:10.3762/bjnano.9.161

• , including a direct band gap, high absorption coefficient, large and balanced carrier mobility, high diffusion length, long carrier lifetime and high photoluminescence quantum yield. Within a few years of their discovery, these materials were successfully used to develop photovoltaic cells [2] with power

Predicting the strain-mediated topological phase transition in 3D cubic ThTaN₃

• Chunmei Zhang and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1399–1404, doi:10.3762/bjnano.9.132

• to note that the conduction band (CB) of ThTaN3 is very dispersive around the Γ point, signifying a very low electron effective mass. The effective mass of the electron at the Γ point is calculated to be 0.395 me. Such a small electron mass will greatly improve charge carrier mobility, suggesting

The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• with permission from [134], copyright 2014 Royal Society of Chemistry. Formation of gold nanoparticles in a bithiazole–benzothiazole-based polymer matrix and their role as a template for the self-assembly of the bulk polymer leading to enhancement of the charge-carrier mobility. Reprinted with

Substrate and Mg doping effects in GaAs nanowires

• Perumal Kannappan,
• Nabiha Ben Sedrine,
• Jennifer P. Teixeira,
• Maria R. Soares,
• Bruno P. Falcão,
• Maria R. Correia,
• Nestor Cifuentes,
• Emilson R. Viana,
• Marcus V. B. Moreira,
• Geraldo M. Ribeiro,
• Alfredo G. de Oliveira,
• Juan C. González and
• Joaquim P. Leitão

Beilstein J. Nanotechnol. 2017, 8, 2126–2138, doi:10.3762/bjnano.8.212

• for application in solar cells owing to their high absorption, direct bandgap, high carrier mobility and well-developed synthesis techniques [5][6][7][8][9]. Among the group III–V semiconductors, GaAs is one of the most intensively studied materials and has a suitable bandgap energy value for solar

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• . Keywords: dielectric; encapsulation layer; flexible substrate; organic field effect transistor; Parylene C; Review Introduction An improvement of the performance of organic transistors by means of boosting charge-carrier mobility is one of the main quests in organic electronics, calling for novel design

• [17]. Measured variations of the charge-carrier mobility [18] were assigned either to mechanical changes in the semiconductor film or to charge trapping at the dielectric/semiconductor and semiconductor/electrode interfaces. It should be pointed out that the primary element affecting the transistor

• properties do not change after mechanical tests. The remaining transistor parameters such as charge carrier mobility, subthreshold and threshold voltage also remain practically unaffected by mechanical testing. The threshold voltage value, 0.44 V for the unbent device, became slightly reduced down to 0.42 V

Light-induced magnetoresistance in solution-processed planar hybrid devices measured under ambient conditions

• Sreetama Banerjee,
• Daniel Bülz,
• Danny Reuter,
• Karla Hiller,
• Dietrich R. T. Zahn and
• Georgeta Salvan

Beilstein J. Nanotechnol. 2017, 8, 1502–1507, doi:10.3762/bjnano.8.150

• observed at room temperature even in ambient atmosphere. TIPS-pentacene is an ideal candidate for this proof of concept, as it is a solution-processable molecule that exhibits high carrier mobility and air-stability [10][11]. Moreover, the existence of light-induced magnetoresistance in TIPS-pentacene was

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• -called spin blocking can be cancelled by the magnetic field. The spin mixing seems to be most pronounced in the slow hopping regime [84], for instance, when deep traps reduce the charge carrier mobility [85]. Oppositely charged polaron pairs [16] (or correlated radical ion pairs) can show a bipolar OMAR

Two-dimensional silicon and carbon monochalcogenides with the structure of phosphorene

• Dario Rocca,
• Ali Abboud,
• Ganapathy Vaitheeswaran and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2017, 8, 1338–1344, doi:10.3762/bjnano.8.135

• [10][11], one of the many phases of crystalline phosphorus. Among other properties [12][13][14][15], the values of the carrier mobility and of the on–off ratio of transistors made from phosphorene are intermediate between the values of graphene and those of transition metal dichalcogenides, making

• phosphorene very promising for certain applications. Additionaly, phosphorene is characterized by a strong anisotropy in the carrier mobility [14] and ferroelasticity [16]. Recently, some parent compounds to phosphorene have been considered. For example, P–As compounds were studied theoretically and

The integration of graphene into microelectronic devices

• Guenther Ruhl,
• Sebastian Wittmann,
• Matthias Koenig and
• Daniel Neumaier

Beilstein J. Nanotechnol. 2017, 8, 1056–1064, doi:10.3762/bjnano.8.107

• technology. The fascinating properties of graphene, such as extremely high charge carrier mobility of more than 200,000 cm2·V−1·s−1 [3], was consistently shown in academic research. For instance, a sheet of high-quality graphene sandwiched between two exfoliated single-crystalline hexagonal boron nitride (h

• -BN) sheets shows a charge carrier mobility of 200,000 cm2·V−1·s−1 [4], which is about 300 times higher than that of silicon. However, if graphene is integrated in real-world devices with the constraints of manufacturability, the properties of graphene and its devices dramatically degrade. The

• charge carrier mobility. Several studies have been conducted on this topic [35][36], but the impact on manufacturability is still not very clear. However, there is continuous improvement towards large crystallite sizes in the millimeter range [37][38]. 2.2 Contamination Another important intrinsic

CVD transfer-free graphene for sensing applications

• Chiara Schiattarella,
• Sten Vollebregt,
• Tiziana Polichetti,
• Brigida Alfano,
• Ettore Massera,
• Maria Lucia Miglietta,
• Girolamo Di Francia and
• Pasqualina Maria Sarro

Beilstein J. Nanotechnol. 2017, 8, 1015–1022, doi:10.3762/bjnano.8.102

• literature for CVD graphene (between 102 and 103 cm2/V·s), in the calculations, a carrier mobility of μ ≈ 1000 cm2/V·s has been assumed [29][30][31]. During the exposure, the number of carriers per unit surface has changed by the fraction ΔG/G0 in 10 min. This quantity is linked to the number of adsorbed

First examples of organosilica-based ionogels: synthesis and electrochemical behavior

• Andreas Taubert,
• Ruben Löbbicke,
• Barbara Kirchner and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2017, 8, 736–751, doi:10.3762/bjnano.8.77

• activation of energy Ea of 0.6 eV between −20 °C and 20 °C and subsequently with an Ea of 0.45 eV from 20 °C to 80 °C. It shows that the charge-carrier mobility is less activated with temperature when the temperature increases. The conductivities obtained from the measurements are comparable to other IGs

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• packed, atomically thin layer of sp2 hybridised carbon atoms arranged in a honeycomb network. Since the first report in 2004 [1], graphene has attracted great interest in the scientific community due to its unique properties such as superior charge carrier mobility, high transparency, excellent

• extremely high carrier mobility, high carrier density, and low intrinsic noise for better detection by virtue of the high signal-to-noise ratio. In the anchored structure, electroactive NPs are anchored on the GS (Figure 1c) [76], and in the mixed structure, the graphene and NPs are synthesised separately

Graphene functionalised by laser-ablated V₂O₅ for a highly sensitive NH₃ sensor

• Margus Kodu,
• Artjom Berholts,
• Tauno Kahro,
• Mati Kook,
• Peeter Ritslaid,
• Helina Seemen,
• Tea Avarmaa,
• Harry Alles and
• Raivo Jaaniso

Beilstein J. Nanotechnol. 2017, 8, 571–578, doi:10.3762/bjnano.8.61

• concentration of defects to the graphene 2D crystal lattice. These defects decrease the charge carrier mobility in graphene which is reflected in reduced electrical conductivity. As compared to the pristine sensor, the response to both gases is clearly improved after the functionalisation by PLD. The response

Role of oxygen in wetting of copper nanoparticles on silicon surfaces at elevated temperature

• Tapas Ghosh and
• Biswarup Satpati

Beilstein J. Nanotechnol. 2017, 8, 425–433, doi:10.3762/bjnano.8.45

• nanostructure fabrication have been carried out. CuO is a p-type semiconductor with a band gap of 1.4 eV [1][2]. Higher conductivity has been observed in CuO as compared to Cu2O, although higher carrier mobility has been observed in Cu2O [3]. However, the higher stability of CuO makes it more applicable. In the