A wideband cryogenic microwave low-noise amplifier

• Boris I. Ivanov,
• Dmitri I. Volkhin,
• Ilya L. Novikov,
• Dmitri K. Pitsun,
• Dmitri O. Moskalev,
• Ilya A. Rodionov,
• Evgeni Il’ichev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1484–1491, doi:10.3762/bjnano.11.131

• of liquid helium [11][12][13][14][15][16] and are, usually, placed at the 4 K stage of dilution refrigerators. These amplifiers can be implemented using two modern semiconductor transistor technologies, that is, high-electron-mobility transistor (HEMT) technology, including GaAs and InP, and SiGe

• heterojunction bipolar technology (HBT). Recently, it has been shown that cryogenic amplifiers based on SiGe HBT [16][17][18] can provide low noise levels and high gain at 4 K. They are suitable for superconducting qubit readout [25][26] and radio astronomy systems [12][14]. In order to obtain high gain values

Cryogenic low-noise amplifiers for measurements with superconducting detectors

• Ilya L. Novikov,
• Boris I. Ivanov,
• Dmitri V. Ponomarev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1316–1320, doi:10.3762/bjnano.11.115

• mobility transistor (HEMT) technology and SiGe bipolar heterojunction technology (HBT). Low-frequency amplifiers are usually applied as first stage of SQUID readout electronics [11][12] or as the readout of cryogenic bolometers [13]. In both cases the amplifiers have a working temperature of 300 K. Modern

Fabrication and characterization of Si_1−xGe_x nanocrystals in as-grown and annealed structures: a comparative study

• Muhammad Taha Sultan,
• Adrian Valentin Maraloiu,
• Ionel Stavarache,
• Jón Tómas Gudmundsson,
• Andrei Manolescu,
• Valentin Serban Teodorescu,
• Magdalena Lidia Ciurea and
• Halldór Gudfinnur Svavarsson

Beilstein J. Nanotechnol. 2019, 10, 1873–1882, doi:10.3762/bjnano.10.182

• , 050094 Bucharest, Romania 10.3762/bjnano.10.182 Abstract Multilayer structures comprising of SiO2/SiGe/SiO2 and containing SiGe nanoparticles were obtained by depositing SiO2 layers using reactive direct current magnetron sputtering (dcMS), whereas, Si and Ge were co-sputtered using dcMS and high-power

• measurements, to explore structural changes and corresponding properties. It is observed that the employment of HiPIMS facilitates the formation of SiGe nanoparticles (2.1 ± 0.8 nm) in the as-grown structure, and that presence of such nanoparticles acts as a seed for heterogeneous nucleation, which upon

• annealing results in the periodically arranged columnar self-assembly of SiGe core–shell nanocrystals. An increase in photocurrent intensity by more than an order of magnitude was achieved by annealing. Furthermore, a detailed discussion is provided on strain development within the structures, the

Sputtering of silicon nanopowders by an argon cluster ion beam

• Xiaomei Zeng,
• Vasiliy Pelenovich,
• Zhenguo Wang,
• Wenbin Zuo,
• Sergey Belykh,
• Alexander Tolstogouzov,
• Dejun Fu and
• Xiangheng Xiao

Beilstein J. Nanotechnol. 2019, 10, 135–143, doi:10.3762/bjnano.10.13

• compared to the sputtering of the bulk target. The sputtering yield versus radius of a-Si or SiGe particles scaled to the energy deposition depth has been studied by Nietiadi et al. using MD and Monte Carlo simulations [20][21]. As projectiles, Ar atoms were used with an energy of 20 keV. The sputtering

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

• Grenoble, France 10.3762/bjnano.9.184 Abstract In this paper, we present an enhanced differential Hall effect measurement method (DHE) for ultrathin Si and SiGe layers for the investigation of dopant activation in the surface region with sub-nanometre resolution. In the case of SiGe, which constitutes the

• thick SiGe test structure fabricated by CVD and uniformly doped in situ during growth. The developed method is finally applied to the investigation of dopant activation achieved by advanced annealing methods (including millisecond and nanosecond laser annealing) in two material systems: 6 nm thick

• increase of the active dopant concentration at the surface of the source/drain material (usually Si or SiGe) is a key factor for obtaining a resistance reduction [6], and several process solutions have been proposed to this purpose, involving advanced implanting or annealing techniques [7]. Within this

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

• -effect transistor (JL TFET); nanoscale; SiGe; Introduction In the last years, the continuous miniaturization of nanoscale transistors induces new challenges including short-channel effects (SCEs) and high power consumption, which prevent incorporating conventional metal-oxide semiconductor field-effect

• 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

• applications. Moreover, this study can be extended by investigating the impact of other parameters such as the interfacial defects between both Si and SiGe materials and the degradation-related ageing effects including stress. To do so, new complex models and numerical simulations need to be developed

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

• Liga Jasulaneca,
• Jelena Kosmaca,
• Raimonds Meija,
• Jana Andzane and
• Donats Erts

Beilstein J. Nanotechnol. 2018, 9, 271–300, doi:10.3762/bjnano.9.29

Nanostructuring of GeTiO amorphous films by pulsed laser irradiation

• Valentin S. Teodorescu,
• Cornel Ghica,
• Adrian V. Maraloiu,
• Mihai Vlaicu,
• Andrei Kuncser,
• Magdalena L. Ciurea,
• Ionel Stavarache,
• Ana M. Lepadatu,
• Nicu D. Scarisoreanu,
• Andreea Andrei,
• Valentin Ion and
• Maria Dinescu

Beilstein J. Nanotechnol. 2015, 6, 893–900, doi:10.3762/bjnano.6.92

• induce photonic effects, such as the diffusivity enhancement of atomic species due to the lattice bonds softening [20][21][22] in the strong field of the laser pulse. High values of atomic diffusivity were observed for Ge diffusion in the case of laser crystallization annealing of SiGe amorphous film [18

• diffusivities are much smaller than in the liquid phase as the fraction of the broken bonds in the viscous phase is much smaller than in the liquid phase. The fast diffusion of Ge in the solid matrix was also evidenced in the case of laser irradiation of amorphous SiGe films [18]. The prolonged high-resolution

Bright photoluminescence from ordered arrays of SiGe nanowires grown on Si(111)

• D. J. Lockwood,
• N. L. Rowell,
• A. Benkouider,
• A. Ronda,
• L. Favre and
• I. Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2498–2504, doi:10.3762/bjnano.5.259

• Marseille Cedex 20, France 10.3762/bjnano.5.259 Abstract We report on the optical properties of SiGe nanowires (NWs) grown by molecular beam epitaxy (MBE) in ordered arrays on SiO2/Si(111) substrates. The production method employs Au catalysts with self-limited sizes deposited in SiO2-free sites opened-up

• ordered SiGe NW arrays with predefined NW positions and diameters. Here we report on the optical properties of such MBE grown NWs. Experimental A schematic overview of the various steps used in the growth process is given in Figure 1. The steps consisted of: (a) rapid thermal oxidation (RTO); (b) FIB

• patterning; (c) galvanic selective deposition of Au; (d) induced phase transition in AuSi catalysts; and (e) selective growth of SiGe NWs. With this method we have produced Si1−xGex NWs with diameters in the range 50–200 nm, although the size can potentially be tuned between 30 and 300 nm, and with Ge

Review of nanostructured devices for thermoelectric applications

• Giovanni Pennelli

Beilstein J. Nanotechnol. 2014, 5, 1268–1284, doi:10.3762/bjnano.5.141

• temperature range, because silicon is a very stable material for temperatures in excess of 900 K. Silicon–germanium alloys, SiGe [38][39], and superlattices [40][41] showed a good Z factor value, of the order of 2 × 10−3 K−1 at 800 K. Furthermore, they can be used for power generation in devices exploiting

Photoresponse from single upright-standing ZnO nanorods explored by photoconductive AFM

• Igor Beinik,
• Markus Kratzer,
• Astrid Wachauer,
• Lin Wang,
• Yuri P. Piryatinski,
• Gerhard Brauer,
• Xin Yi Chen,
• Yuk Fan Hsu,
• Aleksandra B. Djurišić and
• Christian Teichert

Beilstein J. Nanotechnol. 2013, 4, 208–217, doi:10.3762/bjnano.4.21

• through the substrate [32][33][34][38], we use here a configuration of PC-AFM where the sample is illuminated from the top as already successfully applied to Si and SiGe nanostructures [39][40]. Such a scheme allows us to stay away from any limitations imposed by the substrate. Here, we employ this

Review and outlook: from single nanoparticles to self-assembled monolayers and granular GMR sensors

• Alexander Weddemann,
• Inga Ennen,
• Anna Regtmeier,
• Camelia Albon,
• Annalena Wolff,
• Katrin Eckstädt,
• Nadine Mill,
• Michael K.-H. Peter,
• Jochen Mattay,
• Carolin Plattner,
• Norbert Sewald and
• Andreas Hütten

Beilstein J. Nanotechnol. 2010, 1, 75–93, doi:10.3762/bjnano.1.10

• similar structures with a mismatch of below 10%. SiGe [32] and AuAg [33] are systems of this type. Undefined structure with a concentration gradient. The requirements are similar to the second class but the component distribution is controlled kinetically. CoFe is a well known example [30] (see Figure 6