Showing papers on "Silicon published in 2003"
TL;DR: In this article, the influence of source-drain contact thermal annealing and surface passivation on key transistor properties was examined, and it was shown that thermal annaling and passivation of oxide defects using chemical modification can increase the average transconductance from 45 to 800 nS and average mobility from 30 to 560 cm 2 /V
Abstract: Silicon nanowires can be prepared with single-crystal structures, diameters as small as several nanometers and controllable hole and electron doping, and thus represent powerful building blocks for nanoelectronics devices such as field effect transistors. To explore the potential limits of silicon nanowire transistors, we have examined the influence of source-drain contact thermal annealing and surface passivation on key transistor properties. Thermal annealing and passivation of oxide defects using chemical modification were found to increase the average transconductance from 45 to 800 nS and average mobility from 30 to 560 cm 2 /V‚s with peak values of 2000 nS and 1350 cm 2 /V‚s, respectively. The comparison of these results and other key parameters with state-of-the-art planar silicon devices shows substantial advantages for silicon nanowires. The uses of nanowires as building blocks for future nanoelectronics are discussed.
2,157 citations
TL;DR: The thermal conductivities of individual single crystalline intrinsic Si nanowires with diameters of 22, 37, 56, and 115 nm were measured using a microfabricated suspended device over a temperature range of 20-320 K as discussed by the authors.
Abstract: The thermal conductivities of individual single crystalline intrinsic Si nanowires with diameters of 22, 37, 56, and 115 nm were measured using a microfabricated suspended device over a temperature range of 20–320 K. Although the nanowires had well-defined crystalline order, the thermal conductivity observed was more than two orders of magnitude lower than the bulk value. The strong diameter dependence of thermal conductivity in nanowires was ascribed to the increased phonon-boundary scattering and possible phonon spectrum modification.
1,596 citations
TL;DR: A new technique for fabricating silicon oxide nanopores with single-nanometre precision and direct visual feedback, using state-of-the-art silicon technology and transmission electron microscopy is reported.
Abstract: Single nanometre-sized pores (nanopores) embedded in an insulating membrane are an exciting new class of nanosensors for rapid electrical detection and characterization of biomolecules. Notable examples include α-hemolysin protein nanopores in lipid membranes1,2 and solid-state nanopores3 in Si3N4. Here we report a new technique for fabricating silicon oxide nanopores with single-nanometre precision and direct visual feedback, using state-of-the-art silicon technology and transmission electron microscopy. First, a pore of 20 nm is opened in a silicon membrane by using electron-beam lithography and anisotropic etching. After thermal oxidation, the pore can be reduced to a single-nanometre when it is exposed to a high-energy electron beam. This fluidizes the silicon oxide leading to a shrinking of the small hole due to surface tension. When the electron beam is switched off, the material quenches and retains its shape. This technique dramatically increases the level of control in the fabrication of a wide range of nanodevices.
1,375 citations
TL;DR: In this paper, the etch rates of 53 materials that are used or potentially can be used or in the fabrication of microelectromechanical systems and integrated circuits were prepared.
Abstract: Samples of 53 materials that are used or potentially can be used or in the fabrication of microelectromechanical systems and integrated circuits were prepared: single-crystal silicon with two doping levels, polycrystalline silicon with two doping levels, polycrystalline germanium, polycrystalline SiGe, graphite, fused quartz, Pyrex 7740, nine other preparations of silicon dioxide, four preparations of silicon nitride, sapphire, two preparations of aluminum oxide, aluminum, Al/2%Si, titanium, vanadium, niobium, two preparations of tantalum, two preparations of chromium, Cr on Au, molybdenum, tungsten, nickel, palladium, platinum, copper, silver, gold, 10 Ti/90 W, 80 Ni/20 Cr, TiN, four types of photoresist, resist pen, Parylene-C, and spin-on polyimide. Selected samples were etched in 35 different etches: isotropic silicon etchant, potassium hydroxide, 10:1 HF, 5:1 BHF, Pad Etch 4, hot phosphoric acid, Aluminum Etchant Type A, titanium wet etchant, CR-7 chromium etchant, CR-14 chromium etchant, molybdenum etchant, warm hydrogen peroxide, Copper Etchant Type CE-200, Copper Etchant APS 100, dilute aqua regia, AU-5 gold etchant, Nichrome Etchant TFN, hot sulfuric+phosphoric acids, Piranha, Microstrip 2001, acetone, methanol, isopropanol, xenon difluoride, HF+H/sub 2/O vapor, oxygen plasma, two deep reactive ion etch recipes with two different types of wafer clamping, SF/sub 6/ plasma, SF/sub 6/+O/sub 2/ plasma, CF/sub 4/ plasma, CF/sub 4/+O/sub 2/ plasma, and argon ion milling. The etch rates of 620 combinations of these were measured. The etch rates of thermal oxide in different dilutions of HF and BHF are also reported. Sample preparation and information about the etches is given.
1,256 citations
TL;DR: An ‘epitaxial casting’ approach for the synthesis of single-crystal GaN nanotubes with inner diameters of 30–200 nm and wall thicknesses of 5–50nm is reported, applicable to many other semiconductor systems.
Abstract: Since the discovery of carbon nanotubes in 1991 (ref. 1), there have been significant research efforts to synthesize nanometre-scale tubular forms of various solids. The formation of tubular nanostructure generally requires a layered or anisotropic crystal structure. There are reports of nanotubes made from silica, alumina, silicon and metals that do not have a layered crystal structure; they are synthesized by using carbon nanotubes and porous membranes as templates, or by thin-film rolling. These nanotubes, however, are either amorphous, polycrystalline or exist only in ultrahigh vacuum. The growth of single-crystal semiconductor hollow nanotubes would be advantageous in potential nanoscale electronics, optoelectronics and biochemical-sensing applications. Here we report an 'epitaxial casting' approach for the synthesis of single-crystal GaN nanotubes with inner diameters of 30-200 nm and wall thicknesses of 5-50 nm. Hexagonal ZnO nanowires were used as templates for the epitaxial overgrowth of thin GaN layers in a chemical vapour deposition system. The ZnO nanowire templates were subsequently removed by thermal reduction and evaporation, resulting in ordered arrays of GaN nanotubes on the substrates. This templating process should be applicable to many other semiconductor systems.
1,169 citations
TL;DR: These hydrogen-terminated SiNW surfaces seem to be more oxidation-resistant than regular silicon wafer surfaces, because atomically resolved STM images of SiNWs were obtained in air after several days' exposure to the ambient environment.
Abstract: Small-diameter (1 to 7 nanometers) silicon nanowires (SiNWs) were prepared, and their surfaces were removed of oxide and terminated with hydrogen by a hydrofluoric acid dip. Scanning tunneling microscopy (STM) of these SiNWs, performed both in air and in ultrahigh vacuum, revealed atomically resolved images that can be interpreted as hydrogen-terminated Si (111)-(1 × 1) and Si (001)-(1 × 1) surfaces corresponding to SiH 3 on Si (111) and SiH 2 on Si (001), respectively. These hydrogen-terminated SiNW surfaces seem to be more oxidation-resistant than regular silicon wafer surfaces, because atomically resolved STM images of SiNWs were obtained in air after several days9 exposure to the ambient environment. Scanning tunneling spectroscopy measurements were performed on the oxide-removed SiNWs and were used to evaluate the electronic energy gaps. The energy gaps were found to increase with decreasing SiNW diameter from 1.1 electron volts for 7 nanometers to 3.5 electron volts for 1.3 nanometers, in agreement with previous theoretical predictions.
1,095 citations
TL;DR: In this article, the authors present the history, the present status and possible future developments of photovoltaic (PV) materials for terrestrial applications and discuss the physical and technical limitations of this material.
Abstract: This paper reviews the history, the present status and possible future developments of photovoltaic (PV) materials for terrestrial applications. After a brief history and introduction of the photovoltaic effect theoretical requirements for the optimal performance of materials for pn-junction solar cells are discussed. Most important are efficiency, long-term stability and, not to be neglected, lowest possible cost. Today the market is dominated by crystalline silicon in its multicrystalline and monocrystalline form. The physical and technical limitations of this material are discussed. Although crystalline silicon is not the optimal material from a solid state physics point of view it dominates the market and will continue to do this for the next 5–10 years. Because of its importance a considerable part of this review deals with materials aspects of crystalline silicon. For reasons of cost only multicrystalline silicon and monocrystalline Czochralski (Cz) crystals are used in practical cells. Light induced instability in this Cz-material has recently been investigated and ways to eliminate this effect have been devised. For future large scale production of crystalline silicon solar cells development of a special solar grade silicon appears necessary. Ribbon growth is a possibility to avoid the costly sawing process. A very vivid R&D area is thin-film crystalline silicon (about 5–30 μm active layer thickness) which would avoid the crystal growing and sawing processes. The problems arising for this material are: assuring adequate light absorption, assuring good crystal quality and purity of the films, and finding a substrate that fulfills all requirements. Three approaches have emerged: high-temperature, low-temperature and transfer technique. Genuine thin-film materials are characterized by a direct band structure which gives them very high light absorption. Therefore, these materials have a thickness of only one micron or less. The oldest such material is amorphous silicon which is the second most important material today. It is mainly used in consumer products but is on the verge to also penetrate the power market. Other strong contenders are chalcogenides like copper indium diselenide (CIS) and cadmium telluride. The interest has expanded from CuInSe 2 , to CuGaSe 2 , CuInS 2 and their multinary alloys Cu(In,Ga)(S,Se) 2 . The two deposition techniques are either separate deposition of the components followed by annealing on one hand or coevaporation. Laboratory efficiencies for small area devices are approaching 19% and large area modules have reached 12%. Pilot production of CIS-modules has started in the US and Germany. Cadmium telluride solar cells also offer great promise. They have only slightly lower efficiency and are also at the start of production. In the future other materials and concepts can be expected to come into play. Some of these are: dye sensitized cells, organic solar cells and various concentrating systems including III/V-tandem cells. Theoretical materials that have not yet been realized are Auger generation material and intermediate metallic band material.
919 citations
TL;DR: In this paper, the ReaxFFSiO, reactive force field was developed to predict the structures, properties, and chemistry of materials involving silicon and silicon oxides; interfaces between these materials; and hydrolysis of such systems, and the parameters for this force field were obtained from fitting to the results of quantum chemical (QC) calculations on the structures and energy barriers for a number of silicon oxide clusters.
Abstract: To predict the structures, properties, and chemistry of materials involving silicon and silicon oxides; interfaces between these materials; and hydrolysis of such systems, we have developed the ReaxFFSiO, reactive force field. The parameters for this force field were obtained from fitting to the results of quantum chemical (QC) calculations on the structures and energy barriers for a number of silicon oxide clusters and on the equations of state for condensed phases of Si and SiO2 from QC. We expect that ReaxFFSiO will allow accurate dynamical simulations of bond breaking processes in large silicon and silicon oxide systems. ReaxFFSiO is based closely on the potential functions of the ReaxFFCH reactive force field for hydrocarbons, so that it should also be useful for describing reactions of organics with Si and SiO2 systems.
799 citations
TL;DR: In this article, anode materials of nanostructured silicon have been prepared by physical vapor deposition and characterized using electrochemical methods, and electrodes were prepared in thin-film form as nanocrystalline particles (12 nm mean diameter) and as continuous amorphous thin films (100 nm thick).
Abstract: Anode materials of nanostructured silicon have been prepared by physical vapor deposition and characterized using electrochemical methods. The electrodes were prepared in thin-film form as nanocrystalline particles (12 nm mean diameter) and as continuous amorphous thin films (100 nm thick). The nanocrystalline silicon exhibited specific capacities of around 1100 mAh/g with a 50% capacity retention after 50 cycles. The amorphous thin-film electrodes exhibited initial capacities of 3500 mAh/g with a stable capacity of 2000 mAh/g over 50 cycles. We suggest that the nanoscale dimensions of the silicon circumvents conventional mechanisms of mechanical deterioration, permitting good cycle life.
691 citations
TL;DR: These analyses identified the MEMS component materials, gold, silicon nitride, silicon dioxide, SU-8(TM), and silicon as biocompatible, with gold and silicon showing reduced biofouling.
596 citations
TL;DR: In this paper, the oxide-assisted growth (OAG) technique was proposed for the growth of nanostructured materials. But the OAG technique is not suitable for high-purity silicon nanowires.
Abstract: In this contribution, we outline oxide-assisted growth (OAG) (distinct from the conventional metal-catalytic vapor-liquid-solid (VLS) process) for the growth of nanostructured materials. This synthesis technique, in whichoxides instead of metals play an important role in inducing the nucleation and growth of nanowires, is capable of producing large quantities of high-purity silicon nanowires with a preferential growth direction, uniform size, and long length, without the need for a metal catalyst. The OAG 1D nanomaterials synthesis is complementary to, and coexistent with, the conventional metal-catalyst VLS approach, and can be utilized to produce nanowires from a host of materials other than Si including Ge nanowires, carbon nanowires, silicon and SnO 2 nanoribbons, and Group III-V and II-VI compound semiconductor nanowires.
TL;DR: A bottom-up approach to integrate multiwalled carbon nanotubes (MWNTs) into multilevel interconnects in silicon integrated-circuit manufacturing is reported in this paper.
Abstract: We report a bottom-up approach to integrate multiwalled carbon nanotubes (MWNTs) into multilevel interconnects in silicon integrated-circuit manufacturing. MWNTs are grown vertically from patterned catalyst spots using plasma-enhanced chemical vapor deposition. We demonstrate the capability to grow aligned structures ranging from a single tube to forest-like arrays at desired locations. SiO2 is deposited to encapsulate each nanotube and the substrate, followed by a mechanical polishing process for planarization. MWNTs retain their integrity and demonstrate electrical properties consistent with their original structure.
TL;DR: Detailed and unambiguous simulation evidence is provided that the transition in supercooled liquid silicon, in the Stillinger–Weber potential18, is thermodynamically of first order and indeed occurs between two liquid states, as originally predicted by Aptekar10.
Abstract: Silicon in its liquid and amorphous forms occupies a unique position among amorphous materials. Obviously important in its own right, the amorphous form is structurally close to the group of 4–4, 3–5 and 2–6 amorphous semiconductors that have been found to have interesting pressure-induced semiconductor-to-metal phase transitions1,2. On the other hand, its liquid form has much in common, thermodynamically, with water and other ‘tetrahedral network’ liquids that show density maxima3,4,5,6,7. Proper study of the ‘liquid–amorphous transition’, documented for non-crystalline silicon by both experimental and computer simulation studies8,9,10,11,12,13,14,15,16,17, may therefore also shed light on phase behaviour in these related materials. Here, we provide detailed and unambiguous simulation evidence that the transition in supercooled liquid silicon, in the Stillinger–Weber potential18, is thermodynamically of first order and indeed occurs between two liquid states, as originally predicted by Aptekar10. In addition we present evidence to support the relevance of spinodal divergences near such a transition, and the prediction3 that the transition marks a change in the liquid dynamic character from that of a fragile liquid to that of a strong liquid.
TL;DR: It is demonstrated that porphyrin-based molecules bound to Si(100), which exhibit redox behavior useful for information storage, can meet this challenge of competing with semiconductors under the extreme conditions required for processing and operating a practical device.
Abstract: If molecular components are to be used as functional elements in place of the semiconductor-based devices present in conventional microcircuitry, they must compete with semiconductors under the extreme conditions required for processing and operating a practical device. Herein, we demonstrate that porphyrin-based molecules bound to Si(100), which exhibit redox behavior useful for information storage, can meet this challenge. These molecular media in an inert atmosphere are stable under extremes of temperature (400°C) for extended periods (approaching 1 hour) and do not degrade under large numbers of read-write cycles (10 12 ).
IBM1
TL;DR: In this paper, a six-band k⋅p model has been used to study the mobility of holes in Si inversion layers for different crystal orientations, for both compressive or tensile strain applied to the channel, and for a varying thickness of the Si layer.
Abstract: A six-band k⋅p model has been used to study the mobility of holes in Si inversion layers for different crystal orientations, for both compressive or tensile strain applied to the channel, and for a varying thickness of the Si layer. Scattering assisted by phonons and surface roughness has been accounted for, also comparing a full anisotropic model to an approximated isotropic treatment of the matrix elements. Satisfactory qualitative (and in several cases also quantitative) agreement is found between experimental data and theoretical results for the density and temperature dependence of the mobility for (001) surfaces, as well as for the dependence of the mobility on surface orientation [for the (011) and (111) surfaces]. Both compressive and tensile strain are found to enhance the mobility, while confinement effects result in a reduced hole mobility for a Si thickness ranging from 30 to 3 nm.
TL;DR: In this paper, the authors show that the mechanism of electrochemical alloying is electrochemically-driven solid state amorphization, a process closely analogous to the diffusive solid-state amomorphization of thin films.
TL;DR: In this article, a photonic model for quasiperiodic multilayer structures, which are built experimentally by alternating porous silicon layers with high and low refractive indices, is presented.
Abstract: Porous silicon is an efficient photo- and electro-luminescent material and represents a promising candidate for opto-electronic applications On the other hand, quasiperiodic structures have been shown to be effective media for light localization and third harmonic generation In this work, we present a photonic model for quasiperiodic multilayer structures, which are built experimentally by alternating porous silicon layers with high and low refractive indices The analysis of the light propagation through these structures is based on the transfer matrix theory The theoretical reflectance spectrum is compared with experimental data, observing a good agreement
TL;DR: The properties of amorphous 250 nm and 1 μm silicon films deposited by radiofrequency (RF) magnetron sputtering on copper foil are investigated using X-ray diffraction, scanning electron microscopy (SEM), and electrochemical methods as mentioned in this paper.
Abstract: The properties of amorphous 250 nm and 1 μm silicon films deposited by radio-frequency (rf) magnetron sputtering on copper foil are investigated using X-ray diffractιon, scanning electron microscopy (SEM), and electrochemical methods. Galvanostatic half-cell electrochemical measurements conducted between 0.02 and 1.2 V using a lithium counter electrode have shown that the 250 nm Si thin films exhibit an excellent reversible specific capacity of nearly 3500 mAh/g when tested for 30 cycles. The high reversible capacity and excellent cyclability of the 250 nm sputtered silicon thin films suggest excellent adhesion between Si and Cu leading to high capacity retention. SEM analysis conducted on the 250 nm Si films after the 30th charge suggests the good adhesion of the ∼2 μm diam "plates" of silicon to the copper substrate.
TL;DR: In this paper, the authors describe the introduction of hydrogenated microcrystalline silicon (μc-Si:H) as novel absorber material for thin-film silicon solar cells.
TL;DR: In this article, the first observation of Stimulated Raman Scattering (SRS) in silicon waveguides was reported, using a 1427 nm pump laser with a CW power of 1.6 W, measured before the waveguide.
Abstract: We report the first observation of Stimulated Raman Scattering (SRS) in silicon waveguides. Amplification of the Stokes signal, at 1542.3 nm, of up to 0.25 dB has been observed in Silicon-on-Insulator (SOI) waveguides, using a 1427 nm pump laser with a CW power of 1.6 W, measured before the waveguide. Two-Photon-Absorption (TPA) measurements on these waveguides are also reported, and found to be negligible at the pump power where SRS was observed.
TL;DR: In this paper, a variety of organic and biopolymers are constructed from one-dimensional photonic crystals, which can be dissolved or melted, by templating the solution-cast or injection-molded materials in porous silicon or porous silicon dioxide multilayer structures.
Abstract: Elaborate one-dimensional photonic crystals are constructed from a variety of organic and biopolymers, which can be dissolved or melted, by templating the solution-cast or injection-molded materials in porous silicon or porous silicon dioxide multilayer (rugate dielectric mirror) structures. After the removal of the template by chemical dissolution, the polymer castings replicate the photonic features and the nanostructure of the master. We demonstrate that these castings can be used as vapor sensors, as deformable and tunable optical filters, and as self-reporting, bioresorbable materials.
TL;DR: AlGaN-GaN power high-electron mobility transistors (HEMTs) with 600-V breakdown voltage are fabricated and demonstrated as switching power devices for motor drive and power supply applications.
Abstract: AlGaN-GaN power high-electron mobility transistors (HEMTs) with 600-V breakdown voltage are fabricated and demonstrated as switching power devices for motor drive and power supply applications. The fabricated power HEMT realized the high breakdown voltage by optimized field plate technique and the low on-state resistance of 3.3 m/spl Omega/cm/sup 2/, which is 20 times lower than that or silicon MOSFETs, thanks to the high critical field of GaN material and the high mobility in 2DEG channel. The fabricated devices also demonstrated the high current density switching of 850 A/cm/sup 2/ turn-off. These results show that AlGaN-GaN power-HEMTs are one of the most promising candidates for future switching power device for power electronics applications.
TL;DR: In this paper, a carbon-coated silicon powder was studied as a means of preparation of silicon-based anode material for lithium ion batteries, and it was shown that there is irreversible reduction of crystallinity of the silicon content.
Patent•
23 Jul 2003
TL;DR: In this article, a process for manufacturing an improved PMOS semiconductor transistor is described, where the source and drain films are made of an alloy of silicon and germanium.
Abstract: A process is described for manufacturing an improved PMOS semiconductor transistor. Recesses are etched into a layer of epitaxial silicon. Source and drain films are deposited in the recesses. The source and drain films are made of an alloy of silicon and germanium. The alloy is epitaxially deposited on the layer of silicon. The alloy thus has a lattice having the same structure as the structure of the lattice of the layer of silicon. However, due to the inclusion of the germanium, the lattice of the alloy has a larger spacing than the spacing of the lattice of the layer of silicon. The larger spacing creates a stress in a channel of the transistor between the source and drain films. The stress increases IDSAT and IDLIN of the transistor. An NMOS transistor can be manufactured in a similar manner by including carbon instead of germanium, thereby creating a tensile stress.
TL;DR: The efficiencies of solar cells using two-component particles are comparable to those of devices prepared from solution at comparable illumination conditions, and that they are not affected by the choice of solvent used in the miniemulsion process.
Abstract: Polymer layers can exhibit significantly improved performances if they possess a multicomponent phase-separated morphology. We present two approaches to control the dimensions of phase separation in thin polymer-blend layers; both rely on polymer nanospheres prepared by the miniemulsion process. In the first approach, heterophase solid layers are prepared from an aqueous dispersion containing nanoparticles of two polymers, whereas in the second approach, both polymers are already contained in each individual nanoparticle. In both cases, the upper limit for the dimension of phase separation is determined by the size of the individual nanoparticles, which can be adjusted down to a few tens of nanometres. We also show that the efficiencies of solar cells using two-component particles are comparable to those of devices prepared from solution at comparable illumination conditions, and that they are not affected by the choice of solvent used in the miniemulsion process.
TL;DR: In this article, a tensile strain induced band gap shrinkage is shown for Ge-on-Si pin diodes, which is attributed to the difference of thermal expansion between Ge and Si.
Abstract: Band gap shrinkage induced by tensile strain is shown for Ge directly grown on Si substrate. In Ge-on-Si pin diodes, photons having energy lower than the direct band gap of bulk Ge were efficiently detected. According to photoreflectance measurement, this property is due to band gap shrinkage. The origin of the shrinkage is not the Franz–Keldysh effect but rather tensile strain. It is discussed that the generation of such a tensile strain can be ascribed to the difference of thermal expansion between Ge and Si. Advantages of this tensile Ge for application to photodiode are also discussed.
TL;DR: In this article, a technique was developed for high-yield fabrication of single-crystalline-silicon cantilevers as thin as 12 nm, and the formed cantilever resonators were characterized by resonance testing in high vacuum.
Abstract: Ultrathin resonant cantilevers are promising for ultrasensitive detection. A technique is developed for high-yield fabrication of single-crystalline-silicon cantilevers as thin as 12 nm. The formed cantilever resonators are characterized by resonance testing in high vacuum. Significant specimen size effect on Young’s modulus of ultrathin (12–170 nm) silicon is detected. The Young’s modulus decreases monotonously as the cantilevers become thinner. The size effect is consistent with the published simulation results of direct-atomistic model, in which surface effects are taken into consideration.
TL;DR: In this paper, the transverse relaxation (decoherence) times of donor electron spins in phosphorus-doped silicon (Si:P) were shown to be over 2 orders of magnitude longer than previously demonstrated.
Abstract: Donor electron spins in phosphorus-doped silicon (Si:P) are a candidate two-level system (qubit) for quantum information processing. Spin echo measurements of isotopically purified ${}^{28}\mathrm{S}\mathrm{i}:\mathrm{P}$ are presented that show exceptionally long transverse relaxation (decoherence) times, ${T}_{2},$ at low temperature. Below $\ensuremath{\sim}10\mathrm{K}$ the spin decoherence is shown to be controlled by instantaneous diffusion and at higher temperatures by an Orbach process. ${T}_{2}$ for small pulse turning angles is 14 ms at 7 K and extrapolates to $\ensuremath{\sim}60\mathrm{ms}$ for an isolated spin, over 2 orders of magnitude longer than previously demonstrated.
TL;DR: In this paper, the growth of single-crystalline silicon nanowires was carried out through an electroless metal deposition process in a conventional autoclave containing aqueous HF and AgNO3 solution near room temperature.
Abstract: This article concerns the detailed investigations on the silver dendrite-assisted growth of single-crystalline silicon nanowires, and their possible self-assembling nanoelectrochemistry growth mechanism. The growth of silicon nanowires was carried out through an electroless metal deposition process in a conventional autoclave containing aqueous HF and AgNO3 solution near room temperature. In order to explore the mechanism and prove the centrality of silver dendrites in the growth of silicon nanowires, other etching solution systems with different metal species were also investigated in this work. The morphology of etched silicon substrates strongly depends upon the composition of the etching solution, especially the metal species. Our experimental results prove that the simultaneous formation of silver dendrites is a guarantee of the preservation of free-standing nanoscale electrolytic cells on the silicon substrate, and also assists in the final formation of silicon nanowire arrays on the substrate surface.