We utilize a very sensitive electron spin resonance technique called spin-dependent tunneling to identify defect centers involved in the negative bias temperature instability in plasma-nitrided p-channel metal-oxide-silicon field-effect transistors. The defect's ²⁹Si hyperfine... (Read more)

Through a combined application of two characterization methods, deep-level transient spectroscopy and lifetime spectroscopy, the lifetime-limiting defect level in intentionally aluminum-contaminated Czochralski silicon has been analyzed and a complete set of defect parameters could be obtained. This... (Read more)

The authors combine metal oxide semiconductor (MOS) gated diode measurements and very sensitive electrically detected electron spin resonance measurements to detect and identify negative bias temperature instability (NBTI) generated defect centers in fully processed HfO₂ pMOS field effect... (Read more)

The impact of a submonolayer of HfO₂ sandwiched between the SiON gate dielectric and the polycrystalline silicon layer on the low frequency noise of a n-channel metal oxide semiconductor field effect transistor is investigated. Fermi-level pinning at polycrystalline... (Read more)

Fluorine-vacancy (FV) complexes have been directly observed in the Si_0.94Ge_0.06 layer in a Si-SiGe-Si structure, using variable-energy positron annihilation spectroscopy (VEPAS). These complexes are linked to the significant reduction of boron diffusion in the SiGe layer via... (Read more)

In this paper we present a systematic study on the formation of He ion implantation induced nanovoids in Si and how they influence the self-interstitial (Is) supersaturation, thus affecting the diffusion and electrical activation of implanted boron in crystalline silicon. We implanted He ions... (Read more)

Electron spin resonance measurements on 4 and 40 nm thick (HfO₂)_0.6(SiO₂)_0.4 and (HfO₂)_0.4(SiO₂)_0.6 high-κ films on (100)Si wafers detected P_b0 and P_b1... (Read more)

Recent work has suggested that prior determinations of diffusion mechanism and point defect thermodynamics in silicon have been affected by nonequilibrium effects stemming from uncontrolled adsorption-induced suppression of a pathway for defect creation at the surface. Through silicon self-diffusion... (Read more)

We have studied, using ab initio density functional theory calculations, substitutional and interstitial Hf impurities in c-Si, for various charge states. Our results indicate that (1) the tetrahedral interstitial defect is energetically more favorable than the substitutional and (2)... (Read more)

A computationally efficient hybrid Green's function (GF) technique is developed for multiscale modeling of point defects in a trilayer lattice system that links seamlessly the length scales from lattice (subnanometers) to continuum (bulk). The model accounts for the discrete structure of the lattice... (Read more)

The local order around Mn atoms in the Mn-implanted Si samples, with ferromagnetic properties, has been investigated by use of x-ray-absorption spectroscopy techniques. Analysis of both extended x-ray-absorption fine structure and x-ray absorption near-edge structure spectra clearly indicates that... (Read more)

The rearrangement of silicon dangling bonds induced by pulsed laser heating of monohydride-covered Si(001) surfaces has been studied by means of scanning tunneling microscopy (STM). The initial configurations, which were created by laser-induced thermal desorption, consist of isolated pairs of... (Read more)

The effect of HF etching of the silicon oxide shell covering the surface of Si nanocrystals (NCs) on the subsequent room-temperature atmospheric oxidation of Si-NCs has been investigated by means of photoluminescence measurements, Fourier transform infrared spectroscopy, and electron paramagnetic... (Read more)

Structural and magnetic properties in Mn-implanted, p-type Si were investigated. High resolution structural analysis techniques such as synchrotron x-ray diffraction revealed the formation of MnSi_1.7 nanoparticles already in the as-implanted samples. Depending on the Mn fluence,... (Read more)

We investigate, through ab initio density-functional theory calculations, the electronic and structural properties of neutral Mn impurities at tetrahedral interstitial and substitutional sites in both Si and Ge layers of a Si/Ge heterostructure. We conclude that substitutional Mn at the Ge... (Read more)

The optical properties of vertically stacked self-assembled GaN/AlN quantum dots (QD's) grown on Si substrates were studied by means of temporally and spatially resolved cathodoluminescence (CL). An analysis of the CL spectra, thermal activation energies, and measured decay times of the QD... (Read more)

The annealing of damage generated by low-energy ion implantation in polycrystalline silicon (poly-Si) and amorphous silicon (a-Si) is compared. The rate of heat release between implantation temperature and 350–500 °C for Si implanted in both materials and for different ions implanted in... (Read more)

The vibrational lifetimes of a range of H-related defects and interstitial O (O_i) in Si, including isotopic substitutions, are calculated from first principles as a function of temperature. The theoretical approach is explained in detail. The vibrational lifetimes of... (Read more)

We present a detailed study of the comparative thermal evolutions of H- and D-related defects in silicon implanted with 2×10¹⁶ H or D/cm², or coimplanted with 0.25×10¹⁶ He/cm² and 0.7×10¹⁶ H/cm², in both orders.... (Read more)

We have measured positron lifetime and Doppler broadening in highly As-doped silicon containing thermally generated V-As₃ defect complexes (vacancy is surrounded by three arsenic atoms). We observe positron detrapping from the V-As₃ defect complex and determine... (Read more)

We report the diffusion of boron, arsenic, and phosphorus in silicon isotope multilayer structures at temperatures between 850 °C and 1100 °C. The diffusion of all dopants and self-atoms at a given temperature is modeled with the same setting of all native-point-defect-related parameters.... (Read more)

The absorption and emission spectra of silicon nanocrystals up to 1 nm diameter have been calculated within a first-principles framework. Our calculations include geometry optimization and the many-body effects induced by the creation of an electron-hole pair. Starting from hydrogenated silicon... (Read more)

The migration of monovacancies (V⁰) and self-interstitials (I) has been observed in ion-implanted low-doped float-zone silicon by variable-energy positron annihilation spectroscopy. V⁰ and I were created by the in situ implantation of ~20 keV... (Read more)

The formation of hydrogenlike muonium (Mu) has been studied as a function of implantation energy in intrinsic Si, thin films of condensed van der Waals gases (N₂, Ne, Ar, Xe), fused and crystalline quartz, and sapphire. By varying the initial energy of positive muons... (Read more)

Using density-functional theory within the generalized gradient approximation, we show that Si-based heterostructures with 1/4 layer δ doping of interstitial Mn (Mn_int) are half-metallic. For Mn_int concentrations of 1/2 or 1 layer, the states induced in the band... (Read more)

The Stark splitting of a single fourfold degenerate impurity located within the built-in potential of a metal-semiconductor contact is investigated using low temperature transport measurements. A model is developed and used to analyze transport as a function of temperature, bias voltage, and... (Read more)

We have determined silicon self-diffusivity at temperatures 735–875 °C based on the Raman shift of longitudinal optical phonon frequencies of diffusion annealed ²⁸Si/³⁰Si isotope superlattices. The activation enthalpy of 3.6 eV is obtained in such low temperature... (Read more)

We describe how the spin coherence time of a localized electron spin in solids, i.e., a solid state spin qubit, can be prolonged by applying designed electron spin resonance pulse sequences. In particular, the spin echo decay due to the spectral diffusion of the electron spin resonance frequency... (Read more)

Ortho-para conversion of isolated interstitial H₂ in single-crystalline Si is studied by Raman scattering. This process is suggested to be caused by the interaction of H₂ with the nuclear magnetic moment of ²⁹Si. At 77 K the ortho-to-para conversion rate is... (Read more)

We report an ab initio study of the electronic properties of surface dangling-bond (SDB) states in hydrogen-terminated Si and Ge nanowires with diameters between 1 and 2 nm, Ge/Si nanowire heterostructures, and Si and Ge (111) surfaces. We find that the charge transition levels ε(+/-)... (Read more)

Measurement of dissolved chromium concentration in p-type crystalline silicon by means of the change in carrier lifetime due to chromium-boron pair dissociation requires precise knowledge of the recombination parameters of dissolved chromium in silicon. This work, based on quasi-steady-state... (Read more)

The authors previously reported an unusual phenomenon of strain relaxation accompanied by a reduction in threading dislocation density (TDD) on a Si_0.77Ge_0.23 layer grown on top of alternating layers of... (Read more)

The density and spatial distribution of oxide precipitates within a crystalline silicon wafer is of paramount importance for microelectronic device yield. In this letter, the authors show how the formation of previously unconsidered, very small vacancy aggregates can explain macroscopic spatial... (Read more)

The authors present the results of electrically detected magnetic resonance (EDMR) experiments on ion-implanted Si:P nanostructures at 5 K, consisting of high-dose implanted metallic leads with a square gap, in which phosphorus is implanted at a nonmetallic dose corresponding to 10¹⁷ ... (Read more)

The beneficial effects of F implantation on the modification of extended defects in Si have been studied. Preamorphized Si samples were implanted with F (75 keV, 6×10¹⁵ F/cm²) and regrown by solid phase epitaxy (SPE) at 700 °C. The formation, just after SPE, of a... (Read more)

A detailed study of the transformation of the {113} defects into dislocation loops has been carried out in Ge preamorphized silicon (30 keV, 1×10¹⁵ Ge⁺/cm²) and annealed at 800 °C for time ranging from 15 to 2700 s. The presence of a stable defect,... (Read more)

The authors have calculated that fluorine substituting for oxygen gives no gap states in HfO₂. This accounts for the good passivation of oxygen vacancies by F seen experimentally. Bonding arguments are used to account for why F may be the most effective passivant in ionic oxides such as... (Read more)

Fluorine (F) passivation in poly-Si/TaN/HfO₂/p-Si gate stacks through gate ion implantation has been studied. It has been found that when the TaN thickness was less than 15 nm, the mobility and subthreshold swing improved significantly in HfO₂ n-channel... (Read more)

A 1.0 nm silicon nitride (SiN) layer can prevent reaction between HfO₂ and Si completely. In this case, the interface state spectra obtained from x-ray photoelectron spectroscopy measurements under bias have two peaks above and below the midgap, attributable to Si dangling bonds... (Read more)

Deep level manganese (Mn) doping has been used to fabricate very high resistivity single crystal silicon substrates grown by the Czochralski method. The Mn has been introduced by ion implantation with a dose of 10¹⁴ cm^–2 of Mn at 100 keV followed by rapid thermal... (Read more)

Electron spin resonance analysis of (100)Si/LaAlO₃ structures reveals the absence of a Si/SiO₂-type interface in terms of archetypal Si-dangling bond-type Si/SiO₂ interface defects (P_b0,P_b1). With no... (Read more)

The effects of HfSiO nitridation on charge trapping and long-term dielectric reliability are investigated. A comparison between decoupled plasma nitridation, annealing in NH₃, and no nitridation is made. It was found that thinner HfSiO layers show less trapped charge. Decoupled plasma... (Read more)

Low pressure chemical vapor deposition of Si₃N₄ on oxidized Si (111) surfaces causes a change in the properties of the dominant interface defect, the P_b center, observed by electron paramagnetic resonance. The change in the signature of the... (Read more)

Based on ab initio density-functional energetics for saturated (n=2m+2) fluorine-vacancy clusters F_nV_m for m up to 4, the authors set up a model showing that (a) fluorine-vacancy (F–V) aggregates in Si can form in any... (Read more)

Using density functional theory, the interaction of hydrogen with a nitrogen vacancy in -Si₃N₄ is investigated. A single H atom was found to be energetically favorable over non- and doubly protonated vacancies. The traps composed of excess silicon and hydrogen have negative... (Read more)

Shallow fluorine-vacancy (FV) complexes in Si have been directly observed using variable-energy positron annihilation spectroscopy and secondary ion mass spectrometry. The FV complexes, introduced to combat the deactivation and transient-enhanced diffusion of ultrashallow boron, were observed in... (Read more)

Photoluminescence imaging is demonstrated to be an extremely fast spatially resolved characterization technique for large silicon wafers. The spatial variation of the effective minority carrier lifetime is measured without being affected by minority carrier trapping or by excess carriers in space... (Read more)

Synchrotron-based analytical microprobe techniques, electron backscatter diffraction, and defect etching are combined to determine the dependence of metal silicide precipitate formation on grain boundary character and microstructure in multicrystalline silicon (mc-Si). Metal silicide precipitate... (Read more)

Crystal qualities of Si/SiGe/Si-on-insulator structures with different SiGe thicknesses were evaluated by photoluminescence (PL). The wafers were annealed at different temperatures with a ramping rate of 5 °C/min. Free exciton PL peaks were clearly observed for the as-grown wafers and decreased... (Read more)

In this work, the formation of donors in n-type high resistivity magnetic Czochralski-grown silicon wafers, directly exposed to a hydrogen plasma, is investigated by a combination of capacitance-voltage (C-V) and deep level transient spectroscopy (DLTS) measurements.... (Read more)

Hydrogenation by high temperature rapid annealing of SiN_x:H is found to be very effective on the defects responsible for the carrier trapping effect in multicrystalline silicon. The passivation effect is reversible and is annihilated by a long thermal annealing. As for the... (Read more)

Hydrogenated amorphous silicon (a-Si:H) films prepared using a molecular beam deposition (MBD) method show an unusually sharp, narrow infrared absorption peak at 2080–2090 cm^–1, which is thought to result from surface SiH species in the a-Si:H. The sharp, narrow... (Read more)

X-ray topographical images from thin (50 nm) strained-Si films grown on relaxed, planarized crystalline SiGe-on-Si (001) virtual substrates have been imaged by glancing-incidence monochromatic x-ray topography. This extremely asymmetric diffraction geometry, utilizing (311) diffraction planes, can... (Read more)

The electrical properties of dopants in Si are of primary importance for the realization of electronic devices. Indium represents a promising p-type dopant whose electrical properties are improved by codoping with C. From theoretical studies In and C are expected to pair in the Si matrix in... (Read more)

The radiative recombination processes in dislocated float zone silicon samples deformed under gigapascal stresses were studied by photoluminescence (PL) spectroscopy. The observed shuffle dislocations present a reconstructed core and their generation is accompanied by the introduction of point... (Read more)

We have investigated the interface states in HfO₂/SiO₂/Si(100) systems that were prepared by using the in situ pulsed laser deposition technique. X-ray photoelectron spectroscopy data revealed that when the HfO₂ film thickness exceeds 11 Å, the film... (Read more)

We report low-frequency charge noise measurement on silicon substrates with different phosphorus doping densities. The measurements are performed with aluminum single electron transistors (SETs) at millikelvin temperatures where the substrates are in the insulating regime. By measuring the SET... (Read more)

Based on theoretical calculations, we find that at p+ polycrystalline silicon (poly-Si)/HfO₂ gates, Si interstitials are easily migrated from the electrode, forming Hf–Si bonds with a charge transfer to the electrode, and the resulting interface dipole raises the Fermi level... (Read more)

The role of dimerization of atomic hydrogen to give molecular hydrogen in determining negative bias temperature instability (NBTI) kinetics is explored analytically. The time dependency of NBTI involving molecular hydrogen was found to obey a power law with a slope of 1/6, as opposed to the 1/4... (Read more)

The transient properties of single grain–thin film transistors (SG-TFTs) with high electron mobility have been studied. Overshoot current induced by trap states has been observed in most of the devices. A method of ac measurements has been used to investigate the trap processes. Both transient... (Read more)

Defects in silicon nanowires have been investigated using the electron spin resonance (ESR) method. The ESR signals consist of three features: a strong resonance at g=2.002 49, a weak line at g=2.000 48, and a broad feature at g=2.005 41. From the saturation behavior and... (Read more)

We implanted ultralow doses (2×10¹¹ cm^–2) of antimony ions (¹²¹Sb) into isotopically enriched silicon (²⁸Si) and find high degrees of electrical activation and low levels of dopant diffusion after rapid thermal annealing. Pulsed electron spin... (Read more)

A two-dimensional dislocation network artificially embedded in a silicon-on-insulator (SOI) layer was examined as the source of lattice strain to generate a periodic potential. A screw dislocation network with the period of 20 nm was formed in an SOI layer using a twist bonding of two SOI wafers.... (Read more)

An approach to transfer a high-quality Si layer for the fabrication of silicon-on-insulator wafers has been proposed based on the investigation of platelet and crack formation in hydrogenated epitaxial Si/Si_0.98B_0.02/Si structures grown by molecular-beam epitaxy. H-related... (Read more)

The structure of the interface between SiO₂ and Si(100) is investigated using the replica-exchange method driven by classical molecular dynamics simulations based on ab initio-derived interatomic potentials. Abrupt interfaces are shown to be unstable, whereas a substoichiometric... (Read more)

We report on the correlation between paramagnetic defects and the luminescent properties of nanocrystalline silicon (nc-Si) using electron spin resonance (ESR) and photoluminescence measurements. Nanocrystalline silicon having particle sizes from 1.9 to 3.0 nm exhibited continuous luminescence... (Read more)

Nitrogen-doping effects in silicon crystal growth have been theoretically studied using thermodynamical simulation based on first-principles calculation results. The results show that the densities of various complexes are determined in the balance between the enthalpy effects and the entropy... (Read more)

The influence of Hf-based dielectrics on the underlying SiO₂ interfacial layer (IL) in high-k gate stacks is investigated. An increase in the IL dielectric constant, which correlates to an increase of the positive fixed charge density in the IL, is found to depend on the starting,... (Read more)

The dislocation dependence of open circuit voltage is studied based on Donolato's model for the effect of dislocations on minority carrier effective diffusion length [J. Appl. Phys. 84, 2656 (1998)]. Experimental data measured on thin-film solar cells show a strong decrease of open circuit... (Read more)

Outdiffusion profiles of nitrogen, produced by 900 °C annealing and monitored by secondary ion mass spectroscopy, clearly show that the nitrogen community consists of three noninteracting components. The A component (dominant at higher nitrogen concentration) is represented by a species... (Read more)

Schottky contacts on p-type silicon, with embedded arrays of β-FeSi₂ nanocrystallites, were studied by current-voltage (I-V), deep level transient spectroscopy (DLTS), and low-frequency noise measurements. Forward I-V characteristics on logarithmic... (Read more)

We have reported depth and in-plane profiling of strain, Ge composition, and defects in strained-Si/Si_1–xGe_x/Si heterostructures using micro-Raman imaging. Raman profiling in the depth direction was carried out with a depth resolution of ~15 nm using a... (Read more)

Defect centers generated in crystalline silicon by MeV Si implants have been investigated by a combination of photoluminescence, variable-energy positron annihilation measurements, depth profiling by etching, annealing studies, and the dependence on impurities. The broad 935 meV photoluminescence... (Read more)

In 1998, Donolato presented an analytical model describing the effect of dislocation density on minority carrier effective diffusion length [J. Appl. Phys. 84, 2656 (1998)]. While this analysis was derived for a "semi-infinite" specimen, our objective is the appropriate description... (Read more)

Damage accumulation in neon-implanted silicon with fluences ranging from 5×10¹⁴ to 5×10¹⁶ Ne cm^–2 has been studied in detail. As-implanted and annealed samples were investigated by Rutherford backscattering spectrometry under channeling... (Read more)

Micro-Raman spectroscopy and atomic force microscopy investigations have been applied on hydrogen implanted p-type Czochralski silicon samples to investigate the hydrogen related defects and their evolution after subsequent annealing. The thermal evolution of interstitial-hydrogen and... (Read more)

Vacancy-impurity complexes in polycrystalline Si (poly-Si) used as a gate electrode of the metal-oxide-semiconductor field-effect transistor (MOSFET) were probed using monoenergetic positron beams. Doppler broadening spectra of the annihilation radiation and the positron lifetimes were measured for... (Read more)

An internal shrinkage of nanocavity in silicon was in situ observed under irradiation of energetic electron on electron transmission microscopy. Because there is no addition of any external materials to cavity site, a predicted nanosize effect on the shrinkage was observed. At the same time,... (Read more)

The effects of 2 MeV Si⁺ implantation on silicon-on-insulator layers uniformly doped with B at concentrations 1.0 and 1.8×10²⁰ cm^–3, and the kinetics of damage recovery were investigated by carrier density, mobility measurements, and transmission... (Read more)

Infrared (IR) spectroscopy was employed for a thorough study of the C_iC_s(Si_I) defect formed in neutron-irradiated carbon-doped Czochralski silicon material. Its IR signals at 987 and 993 cm^–1, as well as the thermal evolution of the... (Read more)

In this paper, the impact of iron contamination on the conversion efficiency of single-crystalline p-type silicon solar cells is investigated by means of the combination of numerical simulations and experimental data, taking into account the more recent results about the properties of iron in... (Read more)

Electron energy-loss spectroscopy combined with high-angle annular dark-field (HAADF) imaging in scanning transmission electron microscopy was used to investigate the chemistry of interfacial layers in HfO₂ gate stacks capped with polycrystalline Si gate electrodes. To interpret the... (Read more)

Isothermal deep-level transient spectroscopy (DLTS) with a single pulse has been used to study the transformation behavior of hydrogen-related metastable defects labeled EM1 (E_c–0.28 eV) and EM2 (E_c–0.37 eV), which are observed in... (Read more)

The effects of thermal annealing and codoped impurities including carbon, nitrogen, oxygen, and fluorine, on the occupation of erbium lattice locations in Si, have been investigated in detail. Ion channeling measurements indicate that ion-implanted Er can mainly occupy two distinct lattice locations... (Read more)

In this work, we have studied the changes in the optical properties on crystalline silicon implanted wafers (1×10¹³–1×10¹⁶ P⁺/cm²) using an extensive ellipsometric analysis. The effects of implantation energy (20–180 KeV) and... (Read more)

An experimental-analytical technique for the model-independent nondestructive characterization of single-crystal alloys is applied to partially strain-compensated SiGe:C/Si single layer structures with high concentrations of Ge. The studies were performed on pre- and postannealed SiGe:C/Si samples.... (Read more)

The interaction between indium and boron coimplanted in silicon has been investigated. In particular, the effects of the coimplantation on the diffusion and the electrical activation have been studied in comparison with the single B or In implanted samples. It is shown that, by means of... (Read more)

The formation and growth of defects, including nanocavities and extended interstitial-type defects, created by helium implantation in silicon (50 keV, 7.10¹⁵ cm^–2) in the temperature range of 100–550 °C has been investigated by grazing incidence small-angle... (Read more)

While it is known that F modifies dopant diffusion in crystalline Si, the physical mechanisms behind this process are still unclear. In this work we report experimental studies about the F control of the point defect density in preamorphized Si layers. These studies put the basis for the... (Read more)

The effect of hydrogen implantation in silicon single crystals is studied using high-resolution x-ray scattering. Large strains normal to the sample surface are evidenced after implantation. A simple and direct procedure to extract the strain profile from the scattering data is described. A... (Read more)

In this work we perform a systematic study of the dissolution of a dislocation loop layer under the influence of inert SiO₂/Si and nitrogen-rich SiO₂/Si interfaces. The composition of the dislocation loop layer was just after its formation 10%–20% Frank dislocation loops... (Read more)

A quantitative study about the thermal activation of oxygen related thermal donors in high resistivity p-type magnetic Czochralski silicon has been carried out. Thermal donor formation has been performed through isothermal annealing at 430 °C up to a total time of 120 min. Space charge... (Read more)

The effects of x-ray irradiation on the transfer and noise characteristics of excimer-laser-annealed polycrystalline silicon (poly-Si) thin-film transistors (TFTs) have been examined at dose levels up to 1000 Gy. Parameters including mobility, threshold voltage, subthreshold swing, and leakage... (Read more)

The parametrization of our recently proposed model of the Staebler-Wronski effect (SWE) is improved, which leads to an even better agreement with the experimental photoconductivity of light-soaked a-Si:H. The numerical solution of the essential equation exhibits well the typical SWE behavior,... (Read more)

The impact of nitridation on open volumes in thin HfSiO_x films fabricated on Si substrates by atomic layer deposition was studied using monoenergetic positron beams. For HfSiO_x, positrons were found to annihilate from the trapped state due to open volumes which... (Read more)

In He implantation induced cavities highly contaminated with metals (Au, Ni, Pt) we found that, when no three-dimensional structure is observed, the shape of the cavities can be strongly modified depending on the nature of the metal and on its trapped quantity. The equilibrium shape of cavities is... (Read more)

Two different boron- and oxygen-related recombination centers are found to be activated in crystalline silicon under illumination or electron injection in the dark, both leading to a severe degradation in the carrier lifetime. While one center forms on a time scale of seconds to minutes, the... (Read more)

An overview of the evolution of transistor parameters under negative bias temperature instability stress conditions commonly observed in p-MOSFETs in recent technologies is presented. The physical mechanisms of the degradation as well as the different defects involved have been discussed according to a systematic set of experiments with different stress conditions. According to our findings, a physical model is proposed which could be used to more accurately predict the transistor degradation. Finally, based on our new present understanding, a new characterization methodology is proposed, which would open the way to a more accurate determination of parameter shifts and thus allowing implementing the degradation into design rules. (Read more)