Equilibrium Solid Solubility Research Articles

Structural changes in Ge1−xSnx and Si1−x−yGeySnx thin films on SOI substrates treated by pulse laser annealing

Ge1−xSnx and Si1−x−yGeySnx alloys are promising materials for future opto- and nanoelectronics applications. These alloys enable effective bandgap engineering, broad adjustability of their lattice parameter, exhibit much higher carrier mobility than pure Si, and are compatible with the complementary metal-oxide-semiconductor technology. Unfortunately, the equilibrium solid solubility of Sn in Si1−xGex is less than 1% and the pseudomorphic growth of Si1−x−yGeySnx on Ge or Si can cause in-plane compressive strain in the grown layer, degrading the superior properties of these alloys. Therefore, post-growth strain engineering by ultrafast non-equilibrium thermal treatments like pulse laser annealing (PLA) is needed to improve the layer quality. In this article, Ge0.94Sn0.06 and Si0.14Ge0.8Sn0.06 thin films grown on silicon-on-insulator substrates by molecular beam epitaxy were post-growth thermally treated by PLA. The material is analyzed before and after the thermal treatments by transmission electron microscopy, x-ray diffraction (XRD), Rutherford backscattering spectrometry, secondary ion mass spectrometry, and Hall-effect measurements. It is shown that after annealing, the material is single-crystalline with improved crystallinity than the as-grown layer. This is reflected in a significantly increased XRD reflection intensity, well-ordered atomic pillars, and increased active carrier concentrations up to 4 × 1019 cm−3.

Crack‐Free Tungsten Fabricated via Laser Powder Bed Fusion Additive Manufacturing

AbstractAdditive manufacturing of tungsten (W) is challenging due to its high melting point, high thermal conductivity, oxidation tendency, and brittleness from grain boundary (GB) oxides. In this study, the processing of W through laser powder bed fusion is investigated. Parts are fabricated under argon (Ar) and nitrogen (N2) atmospheres using the same processing parameters. The part produced in Ar has cracks with oxide precipitates decorating the fractured GBs. On the other hand, crack‐free W samples are produced under N2 atmosphere without any additional process modification. In both cases, the oxygen (O) content in the LPBF samples is similar to the starting powder. Interestingly, the analysis of the samples fabricated in nitrogen suggests that nitrogen is retained beyond the equilibrium solid solubility limit, while high‐resolution electron micrographs of fractured surfaces reveal reduced levels of oxides at GBs. Increased hardness for samples processed under N2 atmosphere is observed. Density Functional Theory (DFT) calculations performed to study the influence of interstitial nitrogen on oxygen diffusion in W indicated a hindrance to O diffusion from the presence of dissolved N.

Comprehensive investigation on physical, structural, mechanical and nuclear shielding features against X/gamma-rays, neutron, proton and alpha particles of various binary alloys

In this study, four alloys composed of highly pure elements (lead, zinc, tin and bismuth), named Pb–Zn50, Pb–Sn50, Sn–Zn50 and Sn–Bi50 were prepared by rapid solidification process (RSP) using melt-spun technique. The structural, mechanical properties (elastic and plastic deformations), and microhardness have been investigated and analyzed using X-ray diffraction, tensile test machine, and vickers microhardness respectively. According to results, the yield strength, ultimate tensile strength (UTS), toughness, and Vickers hardness (Hv) were improved due to the advantages of rapid solidification technology including elimination of grain boundary segregation, improvement in alloy homogeneity, refinement of grain size, formation of novel metastable crystalline, rises in the equilibrium solid solubility's of solute elements and reduction in the degree of order. This can be ascribed to reinforcement of Zn and Bi particles, refined β-Sn, Zn and Bi grains that could obstruct the dislocation slipping. In addition, the shielding performance of these alloys for gamma radiation were examined and analyzed utilizing WinXCom software over energy range 0.015–15 MeV. The alloys under study found to be good shielding materials against γ-ray relative to common shielding materials and newly studied materials. The results indicate that the Sn–Bi50 alloy has the highest values of μm, Zeff and Zeq ranging from 0.039 to 81.3 cm2/g, 60.41–73.83, and 64.02–70.793 respectively. While it has the smallest values of HVL (ranging from 8.73E-4 to 1.86 cm) which means that it is the best choice as a γ-ray shielding material. In aspects of neutron attenuation characteristics, the results also indicate that the Pb–Zn50 alloy has the highest value of ΣR (0.133 cm−1) amongst all other alloys, frequently used neutron shielding materials, and recently studied materials. Furthermore, proton (H+1) and alpha particles (He+2) projected range (PR) and mass stopping power (MSP) values have been calculated. It can be concluded that Zn–Pb alloy among the examined samples is superior in terms of shielding against proton and alpha particles. This paper provides a comprehensive examination of the use of lead and the development of new safety lead-free shielding materials in many applications including nuclear medicine.

Electrical and Optical Doping of Silicon by Pulsed-Laser Melting

Over four decades ago, pulsed-laser melting, or pulsed-laser annealing as it was termed at that time, was the subject of intense study as a potential advance in silicon device processing. In particular, it was found that nanosecond laser melting of the near-surface of silicon and subsequent liquid phase epitaxy could not only very effectively remove lattice disorder following ion implantation, but could achieve dopant electrical activities exceeding equilibrium solubility limits. However, when it was realised that solid phase annealing at longer time scales could achieve similar results, interest in pulsed-laser melting waned for over two decades as a processing method for silicon devices. With the emergence of flat panel displays in the 1990s, pulsed-laser melting was found to offer an attractive solution for large area crystallisation of amorphous silicon and dopant activation. This method gave improved thin film transistors used in the panel backplane to define the pixelation of displays. For this application, ultra-rapid pulsed laser melting remains the crystallisation method of choice since the heating is confined to the silicon thin film and the underlying glass or plastic substrates are protected from thermal degradation. This article will be organised chronologically, but treatment naturally divides into the two main topics: (1) an electrical doping research focus up until around 2000, and (2) optical doping as the research focus after that time. In the first part of this article, the early pulsed-laser annealing studies for electrical doping of silicon are reviewed, followed by the more recent use of pulsed-lasers for flat panel display fabrication. In terms of the second topic of this review, optical doping of silicon for efficient infrared light detection, this process requires deep level impurities to be introduced into the silicon lattice at high concentrations to form an intermediate band within the silicon bandgap. The chalcogen elements and then transition metals were investigated from the early 2000s since they can provide the required deep levels in silicon. However, their low solid solubilities necessitated ultra-rapid pulsed-laser melting to achieve supersaturation in silicon many orders of magnitude beyond the equilibrium solid solubility. Although infrared light absorption has been demonstrated using this approach, significant challenges were encountered in attempting to achieve efficient optical doping in such cases, or hyperdoping as it has been termed. Issues that limit this approach include: lateral and surface impurity segregation during solidification from the melt, leading to defective filaments throughout the doped layer; and poor efficiency of collection of photo-induced carriers necessary for the fabrication of photodetectors. The history and current status of optical hyperdoping of silicon with deep level impurities is reviewed in the second part of this article.

The influence of post-weld tempering temperatures on microstructure and strength in the stir zone of friction stir welded reduced activation ferritic/martensitic steel

Abstract Reduced activation ferritic/martensitic (RAFM) steels are among the most competitive candidates of structural materials for nuclear fusion reactors, due to their superior comprehensive properties. Friction stir welding (FSW) was investigated in joining RAFM steel, considering its potential advantages in obtaining an optimal microstructure and mechanical properties of welded joint. To evaluate the feasibility of FSW in joining RAFM steel, an in-depth understanding of the microstructure-property relationships for friction stir welded joints of RAFM steel is necessary. In this research, the quantitative relationships between microstructural evolution and tensile properties in the stir zone (SZ) of friction stir welded RAFM steel after post-weld tempering treatment (PWTT) were systematically studied. Three different post-weld tempering temperatures namely 720 °C, 760 °C, and 800 °C were adopted. Then the uniaxial tensile properties were tested at room temperature and 550 °C, respectively. Electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and the Thermo-Calc Calphad software were adopted to systematically investigate the microstructural evolution. Martensite lath width, precipitate number density, equilibrium solid solubility of alloying elements in the matrix, and geometrically necessary dislocation (GND) density were analyzed quantitatively. With the results obtained, we assessed the contribution of each strengthening mechanism to the 0.2% offset yield strength. According to the effective inter-barrier spacing theory, a microstructure-sensitive yield strength model was obtained to well predict the change in yield strength at different conditions. Finally, the results calculated by equivalent strengthening effect indicated that the crucial microstructure determining the yield strength of the SZ for RAFM steel after PWTT is the high density of dislocation substructures.

Non-equilibrium solid-phase growth of amorphous GeSn layer on Ge-on-insulator wafer induced by flash lamp annealing

The effect of flash lamp annealing on the crystal growth of amorphous germanium-tin (GeSn) layer deposited on Ge-on-insulator wafer was investigated. It was found that the presence of Sn in the amorphous Ge significantly promoted solid-phase growth (SPG). The diffusion of Sn during the SPG of GeSn was completely suppressed owing to milli-second thermal processing, providing a high-quality GeSn layer with Sn content of 13%, which far exceeds the equilibrium solid solubility limit (∼1%). The fabricated GeSn/Ge-on-insulator wafer exhibited improved infrared absorption beyond 2000 nm, which would be a suitable platform for near-infrared image sensors based on group-IV materials.

Nanomechanical properties of mechanically alloyed and spark plasma sintered W-nanoparticulate dispersed Cu-Nb alloys

Present study concerns strengthening of nanocrystalline Cu-Nb (1.0 at.%) matrix through addition of W using ball milling at cryogenic temperature. Nb and W has low equilibrium solid solubility in Cu, hence powder blend was subjected to non-equilibrium alloying. The studies shows that 1 at.% Nb could be dissolved into the Cu solid solution, after mechanical alloying for eight hours of cryo-milling. However, W did not form a solid solution even after eight hours of mechanical alloying. The stabilization of the metastable grains by segregation of large size solute atoms along grain boundaries, was attributed to Orowan strengthening of alloys.

The effect of Co addition on the modulated structure coarsening and discontinuous precipitation growth kinetics of Cu–15Ni–8Sn alloy

To understand the effect of Co addition on the modulated structure coarsening and discontinuous precipitation (DP) growth kinetics of Cu–15Ni–8Sn alloy, the experiments are carried out using optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscopy (TEM). Our results showed that the addition of Co in Cu–15Ni–8Sn alloy did not recover with a new second-phase associated with Co. During the aging treatment process, the addition of Co reduced the coarsening kinetics of the modulated structure, which was related to the equilibrium solid solubility (Xe) of Ni and Sn in Cu, diffusion coefficient of Ni and Sn in Cu (D), and to the interfacial energy (σ) of α-Cu matrix/L12. The decrease in values of Xe, D and σ were resulted in a slowdown of the coarsening kinetics. Further, the suitable addition of Co significantly inhibited the nucleation and growth of discontinuous precipitation (DP). The growth kinetics of DP for Cu–15Ni–8Sn-xCo alloy were evaluated using the Johnson-Mehl-Avrami-Kolmogorov equation. With the combination of the Arrhenius equation, the activation energies (Q) of the samples were 105.45 kJ/mol, 150.76 kJ/mol, 178.44 kJ/mol, 251.53 kJ/mol, and 148.89 kJ. Compared with cobalt-free alloy, cobalt-containing alloys exhibited greater activation energy, which suggested that the addition of Co can greatly inhibit the formation of DP. Furthermore, the addition of Co led to decrease in the thickness of the grain boundary and increase in the interlamellar spacing of the DP, which were considered to be the main reasons for suppressing the growth of DP.

Synergistic effect of Nb and Zr addition in thermal stabilization of nano-crystalline Cu synthesized by ball milling

Present study concerns strengthening of nanocrystalline Cu-matrix by binary and ternary addition of Zr (0.5 at. %) and Nb (1.0 at. %) using ball milling at cryogenic temperature. Zr and Nb having low equilibrium solid solubility in Cu, thus powder blends were subjected non-equilibrium alloying. Mechanically alloyed samples were annealed at different temperatures (600–900 °C) for one hour. Stability of the nanocrystalline Cu-matrix even after annealing at 900 °C is attributed to the stabilization of nanocrystalline grains by segregation of larger solute atoms (Nb and Zr) along grain boundaries and/or Zener pinning by precipitates like Cu5Zr in Cu-Zr intermetallics.

Direct-indirect GeSn band structure formation by laser Radiation: The enhancement of Sn solubility in Ge

Low equilibrium solid solubility of Sn atoms in Ge (less than 1%) leads to limitations in application of this material for IR detectors and emitters. Providing of non-equilibrium conditions by powerful pulsed laser radiation can be successfully applied for enhancement of solubility of impurity atoms in the host material. Here we present laser-induced monotonous redistribution of Sn atoms in Ge, based on the thermogradient effect aiming overcoming equilibrium limitations in the solubility. We applied pulsed nanosecond laser radiation to epitaxial Ge0.96Sn0.04 layer grown on Si substrate to increase Sn atomic concentration up to 14% at the surface layer. As a result, indirect-direct graded bandgap GeSn structure was formed. The TEM/EDS cross-section analysis, X-ray photoelectron spectroscopy, Raman and UV reflection spectra confirmed the increase of Sn atomic content at the surface by order of magnitude. SEM and AFM imaging provided evident microstructure changes, while carrier lifetime changes, determined by differential transmittivity, were not observed, indicating that laser irradiation does not generate defects which reduce electronic quality of the material.

Surface segregated Ga, In, and Al activation in high Ge content SiGe during UV melt laser induced non-equilibrium solidification

The impact of solidification front velocity (SFV) on dopant segregation and activation surpassing the equilibrium solid solubility limit was investigated in high Ge content SiGe using UV nanosecond melt laser annealing (MLA). We first simulated the SFV evolution in the MLA-induced solidification of a SiGe binary system. It was then combined with the near-surface atomic and electrically active dopant concentrations measured in the Ga, In, and Al-implanted SiGe after MLA. Solute trapping phenomenon and self-compensation effect of the dopants were discussed to capture a part of their segregation and activation dynamics in the presented SiGeX ternary systems.

Nanoscale n++-p junction formation in GeOI probed by tip-enhanced Raman spectroscopy and conductive atomic force microscopy

Ge-on-Si and Ge-on-insulator (GeOI) are the most promising materials for the next-generation nanoelectronics that can be fully integrated with silicon technology. To this day, the fabrication of Ge-based transistors with a n-type channel doping above 5 × 1019 cm−3 remains challenging. Here, we report on n-type doping of Ge beyond the equilibrium solubility limit (ne ≈ 6 × 1020 cm−3) together with a nanoscale technique to inspect the dopant distribution in n++-p junctions in GeOI. The n++ layer in Ge is realized by P+ ion implantation followed by millisecond-flashlamp annealing. The electron concentration is found to be three times higher than the equilibrium solid solubility limit of P in Ge determined at 800 °C. The millisecond-flashlamp annealing process is used for the electrical activation of the implanted P dopant and to fully suppress its diffusion. The study of the P activation and distribution in implanted GeOI relies on the combination of Raman spectroscopy, conductive atomic force microscopy, and secondary ion mass spectrometry. The linear dependence between the Fano asymmetry parameter q and the active carrier concentration makes Raman spectroscopy a powerful tool to study the electrical properties of semiconductors. We also demonstrate the high electrical activation efficiency together with the formation of ohmic contacts through Ni germanidation via a single-step flashlamp annealing process.

Segregation and activation of Ga in high Ge content SiGe by UV melt laser anneal

The feasibility of dopant activation surpassing the equilibrium solid solubility limit by using an out of equilibrium melt laser annealing (MLA) process was investigated. To that end, we used an UV excimer nanosecond laser annealing and studied the segregation and activation of dopants in a Ga-implanted SiGe 50% epilayer. Dopant segregation is of great interest for future nodes to further improve contact resistivity in transistors. However, there is a lack of in-depth study about their activation. In this paper, we first reported very high Ga activation well above the equilibrium solid solubility limit when the partial Si0.5Ge0.5:Ga melt regime was assessed. The dopant segregation phenomenon, together with the surface morphology change of the Si0.5Ge0.5:Ga epilayer, was then induced by MLA. A very clear honeycomblike surface pattern was observed in the full Si0.5Ge0.5:Ga melt regime, while it was less pronounced in the partial melt regime. This honeycomblike pattern would be the result of dopant precipitation at the liquid–solid interface during solidification. Our simulation results highlighted that solidification velocity could play a key role in the substitutional incorporation of Ga atoms in a SiGe lattice.

Superconductivity in single-crystalline aluminum- and gallium-hyperdoped germanium

Superconductivity in group IV semiconductors is desired for hybrid devices combining both semiconducting and superconducting properties. Following boron doped diamond and Si, superconductivity has been observed in gallium doped Ge, however the obtained specimen is in polycrystalline form [Herrmannsd\"orfer et al., Phys. Rev. Lett. 102, 217003 (2009)]. Here, we present superconducting single-crystalline Ge hyperdoped with gallium or aluminium by ion implantation and rear-side flash lamp annealing. The maximum concentration of Al and Ga incorporated into substitutional positions in Ge is eight times higher than the equilibrium solid solubility. This corresponds to a hole concentration above 10^21 cm-3. Using density functional theory in the local density approximation and pseudopotential plane-wave approach, we show that the superconductivity in p-type Ge is phonon-mediated. According to the ab initio calculations the critical superconducting temperature for Al- and Ga-doped Ge is in the range of 0.45 K for 6.25 at.% of dopant concentration being in a qualitative agreement with experimentally obtained values.

Influence of thermal annealing on the electrical and luminescent properties of heavily Sb-doped Ge/Si(001) layers

In this paper, we report on the formation of heavily n-doped Ge:Sb layers on Si(001) substrates by MBE with active dopant concentration exceeding 1020 cm−3 and discuss their thermal stability. Rapid thermal annealing was applied to the samples with different doping densities being both below and above the equilibrium solubility limit of Sb in Ge. Experimentally obtained changes of the impurity atomic concentration and carrier density were attributed to Sb bulk diffusion, desorption and dopant clustering. The qualitatively different modifications of room-temperature photoluminescence (PL) due to annealing were obtained for the n-Ge layers with different doping levels. In particular, for the doping levels which were below or close to the equilibrium solid solubility the overall positive impact of annealing on the PL intensity was observed. However, for the n-Ge layers with higher doping levels a more complex behavior was obtained, namely, a significant drop followed by the subsequent partial restoration of the PL intensity with the increase of annealing temperature. Changes of the PL response were attributed to the two main processes which occur during thermal treatment—annealing of the point defects generated due to low-temperature growth of a doped layer and dopant cluster formation—which have the opposite impact on the PL intensity. The obtained results allowed us to formulate the recommendations on thermal treatment of the n-type doped Ge layers, which may be useful for Ge-based Si photonics applications.

CMOS‐Compatible Controlled Hyperdoping of Silicon Nanowires

AbstractHyperdoping consists of the intentional introduction of deep‐level dopants into a semiconductor in excess of equilibrium concentrations. This causes a broadening of dopant energy levels into an intermediate band between the valence and the conduction bands. Recently, bulk Si hyperdoped with chalcogens or transition metals is demonstrated to be an appropriate intermediate‐band material for Si‐based short‐wavelength infrared photodetectors. Intermediate‐band nanowires can potentially be used instead of bulk materials to overcome the Shockley–Queisser limit and to improve efficiency in solar cells, but fundamental scientific questions in hyperdoping Si nanowires require experimental verification. The development of a method for obtaining controlled hyperdoping levels at the nanoscale concomitant with the electrical activation of dopants is, therefore, vital to understanding these issues. Here, this paper shows a complementary metal‐oxide‐semiconductor (CMOS)‐compatible technique based on nonequilibrium processing for the controlled doping of Si at the nanoscale with dopant concentrations several orders of magnitude greater than the equilibrium solid solubility. Through the nanoscale spatially controlled implantation of dopants, and a bottom‐up template‐assisted solid phase recrystallization of the nanowires with the use of millisecond‐flash lamp annealing, Se‐hyperdoped Si/SiO2 core/shell nanowires are formed that have a room‐temperature sub‐bandgap optoelectronic photoresponse when configured as a photoconductor device.

Precipitation behavior of Ti in high strength steels

Precipitation behavior of Ti in high strength steels was investigated by means of the equilibrium solid solubility theory. The contributions of Ti content to yield strength were calculated. The calculated results were verified by the hot rolling experiment for C–Mn steel and C–Mn–Ti micro alloyed steel, respectively. The research results show that the precipitates are mainly TiN at the higher temperature. With the decreasing temperature, the proportion of TiC in precipitates increases gradually. When the temperature drops to 800 °C, TiC will become predominant for the precipitation of Ti. When Ti content is less than 0.014% (mass fraction), Ti has little influence on the yield strength. When Ti content is in the range of 0.014%–0.03% (mass fraction), the yield strength of Ti micro alloyed steel is greatly increased, which leads to instability of the mechanical properties of the steel. Therefore, the design of Ti content in high strength steels should avoid this Ti content range. When Ti content is higher than 0.03%, the yield strength increases stably. In this experiment, when added Ti content was controlled in the range of 0.03%–0.05%, the contribution to the yield strength of Ti micro alloyed steel can reach about 92.44 MPa.

Low-temperature (<200 oC) solid-phase crystallization of high substitutional Sn concentration (∼10%) GeSn on insulator enhanced by weak laser irradiation

Low temperature (<200 oC) crystallization of GeSn (substitutional Sn concentration: >8%) on insulating substrates is essential to realize next generation flexible electronics. To achieve this, a growth method of high quality GeSn films on insulating substrates by combination of laser irradiation and subsequent thermal annealing is developed. Here, the laser fluence is chosen as weak, which is below the critical fluence for crystallization of GeSn. It is clarified that for samples irradiated with weak laser fluence, complete crystallization of GeSn films is achieved by subsequent thermal annealing at ∼170 oC without incubation time. In addition, the quality of GeSn films obtained by this method is higher compared with conventional growth techniques such as melting growth by pulsed laser annealing or solid-phase crystallization (SPC) without pre-laser irradiation. Substitutional Sn concentrations in the grown layers estimated by Raman spectroscopy measurements are 8-10%, which far exceed thermal equilibrium solid-solubility of Sn in Ge (∼2%). These phenomena are explained by generation of a limited number of nuclei by weak laser irradiation and lateral SPC by subsequent thermal annealing. This method will facilitate realization of next-generation high performance devices on flexible insulating substrates.

Effect of Nb, Y and Zr on thermal stability of nanocrystalline Al-4.5 wt.% Cu alloy prepared by mechanical alloying

In the present study, effect of Nb, Y and Zr (having low equilibrium solid solubility in Al) in the formation of nanocrystalline Al-4.5 wt.% Cu-1at.% X (X = Nb, Y & Zr) solid solutions by mechanical alloying and their thermal stability have been investigated. The mechanically alloyed samples were annealed in batches for 1 h at different temperatures ranging from 150 to 550 °C. The thermal stability has been studied through X-ray diffraction (XRD) phase analysis and variation of microhardness as a function of temperature. Transmission electron microscopy (TEM) and SAED analysis showed that 1 at.% Y and 1 at.% Nb could be dissolved into Al-4.5% Cu solid solutions after mechanical alloying up to 8 h of milling. The spontaneity of formation of Al-4.5%CuY, Al-4.5%CuNb and Al-4.5%CuZr solid solutions has been explained from the change of Gibbs free energy as per Miedema's and Toop's models. It demonstrated that the summative energy due to the reduction in crystallite size and accumulation of dislocation density exceeds the theoretical energy barrier required for the formation of the Al-4.5%CuY, Al-4.5%CuNb disordered solid solutions. The grain sizes were found to retain <100 nm even after annealing at 550 °C. This is attributed to the stabilization of metastable grains by segregation of large size solute atoms (Nb, Y and Zr) along grain boundaries and/or Zener pinning by intermetallic precipitates like Al3Nb in Al CuNb, Al3Y and Al3Y5 in AlCuY and Cu10Zr7, Al3Zr and Cu5Zr in AlCuZr alloys.

Solid-phase crystallization of Si1−x−ySnxCy ternary alloy layers and characterization of their crystalline and optical properties

The solid phase crystallization of Si1−x−ySnxCy ternary alloy layers on an insulator has been examined. Amorphous Si1−x−ySnxCy layers with a Sn content of 0–20% and a C content of 0–10% were deposited on quartz substrates using a radio-frequency magnetron sputtering method and annealed at temperatures from 400 to 800 °C to induce the solid-phase crystallization. The crystalline properties of the Si1−x−ySnxCy layers and the influences of Sn and C introduction on their crystalline structures were investigated. It was found that Sn introduction effectively reduces the crystallization temperature of a Si1−x−ySnxCy layer to 400 °C, while a Si1−yCy binary alloy layer is hardly crystallized even at 800 °C. In addition, X-ray photoelectron spectroscopy measurement revealed that the Sn introduction effectively enhances the introduction of C atoms into substitutional sites in the ternary alloys. The substitutional C content in a polycrystalline Si1−x−ySnxCy layer was estimated to be as high as 7.2%, which exceeds the thermal equilibrium solid solubility of C in a Si matrix. The absorption spectra of Si1−x−ySnxCy ternary alloys were also investigated.