Ag Si Research Articles

Stable reverse bias or integrated bypass diode in HIP‑MWT+ solar cells

The Metal Wrap Through+ (HIP-MWT+) solar cell is based on the PERC concept but features two additional electrical contacts, namely the Schottky contact between p-type Si bulk and Ag n-contact and the metal-insulator-semiconductor (MIS) contact on the rear side of the cell below the n-contact pads. To prevent thermal hotspots under reverse bias, both contacts shall either restrict current flow or allow a homogenous current flow at low voltage. In this work we present both options. First the stable reverse bias characteristics up to −15 V with a MIS contact using industrially manufactured SiON passivation and second, an integrated by-pass diode using AlOX as insulator in the passivation stack allowing current flows at approximately Vrev = –3.5 V depending on the chosen screen-print paste. The examined Schottky contacts break down at around Vrev = –2.5 V. Reverse bias testing of the cells reveals a solid performance of the cells under reverse bias and an average conversion efficiency of η = 21.2% (AlOX) and η = 20.7% (SiON), respectively.

Synthesis, Characterisation and Antibacterial Properties of Silicone-Silver Thin Film for the Potential of Medical Device Applications.

Silver (Ag) particles have sparked considerable interest in industry and academia, particularly for health and medical applications. Here, we present the “green” and simple synthesis of an Ag particle-based silicone (Si) thin film for medical device applications. Drop-casting and peel-off techniques were used to create an Si thin film containing 10–50% (v/v) of Ag particles. Electro impedance spectroscopy (EIS), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and tensile tests were used to demonstrate the electrical conductivity, crystallinity, morphology-elemental, and mechanical properties, respectively. The oriented crystalline structure and excellent electronic migration explained the highest conductivity value (1.40 × 10−5 S cm−1) of the 50% Ag–Si thin film. The findings regarding the evolution of the conductive network were supported by the diameter and distribution of Ag particles in the Si film. However, the larger size of the Ag particles in the Si film resulted in a lower tensile stress of 68.23% and an elongation rate of 68.25% compared to the pristine Si film. The antibacterial activity of the Ag–Si film against methicillin-resistant Staphylococcus aureus (MRSA), Bacillus cereus (B. cereus), Klebsiella pneumoniae (K. pneumoniae), and Pseudomonas aeruginosa (P. aeruginosa) was investigated. These findings support Si–Ag thin films’ ability to avoid infection in any medical device application.

Influences of alloying elements and dendritic spacing on the corrosion behavior of Al–Si–Ag alloys

The most important commercial casting alloys are those based on Al–Si. Their technical characteristics are highly connected to their as-cast microstructure, which is translated by the secondary dendrite arm spacing (SDAS). The alloy microstructure has been demonstrated to be changed by the adding of certain alloying elements, in the sense of boosting the desired properties and features. Search has been intensified to provide a positive balance of several properties, such as: high yield strength, high electrical conductivity, and high corrosion resistance, besides maintaining the ability for the alloy to be conventionally solidified. Under such context, both addition of Ag and the control of the fineness of the dendritic structure can be alternatives seeking better properties for Al–Si alloys. In addition to the possibility of application in current studies contributing to the growing development needs as engine materials, Al–Si–Ag alloys can emerge as an alternative to the manufacture of parts for electric vehicles, such as rotors and inverters, where high mechanical strength, corrosion resistance and electrical conductivity are required. Corrosion findings of Al–Si–Ag specimens having quite different SDAS of five alloys are presented here: Al-5wt.% Si, Al-5wt.% Si-0.1wt.% Ag, Al-10wt.% Si-0.1wt.% Ag, Al-5wt.% Si-2wt.% Ag, Al-10wt.%Si-2wt.%Ag alloys. A complete set of characterization with potentiodynamic polarization, electrochemical impedance spectroscopy, immersion tests, optical microscopy and scanning electron microscopy (SEM) was developed for these alloys. It has been demonstrated that increase in the alloy Si content diminishes corrosion resistance, and that increase in Ag content, considering Al-10% Si alloys, reduces corrosion resistance as well, despite creating thicker passive films. Furthermore, the alloys with the lowest Ag content (0.1 wt.%) had the greatest corrosion performance among the Ag-containing alloys, while the microstructure refinement tends to enhance the nobility of the samples.

Formation and properties of biocompatible Ti-based bulk metallic glasses in the Ti–Cu–Zr–Fe–Sn–Si–Ag system

The Ni-free Ti-based bulk metallic glasses (BMGs) with high glass-forming ability (GFA) can be synthesized in the (Ti, Cu, Zr)92.5Fe2.5Sn2Si1Ag2 alloy system over a wide composition range by copper-mold casting. Especially, the Ti48Cu37Zr7.5Fe2.5Sn2Si1Ag2 glassy alloy can form the BMG rod with a diameter up to 6 mm and showed a high compressive strength of ~ 2.05 GPa, elastic modulus of ~ 100 GPa, and microhardness of ~ 571 Hv. The Ti-based BMGs presented good bio-corrosion resistance in a simulated physiological environment attributed to the formation of Ti-, Zr-, Si-, and Fe-enriched passive films. The biocompatibility of the Ti-based glassy alloys was systematically investigated by both indirect cytotoxicity test and direct cell-culture experiments. The Ti-based BMG extracts had no cytotoxic effects on the proliferation of the cells. The good cell adhesion, proliferation, differentiation, and mineralization of bone-forming MC3T3-E1 pre-osteoblasts on the BMGs were parallel to those on the Ti–6Al–4V alloy. These results manifested that the present Ti-based BMGs are promising candidates as biomaterials.

Adsorption characteristics of silver atoms and silver ions on silica surface in silver nanoparticle hydrosol system

Previous studies have demonstrated that silver ions (Ag+) can be released from silver nanoparticles (AgNPs) to produce a system of silver atoms (Ag0) and Ag+ in equilibrium, which may affect the environment through adsorption on sediment. Here, the adsorption behaviour of Ag0 and Ag+ in a AgNP hydrosol system on a silica surface was systematically investigated using experimental evaluation and first-principles calculations based on density functional theory. The adsorption environment and performance were first analysed by batch and fixed-bed experiments, which indicated that less adsorption occurred between silica and silver. Subsequent energy calculations and structural optimisation revealed that both Ag0 and Ag+ were more likely to be chemisorbed on the silica surface through covalent (AgO) bonds. The average adsorption energies of SiO2/Ag+ and SiO2/Ag0 were −5.445 and −3.61 eV, respectively. In addition, Ag0 lost an average of 0.86 electrons to the O4–silica bond. By contrast, only a few electrons, which bonded with O1, were transferred from silica to Ag+. Analyses of the density of states and crystal orbital Hamilton population revealed that O and Ag were hybridised with the 2p–4d orbitals after adsorption. In addition, the peak shifts in the high-resolution Ag 3d, O 1s and Si 2p X-ray photoelectron spectra after adsorption revealed changes in the chemical state. The presence of AgO bonds was confirmed by the surface-enhanced Raman scattering spectrum. Silica was selected as the main component of sediment in this study, and it is hoped that this work will motivate a simulation of the migration and transformation of silver by sediment in the water environment.

Preparation of Novel Ag–Si–TiO2 Composite and Research on Its Photocatalytic Degradation of Formaldehyde

A novel Ag–Si–TiO2 composite was prepared via sol–gel method for removing residual formaldehyde in shiitake mushroom. The structure of Ag–Si–TiO2 composite was characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. Ultraviolet-visible absorption spectroscopy (UV-Vis) and N2 adsorption-desorption tests showed that Ag and Si co-doped decreased the band gap, the Brunauer-Emmett-Teller (BET) specific surface area of the samples increased and the recombination probability of electron-hole pairs (e--h+) reduced. Effect on removal rate of formaldehyde with different Ag-Si co-doped content, formaldehyde concentration and solution pH were investigated, and the results showed that 6.0 wt%Ag-3.0 wt%Si-TiO2 samples had an optimum catalytic performance, and the degradation efficiency reached 96.6% after 40 W 365 nm UV lamp irradiation for 360 min. The kinetics of formaldehyde degradation by Ag–Si–TiO2 composite photocatalyst could be described by Langmuir-Hinshelwood first-order kinetic model.

Light-Trapping SERS Substrate with Regular Bioinspired Arrays for Detecting Trace Dyes.

Recently, few studies have focused on the light-trapping surface-enhanced Raman scattering (SERS) substrate combined with Si micropyramids and Ag (or Au). However, the Si micropyramids possess no ordered period, which not only affects the repeatability of the SERS signal but also affects the theoretical exploration. Here, the ordered micropyramids with strong light-trapping capability were fabricated by utilizing unconventional nanosphere lithography and anisotropy wet etching technique. Then, the Ag nanobowls were assembled on the ordered micropyramids to form the SERS substrate with bioinspired compound-eyes structure by utilizing the liquid-solid interface self-assembly and transfer technique. Especially, the evidence for the contribution of antireflective Si micropyramids to Raman enhancement was first presented. For this bioinspired SERS substrate, the lowest concentration of R6G that can be detected is 10-13 M with the level of a single molecule, and the relative standard deviation (RSD) is 3.68%. Meanwhile, the quantitative analysis and qualitative analysis can be realized. Especially, simultaneous trace detection of four common dyes (R6G, CV, MG, and MB) in food can be realized, suggesting that this SERS substrate will have a good application prospect in the field of optical sensors.

Specific heat, thermal diffusivity, and thermal conductivity of Ag–Si alloys within a wide temperature range of 293–823 K

The laser flash method was employed to explore the heat transfer behaviors of Ag-x at.% Si (where x = 0, 5, 11, 25, 50, 75 and 100) alloys over a wide temperature range from 293 to 823 K. The temperature dependency of specific heat and thermal diffusivity were determined by a differential scanning calorimeter and laser flash equipment. Accordingly, the thermal conductivity of Ag–Si alloys was derived. It is found that the thermal conductivity decreases with increasing temperature. At a certain temperature, there is a sharp decline of thermal conductivity with the rising Si content before it reaches the eutectic composition. The decreasing rate of conductivity with rising Si content reduces when Si content is larger than 11%. The microstructures of Ag–Si alloys reveal that the abnormal thermal conductivity at eutectic composition may be caused by the large amount of phase boundaries.

Dual-purpose surface functionalization of Ti-6Al-7Nb involving oxygen plasma treatment and Si-DLC or chitosan-based coatings

The work presents a detailed study on the diamond-like structures doped with Si atoms and biopolymers-based coatings (chitosan, alginate) enriched with Ag nanoparticles (Ag NPs) deposited on the Ti-6Al-7Nb substrate. Multilayers were obtained by Plasma Enhanced Radio Frequency Chemical Vapour Deposition (PE RF CVD) technique and subsequent deposition of biopolymers by immersion method. The impact of Si atoms and Ag NPs on chemical structure, microstructure, topography, cytotoxicity as well as the hardness and Young modulus of the resulting layers was precisely investigated. The most advantageous conditions of plasma functionalization in RF reactor were the mixture of O2-Ar-NH3 in volume ratio of 10/1/9 in the first stage of functionalization (pre-activation). In the case of Si-DLC coatings (up to ca. 19 at.%) the lower silane flow (4 cm3/min) resulted in significant decrease of surface roughness (up to ca. Ra = 0.71 nm) of modified surfaces and increase of hardness reaching ca. 900 nm depth into surface (up to ca. 16 GPa). The most attractive among biopolymer-based coating on Ti-6Al-7Nb in terms of biological activity was chitosan with Ag NPs (diameter of ca. 25 nm) with additional alginate layer. AFM analysis revealed a uniform distribution of Ag NPs in the chitosan matrix. This contributed to advantageous physicochemical and biological properties assuring proper cell adhesion and proliferation. Noteworthy, the resulting surface functionalization of Ti-6Al-7Nb alloy did not cause significant cytotoxicity in vitro, giving a strong hope for perspective applications in implantology.

Reduced resonance line-width and enhanced figure of merit in Ag/Si/SiO2 nanopillar array sensors

Ag/Si/SiO2 nanopillar array sensors are presented to reduce the line-width and enhance the figure of merit (FOM). In Ag/Si/SiO2 nanopillar arrays, each Ag nanopillar is on top of each Si nanopillar, and each Si nanopillar is on top of each SiO2 nanopillar, which sits on quartz substrates. The simulated results show that the line-width can be as small as 7 nm, 2.4 times narrower than that of the periodic arrays of Ag nanopillars on SiO2 nanopillars, which sit on quartz substrates. This can be attributed to the reduced line-width of the plasmonic lattice resonance (PLR), which is due to the coupling between the localized surface plasmon quadrupole polarization of Ag nanopillars and the diffraction of the periodic arrays. The period of the arrays, the diameter of Ag nanopillars, the thickness of Ag nanopillars, Si nanopillars and SiO2 nanopillars have important effects on the PLR. Benefiting from the narrower line-width, the FOM is enhanced. This provides a possible way to improve the application of plasmonic array sensors.

Catalyst-mediated doping in electrochemical growth of solar silicon

The direct electrochemical reduction of silicon dioxide in molten CaCl2 has been investigated as a promising candidate for alternative production process of solar silicon. Herein, we study a catalyst-mediated doping, which is carried out by introducing dopant precursors like Al2O3, In2O3, and Sb2O3 into the molten CaCl2 during the electrochemical growth of silicon on Ag catalyst. The photoelectrochemical measurement demonstrates controllable p-type or n-type doping, and the photoresponse of doped silicon reaches 1.1±0.4 mA/cm2 under 100 mW/cm2 irradiation. Doping densities, estimated from two-point micro-probe measurements and Mott–Schottky plot analyses range from 1015 to 1016/cm3. Dopant is incorporated through Si–Ag catalyst droplet, which is supported by a high dopant content in Ag catalyst revealed by the elemental mapping of secondary ion mass spectroscopy. The catalyst-mediated doping mechanism is proposed to elucidate the doping level. The liquid droplet is presumed to be under local equilibrium along with significant loss of the dopant from it whereby the doping level becomes a function of the segregation coefficient and the rate constant of the electrochemical reaction.

An effective method to calculate RHEED rocking curves from nanoheteroepitaxial systems

An effective method to calculate RHEED rocking curves from nanoheteroepitaxial systems

Reduction in contact resistivity of Ag thick-film conductor on SiNx-coated Si wafer for solar cell using lead tellurite glass frit

In an application for metallization contact of Ag thick-film conductor onto the SiNx-coated Si wafer for solar cells, we examined the wettability, reactivity, microstructure, and electrical contact of two kinds of glass frits: lead borosilicate and lead tellurite. The lead tellurite frit exhibited superior wettability on Si and higher reactivity with SiNx and formed the thinner glass layer between Ag rich layer and Si for firing the Ag thick-film paste at 750 °C, resulting in better conductive contacts. The contact resistivity of Ag thick-film conductor using lead tellurite glass frit was less than one-tenth of that using lead borosilicate glass frit.

In-situ TEM study of the crystallization sequence in a gold-based metallic glass

The composition Au49Ag5.5Pd2.3Cu26.9Si16.3 (at.%) is of interest as the basis for the development of gold-based bulk metallic glasses for application in jewellery. In-situ heating in transmission electron microscopy (TEM) and differential scanning calorimetry (DSC, both conventional and fast) are used to obtain a comprehensive characterization of the decomposition on heating a melt-spun glass of this composition. Linking TEM with DSC over a range of heating rates 0.083‒2000 K s‒1, allows the sample temperature in the TEM heating stage to be calibrated. On heating up to melting, the glass decomposes in up to four stages: (1) complete transformation to single-phase nanocrystalline (Au,Cu)7Si; (2) grain growth of this phase; (3) precipitation of (Pd,Ag)Si, reducing the supersaturation of silicon in the (Au,Cu)7Si matrix; (4) with the precipitate phase remaining stable, decomposition of the matrix to a mixture of (Au,Ag)8Cu2, AuCu and Cu3Au phases. At all stages, grain diameters remain sub-micrometre; some of the stable nanocrystalline microstructures may themselves be of interest for applications. The characterization of the decomposition can assist in the optimization of the glass composition to improve tarnish-resistance, while retaining adequate glass-forming ability, formability in thermoplastic processing, and resistance to crystallization. For materials in general, the close correlation of in-situ TEM and DSC results should find wide use in characterizing complex transformation sequences.

The impact of semimetal nanoparticles on the conduction of thick glass layer at Ag/Si contact interface

This paper reports on the ohmic contact formed by the conductive glass layer found at the interface of Ag/Si contacts on lowly doped emitter silicon solar cells due to the presence of semimetal nanoparticles. The scanning electron microscopy and scanning transmission electron microscope analyses revealed an interface glass layer (IGL) thickness of greater than 380 nm, which was enriched with micro-sized alloys composed of semimetal nanoparticles. This IGL was conductive as confirmed by conductive atomic force microscopy (C-AFM). The presence of these semimetal nanoparticles, identified as Ag2Te and PbTe, was both endowed with low bandgap energies as confirmed by Raman spectroscopy and energy dispersive x-ray spectroscopy. These semimetal nanoparticles were found only in the IGL and formed a “bridge” to connect the Ag gridline and Si emitter for carrier transport. Based on the modified Fowler–Nordheim tunneling process, the modeled C-AFM I–V characteristic curve showed a barrier height of 0.1 eV corresponding to an IGL thickness of only 18 nm. Thus, the carrier transport mechanism “through the conductive bridge” was formed by the semimetal nanoparticles embedded in the IGL. Therefore, the high conductivity of the interface glass led to the specific contact resistance to be independent of the emitter peak doping concentration.

Specific heat of ternary Ag–Si–Ge alloys from 123 K to high temperatures: experiment and prediction

The knowledge of specific heat for Ag–Si–Ge alloys in a broad temperature range would facilitate their practical applications in various branches of engineering. In this work, differential scanning calorimetry measurements were executed to determine specific heat of Ag–Si–Ge alloys from 123 K to high temperatures. For binary alloys, distinct troughs of specific heat are observed at eutectic Ag89Si11 and Ag75Ge25, when temperatures are larger than 500 K. Furthermore, specific heat of ternary Ag–Si–Ge alloys was predicted by four candidate principles based on the binary alloy’s data. Accordingly, the specific heat of 15 compositions of ternary Ag–Si–Ge alloys was determined to evaluate the predicted value. It is found that specific heat increases linearly with the rising Ag and Ge content in Si-rich alloys at low temperatures. Besides, alloys around Si–Ag75Ge25 pseudobinary line in Ag-rich area exhibit much lower specific heat at high temperatures. According to the comparison between measured and predicted specific heat of ternary alloys, the interpolation which employs data of pure elements, hypo-/hypereutectic alloys and the eutectic points, provides highest accuracy, especially at high temperatures. This rule may be applied to other eutectic systems.

Experimental investigation and thermodynamic modeling of the Cu–Ag–Si ternary system

The phase equilibria of the Cu–Ag–Si system were investigated by a combination of key experiments and thermodynamic modeling. Eighteen ternary alloys were prepared to determine the isothermal sections at 500, 600, and 700 °C of the Cu–Ag–Si system by means of X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). The solubilities of Ag in the Cu19Si6, Cu15Si4, Cu56Si11, and hcp(CuSi) phases were measured. No ternary compound was found in this isothermal sections. Based on the experimental equilibria data from the present work, thermodynamic assessment of the Cu–Ag–Si system was carried out by the CALPHAD (CALculation of PHAse Diagrams) approach. The solution phases (Cu), (Ag), (Si), and hcp(CuSi) were described using substitutional solution model and the binary phases Cu19Si6, Cu15Si4, and Cu56Si11 with the solubility of Ag were modeled by the sublattice models. A set of self-consistent thermodynamic parameters of the Cu–Ag–Si system was obtained. The isothermal sections at 500, 600, 650, and 700 °C, vertical sections at 10 and 20 at.% Ag, and liquidus projection were calculated. The reaction scheme of the Cu–Ag–Si system was constructed. The calculated results are in agreement with the experimental data from the present work and literature.

In-Situ TEM Study of the Crystallization Sequence in a Gold-Based Metallic Glass

The composition Au49Ag5.5Pd2.3Cu26.9Si16.3 (at.%) is of interest as the basis for the development of gold-based bulk metallic glasses for application in jewellery. In-situ heating in transmission electron microscopy (TEM) and differential scanning calorimetry (DSC, both conventional and fast) are used to obtain a comprehensive characterization of the decomposition on heating a melt-spun glass of this composition. Linking TEM with DSC over a range of heating rates 0.083‒2000 K s‒1, allows the sample temperature in the TEM heating stage to be calibrated. On heating up to melting, the glass decomposes in up to four stages: (1) complete transformation to single-phase nanocrystalline (Au,Cu)7Si; (2) grain growth of this phase; (3) precipitation of (Pd,Ag)Si, reducing the supersaturation of silicon in the (Au,Cu)7Si matrix; (4) with the precipitate phase remaining stable, decomposition of the matrix to a mixture of (Au,Ag)8Cu2, AuCu and Cu3Au phases. At all stages, grain diameters remain sub-micrometre; some of the stable nanocrystalline microstructures may themselves be of interest for applications. The characterization of the decomposition can assist in the optimization of the glass composition to improve tarnish-resistance, while retaining adequate glass-forming ability, formability in thermoplastic processing, and resistance to crystallization.

Development of PC based automation of ion beam analysis and ion implantation experiments

This paper presents the details of a personal computer (PC) based automation of ion beam analysis and ion implantation experimental setup that has been developed and implemented in a 1.7 MV Tandetron accelerator. Hardware and software of the PC automated system were designed to automate multiple sample ion implantation, standard Rutherford Backscattering spectrometry (RBS), and High resolution Rutherford Backscattering spectrometry (Hi-RBS) experiments. The system uses in-house developed signal conditioning circuitry, isolation amplifiers, and transistor drivers along with cost-effective and off-the-shelf commercial components like a general purpose, multifunction data acquisition card, etc. A five axis goniometer is used for handling multiple samples and their automatic positioning according to the commands from the PC over RS232 interface. Key tasks carried out in the automation of system include control and mesurement of ion beam fluence, selection of backscattered particles through screening of their energies by controlling a set of +/−25 kV and −3 kV high voltage power supplies, controlled collection of backscattered yield using single and multi channel analysers, controlling the region-of-interest windows in the energy spectra and the cumulative counts in them. Controlling the position of the samples and facilitating the experiments on multiple samples, online display of energy spectra and its auto storage, and vacuum interlocking are also automatically done. This PC based setup has been automated using a windows based LabVIEW software making it easy to port the set up between different computer operating systems apart from achieving many other advantages like quick and easy development of versatile, multi-purpose, and user friendly graphical interface. Extensive tests carried out on the hardware established correct functioning of various modules of the hardware. The 0–10 V control inputs applied to the +/−25 kV and −3 kV high voltage power supplies were tested and seen providing an <0.1% accuracy, <0.05% linearity, very low drift of 50 ppm, 0.01% precision, and <1mv rms output noise. The software modules have been tested to check independent control and monitoring the irradiated dose, energy to voltage conversion, the multi channel analyser control in addition to other tasks such as computing the region-of-interest counts. The fluence computed from the pulse counts from the ion beam current integrator and the actual fluence were found to be matching within 0.1%. The vacuum interlocking scheme was tested covering a range of 10−5 mbar to 10−9 mbar. Hi-RBS was carried out on a 3 nm thick Ag film grown on Si substrate using 0.3 MeV H+ ion beam over a backscattered energy range of 10–300 keV for a fixed ion fluence 2 × 1012 ions/cm2 at each energy. The recorded spectrum showed well separated Si edge and Ag peaks. The energy resolution is calculated to be 1.2 keV and a relative energy resolution (ΔE/E) of ∼0.4% is obtained.

Light formation mechanisms induced by well-aligned sub-20-nm Ag quantum dots produced alongside patterned porous Si walls and bottoms

Sub-20-nm Ag nanoparticles created via sputtering were freely moved into preformed Si pores and were arranged along both wall and lower surfaces in etched Si layers via a post-thermal annealing treatment. The variously sized Ag quantum dots on the porous Si facilitate broadband visible emission via photo-generated enhanced luminescent effects, i.e., plasmonic effects of Ag nanoparticles by electron transfer from the Si-based matrix to the metallic Ag. The emission wavelengths and intensities, depending on the sizes of the Ag quantum dots, were determined by the degree of oxidation of the Si-based substrate such as Si, SiOx, and SiO2, according to different post-thermal annealing conditions. The morphological, microstructural, and optical evolution of Ag nanoparticles and Si pores were simply observed via side-cross-sectional scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and crystalline-controlled photoluminescence analyses, respectively. The origin of a new systematic luminescence mechanism based on energy-equilibria is also presented.