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In this study, a SiO2 layer containing YF3:Yb3+/Er3+ phosphors was deposited within matrix-grooves on the back side of silicon solar cells to enable the up-conversion (UC) of near-infrared (NIR) wavelengths with the aim of enhancing energy conversion efficiency. The chemical and optical characteristics of the UC layer were identified using energy-dispersive X-ray spectroscopy and photoluminescence measurements. We also characterized the electrical and optical performance of cells featuring a SiO2 layer with and without NIR-UC phosphors particles of various concentrations in terms of external quantum efficiency and photovoltaic current voltage. Efficiency was shown to increase with an increase in the concentration of NIR-UC phosphors. The efficiency of the cell with a SiO2 layer that included 30 wt% YF3:Yb3+/Er3+ phosphors exceeded the efficiency of a bare solar cell by 13.26%.

In this work, the efficiency of silicon solar cell enhanced by a spectral conversion layer comprising of two-species luminescent down-shifting (LDS) phosphors using spin coating process was demonstrated. Two species of LDS phosphors using co-mixed in silicate solution and single coating, or two species of LDS phosphors separately mixing in silicate solution and double coating, on the silicon solar cells were proposed. The efficiency enhancements of 25.83% (from 11.15% to 14.03%) for the cell with the separate mixing and double coating and 14.0% (from 11.14% to 12.70%) for the cell with co-mixing and one coating were obtained, compared to the reference silicon solar cells.

This paper studied characterized the plasmonic effects of silver nanoparticles (Ag-NPs), the luminescent down-shifting of Eu-doped phosphor particles, and the metal-enhanced fluorescence (MEF) achieved by combining the two processes to enhance the conversion efficiency of silicon solar cells. We obtained measurements of photoluminescence (PL) and external quantum efficiency (EQE) at room temperature to determine whether the fluorescence emissions intensity of Eu-doped phosphor was enhanced or quenched by excitation induced via surface plasmon resonance (SPR). Overall, fluorescence intensity was enhanced when the fluorescence emission band was strongly coupled to the SPR band of Ag-NPs and the two particles were separated by a suitable distance. We observed a 1.125× increase in PL fluorescence intensity at a wavelength of 514 nm and a 7.05% improvement in EQE (from 57.96% to 62.05%) attributable to MEF effects. The combined effects led to a 26.02% increase in conversion efficiency (from 10.23% to 12.89%) in the cell with spacer/NPs/SOG-phosphors and a 22.09% increase (from 10.23% to 12.48%) in the cell with spacer/SOG-phosphors, compared to the bare solar cell. This corresponds to an impressive 0.85% increase in absolute efficiency (from 12.04% to 12.89%), compared to the cell with only spacer/SOG.

In this study, we characterized the performance enhancement of heterojunction silicon solar cells using a luminescent down-shifting phosphor layer of the Eu-doped phosphor at various concentrations (2.5, 5, 7.5 wt%) and at 550 nm emission-wavelength.

We fabricated high speed InAlAs avalanche photodiode without guard ring. It demonstrated the dark current of 1.9 nA and capacitance of 0.16 pF at 0.9 Vbr, and f3-dB of 10 GHz under different incident optical-powers.

In this study, photovoltaic performance enhanced in near-infrared band backward scattering using indium-tin-oxide nanoparticles and up conversion using Yb/Er-doped phosphors particles on the back side of thin silicon solar cells were measured and compared.

DC and AC performance of InAlAs/InGaAs avalanche photodiodes in term of dark-current, capacitance, multiplication-gain and 3-dB frequency (f 3-dB ) were demonstrated. The f 3-dB of 10-18 GHz was achieved using various dimensions of mesa active area.

High-speed mesa-structure avalanche photodiodes with dual-InGaAs absorption-layer and InAlAs multiplication-layer were fabricated and characterized. The 3-dB frequency of 17.7 GHz and gain-bandwidth product of 105 GHz were obtained using a mesa diameter of 30 micrometers.

In this study, by measuring optical reflectance, external quantum efficiency and photovoltaic current-voltage under AM 1.5G solar simulation, the electrical and optical performance of InP/InGaAs solar cells with different thicknesses of ITO antireflective-coating were characterized.

This study reports the use of spectral modulation to solve photocurrent mismatch between sub-cells of triple-junction GaAs solar cell as well as to increase conversion efficiency by using a specific thickness of single antireflection TiO2-layer.

The increased in external quantum efficiency (EQE) and conversion efficiency (η) of silicon solar cells coating multiple up-conversion (UC)-layer on back-side grooved-surface was demonstrated. The EQE- and η-enhancement was 8.4% and 4.7%, due to UC.

In this study, we investigated the electrical and optical performance of single-junction GaAs solar cells coated with an antireflective layer of indium tin oxide (ITO) via thermal sputtering deposition followed by a layer of SiO2 doped with 3 wt% europium-doped (Eu-doped) silicate phosphors via spin-on film technique. The chemical composition of the Eu-doped silicate phosphors was analyzed using energy-dispersive X-ray spectroscopy and the luminescent downshifting (LDS) characteristics were examined in terms of photoluminescence, optical reflectance, and external quantum efficiency (EQE) response. Reverse saturation-current and ideality factor were used to evaluate the passivation performance of ITO films thermal sputtered on GaAs solar cells. The antireflective performance of the ITO film and the LDS effects of the Eu-doped silicate phosphor coatings were respectively evaluated in terms of optical reflectance and EQE response. The enhancement of photovoltaic performance due to LDS effects was confirmed by photovoltaic current density–voltage characteristics of cells under one-sun air mass 1.5G solar simulations. The efficiency enhancement of the cell with only an ITO/SiO2 antireflective layer was 18.39%, whereas the cells coated a SiO2 layer that included various species of Eu-doped phosphors (species-A, species-B, or species-C) on ITO achieved efficiency enhancements of 19.83%, 20.29%, and 21.07%, respectively.

This paper reports on efforts to improve the photovoltaic performance of crystalline silicon solar cells by combining the plasmonic scattering of silver nanoparticles (Ag NPs) with the luminescent downshifting (LDS) effects of Eu-doped phosphors. The surface morphology was examined using a scanning electron microscope in conjunction with ImageJ software. Raman scattering and absorbance measurements were used to examine the surface plasmon resonance of Ag NPs of various dimensions in various dielectric environments. The fluorescence emission of the Eu-doped phosphors was characterized via photoluminescence measurements at room temperature. We examined the combination of plasmonic and LDS effects by measuring the optical reflectance and external quantum efficiency. Improvements in the photovoltaic performance of the solar cells were determined by photovoltaic current density-voltage under AM 1.5G illumination. A combination of plasmonic and LDS effects led to an impressive 26.17% improvement in efficiency, whereas plasmonic effects resulted in a 22.63% improvement compared to the cell with a SiO2 ARC of 17.33%.

This study employed a two-step multi-cycle spin-coating method for the application of MAPbBr3 perovskite nanophosphors on textured silicon solar cells with the aim of enhancing photovoltaic performance through luminescent down-shifting (LDS). The surface morphology and dimensions of the MAPbBr3 perovskite nanophosphors were examined using scanning electron microscopy in conjunction with ImageJ software. The LDS effects of the nanophosphors were revealed by measuring photo-luminance, optical reflectance, and external quantum efficiency. The photovoltaic performance of cells with and without MAPbBr3 perovskite nanophosphors was evaluated according to photovoltaic current density-voltage (J–V) under AM 1.5 G solar illumination. Compared to uncoated cells, two-layer and one-layer coatings of MAPbBr3 perovskite nanophosphors were shown to enhance conversion efficiency by 4.56% and 3.38%, respectively.

In this paper, we experimentally demonstrate the performance of plasmonic silicon (Si) solar cells fabricated using silver (Ag), indium (In), and aluminum (Al) nanoparticles (NPs) of specific dimensions. The nanoparticles were produced using an anodic aluminum oxide (AAO) template as a deposition mask. AAO masks with a thickness of 700 nm and pore diameter of 100–110 nm were fabricated using a single-step anodization and pore widening process aimed at controlling the dimensions and coverage of the metallic NPs with a high degree of precision. Our ultimate objective was to facilitate a comparison of plasmonic effects induced by the various metallic NPs in Si solar cells. Scanning electron microscopy was used to examine the thickness, pore dimensions, and pore size distribution of the AAO template as well as the dimensions and coverage of the deposited metallic NPs. Measurements of optical reflectance and external quantum efficiency were used to characterize the plasmonic effects of the various metallic NPs. Measurements of photovoltaic current density-voltage under AM 1.5G simulation were used to confirm the enhancements in performance resulting from the plasmonic effects induced by the metallic NPs. Ag NPs increased the short-circuit current density (Δ J sc ) of the Si solar cells by 10.58% (from 29.49 to 32.61 mA/cm 2 ), In NPs increased Δ J sc by 7.81% (from 29.31 to 31.60 mA/cm 2 ), and Al NPs increased Δ J sc by 3.27% (from 28.73 to 29.67 mA/cm 2 ). When using metallic nanoparticles (average size of 106 nm and average coverage of 32.67%), the plasmonic effects in cells with Ag NPs exceeded the effects observed in cells fabricated using In-NPs or Al-NPs.

This paper experimentally demonstrates the benefits of combining an up-conversion (UC) layer containing Yb/Er-doped yttrium oxide-based phosphors with a plasmonic scattering layer containing indium nanoparticles (In-NPs) in enhancing the photovoltaic performance of textured silicon solar cells. The optical emissions of the Yb/Er-doped phosphors were characterized using photoluminescence measurements obtained at room temperature. Optical microscope images and photo current-voltage curves were used to characterize the UC emissions of Yb/Er-doped phosphors under illumination from a laser diode with a wavelength of 1550 nm. The plasmonic effects of In NPs were assessed in terms of absorbance and Raman scattering. The performance of the textured solar cells was evaluated in terms of optical reflectance, external quantum efficiency, and photovoltaic performance. The analysis was performed on cells with and without a UC layer containing Yb/Er-doped yttrium oxide-based phosphors of various concentrations. The analysis was also performed on cells with a UC layer in conjunction with a plasmonic scattering layer. The absolute conversion efficiency of the textured silicon solar cell with a combination of up-conversion and plasmonic-scattering layers (15.43%) exceeded that of the cell with an up-conversion layer only (14.94%) and that of the reference cell (14.45%).

In this study, we examined efforts to increase the photovoltaic performance of GaAs single-junction solar cells using spectral conversion layers, respectively, composed of europium-doped (Eu-doped) phosphors, ytterbium/erbium-doped (Yb/Er-doped) phosphors, and a combination of Eu-doped and Yb/Er-doped phosphors. Spin-on film deposition was used to apply the conversion layers, all of which had a total phosphor concentration of 3 wt%. The chemical compositions of the phosphors were examined by energy-dispersive X-ray spectroscopy. The fluorescence emissions of the phosphors were confirmed by using photoluminescence measurements. Under laser diode excitation at 405 nm, we observed green luminescent downshift (LDS) emissions by Eu-doped phosphors at wavelengths of 479 nm to 557 nm, and under excitation at 980 nm, we observed red up-conversion (UC) emissions by Yb/Er-doped phosphors at wavelengths of 647 nm to 672 nm. The spectral conversion layers were characterized in terms of optical reflectance, external quantum efficiency, and photovoltaic current and voltage under AM 1.5 G simulations. The conversion efficiency of the cell combining Eu-doped and Yb/Er-doped phosphors (23.84%) exceeded that of the cell coated with Yb/Er-doped phosphors (23.72%), the cell coated with Eu-doped phosphors (23.19%), and the cell coated without phosphors (22.91%).

This paper presents a novel front-illuminated InAlAs/InGaAs separate absorption, grading, field-control and multiplication (SAGFM) avalanche photodiodes (APDs) with a mesa-structure for high speed response. The electric fields in the InAlAs-multiplication layer and InGaAs-absorption layer enable high multiplication gain and high-speed response thanks to the thickness and concentration of the field-control and multiplication layers. A mesa active region of 45 micrometers was defined using a bromine-based isotropic wet etching solution. The side walls of the mesa were subjected to sulfur treatment before being coated with a thick polyimide layer to reduce current leakage, while lowering capacitance and increasing response speeds. The breakdown voltage (VBR) of the proposed SAGFM APDs was approximately 32 V. Under reverse bias of 0.9 VBR at room temperature, the proposed device achieved dark current of 31.4 nA, capacitance of 0.19 pF and multiplication gain of 9.8. The 3-dB frequency response was 8.97 GHz and the gain-bandwidth product was 88 GHz. A rise time of 42.0 ps was derived from eye-diagrams at 0.9 VBR. There was notable absence of intersymbol-interference and the signals remained error-free at data-rates of up to 12.5 Gbps.

In this study, we sought to enhance the photovoltaic performance of silicon solar cells by coating them (via the spin-on film technique) with a layer of SiO2 containing plasmonic indium-tin-oxide nanoparticles (ITO-NPs) of various concentrations. We demonstrated that the surface plasmon resonance absorption, surface morphology, and transmittance of the ITO-NPs dispersed in SiO2 layer at various concentrations (1&ndash, 7 wt%). We also assessed the plasmonic scattering effects of ITO-NPs within a layer of SiO2 with and without a sub-layer of ITO in terms of optical reflectance, external quantum efficiency, and photovoltaic current-voltage under air mass (AM) 1.5G solar simulation. Compared to an uncoated reference silicon solar cell, applying a layer of SiO2 containing 3 wt% ITO-NPs improved efficiency by 17.90%, whereas applying the same layer over a sub-layer of ITO improved efficiency by 33.27%, due to the combined effects of anti-reflection and plasmonic scattering.

This study experimentally demonstrated enhanced fluorescence emissions from luminescent down-shifting (LDS) Eu-doped phosphors under the effects of localized surface plasmon resonance (LPSR) from silver nanoparticles (Ag NPs). The plasmonic effects of the Ag NPs was examined in terms of plasmon-enhanced Raman scattering and plasmonic absorption. The fluorescence emission of the Eu-doped phosphors was examined in terms of photoluminescence (PL). Overlap between the plasmonic absorption band of Ag NPs and the PL emission band of Eu-doped phosphors increased fluorescence emissions by enhancing excitation. This study also developed an optical process model describing LSPR (Ag NPs), LDS (Eu-doped phosphors), and plasmon-enhanced fluorescence (PEF; Eu-doped phosphors with Ag NPs) on silicon solar cells. PEF was experimentally confirmed in terms of PL, external quantum efficiency (EQE), and photovoltaic current–voltage measurements. Compared to the cell with only an anti-reflection layer of SiO2/SOG, the inclusion of Ag NPs with the Eu-doped phosphors enhanced the PL emission intensity by 1.1243 times at a wavelength of 514 nm and also improved the EQE response by 8.3% (from 57.28% to 62.05%) and conversion efficiency by 7.1% (from 12.04% to 12.89%).

This study experimentally examined the plasmonic near-field and far-field effects of two-dimensional (2-D) indium-nanoparticles (In-NPs) embedded within an anti-reflective SiO2 layer on the optical and electrical characteristics of silicon solar cells. The dimensions and profiles of the 2-D In-NPs were derived from scanning electron microscope images (top-view and side-view) using Image-J software. The surface plasmon resonance of the 2-D In-NPs was estimated from Raman scattering and absorbance measurements. Measurements of optical reflectance and external quantum efficiency revealed that near-field and far-field plasmonic effects depended on the thickness of the spacer and capping layers. The influence of these phenomena on photovoltaic performance was confirmed in terms of photovoltaic current density-voltage under AM 1.5 G illumination. The application of a 90-nm thick SiO2 anti-reflective layer was shown to enhance conversion efficiency by 23.85% (compared to the bare reference cell), and the inclusion of In-NPs between an 18-nm thick spacer layer and 72-nm thick capping layer extended this improvement to 34.16%.

In this study, we sought to enhance the output power and conversion efficiency of textured silicon solar cells by layering two-dimensional indium nanoparticles (In NPs) within a double-layer (SiNx/SiO2) antireflective coating (ARC) to induce plasmonic forward scattering. The plasmonic effects were characterized using Raman scattering, absorbance spectra, optical reflectance, and external quantum efficiency. We compared the optical and electrical performance of cells with and without single layers and double layers of In NPs. The conversion efficiency of the cell with a double layer of In NPs (16.97%) was higher than that of the cell with a single layer of In NPs (16.61%) and greatly exceeded that of the cell without In NPs (16.16%). We also conducted a comprehensive study on the light-trapping performance of the textured silicon solar cells with and without layers of In NPs within the double layer of ARC at angles from 0&deg, to 75&deg, The total electrical output power of cells under air mass (AM) 1.5 G illumination was calculated. The application of a double layer of In NPs enabled an impressive 53.42% improvement in electrical output power (compared to the cell without NPs) thanks to the effects of plasmonic forward scattering.

This paper presents a high-speed top-illuminated InP-based avalanche photodetector (APD) fabricated on conductive InP-wafer using planar processes. The proposed device was then evaluated in terms of DC and dynamic performance characteristics. The design is based on a separate absorption, grading, charge, and multiplication (SAGCM) epitaxial-structure. An electric field-profile of the SAGCM layers was derived from the epitaxial structure. The punch-through voltage of the SAGCM APD was controlled to within 16&ndash, 17 V, whereas the breakdown voltage (VBR) was controlled to within 28&ndash, 29 V. We obtained dark current of 2.99 nA, capacitance of 0.226 pF, and multiplication gain of 12, when the APD was biased at 0.9 VBR at room temperature. The frequency-response was characterized by comparing the calculated 3-dB cut-off modulation-frequency (f3-dB) and f3-dB values measured under various multiplication gains and modulated incident powers. The time-response of the APD was evaluated by deriving eye-diagrams at 0.9 VBR using pseudorandom non-return to zero codes with a length of 231-1 at 10&ndash, 12.5 Gbps. There was a notable absence of intersymbol-interference, and the signals remained error-free at data-rates of up to 12.5 Gbps. The correlation between the rise-time and modulated-bandwidth demonstrate the suitability of the proposed SAGCM-APD chip for applications involving an optical-receiver at data-rates of &gt, 10 Gbps.

In this study, photovoltaic performance enhancements of single-junction GaAs solar Cells using a spectral conversion layer comprising of various species of luminescent down-shifting (LDS) and up conversion (UC) phosphors deposition by spin-on film method are characterized. The peak luminescent wavelength of proposed species of LDS and UC phosphors was 512 nm and 675 nm, respectively. Optical reflectance and external quantum efficiency responses are used to examine LDS and UC effects on the cells. The photovoltaic performance enhancements are confirmed by photovoltaic current density-voltage measurements under AM 1.5G solar simulation. An impressive efficiency of 23.83% of the cell coated with a spectral conversion layer comprising of both species of LDS and up UC phosphors, which exceeding that 23.72% of cell with species of UC, 23.20% of cell with species of LDS and 19.36 of cell without a spectral conversion layer.

In this work, a planar-type top-illuminated high-responsivity InP-based avalanche photodetector (APD) was fabricated and characterized. The dark current of 0.55 nA, capacitance of 0.237 pF, responsivity of 12.2 A/W were obtained when APD operated at 0.95 breakdown voltage (Vbr). The eye diagrams of the fabricated APD under 0.95 VBR to the pseudorandom NRZ code of length 231-1 at 2.5–10 Gb/s were measured. The absence of significant intersymbol interference and the error free for the signals up to 10 Gb/s can be achieved.

This study demonstrates high-efficiency (23.72%) single-junction GaAs solar cell coated with species of NIR up-conversion phosphors layer on the front-side surface by spin-on-film deposition, compared to 19.36% efficiency of the reference single-junction GaAs solar cell.

Plasmonic effects of silver nanoparticles (Ag NPs) of various dimensions embedded and non-embedded in silicon dioxide antireflective coating (SiO2 ARC) deposited by electron-beam evaporation on silicon (Si) solar cells are characterized. Raman scattering and absorbance measurements were used to examine plasmonic resonance absorption of Ag NPs with various particle dimensions and different dielectric environments. The obtained Raman and absorbance results revealed that the large dimensions of Ag NPs exhibited much impressive plasmonic resonance absorption. Furthermore, optical reflectance and photovoltaic current–voltage measurements were also used to confirm the photovoltaic performance enhancement inducing by plasmonic forward scattering of Ag NPs of various dimensions. Thus, the efficiency enhancement of 3.64, 7.42, and 10.24% for the solar cells with Ag NPs in diameter of 21, 25, 32 nm, respectively, embedded in SiO2 ARC was achieved due to plasmonic scattering inducing by Ag NPs, compared to the cell with a pure SiO2 ARC without Ag NPs.

This paper demonstrates the application of a broadband luminescent downshifting (LDS) layer with multiple species of europium (Eu)-doped silicate phosphors using spin-on film technique to enhance the photovoltaic efficiency of crystalline silicon solar cells. The surface morphology of the deposited layer was examined using a scanning electron microscope (SEM). The chemical composition of the Eu-doped silicate phosphors was analyzed using energy-dispersive X-ray spectroscopy (EDS). The fluorescence emission of the Eu-doped silicate phosphors was characterized using photoluminescence (PL) measurements at room temperature. We also compared the optical reflectance and external quantum efficiency (EQE) response of cells with combinations of various Eu-doped phosphors species. The cell coated with two species of Eu-doped phosphors achieved a conversion efficiency enhancement (∆η) of 19.39%, far exceeding the ∆η = 15.08% of the cell with one species of Eu-doped phosphors and the ∆η = 8.51% of the reference cell with the same silicate layer without Eu-doped phosphors.

The additional enhanced in conversion efficiency of the heterojunction with intrinsic thin-layer (HIT) silicon solar cell by using plasmonics scattering of indium nanoparticles (In NPs) was experimentally demonstrated. The conversion efficiency of 17.15% for the HIT solar cell with In NPs was obtained, compared to that of 16.63% for HIT solar cell without In NPs.

Integration of ITO/TiO2/Silicon (metal-oxide-semiconductor; MOS) structure silicon (Si) solar cell and a biasing source of p-n Si solar cells on silicon on insulator wafer was demonstrated. The photovoltaic performances of MOS-structure depended on the biasing voltage are measured and compared. Impressive enhanced in conversion efficiency of 10.63% was obtained when the MOS-structure solar cell was biased a photovoltaic voltage of 2.1V.

This study characterized the electrical and optical properties of single-junction GaAs solar cells coated with antireflective layers of silicon dioxide (SiO2), indium tin oxide (ITO), and a hybrid layer of SiO2/ITO applied using Radio frequency (RF) sputtering. The conductivity and transparency of the ITO film were characterized prior to application on GaAs cells. Reverse saturation-current and ideality factor were used to evaluate the passivation performance of the various coatings on GaAs solar cells. Optical reflectance and external quantum efficiency response were used to evaluate the antireflective performance of the coatings. Photovoltaic current-voltage measurements were used to confirm the efficiency enhancement obtained by the presence of the anti-reflective coatings. The conversion efficiency of the GaAs cells with an ITO antireflective coating (23.52%) exceeded that of cells with a SiO2 antireflective coating (21.92%). Due to lower series resistance and higher short-circuit current-density, the carrier collection of the GaAs cell with ITO coating exceeded that of the cell with a SiO2/ITO coating.

The combination of plasmonic scattering of silver nanoparticles (Ag-NPs) embedded in SiO2 layer and luminescent downshifting (LDS) of Eu-doped phosphor layer applied on silicon solar cells to enhance photovoltaic performances was demonstrated. By annealing 3, 5, and 7 nm thick silver films at 200 °C for 30 min under ambient H2 to form Ag NPs of various dimensions were obtained, which corresponding to the average dimensions of Ag-NPs are 20.13, 25.03, and 32.14 nm determining by SEM images. The optical and electrical properties of the cells with Ag-NPs embedded in a SiO2 antireflection coating (ARC) were characterized firstly by optical reflectance, absorbance, and external quantum efficiency (EQE) measurements. Larger Ag-NPs dimension of 32.14 nm exhibited a larger short-circuit current-density (Jsc) enhancement of 31.24%, which is higher than that of 30.90% for Ag-NPs dimension of 25.03 nm and 28.64% for Ag-NPs dimension of 20.13 nm. The combined effects of plasmonic scattering and LDS are studied by applying Ag-NPs and Eu-doped phosphor particles within SiO2 ARC, which the Jsc enhancement can be further enhanced from 28.64% to 29.37%.

The plasmonic scattering performances of periodic silver nanoparticles (Ag-NPs) deposited on silicon solar cells using anodic aluminum oxide (AAO) mask and e-beam evaporation are demonstrated. The dimension and profile of Ag-NPs are controlled by the pore diameter and configuration of AAO template. Optical reflectance, absorption, external quantum efficiency (EQE), and photovoltaic current-voltage measurements are used to reveal the contribution of plasmonic scattering induced by Ag-NPs of various dimensions. Larger dimension of Ag-NPs exhibited a high efficiency enhancement (from 10.85% to 12.50%) than that of smaller one (10.85% to 12.07%) because the improving in optical reflectance and EQE due to plasmonic scattering of NPs are appeared much high for the cell with large Ag-NPs beyond 650 nm wavelength.

In this study, we demonstrate the photovoltaic performance enhancement of silicon solar cell by means of plasmonics indium nanoparticles (In-NPs) layer embedded in SiO 2 antireflective coating (ARC). The optical reflectance, external quantum efficiency, and photovoltaic current-voltage are measured and compared. Impressive conversion efficiency enhancement of 35.94% for the cell with double In-NPs layers ARC, 34.77% for the cell with single In-NPs layer ARC, and 26.67% for the cell with a pure Si O2 ARC were obtained which is compared to the reference cells. Besides, the gain in absolute efficiency of 1.26-1.52% for the cells with In-NPs ARC was higher than that of the cell with a pure SiO 2 ARC, due to the contribution of plasmonics scattering of In-NPs.

The thermally deposited indium-tin-oxide (ITO) film on single-junction GaAs solar-cell as an excellent antireflection, passivation and window layer to achieve higher efficiency is demonstrated. The passivated characteristic of the ITO-film on GaAs solar-cell is examined by saturation-current and ideality factor. The antireflection of the ITO-film on GaAs solar-cell is revealed by optical-reflectance and external quantum-efficiency. The efficiency of 23.52% for the GaAs cell with ITO antireflection-coating (ARC) was higher than that of 21.92% for the GaAs cell with SiO 2 ARC.

In this study, light trapping of textured silicon solar cell based on light scattering and angle of incident light of plasmonics indium nanoparticles (In NPs) of various dimensions is demonstrated. The light trapping modes of textured surface with and without In NPs for incident angles of 0°, 35.3°, and 54.7° are proposed and characterized. The optical reflectance, external quantum efficiency and photovoltaic performance depended on the dimensions of plasmonics In NPs and angles of incident light are measured and compared.

This study presents high-efficiency of 23.52% single-junction GaAs solar cell using ITO-film as antireflection and passivation layer deposited by thermally-RF-sputtering. The impressive enhanced in efficiency of 8.94% was obtained, compared to the cell with SiO 2 -film.

GaAs-based multi-junction solar cells (MJ-SCs) provide a wide solar-energy absorption-band (300–1800 nm), but designing and fabricating a broadband antireflection coating (ARC) are challenging. Because MJ-SCs are typically in a series that connects each subcell, the total output current is limited by the subcell that generates the smallest photocurrent. Thus, the ARC for MJ-SCs must be designed not only to obtain broadband absorption but also to minimize light reflection at the wavelength band of the current-limited cell. This study proposes a broadband SiO 2 /graded-index TiO 2 ARC for improving the current-limited subcell performance by using a hybrid deposition (e-beam evaporation and spin-on coating). A bottom TiO 2 layer and a top SiO 2 layer were deposited through e-beam evaporation, but the middle TiO 2 layer was deposited using spin-on coating because the refractive index values of the TiO 2 films could be tuned by applying the spin speed. Therefore, the graded-index TiO 2 layers were easily obtained using a hybrid deposition method. In addition, a suitable reflectance spectrum of an ARC structure for a middle-cell current-limited triple-junction (3-J) GaAs solar cell was simulated using commercial optical software. The photovoltaic current–voltage and external quantum efficiency (EQE) were measured and compared. The resulting improvements of a short-circuit current of 32.4% and conversion efficiency of 31.8% were attributed to an enhanced EQE of 32.97% as well as a low broadband reflectance exhibited on the middle cell of the 3-J GaAs solar cell with a SiO 2 /graded-index TiO 2 ARC.

In this paper, we propose and demonstrate a novel technique on improving the conversion efficiency for a metal-insulator-semiconductor (MIS) transistor-based solar cell by using a voltage biasing transparent electrode. The device structure is consisted of a Si-solar cell, a SiO 2 oxide layer, an indium tin oxide (ITO) transparent electrode, and two ohmic-contact electrodes for n-Si and p-Si. The used ITO transparent electrode with a high transmittance at the visible wavelengths and a low sheet resistance are obtained by a sputtering system. The performances of the bare Si-solar cell, the cell with ITO/SiO 2 layers, and the cell with ITO/SiO 2 layers and ITO electrode applying a bias voltage are sequentially characterized under AM1.5 solar illumination. Comparing the performance with the bare solar cell, the efficiency of the solar cell with ITO/SiO 2 films was enhanced of 34.3%. In which, the thin ITO/SiO 2 films provide a function like an anti-reflection (AR) coating. Furthermore, the efficiency as a function of bias-voltage was also observed when the ITO transparent electrode was biased at different volts. At 5 V biasing, the efficiency increasing of more 25.7% was obtained in our recently results, which compared the cell with zero volt biasing. The operation mechanism of the biasing dependent is also discussed.

This study examines using sub-wavelength surface structure (SWS) anti-reflection (AR) coating with a broad wavelength range of low reflectance and wide-acceptance angles of incident light fabricated on solar cells for improving solar cell performance. The SWS AR coating consisted of TiO 2 and SiO 2 layers that had thicknesses of a quarter-wavelength and heights of 300-nm SiO 2 nano-pillars on the top surface of the sub-wavelength structure. The sub-wavelength SiO 2 nano-pillars were formed using a reactive ion etching process with CF 4 that involved using silver nanoparticles as the etching masks. The reflective spectrum of the SWS AR coating was examined using software simulation and experimental measurement. The average reduced reflectance of SWS AR coating was less than 3% between 450 nm and 900 nm wavelengths. SWS AR coating improved solar cell performance in conversion efficiency and maximal output power (P MAX ) at higher incident angle illumination. Therefore, at an incident angle of 60°, the conversion efficiency improvement was 52.9% and the P MAX was 55.8%, as compared with the cells that had two layers (TiO 2 /SiO 2 ) of AR coating.

In this study, we sought to improve the light trapping of textured silicon solar cells using the plasmonic light scattering of indium nanoparticles (In NPs) of various dimensions. The light trapping modes of textured-silicon surfaces with and without In NPs were investigated at an angle of incidence (AOI) ranging from 0° to 75°. The optical reflectance, external quantum efficiency (EQE), and photovoltaic performance were first characterized under an AOI of 0°. We then compared the EQE and photovoltaic current density-voltage (J-V) as a function of AOI in textured silicon solar cells with and without In NPs. We observed a reduction in optical reflectance and an increase in EQE when the cells textured with pyramidal structures were coated with In NPs. We also observed an impressive increase in the average weighted external quantum efficiency (∆EQEw) and short-circuit current-density (∆Jsc) in cells with In NPs when illuminated under a higher AOI. The ∆EQEw values of cells with In NPs were 0.37% higher than those without In NPs under an AOI of 0°, and 3.48% higher under an AOI of 75°. The ∆Jsc values of cells with In NPs were 0.50% higher than those without In NPs under an AOI of 0°, and 4.57% higher under an AOI of 75°. The application of In NPs clearly improved the light trapping effects. This can be attributed to the effects of plasmonic light-scattering over the entire wavelength range as well as an expanded angle of incident light.

The current matching of the middle-cell current-limited triple-junction GaAs/Ge solar-cells after-epitaxial-growth was improved using the matrix-profile TiO2 layer and indium-nanoparticles plasmonics. The optical reflectance, short-circuit current, conversion efficiency and external quantum efficiency are used to characterize the effects of the matrix-profile TiO2 layer and indium-nanoparticles plasmonics on the performances of solar cells. The cell with indium-nanoparticles deposited on the combined layers of a 10-nm-thick TiO2 and a 30-nm-thick TiO2 of 60% coverage shown the improving of current matching in middle-cell that increasing in conversion efficiency by 8.36% and short-circuit current of 12.91% are obtained, compared to the bare solar cells.

We demonstrate the enhanced performances of Si-solar-cells using the spin-on-film device-processes and Indium-nanoparticle plasmonics. The short-circuit-current of the cell with indium-nanoparticles-plasmonics increase by 56.03% (from 3.48 to 5.43 mA) is obtained, compared to the bare-solar-cell.

This paper demonstrate experimentally the top-cell external quantum efficiency (EQE) improving of the triple-junction GaAs-based solar cell using a SiO2-nanopillars/SiO2/TiO2 graded-index anti-reflection coating (GI-ARC). The reflectance and EQE of the solar cells with SiO2/TiO2 double-layer ARC and with SiO2-nanopillars/SiO2/TiO2 GI-ARC are measured and compared. The reflectance of cell with SiO2-nanopillar/SiO2/TiO2 GI-ARC had most favorable low reflectance between 550-700 nm wavelengths. Therefore, the EQE enhancement of 5.88% on top-cell and -1.56% on middle-cell and the best current matching were achieved.

We demonstrate experimentally the improvement of the external quantum efficiency (EQE) and current-matching of the triple-junction GaAs-based solar cell using periodic-patterns incorporated with random nano-sized indium-nanoparticles plasmonics. The average EQE decreased of -9.8% in top-cell and increased of +2.4% in middle-cell were obtained as the solar cell with periodic-patterns random nano-size indium-nanoparticles. Thus, photocurrent generated in the current-limited middle-cell was improved of ~3.4% and the conversion-efficiency was enhanced of ~3.0%, which current matching was also achieved under 1-sun AM1.5G illumination.