Si Solar Cells Research Articles

Decreasing Carrier Mobility under Concentrated Illumination and Its Effect on the Series Resistance and Conversion Efficiency of Silicon Concentrator Solar Cells

The carrier mobility of solar cell materials is a critical physical parameter that determines the series resistance. Furthermore, series resistance is an essential factor affecting the conversion efficiency of concentrator solar cells under high sunlight illumination. However, there has been slight discussion regarding the relationship between these factors. In the previous study, it was reported that concentrated illumination decreased carrier mobility; however, the scattering mechanism has not yet been clarified. Moreover, carrier–carrier scattering was discussed; however, it did not cause a mobility reduction. Thus effective mass changes are discussed as a possible cause of the decrease in carrier mobility under concentrated illumination. The cause of the decrease in mobility under concentrated sunlight illumination cannot be fully elucidated; however, it is a change in lattice scattering. Furthermore, the effect of the decrease in mobility due to concentrated illumination on the series resistance and conversion efficiency of Si solar cells using numerical calculations is clarified. The increase in the series resistance caused by the mobility reduction is ≈10% under 30 suns.

Structural, electronic, and optical-absorption properties of 2D Si thin films

AbstractRecent experimental studies highlighted the potential of thin-film crystalline silicon (Si) for high-efficiency solar cells. Using density functional theory, we investigated 2D Si thin films across various orientations, thicknesses, and surface structures to elucidate their structure–property relationships. Through surface-energy calculations and Wulff construction, we determined the crystal habit of Si, which aligns with available experimental observations. Electronic-structure calculations underscored the critical role of valence saturation on surfaces in enabling semiconducting behavior in Si thin films, essential for optical applications. From optical-absorption calculations, we identified the surface index exhibiting the highest absorption coefficients for thin films Si solar cell applications. Graphical abstract

Determination of critical energy release rate at the EVA/Si cell interface of a flexible silicon solar cell

Recently, commercial flexible silicon(Si) solar cells have been available for charging batteries and electronic devices. In this research, we present a methodology for determining the critical energy release rate at the EVA/Si cell interface of a flexible silicon solar cell, which can also be applied to other interfaces in solar cells. The outline of procedure is as follows:•Conduct a peeling test at the EVA/Si cell interface of the solar cell sample•Perform a tensile test on the upper layer of the solar cell sample•Execute IC Peel softwareInputs: Peeling force between EVA and Si layer, Young's modulus (E), Yield stress (σy), and Yield strain (εy) of the upper layerOutput: critical energy release rate (Gc) between EVA and the silicon (Si) layer

Exploring low temperature-sputtered indium tin oxide (ITO) as an anti-reflection layer for silicon solar cells

Abstract This paper tackles challenges in silicon (Si) solar cells, specifically the use of hazardous Phosphorus Oxychloride (POCl3) for emitter formation and silane/ammonia for the Anti-Reflective Coating (ARC) layer, accompanied by high-temperature metallization. The study proposes an eco-friendly ARC layer process, replacing toxic materials. Indium Tin Oxide (ITO) with a refractive index of ∼2.0 is suggested as a non-toxic substitute for SiN x in the ARC layer. ITO enables fine-tuning of optical parameters and, with its electrical properties, supports low-resistivity contacts through efficient, low-temperature metallization processes. ITO-passivated solar cells with Ag polymer paste as a front contact exhibit promising characteristics: a commendable photocurrent density (J sc) of 20 mA cm−2 at 850 °C, low series resistance (R s) of 1.9 Ω, and high shunt resistance (R shunt) of 28.9 Ω, as demonstrated by illuminated I–V measurements. Implementing ITO as the ARC on a less toxic emitter junction enhances Si solar cells’ current density gain, minimizing current leakage during high-temperature processing. In conclusion, adopting less toxic materials and employing low-temperature processing in passive silicon solar cell fabrication presents an attractive alternative for cost reduction and contributes to environmentally sustainable practices in green manufacturing.

Translucent Si Solar Cells Patterned with Pulsed Ultraviolet Laser Beam

We report an application of a pulsed ultraviolet (UV) laser (λ = 355 nm) in producing translucent Si solar cells. This process efficiently generates a densely packed microhole array on a fully fabricated Si P‐N junction solar cell in just a few minutes. Herein, prototype cells with a nominal microhole diameter of 23 μm with a spacing between 60 and 300 μm are fabricated. High‐resolution electron‐beam microscopy reveals that the UV laser beam introduces amorphized silicon oxide (SiOx) in proximity to the patterned microholes via localized heating in air. Quantitative photovoltaic (PV) analysis shows a decline in the open‐circuit voltage (Voc) and the fill factor (FF) of the cells with the increase in the microhole density, likely due to the P‐N junction damage during the laser beam irradiation. Despite the reduction in Voc and FF, the solar cells retain a short‐circuit current density (Jsc) above 90% without post‐processing. The inherent microhole geometry associated with the laser beam profile allows multiple light scattering within the confined microhole structure, enhancing the translucency of the cells. While further development is required for optimization, these findings support the potential use of UV laser beams for fast and scalable production of translucent solar cells.

Visible/near-infrared luminescence and concentration effects of Pr3+-doped Sr2Al2GeO7 downconversion phosphors

The Pr3+ ion has been widely doped into various materials as a red and near-infrared (NIR) emitting center for applications in lighting and solar spectrum downconversion. Herein, the preparation of a new library of Pr3+-doped Sr2Al2GeO7 phosphors was proved by powder x-ray diffraction patterns and Rietveld refinements and characterized by a scanning electron microscope with energy-dispersive x-ray spectrometry. The Sr2Al2GeO7:Pr3+ sample strongly absorbs blue photons over 420–500 nm and yields intense visible emissions with dominant peaks around 490 nm from the Pr3+ 3P0 → 3H4 transition, as well as robust NIR emission bands over 800–1200 nm. In addition to the typical transitions of 1D2 → 3F2 at 880 nm, 1G4 → 3H4 at 1000 nm, and 1D2 → 3F3,4 at 1070 nm, the distinguishable NIR emission at 929 nm was demonstrated from the 3P0 → 1G4 transition via static and dynamic spectroscopic analysis. Most interestingly, for the 3P0 blue-excited state, a considerably elevated concentration of about 10%Pr3+ was optimal for the visible/NIR emissions, in stark contrast to the diluted optimal 1%Pr3+ for the 1D2 state. The relevant cross-relaxation from the 3P0 and 1D2 states between Pr3+ was comprehensively treated by theoretical speculations and experimental results. Such concentrated Pr3+ blue activators would significantly facilitate the blue-to-NIR downconversion through a desired two-step sequential transition from the 3P0 initial state to the 1G4 intermediate level for quantum efficiency exceeding unity. The current results would consolidate the basis of concentrated Pr3+ donors to promote the novel Pr3+/Yb3+ codoping downconversion for greatly increasing Si solar cell efficiency.

Doubling Power Conversion Efficiency of Si Solar Cells.

Improving solar cells' power conversion efficiency (PCE) is crucial to further the deployment of renewable electricity. In addition, solar cells cannot function at exceedingly low temperatures owing to the carrier freeze-out phenomenon. This report demonstrates that through temperature regulation, the PCE of monocrystalline single-junction silicon solar cells can be doubled to 50-60% under monochromatic lasers and the full spectrum of AM 1.5 light at low temperatures of 30-50 K by inhibiting the lattice atoms' thermal oscillations for suppressing thermal loss, an inherent feature of monocrystalline Si cells. Moreover, the light penetration, determined by its wavelength, plays a critical role in alleviating the carrier freeze-out effect and broadening the operational temperature range of silicon cells to temperatures as low as 10 K. Understanding these new observations opens tremendous opportunities for designing solar cells with even higher PCE to provide efficient and powerful energy sources for cryogenic devices and outer and deep space explorations.

Enhancing solar cell productivity with MgAl2O4–ZnAl2O4 blended anti-reflection coatings

The enhancement of productivity in solar cells primarily relies on the application of anti-reflection coatings. The current research employs coating materials such as MgAl2O4, ZnAl2O4 and blended MgAl2O4–ZnAl2O4 as an anti-reflective layer on the monocrystalline Si solar cells by employing RF sputter coating method. Magnesium nitrate hexahydrate and aluminium nitrate nonahydrate were utilized for the synthesis of MgAl2O4 by the sol-gel technique. ZnAl2O4 was synthesized using zinc nitrate hexahydrate and aluminum nitrate nonahydrate by sol–gel procedure. The performance of coated photovoltaic cells was evaluated through different characterization techniques. From the optical study, the blended MgAl2O4-ZnAl2O4 coating shows the maximum absorbance of around 93 % and lowest reflectance of 9 %. The MgAl2O4–ZnAl2O4 blend achieves a maximum power conversion efficiency (PCE) of 22.12 % in a controlled light source and 19.21 % in direct sunlight. Compared to other solar cells, blended MgAl2O4–ZnAl2O4 demonstrates low resistivity (4.23 × 10−3 Ω-cm), high carrier concentration (35.81 × 1020 cm−3) and maximum hall mobility (12.96 cm2/Vs). From the surface temperature measurement, it is evident that the MgAl2O4–ZnAl2O4 blend coated solar cell exhibits lowest temperature of 38.2 °C under simulated light. The experimental results indicate that the blended MgAl2O4–ZnAl2O4 coated photovoltaic cells exhibits superior productivity than the various coated and uncoated solar cells. Therefore, it can be stated that MgAl2O4–ZnAl2O4 blends are the excellent antireflective materials for achieving desired PCE in solar photovoltaic cells.

Homogeneously Mixed Cu-Co Bimetallic Catalyst Derived from Hydroxy Double Salt for Industrial-Level High-Rate Nitrate-to-Ammonia Electrosynthesis.

Electrocatalytic nitrate reduction reaction (NO3RR) presents an innovative approach for sustainable NH3 production. However, selective NH3 production is hindered by the multiple intermediates involved in the NO3RR process and the competitive hydrogen evolution reaction. Hence, the development of highly efficient NO3RR catalysts is paramount. Herein, we report highly efficient bimetallic catalysts derived from hydroxy double salt (HDS). Under NO3RR conditions, Cu1Co1-HDS undergoes in situ reconstruction, forming nanocomposites of homogeneously distributed metallic Cu0 and Co(OH)2. Reconstruction-induced Cu0 rapidly converts NO3- to NO2-, which is further hydrogenated to NH3 by Co(OH)2. Homogeneously mixed Cu and Co species maximize this synergistic effect, achieving outstanding NO3RR performance including the highest NH3 yield rate (4.625 mmol h-1 cm-2) reported for powder-type NO3RR catalysts. Integration of Cu1Co1-HDS with a commercial Si solar cell attained 4.53% solar-to-ammonia efficiency from industrial wastewater-level concentrations of NO3- (2000 ppm), demonstrating practical application potential for solar-driven NH3 production. This study provides a strategy for enhancing the NH3 yield rate by optimizing the compositions and distributions of Cu and Co.

P-Doped Carbon Nanotubes As Light Absorbers and Electron Donors in Photovoltaics

Doping is a ubiquitous and powerful tool used to alter a material’s electronic properties. Conventional Si solar cells would not exist without it, and it has been used to increase the efficiency of organic and inorganic photovoltaics alike. While doped carbon nanotubes (CNTs) have been the subject of numerous spectroscopic studies, few investigations have examined their performance in photovoltaic devices. Here, we incorporate chemically p-doped CNTs into photovoltaic heterojunctions with C60. In a conventional CNT–C60 heterojunction device, photocurrent can be produced when photogenerated excitons in the CNT layer diffuse to the CNT–C60 heterointerface. The offset in conduction band energy drives dissociation of these excitons via photoelectron transfer from CNT to C60, which yields separated charges that can be collected. Our objective here was to determine the following: 1) does p-doping increase or decrease the efficiency with which excitons dissociate into electrons and holes? 2) Do p-dopants trap excitons and inhibit their diffusion to the heterointerface? 3) How efficiently can a photogenerated trion (exciton coupled to an injected hole) be dissociated to produce a photocurrent?To answer these questions, we fabricated polymer wrapped (6,5) CNT–C60 heterojunctions over a range of CNT thickness with various levels of p-doping introduced by triethyloxonium hexachloroantimonate treatment. We measured photocurrent to quantify relative photoelectron transfer efficiency for both excitons and trions and compared this to photoluminescence and transient absorbance measurements on doped CNT films. We found that p-doping decreases photocurrent because injected holes bleach the CNTs’ S11 transition and decrease the amount of light absorbed. Meanwhile, the photogenerated exciton to collected electron transfer efficiency remains unchanged for doping densities up to 50μm-1. In contrast, photoluminescence quantum yield drops by over 90% at an equivalent doping density. We attribute this disparity to the fast electron transfer at the CNT–C60 interface, which occurs on the order of femtoseconds. We also found that moderate doping can promote photocurrent at the trion peak, with a photogenerated trion to collected electron transfer efficiency about 1/4 that of the photogenerated exciton to collected electron transfer efficiency. Photocurrent at the trion absorption peak is invariant with reverse bias up to 0.3 V, despite the charged nature of the trion, supporting evidence for the immobile nature of trions. These results indicate that p-CNTs are a viable material for use in photovoltaics, albeit with weaker absorption, and that photocurrent from trions is possible, although with lower quantum efficiency. Figure 1

Green H2 Generation from Seawater Deploying a Bifunctional Hetero-Interfaced CoS2-CoFe-Layered Double Hydroxide in an Electrolyzer.

This work illustrates the practicality and economic benefits of employing a hetero-interfaced electrocatalyst (CoS2@CoFe-LDH), containing cobalt sulphide and iron-cobalt double-layer hydroxide for large-scale hydrogen generation. Here, the rational synthesis and detailed characterization of the CoS2@CoFe-LDH material to unravel its unique heterostructure are essayed. The CoS2@CoFe-LDH operates as a bifunctional electrocatalyst to trigger both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline seawater (pH 14.0) while showcasing low overpotential requirement for HER (311mV) and OER (450mV) at 100mAcm- 2 current density. The identical CoS2@CoFe-LDH on either electrode in an H-cell setup results in simultaneous H2 and O2 production from seawater with a ≈98% Faradaic efficiency with an applied potential of 1.96V@100mAcm- 2. Next, this CoS2@CoFe-LDH catalyst is deployed on both sides of a membrane electrode assembly in a one-stack electrolyzer, which retains the intrinsic bifunctional reactivity of the catalyst to generate H2 and O2 in tandem from alkaline seawater with an impeccable energy efficiency (50kWhkg-1-of-H2). This electrolyzer assembly can be directly linked with a Si-solar cell to produce truly green hydrogen with a solar-to-hydrogen generation efficiency of 15.88%, highlighting the potential of this converting seawater to hydrogen under solar irradiation.

Fabrication of Thermally Evaporated CuIx Thin Films and Their Characteristics for Solar Cell Applications

Carrier-selective contacts (CSCs) for high-efficiency heterojunction solar cells have been widely studied due to their advantages of processing at relatively low temperatures and simple fabrication processes. Transition metal oxide (TMO) (e.g., molybdenum oxide, vanadium oxide, and tungsten oxide) thin films are widely used as hole-selective contacts (HSCs, required work function for Si solar cells > 5.0 eV). However, when TMO thin films are used, difficulties are faced in uniform deposition. In this study, we fabricated a copper (I) iodide (CuI) thin film (work function > 5.0 eV) that remained relatively stable during atmospheric exposure compared with TMO thin films and employed it as an HSC layer in an n-type Si solar cell. To facilitate efficient hole collection, we conducted iodine annealing at temperatures of 100–180 °C to enhance the film’s electrical characteristics (carrier density and carrier mobility). Subsequently, we fabricated CSC Si solar cells using the annealed CuIx layer, which achieved an efficiency of 6.42%.

Light-trapping by wave interference in intermediate-thickness silicon solar cells

The power conversion efficiency of crystalline silicon (c − Si) solar cells have witnessed a 2.1% increase over the last 25 years due to improved carrier transport. Recently, the conversion efficiency of c − Si cell has reached 27.1% but falls well below the Shockley-Queisser limit as well as the statistical ray-optics based 29.43% limit. Further improvement of conversion efficiency requires reconsideration of traditional ray-trapping strategies for sunlight absorption. Wave-interference based light-trapping in photonic crystals (PhC) provides the opportunity to break the ray-optics based 4n 2 limit and offers the possibility of conversion efficiencies beyond 29.43% in c − Si cells. Using finite difference time domain simulations of Maxwell’s equations, we demonstrate photo-current densities above the 4n 2 limit in 50 − 300µm-thick inverted pyramid silicon PhCs, with lattice constant 3.1µm. Our 150µm-thick PhC design yields a maximum achievable photo-current density (MAPD) of 45.22mA/cm 2. We consider anti-reflection coatings and surface passivation consisting of SiO 2 − SiN x − Al 2 O 3 stacks. Our design optimization shows that a 80 − 120 − 150nm stack leads to slightly better solar light trapping in photonic crystal cells with thicknesses <50µm, whereas the 80 − 40 − 20nm stack performs better for cells with thicknesses >100µm. We show that replacing SiN x with SiC may improve the MAPD for PhC cells thinner than 100µm. For a fixed lattice constant of 3.1µm, we find no significant improvement in the solar absorption for 50 and 100µm-thick cells relative to a 15µm cell. A substantial improvement in the MAPD is observed for the 150µm cell, but there is practically no improvement in the solar light absorption beyond 150µm thickness.

Evaluation of the effect of texture size and rounding process on three-dimensional flexibility of c-Si wafer

Vehicles are expected to be a new application field for solar cells. Since vehicle bodies have complicated three-dimensional curved surfaces designed to improve aerodynamic performance, there is a need for flexible solar cells that can be installed on such surfaces. To this end, research has focused on single-crystalline Si solar cells with high conversion efficiency and reliability, since the flexibility of Si wafers improves as they become thinner. Previous studies have reported that the texture structure to improve the light absorption on the Si wafer surface affects the three-dimensional flexibility. In this work, we perform a Ball-on-Ring test to determine how texture size and rounding treatment affect the flexibility of c-Si wafers and measure the flexibility. The results demonstrate that the rounding process increases flexibility, while the texture size reduction improves flexibility.

Deep learning-based prediction of 3-dimensional silver contact shapes enabling improved quality control in solar cell metallization

The industrial metallization of Si solar cells predominantly relies on screen printing, with silver as the preferred electrode material. However, the design of commercial screens often leads to suboptimal silver usage and increased electrical resistance due to print-related inhomogeneities like mesh marks, constrictions and spreading. Real-time monitoring of quality parameters during production has thus become increasingly critical. Current inline optical quality control systems usually only include 2D visualizations of the printed layout, which limits their effectiveness in quality control. Options that allow 3D measurements are usually slow, expensive, and therefore not worth considering in most cases. This research focuses on the development of a model that can estimate the three-dimensional shape of printed contact fingers from a single 2D image without the need of additional hardware using deep learning. Furthermore, a workflow for the generation of training data, which involves the creation of image pairs from a 2D microscope and a 3D confocal laser scanning microscope (CLSM) to accurately represent solar cell fingers, is presented. After model training, the predicted height maps are compared with the ground truth height maps, and the robustness of the model with respect to a paste variation and screen parameter variation is examined. The results confirm the feasibility and reliability of deep learning-based 3D shape estimation, extending its applicability to new, previously unseen data from screen-printed contact fingers. With a structural similarity index (SSIM) score of 0.76, a strong correlation between the estimated and ground truth height maps is established. In summary, our deep learning-based approach for height map estimation offers an effective and reliable solution for fast inline detection and analysis of the cross-sectional area of the printed contact fingers.

CO2-to-CO conversion with over 10% efficiency using earth abundant system in a single-compartment reactor with oxygen tolerant Mn complex catalyst.

The direct conversion of CO2 in flue gas to value-added chemicals is a potentially important cost-effective solar-driven CO2 reduction technology. The present work demonstrates the solar-powered conversion of CO2 to CO with greater than 10% efficiency using a Mn complex cathode and an Fe-Ni anode in a single-compartment reactor without an ion exchange membrane in conjunction with a Si solar cell. Reactors separated by ion exchange membranes are typically used to prevent any effects of oxygen generated by the counter electrode. However, the present Mn complex catalyst maintained its activity even in the presence of 15% O2. Operando surface-enhanced Raman spectroscopy established that the present Mn catalyst preferentially reacted with CO2 without adsorbing O2. This unique characteristic enabled solar-driven CO2 reduction using a single-compartment reactor. In contrast, catalytic metals such as Ag tend to lose activity in such systems as a consequence of reaction with oxygen produced at the anode.

Broadband sensitized near-infrared emission in Eu2+-Nd3+ co-doped BaAl2O4 as a potential spectral modulator for silicon solar cells.

The near-infrared (NIR) down-conversion process for broadband sensitization has been studied in Eu2+-Nd3+ co-doped BaAl2O4. This material has a broad absorption band of 200-480 nm and can convert photons in the visible region into NIR photons. The NIR emission at 1064 nm, attributed to the Nd3+:4F3/2 → 4I11/2 transition, matches the bandgap of Si, allowing Si solar cells to utilize the solar spectrum better. The energy transfer (ET) process between Eu2+ and Nd3+ was demonstrated using photoluminescence spectra and luminescence decay curves, and Eu2+ may transfer energy to Nd3+ through the cooperative energy transfer (CET) to achieve the down-conversion process. The energy transfer efficiency (ETE) and theoretical quantum efficiency (QE) were 68.61% and 156.34%, respectively, when 4mol% Nd3+ was introduced. The results indicate that BaAl2O4:Eu2+-Nd3+ can serve as a potential modulator of the solar spectrum and is expected to be applied to Si solar cells.

Silicon nanohole based enhanced light absorbers for thin film solar cell applications

We proposed a nanohole-based silicon (Si) absorber structure to enhance the light absorption of thin-film Si solar cells. Our proposed structures exhibited excellent performances harnessing the light-matter interaction phenomenon with a few microns of thick Si (3 µm). We employed the finite-difference time-domain method to analyze the optical properties and solved Poisson’s, continuity, and heat transfer equations to analyze the electrical and thermal properties of our proposed structures, operating in the wavelength range from 300 to 1100 nm. We obtained a maximum average absorption of 72.6% for our proposed square hole Si absorber structure. The power conversion efficiency and short circuit current density were calculated to be 20.74% and 39.91 mA/cm2. We achieved polarization-insensitive performance due to the symmetrical nature of the structure. The temperature of our proposed structure was increased by ∼10 K due to light absorption for different ambient temperatures. Moreover, we found our proposed structure was thermally stable over time. Our proposed structures can enhance the absorption of Si nanostructures, which can be conducive to designing Si-thin solar cells for energy harvesting.

Double-diode model carrier lifetime-based internal recombination parameter analysis and efficiency prediction of crystalline Si solar cells

With the continuous and significant advancements in the performance of crystalline silicon (c-Si) solar cells, an effective method for a detailed analysis of the efficiency loss factors is increasingly important. Specifically, a detailed analysis of recombination parameter (J0) is crucial for devising strategies to approach the theoretical efficiency limit. In this study, we propose an analysis method that utilizes minority carrier lifetime based on the double-diode model and predicts the performance efficiency of c-Si solar cells. The analysis, conducted through the p-PERC structure, examines the contributions to J0 from different recombination areas. The advantages of this method include: (i) its relative simplicity and reliance on non-destructive analysis techniques; (ii) its capability to extract internal recombination parameters, such as J0,total emitter, J0,rear, and J02, from a fully assembled solar cell with metal contacts. Furthermore, this method serves as a diagnostic tool to identify the sequence in which parameters should be adjusted to enhance solar cell efficiency effectively and to pinpoint areas within the solar cell that significantly limit performance efficiency. Using this method, the diagnosis of the p-PERC cell revealed that the main cause of performance limitation was the emitter in the front region. The carrier lifetime analysis showed that for overcoming cell performance limitations, it is more effective to design process improvements in the following order: i) front emitter region (J0,em), ii) space charge region (J02), iii) rear surface region (J0r).

Upright Pyramid Surface Textures for Light Trapping and MoOx Layer in Ultrathin Crystalline Silicon Solar Cells

In this work, ray tracing is used to investigate the optical characteristics of various surface structures in ultrathin crystalline silicon (c-Si) for solar cells. Ultrathin c-Si with a thickness of 20 μm is used as the substrate. The light trapping includes front upright pyramids with a molybdenum oxides (MoOx) anti-reflection (AR) layer. Planar ultrathin c-Si (without a MoOx AR layer and upright pyramids) is used as a reference. The wafer ray tracer was developed by a photovoltaic (PV) lighthouse to model the MoOx AR layer to reduce the front surface reflectance and impacts of the AR layer on ultrathin Si solar cells. The optical properties are calculated on the AM1.5 global solar energy spectrum across the 200–1200 nm wavelength region. From the absorbance profile, the photogenerated current density (Jph) in the substrate is also calculated with various surface structures. The front upright pyramids with the MoOx layer result in the largest absorbance enhancement due to the enhanced light scattering by the pyramids and MoOx AR layer. The Jph of 37.41 mA/cm2 is improved when compared to the planar ultrathin c-Si reference. This study is significant as it illustrates the potential of ultrathin c-Si as a promising PV module technology in the future.