Monocrystalline Film Research Articles

Van der Waals Integration of Large-Area Monocrystalline 3D Perovskite Thin Films on Arbitrary Semiconductor Substrates for Heterojunctions.

Perovskite monocrystalline films are regarded as desirable candidates for the integration of high-performance optoelectronics due to their unique photophysical properties. However, the heterogeneous integration of a perovskite monocrystalline film with other semiconductors is fundamentally limited by the lattice mismatch, which hinders direct epitaxy. Herein, the van der Waals (vdW) integration strategy for 3D perovskites is developed, where perovskite monocrystalline films are epitaxially grown on the mother substrate, followed by its peeling off and transferring to arbitrary semiconductors, forming monocrystalline heterojunctions. The as-achieved CsPbBr3-Nb-doped SrTiO3 (Nb:STO) vdW p-n heterojunction exhibited comparable performance to their directly epitaxial counterpart, demonstrating the feasibility of vdW integration for 3D perovskites. Furthermore, the vdW integration could be extended to silicon substrates, rendering the CsPbBr3-n-Si and CsPbCl3-p-Si p-n heterojunction with apparent rectification behaviors and photoresponse. The vdW integration significantly enriches the selections of semiconductors hybridizing with perovskites and provides opportunities for monocrystalline perovskite optoelectronics with complex configurations and multiple functionalities.

Solid-State Anion Exchange Enabled by Pluggable vdW Assembly for In Situ Halide Manipulation in Perovskite Monocrystalline Film.

The fabrication of perovskite single crystal-based optoelectronics with improved performance is largely hindered by limited processing techniques. Particularly, the local halide composition manipulation, which dominates the bandgap and thus the formation of heterostructures and emission of multiple-wavelength light, is realized via prevalent liquid- or gas-phase anion exchange with the utilization of lithography, while the monocrystalline nature is sacrificed due to polycrystalline transition in exchange with massive defects emerging, impeding carrier separation and transportation. Thus, a damage-free and lithography-free solid-state anion exchange strategy, aiming at in situ halide manipulation in perovskite monocrystalline film, is developed. Typically, CsPbCl3 working as medium to deliver halide is van der Waals (vdW) assembled to specific spots of CsPbBr3, followed by the removal of CsPbCl3 after anion exchange, with the halide composition in contact area modulated and monocrystalline nature of CsPbBr3 preserved. CsPbBr3-CsPbBrxCl3-x monocrystalline heterostructure has been achieved without lithography. Device based on the heterostructure shows apparent rectification behavior and improved photo-response rate. Heterostructure arrays can also be constructed with customized medium crystal. Furthermore, the halide composition can be accurately tuned to enable full coverage of visible spectra. The solid-state exchange enriches the toolbox for processing vulnerable perovskite and paves the way for the integration of monocrystalline perovskite optoelectronics.

Evaluation of electrical power losses of photovoltaic modules subjected to partial shading conditions in the three climatic regions of Cameroon

This paper studies the behavior of three types of photovoltaic panels operating under partial shading conditions in the three climatic regions of Cameroon. The phenomenon of partial shading constitutes one of the factors which drastically disrupt the electric power produced by the photovoltaic generators. It is to contribute to solve this problem that we modelled the PV panels operating in partial shading conditions under the climatic parameters of the study area. The analytical method combined with the iterative method are used for the determination of PV module parameters under partial shading conditions. Studies were carried out over a period of one year in three cities, respectively: Yagoua for the sudano-sahelian region, Tchollire in the sudanese region and Tibati in the southern equatorial region. Three types of PV panels were used {polycrystalline (MSX-60), monocrystalline (Shell SP70) and CIS thin film (Shell ST40)}. The electrical power losses of each type of panel were evaluated.

Effects of photovoltaic panel type on optimum sizing of an electrical energy storage system using a stochastic optimization approach

This article proposes a stochastic optimization approach for an off-grid solar-wind with an electrical energy storage structure. The proposed optimization approach is a probabilistic algorithm based on simulated annealing for approximating the global optimum of the objective function. The optimal size of the electrical energy storage system for the solar-wind energy system as the final aim is calculated considering the reliability and annualized cost of the system. The objective function of this study is to reduce the unavailability and cost of the system with different types of solar panels (monocrystalline, polycrystalline, and thin film). The optimization process of the system size is accomplished using a stochastic optimization approach by considering the battery capacity, photovoltaic (PV) panel, and wind turbine area as decision variables. The harmony search algorithm is used to confirm the optimality of the system. The effects of photovoltaic panel type on the optimum sizing of electrical energy storage system are calculated in a case study over a year. So, a sensitivity study is performed to analyze the effect of the initial costs of components and the efficiency of photovoltaic panels on the annualized cost of the system. The results show that polycrystalline-PV solar/battery systems are more suitable for the proposed location than other systems, due to economic, technical, and environmental conditions. Also, the stochastic optimization approach is effective for the sizing process and can achieve the goals of the system. In three solar cell types, there is a slight increase (about 3.6 %) in TCOS (total cost of the system) value by increasing PV panel unit cost; and, there is a significant decrease in TCOS value (about 82 %) by decreasing battery unit cost; also, there is a significant decrease in TCOS value (about 28 %) by increasing PV efficiency.

Effects of wind speed and temperature on economics and environmental impact assessment of different solar PV systems in Malaysia

This study aims to analyse the effect of temperature and wind speed on the performance of different types of photovoltaic (PV) systems at a different state in Malaysia and how it affects the economics and environmental impact assessment in the present year of 2018 as well as future years in 2030 and 2040. Three types of grid-connected solar PV modules namely Mono-Crystalline, Poly-crystalline, and Thin Film were selected to be implemented in different cities of Shah Alam, Chuping, Alor Setar, Ipoh and Kota Kinabalu. A mathematical model was adopted to estimate the performance characteristics of the solar PV modules. Based on the data in the present year, the highest power output produced by the Mc-Si module for Alor Setar city is given by 33.40 MWh/year while the lowest amount of power output provided by this PV panel is about 28.18 MWh/year in Shah Alam. Furthermore, an area of 144 m2 for the Mono-Crystalline PV module can satisfy the total energy requirement by the resident as it was the most profitable to be implemented compared to Poly-crystalline and Thin Film. The findings of this study can serve as important information on the economic viability of installing PV systems in the selected cities in Malaysia.

Improving Performance of Al2O3/AlN/GaN MIS HEMTs via In Situ N2 Plasma Annealing.

A novel monocrystalline AlN interfacial layer formation method is proposed to improve the device performance of the fully recessed-gate Al2O3/AlN/GaN Metal-Insulator-Semiconductor High Electron Mobility Transistors (MIS-HEMTs), which is achieved by plasma-enhanced atomic layer deposition (PEALD) and in situ N2 plasma annealing (NPA). Compared with the traditional RTA method, the NPA process not only avoids the device damage caused by high temperatures but also obtains a high-quality AlN monocrystalline film that avoids natural oxidation by in situ growth. As a contrast with the conventional PELAD amorphous AlN, C-V results indicated a significantly lower interface density of states (Dit) in a MIS C-V characterization, which could be attributed to the polarization effect induced by the AlN crystal from the X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM) characterizations. The proposed method could reduce the subthreshold swing, and the Al2O3/AlN/GaN MIS-HEMTs were significantly enhanced with ~38% lower on-resistance at Vg = 10 V. What is more, in situ NPA provides a more stable threshold voltage (Vth) after a long gate stress time, and ΔVth is inhibited by about 40 mV under Vg,stress = 10 V for 1000 s, showing great potential for improving Al2O3/AlN/GaN MIS-HEMT gate reliability.

Deposition of GeSn film on Si substrate by plasma-enhanced chemical vapor deposition using GeCl4 and SnCl4 in H2 for developing short-wave infrared Si photonics

The deposition of a GeSn film on Si substrate with GeCl4 and SnCl4 in H2 as precursors was demonstrated by using plasma-enhanced chemical vapor deposition (PECVD). A partially strain-relaxed, impurity-free, monocrystalline GeSn film with a surface roughness of 6 nm and a threading-dislocation density of 1 × 107 cm−2 could be directly grown at a rate of ca. 15 nm/min at a substrate temperature of 180 °C without the need of a buffer layer or post-annealing. A Sn atomic percentage exceeding 9% was achieved, providing a light absorption beyond 2.4μm for the deposited 260-nm-thick film. The same deposition process for Ge and Sn enabled easier control of film deposition conditions and better clarification of the underlying mechanisms. The low deposition temperature renders this method compatible with complementary metal–oxide–semiconductor (CMOS) technology, suitable for developing short-wave infrared Si photonics.

Techno-economic analysis for optimal configurations of PV systems with back reflectors

With the growth in the solar photovoltaic (PV) market, there is a renewed interest in increasing the system’s annual produced energy. Most of the proposed solutions in the literature require special additional equipment, which might adversely affect the cost of the produced energy. This paper proposes an integrated PV-reflector system that augments the solar irradiance on already installed PV modules. A new mathematical model has been developed in MATLAB R2020a to simulate and techno-economically assess the proposed integrated PV system during the entire year using real meteorological data. A genetic algorithm has been employed in MATLAB R2020a to obtain the optimal geometric and optical parameters that maximize the annual produced energy and minimize the Levelized Cost of Electricity (LCOE) at two selected locations (Cairo in Egypt and Ma’an in Jordan) and for three module technologies (monocrystalline, polycrystalline, and thin film) and different commercial reflectors. The optimal system configurations increased the annual energy production by up to 6.05, 5.14, and 8.34% for the three PV technologies, respectively. For both locations, the optimal tilt angles of the PV module and reflector range between 24° and 34° for Cairo, and between 19° and 36° for Ma’an, depending on the PV technology. Finally, all the system configurations have favorable and low payback periods (∼3 and 6.5 years for Ma’an and Cairo, respectively), as well as attractive LCOE, which varies between 0.0369 and 0.044 USD/kWh in Ma’an and between 0.0543 and 0.065 USD/kWh in Cairo.

Effect of thermal annealing on the structural and optical properties of ZnGa2O4 films deposited on sapphire by magnetron sputtering

ZnGa2O4 films were prepared on α-Al2O3 (0006) wafer at room temperature using magnetron sputtering. The impact of thermal annealing on the crystallization quality, epitaxial relationship and optical property of the films were studied in detail. XRD results showed that the crystalline quality of film was significantly improved by annealing, and the 500 °C-annealed sample presented a monocrystalline film with the best crystallization quality. The results of XRD and HRTEM revealed an epitaxial relationship of ZnGa2O4 (111)//α-Al2O3 (0006) with ZnGa2O4 [011̅]//α-Al2O3 <1̅100 > . The average transmittance of the ZnGa2O4 film in the visible region surpassed 83.1 %. The optical bandgaps of the ZnGa2O4 films annealed at 400, 500 and 600 °C were calculated to be 5.13 eV, 5.12 eV and 5.15 eV, respectively, which were much higher than the value of the as-deposited one (4.65 eV).

Micro-strain governed photoluminescence emission intensity of sol-gel spin coated Eu doped ZnO thin films

The objective of the present study is to analyze the role of surface free energy and microstrain on optical properties of Eu- (1, 2, 3, 5 and 6 at.%) doped sol-gel spin coated ZnO film on glass substrates. X-ray diffraction results revealed the presence of (100) plane indicating highly oriented monocrystalline film. The crystallite size was in the range of 43 to 86 nm, and the microstrain in ZnO thin films decreased from 0.00079 to 0.00040 with Eu doping. UV–vis transmission indicated transparency of 80 to 95 percent with a dip at 377 nm for undoped ZnO, which was slightly displaced to 380 nm on doping with Eu. The reduction in band gap values calculated using Tauc's plot was in the range of 3.33 to 3.17 eV. The photoluminescence (PL) emission spectra demonstrated unaltered UV emission peak on doping with Eu, however, the reduction in PL intensity was governed by microstrain induced in ZnO thin film by Eu doping. PL intensity and microstrain both decreased with Eu doping up to 3 at.%, then increased for Eu 5 at.% and eventually decreased again for Eu 6 at.%. Field emission scanning electron microscopy results exhibited a variety of irregular multi-dimensional morphological characteristics. Rectangular, square, and spherical structures were observed in 1, 2, 5, and 6 at.% Eu doped ZnO thin film. In contrast, 3 at.% Eu doping revealed long chain linkage structures that stuck together. The water contact angle measurements established the hydrophilic nature of all the doped-films. The reduced surface free energy was implied by decreased contact angle for Eu doped ZnO thin films (1, 2, and 3 at.%). This result suggested that surface free energy can be tuned with the Eu-content in ZnO. Such synergistic optical and mechanical features in ZnO based materials can give opening to diverse applications ranging from brain inspired neural network to reduction of power consumption.

Optimal parameter assessment of Solar Photovoltaic module equivalent circuit using a novel enhanced hybrid GWO-SCA algorithm

Solar Photovoltaic (PV) modules provide a reliable and clean electricity source that can suit various applications. Based on the quality and type of crystals, the PV modules are classified as monocrystalline, polycrystalline, and thin film. The improvements on different solar PV modules can be made efficiently with accurate mathematical models, which requires extracting its parameters. This paper suggests a novel enhanced hybrid grey wolf optimizer-sine cosine algorithm (EHGWOSCA) to extract solar PV module parameters. The recommended algorithm is validated on CEC-C06 2019 benchmark functions which contain ten standard functions. The PV module parameter extraction is performed on different kinds of PV modules, namely, monocrystalline type Shell CS6K280M, polycrystalline type Shell S75, and thin-film type Shell ST40. Two well-known models of PV modules are considered with a requirement of 5 parameters and 7 parameters extraction. The proposed algorithm is implemented by minimizing the sum of squared errors at open circuit point, short circuit point, and maximum power point (MPP). The results obtained show that in the Monocrystalline model using the proposed hybrid approach with single diode model, an error is 1.0718E−15, and it is further reduced to 1.3229E−16 with the double diode model. The proposed EHGWOSCA Error in the Polycrystalline model with double diode is 6.1594E−19, and the Thin-film model error is 2.91E−22. The effectiveness of the proposed approach is verified by comparative analysis with other methods available in the literature.

Deposition of high-quality Ge film on Si by PECVD using GeCl4/H2 for fabricating near-infrared photodiodes

Direct deposition of high-quality Ge film on Si substrate suitable for fabricating Ge/Si photodiodes was achieved by using plasma-enhanced chemical vapor deposition (PECVD) with GeCl4/H2 as precursors. A tensile-strained, impurity-free, monocrystalline Ge film with a surface roughness of < 1 nm and a threading-dislocation density on the order of 104 cm−2 could be grown at a rate of ca. 80 nm/min at a substrate temperature of 450 °C directly without the need of any kind of buffer layer or post-annealing. When applied to fabricate near-infrared (NIR) photodiodes, a low dark current density and a reasonably good responsivity for the employed photodiode architecture were attained, revealing the potential of this low-temperature fabrication method in monolithic integration of optoelectronic components with Si-based electronic circuits. The success of this technique may be attributed to an atomic-layer-deposition-like process for both nucleation and growth.

Photovoltaic Performance Using Modify Back Propagation Neural Network Based On 3 Different Solar Panels

Depletion of natural resources and increasing demand of power, sustainable energy sources such as photovoltaics (PV) are becoming increasingly more reliable and important. However, the production PV output power is unable to meet in terms of supply and demand due to irregular of solar irradiance and temperature daily. Therefore, a proper method/tool of prediction is very crucial to manage photovoltaic performance system and optimize the corresponding energy management system. In this paper, the modified Back Propagation Neural Network (BPNN) architecture is investigated. The investigating was conducted to provide more accurate prediction and error for short-term period prediction. The networkcompromises of 2 inputs parameter; the module temperature and solar irradiance and 1 output parameter; AC Power. Early research was conducted based on forecast time period on May 2021 starting from 7am to 8pm (14 hour) daily from 3 different panels; monocrystalline, polycrystalline and thin film, which are located on the rooftop of PEARL lab building. The result obtained shows that polycrystalline panel performed the best compare to monocrystalline and thin film panels.

Solar photo voltaic module parameter extraction using a novel Hybrid Chimp-Sine Cosine Algorithm

ABSTRACT The research on deriving accurate equivalent circuit of solar photovoltaic (PV) modules is increasing due to the necessity of constructing efficient energy conversion devices. The PV panel manufacturers provide data on three essential points on current–voltage (I–V) characteristics for standard temperature conditions (STC). Hence, the research on PV modules for different environmental/operational conditions with equivalent mathematical models are quite complex. Therefore, there is a necessity to derive accurate PV equivalent circuit parameters using novel AI-based approaches. This work proposes a novel hybrid meta-heuristic algorithm, hybrid Chimp-Sine cosine algorithm (HCSCA), for PV panel equivalent circuit parameter extraction. A well-known single- and double-diode PV models have been investigated with the proposed algorithm for different categories of PV modules, namely monocrystalline, polycrystalline, and thin film. The parameters derived from the proposed approach result in minimum error over different executions in the order of less than 10−10, which recommends better implementation in the present scenario. The nature of extracted parameters and I–V characteristics of considered PV panels are examined over different runs, which provided satisfactory performance characteristics with the proposed algorithm and recommended for its practical implementation.

Microstructure-dependent phase stability and precipitation kinetics in equiatomic CrMnFeCoNi high-entropy alloy: Role of grain boundaries

The multi-principal element CrMnFeCoNi alloy, which solidifies as a single-phase solid solution with the face-centered cubic (fcc) structure, is thermally stable above 900 °C but is known to decompose into multiple phases at temperatures between 450 and 800 °C. Although the thermal stability of Cr-Mn-Fe-Co-Ni alloys can be altered by changing the composition, there is limited knowledge of the role of microstructure on the kinetics of precipitation from the supersaturated primary fcc phase. To fill this gap, we compared the thermal stability of monocrystalline and polycrystalline thin films of the equiatomic CrMnFeCoNi alloy during synthesis and after post-deposition annealing. At the processing temperature of 700 °C, the polycrystalline film undergoes substantial phase decomposition in 3 min, consistent with earlier results that a bulk alloy of similar composition decomposes into multiple phases at this temperature. In contrast, the monocrystalline film of the same composition remains single-phase both during synthesis and subsequent annealing at 700 °C for 5 h. X-ray diffraction investigations together with comprehensive transmission electron microscopy analysis revealed that the decomposition of the supersaturated primary phase is related to the presence of structural defects, in particular grain boundaries, which promote diffusion of Cr and Mn and subsequently destabilize the primary solid solution. Correspondingly, the absence of high-diffusivity grain boundaries in the monocrystalline alloy prevents its primary phase from decomposing. The fundamental role of grain boundaries on precipitation kinetics, manifested through the short circuiting of sluggish bulk diffusion in entropy-stabilized multi-principal element alloys, is discussed together with the possibility of controlling their thermal stability by microstructural design.

Design of Photovoltaic as Energy Source at Government Office in Pangkalpinang

In the regulation of the general energy plan for the Bangka Belitung region, it is targeted that the total use of new and renewable energy will reach 17.21% in 2025 and 30.97% in 2050. This, of course, requires a measurable implementation to achieve this. In this regard, a photovoltaic design was carried out as a source of electrical energy in one of the government offices in Pangkalpinang. This office's daily demand for electrical energy is 78.79 kWh, with an average solar irradiance of 487.51 W/m2 and a measured ambient temperature of 26o – 33.3o C. The modeling is carried out using three types of photovoltaic panels, a namely polycrystalline, monocrystalline and thin film with a supply power is combined with a source from PLN and 100% photovoltaic

Performance analysis of mono crystalline, poly crystalline and thin film material based 6 × 6 T-C-T PV array under different partial shading situations

The selection of proper encapsulation material plays a vital role in design and development of PV modules for achieving good performance. Characteristics of a selected PV module material show great impact on electric yield, long term durability, processing of modules and cost. A high thermal conductivity material removes the generated heat fast and it helps in reducing operating temperatures of PV modules there by improvement in electric yield. Proper material selection, partial shadings, solar irradiance, temperature, aging effect, etc. has high impact on the quality of PV systems. Certain cells or modules in a PV array are shadowed by passing clouds, trees, poles, buildings, bird droppings, and other objects in partial shading conditions (PSCs), also known as mismatch situations. Under PSCs, Total-Cross-Tied (TCT) PV array configuration generates more Global maximum Power (GMP) compared to other configurations like series-parallel, Honey-Comb and Bridge-Link. Total-Cross-Tied PV array configuration can be formed by connecting cross ties in between the strings to improve the global maximum power from PV array. In this paper, the performance analysis of mono crystalline, poly crystalline and thin film material based 6 × 6 T-C-T PV array topology under various partial shading conditions has been investigated. To check the efficacy of the material considered for the PV array, the performance measures like mismatch losses, fill factor, Global Maximum Power Point and conversion efficiency have been used.

КВАНТОВЫЙ РАЗМЕРНЫЙ ЭФФЕКТ В СВЕРХПРОВОДНИКАХ

In the middle of the last century, it was demonstrated that with a decrease in the size of superconducting structures, for example, the thickness of a thin film, its critical temperature TC shifts by a certain amount. It increases in aluminum, tin, and indium, and decreases in mercury, niobium, and lead. However, there is still no generally accepted theory explaining this effect. In the 1970s, during the largest volume of research on this topic, V.L. Ginzburg assumed that the transition temperature of a sufficiently pure, monocrystalline superconductor film will be exactly the same as in a bulk body. However, this assumption has not yet been verified, and the question about the nature of this effect still remains open. For the study, we chose aluminum, due to the fact that the dependence of TC of the film on its thickness is very predictable and increases with decreasing size. Despite a number of works on studying this dependence in aluminum, it is not always possible to accurately establish a correspondence with a theory. This is because characteristics vary from sample to sample, even made in the same batch. In our case, polycrystalline films were prepared, the crystallite sizes in which are comparable to the film thickness, and epitaxial samples with an atomically smooth surface. The films were fabricated using electron-beam deposition and molecular-beam epitaxy on various substrates. Within the BCS model, the critical temperature of the superconducting transition exponentially depends on the density of electronic states at the Fermi level N ( EF ) and the electron-phonon interaction constant V : TC ~ exp(-1/[ N ( EF )* V ]). It is shown in this work that, due to QSE in thin superconducting films, both parameters N ( EF ) and V change nonmonotonically with the sample thickness. This behaviour is a consequence of the form resonance theory. Presumably, the effect caused by disordering of crystallites, as well as by the surface or substrate, does not play a dominant role specifically in our case, since the aluminum films are of high quality, and their thicknesses go far beyond the limits of ultrathin objects, in which surface phenomena become of decisive importance. As a result of this study, the experimental and theoretical dependences of TC on the thickness of films prepared by different methods on different substrates were obtained.

Performance Evaluation of Various Photovoltaic Module Technologies at Nawabshah Pakistan

The purpose of this study was to evaluate the influence of module temperature on the efficiency of polycrystalline (p-Si), monocrystalline (m-Si), amorphous (a-Si) and thin film photovoltaic modules at outdoor environment of Nawabshah city Pakistan. The experimental setup was made and installed over the top roof of departmental building. Weather conditions, such as global solar radiation, ambient temperature, wind speed and relative humidity, power output and temperature of all selected four types of module technologies were measured at the site by logging data. Then, the logged data was normalized because of different rated power of photovoltaic modules for comparison purpose. Results revealed that less temperature impact was noted from thin film module and thus it gave more normalized power with 45.6% among other examined modules. On the basis of overall efficiency, p-Si, m-Si, a-Si and thin film modules gave 92.4%, 93.7%, 94.4% and 95.4% yearly average normalized efficiencies respectively. It was found that temperature has more impact on the efficiency of other examined modules compared to thin film modules. Thus, it is concluded from the study that thin film module is better in outdoor environment of Nawabshah

Parameter extraction of solar cell using intelligent grey wolf optimizer

The focus of power producers has shifted from conventional energy sources to sustainable energy sources because of the depletion of fossil fuels and carbon emission causing global warming and climate change. Solar cells are the most prominent option to deal with these problems. The precise estimation of solar cell parameters is very much required before their installation to achieve high efficiency. In recent years applications of several optimization algorithms for parameter estimation of the solar cell have been addressed. Recently, intelligent grey wolf optimizer (IGWO), which is an advanced version of grey wolf optimizer (GWO) incorporating a sinusoidal truncated function as a bridging mechanism and opposition based learning has been introduced. The wide applicability of this variant has been examined over different conventional benchmark functions and on some real problems. This fact motivated authors to employ this variant on parameter extraction process. The main motivation behind the implementation of IGWO on solar cell parameter estimation process is the efficiency of this version to deal with complex optimization problems. To estimate the PV cell parameter values, measurement of voltage and current are considered at three important points. These are open circuit point, short circuit point and maximum power point, for two solar cell representative models i.e. single diode model and double diode model. Results of IGWO are compared with the results of other variants of GWO on these two models and for three films (Mono crystalline, poly crystalline and thin film). Results reveal that IGWO produces better results.