Shunt Resistance Rsh Research Articles

Structurally modified bacteriorhodopsin as an efficient bio-sensitizer for solar cell applications.

Structurally modified bacteriorhodopsin (BR) was prepared by simple surfactant treatment using Cetyl trimethylammonium bromide (cationic; CTAB), Sodium dodecyl sulphate (anionic; SDS) and Triton X-100 (nonionic; TX-100). In the UV-visible absorption spectrum, the characteristic absorption band of native BR at 560nm is hyperchromically (CTAB, due to induced aggregation), bathochromically (SDS, BR solubilisation and partial unfolding) and hypsochromically (TX-100, BR monomerizes) shifted after chemical treatment and the structural modifications were further confirmed by Raman spectra. Theoretical calculations based on optical absorption support an enhancement of BR optical and electrical conductivity via structural modification. Bio-sensitized solar cells (BSSCs) with structurally altered BR as sensitizer were fabricated and their photovoltaic performance was measured. We obtained the maximum short-circuit photocurrent and photoelectric conversion efficiency with TX-100-treated BR (0.93mAcm-2, 0.47%), with a quasi-Fermi level and a 124-ms lifetime of photogenerated electrons in TX-100-treated BR-sensitized BSSCs, two times higher than that observed in BSSCs with native BR. A single-diode equivalent circuit model reveals favorable BSSC parameters such as high reverse saturation current (I0 = 55 nA), low series resistance (Rs = 22.9 Ω) and high shunt resistance (Rsh = 3765.5 Ω) with TX-100-treated BR-based BSSCs. As TX-100 does not alter the BR carboxyl terminus during its monomerization, maximum anchoring to the BSSC occurs which results in enhanced photocurrent generation. Thus, monomerized BR-sensitized BSSCs with their excellent photovoltaic parameters suggest the possibility of replacing native BR with TX-100 BR and this opens up the possibility of reduced cost manufacture of bio-sensitized solar cells.

Synthesis, characterization and optical properties of multi-walled carbon nanotubes/aniline-o-anthranilic acid copolymer nanocomposite thin films

Carboxylic functionalized multi-walled carbon nanotubes/aniline-anthranilic acid copolymer composites with different amounts of MWCNTs were produced by the method of in situ oxidative polymerization. Thin films of the composites were fabricated by thermal evaporation method within the thickness range of 150–200 nm. The structural characteristics of the investigated composites were studied by various techniques. SEM images showed that the resulting nanoparticles have irregular entangled like-plate layers with an average diameter range of 40–60 nm. Indirect optical band gaps Eg1 and Eg2 were calculated depending on the energy range of composite thin films. Electronic parameters of MWCNTs/PANAA thin film, including diode ideality factor (n), series resistance (Rs) and shunt resistance (Rsh) were determined from the I–V characteristic in the dark under different temperatures. The values of n, Rs, and Rsh were found to be 3.80, 5.6 × 104 (Ω), and 1.64 × 106 (Ω), respectively at room temperature.

Pre-deposition of CdS layers to improve the diode quality of CZTSSe solar cells

The CdS layers are vital for diode quality of cell devices, which have great influences on high-performance CZTSSe solar cells. Optimizing the deposition processes of CdS layers are necessary to improve the diode quality and device efficiency. In this work, CZTSSe solar cells were fabricated without and with pre-deposited CdS layers, which are referred to as one-step and two-step processes, respectively. Then the performances of the CZTSSe solar cells were comparatively studied. Comparing with one-step processes, the efficiency of the solar cell by two-step processes improves from 7.24% to 9.45%. The efficiency improvement is mainly due to the gain of fill factor (FF) from 60.3% to 73.1%. Although the cell devices by different CdS processes have similar levels of interface recombination deduced from the activation energy (Ea), the temperature-dependent ideality factor A and shunt resistance (Rsh) indicate that the device fabricated by two-step possess higher diode quality and lower leakage current, which results in the increase of FF and efficiency. The optimization of CdS layer preparation is an effective approach to improve the efficiencies of solar cells.

Enhanced performance of amorphous silicon solar cells (110 °C) on flexible substrates with a-SiC:H(p) window layer and H2 plasma treatment at n/i and i/p interface

The a-Si:H based n-i-p solar cells were fabricated on flexible polyethylene terephthalate (PET), polyimide (PI) and rigid glass substrates with a-SiC:H(p) as a window layer using radio frequency plasma enhanced chemical vapor deposition technique. The effect of methane flow rate (MFR) on the structural and optoelectronic properties of a-SiC:H(p) films deposited at a low substrate temperature (Ts) 110 °C were studied on Corning 1737 glass (glass) substrate. The influence of hydrogen plasma treatment (HPT) at n/i and i/p interface of solar cells was also investigated. The HPT at interfaces was found to minimize interface defects and enhance the optical and electrical properties of the solar cell. The solar cell with a-SiC:H(p) as a window layer with HPT at interfaces have shown improvement in the series resistance (Rs), shunt resistance(Rsh), open circuit voltage (Voc) and fill factor (FF) as compared to the solar cells fabricated with conventional a-Si:H(p). The efficiencies of fabricated solar cell at 110 °C on flexible PET and PI are 3.36 and 4.06%, which is close to 4.42% on rigid glass. Our results demonstrate that, a-SiC:H(p) as a window layer with HPT at n/i and i/p interfaces can be considered as a practical method to produce the a-Si:H based solar cells on low cost flexible substrates at low substrate temperature.

Degradation analyses of GaInP/GaAs/Ge solar cells irradiated by 70 keV and 150 keV protons by current-voltage curves under various intensities of light

Abstract Low energy protons damage GaInP/GaAs/Ge solar cells seriously. Traditional degradation researches require many supplementary tests, such as quantum efficiency (QE) or photoluminescence (PL). In this paper, we would establish a method that could analysis degradation of solar cells without any other equipment except a solar simulator. A voltage-current analysis technique under various intensities (X) of light was developed to study the degradation mechanisms of proton-irradiated GaInP/GaAs/Ge solar cells. Sum of ideality factor of every sub-cell Σni could be calculated from the change of open circuit voltage (Voc) with light intensities in multi-junction solar cells. The change of ideality factor shows significant increase of Shockley-Read-Hall (SRH) recombination after 70 keV and 150 keV protons irradiation. Shunt resistance Rsh increases with intensities, which is different from silicon solar cells. The change of Rsh with light intensities was used to describe the current mismatch among the sub-cells in the multijunction solar cell. After irradiation, the current mismatch becomes larger. The relative degradation rate is different under different intensities of light. The max-power degradation tends to be smaller at high intensities.

Spectroscopic Limited Practical Efficiency (SLPE) model for organometal halide perovskites solar cells evaluation

Abstract Spectroscopic Limited Maximum Efficiency (SLME) model is a powerful tool to estimate theoretical PCEs of solar cells, in which AM1.5G and DFT calculated absorption spectra are two important input parameters and an ideal diode circuit is used. However, SLME is an entirely theoretical model and just puts forward a maximum PCE, and it is difficult to evaluate the practical devices and move in the positive direction to reach the maximum PCE. We improved SLME and developed Spectroscopic Limited Practical Efficiency (SLPE) model by replacing the two input parameters with the light source spectrum of solar simulator used in the experiment and the absorption spectra measured by ellipsometry, and the equivalent circuit was also changed to a classical equivalent circuit with a diode and resistances. By using SLPE, 5597 sets of I-V data for 26 different types of hybrid lead iodide perovskite devices were fitted and five output parameters, current coefficient f1, voltage coefficient f2, diode ideality factor n, series resistance RS and shunt resistance RSH, which quantify the difference between the actual I-V curve and the ideal one for a practical perovskites solar cell, were obtained. The analysis of the output parameters indicated that RSH was close to the ideal value followed by f2, n and f1, but RS performed large difference due to the different carrier mobility of HTL. For HTL with carrier mobility less than or equal to 10−5 cm2V−1s−1, ∼10−4 cm2V−1s−1 and ∼10−3 cm2V−1s−1, RS is larger than 103 Ω, 102–103 Ω and 101–102 Ω, leading to the devices loss more than 85%, 20–85% and less than 20% efficiency, respectively. SLPE model offers a systematic analysis tool to understand and quantify efficiency loss of perovskite solar cells.

Improving effect of poly (linolenic acid)–g–poly (caprolactone)–g–poly (t-butyl acrylate) interfacial layer on Au/n-Si diodes

Poly (linolenic acid)-g-poly (caprolactone)-g-poly (t-butyl acrylate) (PLilPCLPtBA) graft copolymer was used as an interfacial layer in Au/n-Si Schottky diode. The novel PLilPCLPtBA layer was coated on n-Si single crystal wafer through an electrospinning system. Nanofiber characteristics of the PLilPCLPtBA layer was obtained by a Field Emission Scanning Electron Microscope (FEG-SEM). The current–voltage (I–V) measurements of these Au/n-Si diodes with and without polymeric layer were conducted in dark and under various illumination intensity levels (halogen lamp) at room temperature. Main electrical parameters such as series resistance (Rs), shunt resistance (Rsh), ideality factor (n), reverse saturation current (Io), zero-bias barrier height (Φbo) and interface state density (Nss) of the structures were extracted from forward-bias I–V data.

Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 2: application to experimental IV measurements and comparison with other methods

In this Part 2 of this series of articles, the procedure proposed in Part 1, namely a new parameter extraction technique of the shunt resistance (Rsh) and saturation current (Isat) of a current-voltage (I–V) measurement of a solar cell, within the one-diode model, is applied to CdS-CdTe and CIGS-CdS solar cells. First, the Cheung method is used to obtain the series resistance (Rs) and the ideality factor n. Afterwards, procedures A and B proposed in Part 1 are used to obtain Rsh and Isat. The procedure is compared with two other commonly used procedures. Better accuracy on the simulated I–V curves used with the parameters extracted by our method is obtained. Also, the integral percentage errors from the simulated I–V curves using the method proposed in this study are one order of magnitude smaller compared with the integral percentage errors using the other two methods.

Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 1: a new theoretical procedure and comparison with other methodologies

A new proposal for the extraction of the shunt resistance (Rsh) and saturation current (Isat) of a current-voltage (I–V) measurement of a solar cell, within the one-diode model, is given. First, the Cheung method is extended to obtain the series resistance (Rs), the ideality factor (n) and an upper limit for Isat. In this article which is Part 1 of two parts, two procedures are proposed to obtain fitting values for Rsh and Isat within some voltage range. These two procedures are used in two simulated I–V curves (one in darkness and the other one under illumination) to recover the known solar cell parameters Rsh, Rs, n, Isat and the light current Ilig and test its accuracy. The method is compared with two different common parameter extraction methods. These three procedures are used and compared in Part 2 in the I–V curves of CdS-CdTe and CIGS-CdS solar cells.

A new method to extract the equivalent circuit parameters of a photovoltaic panel

This paper offers a new method to extract the equivalent circuit parameters of a single diode photovoltaic (PV) panel. These parameters were determined by using the manufacturer data of the PV panel and an experimental measurement. This method consists in measuring a single parameter which is the shunt resistance Rsh, the other unknown parameters were determined through the resolution of the equations proposed by the method. The strength of the proposed method is that the measurement errors do not affect the values of the calculated parameters. In order to confirm the accuracy of the current work, this method is applied on two different types of solar panels (monocrystalline and polycrystalline). And thereafter, the corresponding power-voltage (P-V) and current-voltage (I-V) curves are compared to manufacturer, PVsyst software and to the results achieved by other authors for various levels of temperature and irradiance. The results indicated that the proposed method is simple, fast and offers accurate results which make it applicable to different types of PV panels.

Modification of back electrode with WO3 layer and its effect on Cu2ZnSn(S,Se)4-based solar cells

In the present work, we designed and prepared Cu2ZnSn(S,Se)4 (CZTSSe)-based solar cells with a new structure of Al/ITO/ZnO/CdS/CZTSSe/WO3/Mo/SLG (S1-5) by depositing about 5-nm-thick WO3 layer with monoclinic structure on the back electrode Mo/SLG of solar cells with the convention structure of Al/ITO/ZnO/CdS/CZTSSe/Mo/SLG (S2), with the aim of improving the power conversion efficiency (PCE) of CZTSSe-based solar cells. It is found that the average open circuit voltage (Voc) increases from 346.7 mV of the S2 cells to 400.9 mV of the S1-5 cells, the average short circuit current density (Jsc) from 26.4 mA/cm2 to 32.1 mA/cm2 and the filling factor (FF) from 33.8 to 40.0 by addition of the WO3 layer, which results in that the average PCE increases from 3.10% of the S2 cells to 5.14% of the S1-5 cells. The average increasing percent of the PCE is 65.8%. The increase in Voc, Jsc and FF of the S1-5 cells compared to the S2 cells is attributed to that the WO3 layer prevent the Se coming from Se ambient and CZTSSe to react with the Mo to form MoSe2 and other second phases, which makes the shunt resistance (Rsh) of the S1-5 increase and the series resistance (Rs) and reverse saturation current density (J0) decrease compared to the S2 cells. The decreased J0 is main factor of improvement of the PCE. A mechanism of influence of the Rsh, Rs and J0 on the PCE is also revealed. Our result demonstrates that addition of the WO3 layer with a reasonable thickness can be a promising technical route of improving the PCE of the CZTSSe-based solar cell.

Influence of the Preparation Method on Planar Perovskite CH3NH3PbI3-xClx Solar Cell Performance and Hysteresis

Abstract Organometal halide perovskites are promising materials for lowcost, high-efficiency solar cells. The method of perovskite layer deposition and the interfacial layers play an important role in determining the efficiency of perovskite solar cells (PSCs). In the paper, we demonstrate inverted planar perovskite solar cells where perovskite layers are deposited by two-step modified interdiffusion and one-step methods. We also demonstrate how PSC parameters change by doping of charge transport layers (CTL). We used dimethylsupoxide (DMSO) as dopant for the hole transport layer (PEDOT:PSS) but for the electron transport layer [6,6]-phenyl C61 butyric acid methyl ester (PCBM)) we used N,N-dimethyl-N-octadecyl(3-aminopropyl)trimethoxysilyl chloride (DMOAP). The highest main PSC parameters (PCE, EQE, VOC ) were obtained for cells prepared by the one-step method with fast crystallization and doped CTLs but higher fill factor (FF) and shunt resistance (Rsh ) values were obtained for cells prepared by the two-step method with undoped CTLs.

Analysis of electrical properties of heterojunction based on ZnIn2Se4

Heterojunction of n-ZnIn2Se4/p-Si was fabricated using thermal evaporation of ZnIn2Se4 thin films of thickness 473 nm onto p-Si substrate at room temperature. The characteristics of current–voltage (I-V) for n-ZnIn2Se4/p-Si heterojunction were investigated at different temperatures ranged from 308 K to 363 K. The junction parameters namely are; rectification ratio (RR), series resistance (Rs), shunt resistance (Rsh) and diode ideality factor (n) were calculated from the analysis of I-V curves. The forward current showed two conduction mechanisms operating, which were the thermionic emission and the single trap space charge limited current in low (0 ≤ V ≤ 0.5 V) and high (V ≥ 0.7 V) ranges of voltage, respectively. The reverse current was due to the generation through Si rather than the ZnIn2Se4 film. The built-in voltage and the width of the depletion region were determined from the capacitance-voltage (C-V) measurements. The photovoltaic characteristics of the junction were also studied through the (I-V) measurements under illumination of 40 mW/cm2. The cell parameters; the short-circuit current, the open-circuit voltage and the fill factor were estimated at room temperature.

Effect of Measurement Factors on Photovoltaic Cell Parameters Extracting

In this paper, we study the influence of external factors on the measurement for the current–voltage (I-V) characteristic of the photovoltaic cell. These factors are the size of the number of measurements, the range of the cell generated voltage and the influence of measures step and mode combination of photovoltaic cells (parallel, serial, or hybrid). The main extracted parameters solar cell are the photocurrent Iph, the reverse diode saturation current I0, the ideality factor of diode n, the series resistance Rs and the shunt resistance Rsh. A method for finding these parameters, according to the single-diode model, was developed by Newton-Raphson’s method using Matlab. To assess the accuracy of this method, measured and calculated I–V characteristics were compared with provided data by the manufacturer at standard test condition (STC). The measurement results showed that these parameters are highly dependent on these four factors.

Effect of layer thickness on the electrical parameters and conduction mechanisms of conjugated polymer‐based heterojunction diode

ABSTRACTIn this study, thickness‐dependent current density–voltage (J–V) characteristics obtained for poly{(9,9‐dioctylfluorene)−2,7‐diyl‐(4,7‐bis(thien‐2‐yl) 2‐dodecyl‐benzo[1,2,3] triazole)} (PFTBT) conjugated copolymer based heterojunction diode fabricated on ITO were investigated in terms of electrical characteristics. In order to analyze J–V plots with ITO/PEDOT:PSS/PFTBT:PC61BM/LiF/Al configuration, the thickness‐dependent J–V measurements were applied in the thickness range between 90 and 200 nm. The effect of PFTBT:PC61BM layer thickness on the forward J–V characteristics were investigated by evaluating electrical parameters such as zero bias barrier height (ΦBo), ideality factor (n), shunt resistance (Rsh), series resistance (Rs), the interface states density (Nss), and space‐charge limited mobility. The results show that at PFTBT:PC61BM layer thickness of 90 and 200 nm, ideality factor for ITO/PEDOT:PSS/PFTBT:PC61BM/LiF/Al heterojunction diodes ranged from 2.726 to 3.121 and the thermionic emission over the heterojunction diodes is crucial at low current densities and the intrinsic thermally generated charge carriers controlled the forward current this region of the heterojunction diode. At relatively higher voltage, the current mechanism of ITO/PFTBT:PC61BM/PEDOT:PSS/LiF/Al heterojunction diodes were found to obey a space charge limited (SCLC) conduction mechanism. The values of Nss and Rs in heterojunction diodes increase with increasing PFTBT:PC61BM layer thickness and effect the main electrical parameters of diodes. In addition, the leakage current of heterojunction diodes are taken and interpreted via Poole‐Frenkel emission and Schottky emission. The leakage current was controlled in ITO/PEDOT:PSS/PFTBT:PC61BM/LiF/Al heterojunction diodes by Poole‐Frenkel emission above 140 nm and by Schottky emission under 140 nm. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44817.

Fabrication and Characterization of Front-Illuminated Dye-Sensitized Solar Cells with Anodic Titanium Oxide Nanotubes

We have fabricated front-side illuminated dye-sensitized solar cells (DSSCs) with a thin film of vertically oriented TiO2 nanotubes used as the negative electrode. The TiO2 nanotube film was formed by anodizing a metallic titanium thin film that was deposited on a transparent conductive oxide (TCO) layer with an intermediate, protective TiO2 layer. We characterized the structural and electronic properties of the formed TiO2 nanotube films. Titanium tetrachloride (TiCl4) treatment was applied on the TiO2 nanotube film to improve the performance of the DSSCs. We have investigated effects of TiCl4 treatment on the solar cell parameters of the DSSCs: short-circuit current density (ISC), open-circuit voltage (Voc), ideal factor (n), series resistance (Rs) and shunt resistance (Rsh). The parameters have been derived by analyzing measured I-V characteristic of the DSSCs on the basis of the method we have previously proposed. We demonstrate that the performance of the DSSCs is improved by TiCl4 treatment. We discuss the effects of TiCl4 treatment on the performance on the basis of the derived cell parameters.

Structure, optical, electrical and electronic parameters of a new thin film composition for kesterite solar cell

The work is devoted to the development of a new thin film composition for kesterite solar cell with the base Cu2ZnSnS4 (CZTS) layer obtained by the combination of two low-cost liquid methods, namely electrodeposition and Successive Ionic Layer Adsorption and Reaction (SILAR). The p-CZTS absorber is fabricated by the creation of the main Cu2ZnSnS4 layer through sulfurization of a stack of the electrodeposited Cu/Sn/Zn metal films. The pores in this main Cu2ZnSnS4 layer were filled by SILAR-deposited nanocrystalline kesterite layer. For a creation of semiconductor heterojunction n-ZnS/p-Cu2ZnSnS4 we prepared ZnS thin films by SILAR method. The work shows the results of analysis of diode characteristics of the developed ZnS/Cu2ZnSnS4 heterostructures (series resistance Rs, shunt resistance Rsh, ideality factor nd and the saturation current densities Jo). Other investigated electrical and electronic parameters obtained from the current-voltage (I-U) and capacitance-voltage (C-U) characteristics are the electrical resistivities ρCZTS and ρZnS, the ZnS/Cu2ZnSnS4 rectifying barrier Φ, the height φ of symmetrical double Schottky barriers in the grain boundary regions in the polycrystalline kesterite layers, the width of the electron depletion regions ω, the concentration of the fully ionized donor impurity Nd in n-ZnS and acceptor impurity Na in p-Cu2ZnSnS4, the density NSS of the surface states in the kesterite layers. Structure and optical properties of the ZnS films as such as of the individual kesterite layers and of their combination have been also researched.

Electrical properties of Al/PTB7-Th/n-Si metal-polymer-semiconductor Schottky barrier diode

In the present study, poly{4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophene-4,6-diyl} (PTB7-Th) was used to fabricate a novel Al/PTB7-Th/n-Si metal-polymer-semiconductor (MPS) Schottky barrier diode (SBD). The Al/PTB7-Th/n-Si MPS SBD was prepared by employing a spin-coating system and a thermal evaporator for the deposition of PTB7-Th thin film and metal contacts, respectively. The electrical properties of the Al/PTB7-Th/n-Si MPS SBD were investigated by current-voltage method at room temperature in order to extract its main electrical parameters such as ideality factor (n), barrier height (Φb0), series resistance (Rs) and shunt resistance (Rsh). The I–V characteristics revealed nonlinear behavior due to the effect of Rs and ideality factor larger than unity. From the I–V curves, the values of ideality factor and barrier height of the diode were found to be 3.5 and 0.58eV, respectively. The electrical parameters were verified by Cheung’s and Norde’s functions. The parameters determined by all the three methods were found to be in great agreement. The conduction mechanism of the diode was also studied. The simple and cost effective approach used for the fabrication of Al/PTB7-Th/n-Si MPS SBD demonstrates its potential for being used in the state-of-the-art high-quality electronic and optoelectronic devices.

A Two-Step Absorber Deposition Approach To Overcome Shunt Losses in Thin-Film Solar Cells: Using Tin Sulfide as a Proof-of-Concept Material System.

As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to reproducibly test promising candidates for high-performing PV devices. Many early-stage devices are prone to device shunting due to pinholes in the absorber layer, producing "false-negative" results. Here, we demonstrate a device engineering solution toward a robust device architecture, using a two-step absorber deposition approach. We use tin sulfide (SnS) as a test absorber material. The SnS bulk is processed at high temperature (400 °C) to stimulate grain growth, followed by a much thinner, low-temperature (200 °C) absorber deposition. At a lower process temperature, the thin absorber overlayer contains significantly smaller, densely packed grains, which are likely to provide a continuous coating and fill pinholes in the underlying absorber bulk. We compare this two-step approach to the more standard approach of using a semi-insulating buffer layer directly on top of the annealed absorber bulk, and we demonstrate a more than 3.5× superior shunt resistance Rsh with smaller standard error σRsh. Electron-beam-induced current (EBIC) measurements indicate a lower density of pinholes in the SnS absorber bulk when using the two-step absorber deposition approach. We correlate those findings to improvements in the device performance and device performance reproducibility.

Development of Mathematical Equation for Photovoltaic Array Internal Resistance Measurement under Operating Conditions

A novel technique has been developed for PV array internal resistance measurement while keeping the plant in operation in contrary to flash test or basic equation (Eb) for which the modules need to be disconnected from the system. We present an equation developed for the array’s internal resistance measurement for PV technologies namely Amorphous Silicon (a-Si), Poly Crystalline Silicon (p-Si) and Hybrid Crystalline Silicon (HIT). Monthly Measured I-V characteristic curves of PV Array were converted to Standard Test Conditions following the IEC 60891 standard. Multiple regression analysis and linear regression technique were used to develop the equation for estimating the PV array internal resistance. The developed equations (Ed) will find the relationships of the 4 variables that are Series resistance (Rs), Shunt resistance (Rsh), maximum voltage (Vm) and maximum current (Im). The results revealed that the Ed can be applied to measure the PV array internal resistance value with low error margin than Eb. The series resistance calculated using Ed is higher than Eb about 1.11 %, 1.88 % and 0.87 % for a-Si, p-Si and HIT respectively. The shunt resistance calculated using Ed is higher than Eb about 0.07 %, 0.09 % and 0.09% for a-Si, p-Si and HIT respectively.