ICMCTF2015 Session TSP: Symposium TS Poster Session

Thursday, April 23, 2015 5:00 PM in Room Grand Hall
Thursday Afternoon

Time Period ThP Sessions | Topic TS Sessions | Time Periods | Topics | ICMCTF2015 Schedule

TSP-1 Fabrication and Characterization of Highly Flexible Al2O3/Al/Al2O3 Hybrid Composite
Zhijiang Wang (Harbin Institute of Technology, China); Henry Hu, Xueyuan Nie, Fuyan Sun (University of Windsor, Canada)

The natural brittleness of oxide ceramics heavily inhibits their more extensive applications. By employing plasma electrolysis oxidation to in-situ grow alumina layers on Al foil, a highly flexible Al2O3/Al/Al2O3 hybrid composite was fabricated with a ductile Al substrate and an outside layer of nanostructured polycrystalline oxide ceramic of which the ceramic part is composed of nanosized grains with the size less than 20 nm. Due to shear band formation, nanosized circle bubbles prolonging the crack path, grain rotation and deformation, the fabricated Al2O3/Al/Al2O3 hybrid composite contains no observable cracks even after being bent on a cylindrical bar with a curvature of 1.5 mm. The composite exhibits alumina stiffness at the elastic stage and aluminum ductility during plastic deformation, which provides high flexibility with the well-integrated properties of the components. In a synergistic interaction, the alumina on the outside exhibited a strain of 0.33% at room temperature, which was higher than optimum value of 0.25% presented by reported most flexible oxide ceramic. With the unique characteristics and properties, the Al2O3/Al/Al2O3 composite demonstrates a great potential for engineering applications in various industries.

TSP-2 Modelling the Nanomechanical Responses of Biopolymer Composites During the Nanoindentation
Pengfei Duan, Jinju Chen (Newcastle University, UK)
Many empirical or semi-analytical models have been proposed to study how the elastic moduli of the coated systems changes with the penetration. However, little work has been done for the inclusion/matrix composite materials. Clifford et al proposed an alternative model to deal with this, but this model has more complicated fitting parameters. It appears that their model works better due to better fitting capability of their empirical mathematical equations. Therefore, we aim to examine if it is the case. Most of work developed empirical equations that correlated the relative penetration depth (i.e the ratio of indentation penetration and coating thickness) to the change of the relative Young’s modulus (i.e. normalized to the mismatch of Young’s modulus between the coating and substrate). In such case, their applications are only limited to certain coated systems. While Clifford et al adopted a new parameter which combines the relative penetration depth and the ratio of Young’s modulus between the coating and substrate. In this study, it is found that replacing the relative penetration depth with such a new parameter, all the previous models would work much better. Indeed, for the nanoindentation response of inclusion/matrix composite materials, a simpler model has been proposed, which works at least equally well but with less fitting parameters compared to the Clifford model.
TSP-3 Modelling the Morphology Effect on Determining the Mechanical Properties of Biofilm by Nanoindentation
Cécilia Geffroy (Polytech, Marseille, France); Jing Ma, Jinju Chen (Newcastle University, UK)

Biofilms are referred as microbial populations in a matrix of extracellular polymeric substances (EPSs) adhering to substrates. Many industries (e.g. maritime, water systems, dentistry and hospitals) suffer from the biofilm growth which can result in significant costs in cleaning and maintenance. On the other hand, biofilms can be useful in removing contaminants (e.g. metals, oil spills and nitrogen compounds) and for the purification of industrial waste water.

The mechanical properties of biofilms determine their resistance to stress and eventual dispersal mechanism. Similar to many other biological materials, biofilms also exhibit viscoelastic behaviour. To assess the mechanical properties of the intact soft biofilms, nanoindentation is one of the best techniques to use. For the motile bacteria growing at hydrodynamic environment, the typical biofilms are truncated ellipsoidal and mushroom-like shapes. Due to the complex morphology, it is not easy to obtain the reliable mechanical properties of the biofilms. Therefore, finite element modelling was adopted to study how the morphology of the biofilms would affect the determination of their viscoelastic properties.

TSP-5 Optical Properties and Electrical Transport in Nb-Ti-N Thin Films Deposited by Magnetron Sputtering
Rosendo Sanjines, Ana Martins, Ayat Karimi (Swiss Federal Institute of Technology Lausanne (EPFL), Switzerland); Nicolas Goebbels, Antonio Santana (IHI Ionbond AG, Switzerland)

A comprehensive characterization of the Nb(1-x)TixNy films is performed in order to shed light on the interrelated physicochemical and structural properties of these materials. The ternary Nb(1-x)TixNy (with 0≤x≤1 and 0.9<y<1.1) have been deposited onto Si substrates at temperatures around 400 °C by using reactive magnetron sputtering. The analysis includes XRD, AFM, TEM, SEM, EPMA, XPS, nanohardness and optical and electrical measurements. In this paper we report on the influence of chemical and structural properties on the electronic properties of Nb(1-x)TixNy films. The optical properties have been investigated by specular reflectivity and spectroscopic ellipsometry, and the electrical resistivity was measured by the van der Pauw method from 7 K to 300K. In the ternary nitrides the fcc rocksalt phase is the only phase observed. The dielectric function of these nitrides exhibits high sensitivity to the phase composition and in particular to the nitrogen content in the films allowing a complete and consistent description of the evolution of the Nb(1-x)TixNy films as a function of the chemical composition.

TSP-6 Retarding Field Analysis of the Ion Energy Distribution in a Large-area Capacitively Coupled Multi Frequency Plasma
Stefan Ries, Carles Corbella, Stefan Bienholz, Dario Grochla (Ruhr Universität Bochum, Germany); Julian Schulze (West Virginia University, USA); Alfred Ludwig, Achim von Keudell, Peter Awakowicz (Ruhr Universität Bochum, Germany)

Since 2010 the Institute for Electrical Engineering and Plasma Technology at the Ruhr-University Bochum has been investigating a large-area, capacitively coupled multi frequency plasma source (MFCCP) for deposition of ceramic layers.

The advantages of CCPs over the established magnetrons consists of a nearly 100% target utilization, a weak target poisoning, application of isolating (e.g. ceramic) and magnetizable (ferromagnetic) targets, a good homogeneity of the deposited layers on large areas and the capability for a separate control of the ion energy and the ion flux.

The main research objective is to understand the coherences between the plasma process parameters respectively plasma parameters and the properties of the deposited layers.

The MFCCP is powered by three frequencies 13.56 MHz, 27.12 MHz and 60 MHz. The two lower frequencies are driven in a phase locked mode with an adjustable phase shift. By varying the phase shift the dc self-bias respectively the ion energy onto the target can be changed very accurate without effect on the ion flux. The applied voltage at 60 MHz generates a high plasma density.

In recent investigations process parameters (e.g. dc selfbias) respectively plasma parameters (e.g. electron density, temperature, ion energy distribution) and its influence to the properties of aluminium nitride layers (e.g. thickness, stress) are examined by using various plasma diagnostics and coating analytics.

Particularly the impact of the ion energy on the growing Al and AlN-layers is studied by measuring the ion energy distribution (IED) with a retarded field energy analyser at different positions on the substrate electrode. The measurement is divided in three steps: First of all there are ion energy measurements in the MFCCP only with the classical frequency to get a first idea of the system. In the second step the plasma is additional driven with the second harmonic of the classical frequency to investigate the IED by using the electrical asymmetry effect. Finally the measurements are done by using all three frequencies of the MFCCP to obtain the plasma at higher electron density and ion flux. After all the results will be correlated with the Al and AlN-layer properties (e.g. thickness, stress).

The MFCCP is a sub-project of the collaborative research centre SFB-TR 87 funded by the German Research Foundation (DFG). We thank Dr. Carles Corbella and Prof. Dr. Julian Schulze for supporting the IED measurements and the inspiring discussions. We also thank the Institute of Materials (coating analytics) at the Ruhr-University Bochum for providing success for presenting the corporate results.

TSP-7 Fabrication and Characterization of Hybrid Photoelectrode for Dye-sensitized Solar Cells
JinSoo Lee, KyungHwan Kim, HyungWook Choi (Gachon University, Republic of Korea)

Dye-sensitized solar cells (DSSCs) have been intensively studied in many laboratories due to their relatively low cost, high light-to-electricity conversion efficiency, and easy fabrication compared to silicon based solar cell. Generally, DSSCs are composed of as parts titanium dioxide (TiO2) which carries an anchored organic dye on working electrode layer, counter electrode layer made of Pt and an electrolyte containing a redox couple (I-/I3-) between them.

However, a number of problems remain to be solved in order to improve their efficiency. In particular, one of the main limiting factors is the electron recombination that occurs due to contact between the transparent conductive oxide and the redox electrolyte.

For high efficiency solar energy conversion, the photoelectrode must facilitate effective light harvesting, electron injection, and reducing recombination of the photoinjected electrons. To avoid recombination, one of the strategies is to introduce a ZnO passivating layer to the FTO conducting glass/TiO2 interface. Several researches have introduced ZnO to reduce the recombination at electrode/electrolyte interface as having a more negative conduction band edge than TiO2. In addition, 1-dimensional TiO2 nanostructures have attracted need to avoid the limited electron transport in the nanocrystal boundaries of TiO2 nanoparticles and the electron recombination with the electrolyte during the electron migration process.

And, one method of increasing the efficiencies of DSSCs is to enhance their ability to harvest light. Commercially available dyes (N-719) only absorb in the wavelength range of 400–800 nm, and most of the ultraviolet region is not used. If ultraviolet radiation could be converted to visible light by a suitable conversion-luminescence process and reabsorbed by the dye of a DSSCs, a larger part of the solar irradiation could be used and the photocurrent of the DSSCs will be effectively enhanced.

Thus, we fabricated hybrid photoelectrode of TiO2 nanotube/phosphor mixed TiO2 nanoparticles on ZnO passivating layer in terms of dye adsorption, charge transport and reducing the electron recombination.

In this paper, we described the improvement in the photovoltaic characteristics of dye-sensitized solar cells by using a ZnO passivation layer, TiO2 nanotube/phosphor mixed TiO2 photoelectrode. The crystalline structure and morphology were characterized by X-ray diffraction and using a field emission scanning electron microscope. The absorption spectra were measured using an UV-Vis spectrometer. The incident photocurrent conversion efficiency was measured using a solar simulator (100 mW/cm2).

TSP-9 Study on AISI 4140 Hardened by Paste Dehydrated Boron
Daniel Sanchez Huerta (Tecnológico De Estudios Superiores De Cuautitlan Izcalli, México); Noe Lopez-Perrusquia, MarcoAntonio Doñu Ruiz (Universidad Politécnica del Valle de México, México); JorgeVictor Cortes Suarez (Universidad Autónoma Metropolitana Azcapotzalco, México); Filiberto Ortiz Meza (Universidad Politécnica del Valle de México, México)

In this research, the behavior of iron boride growth and adhesion of the coating formed on the surface of AISI 4140 steel by thermochemical treatment boriding, boride with paste, boxed dehydrated is studied temperature of 1273 °K and 1223 °K, with an exposure time of 2 to 0.5 h. Adhesion was evaluated by the Rockwell C technique prescribed by the German standard VDI 3198 adhesive. By light microscopy the morphology and growth rate of layer FeB / Fe₂B on the material surface, by exposure to boriding paste is observed. The presence of phases of boride FeB / Fe₂B were determined by X-ray diffraction (XRD). The technique of scanning electron microscopy (EDS) shows the distribution of the alloying elements on the FeB / Fe₂B / Subtrato layer formed on the surface of the material to study. The elastic modulus and hardness were obtained with the temperatures of 1273 °K and 1223 °K, with a time of 2 to 0.5 h for each temperature, nanoindentation technique on FeB / Fe₂B layers formed on the steel surface. Finally, this study determined the type of delamination layer / substrate, the distribution of the alloying elements on the FeB / Fe₂B / phases and mechanical properties FeB / Fe₂B AISI 4140 steel boriding, paste dehydrated boron. This study aims to contribute to the growth, morphology and behavior of boride formed in the boriding steel with dried paste.

TSP-10 Multiplexing Storage Using Angular Variation in Transmission Holographic PDLC
Eun-Hee Kim, Yeon-Gil Jung (Changwon National University, Republic of Korea)
Recently, much attention has been focused on holographic processes and development of novel materials for high-performance hologram. This is largely due to the need for expanding the information storage technology presently available. Holographic storage has long been the promise for large digital storage capacity because the information packing densities can be considerably increased by using three-dimensional storage techniques in the form of interference patterns. Holographic storage also enables fast data transfer because it permits reading and writing of data simultaneously. Simultaneous angular multiplexing of transmission gratings in a holographic polymer dispersed liquid crystal (HPDLC) film has been fabricated by exposing the materials to three coherent laser beams in response to resin and film compositions, irradiation intensity and cell thickness. It was found that the diffraction efficiency monotonically increases with irradiation intensity and cell gap, whereas a maximum of 43% is obtained at specific compositions of trimethylolpropane triacrylate (TMPTA)/N-vinyl pyrrolidone (NVP)=8/1, and polymer/LC=65/35. The multiplexed gratings have been captured by SEM image and the reconstructed images by CCD camera. The periodic structures of LC and polymer regions were well revealed and the reading of the recorded image was successfully reconstructed.
TSP-12 On the Early Growth Stages of Sputter-deposited Pd Films
Jonathan Colin, Grégory Abadias, Anny Michel, Christiane Jaouen, Cédric Mastail (University of Poitiers, PPRIME Institute, CNRS, France)

Metal silicide thin films are of technological relevance in silicon-based microelectronics devices, as they are largely used as ohmic contacts, Schottky barrier contacts, gate electrodes, or diffusion barriers. The mechanisms of silicide formation at the metal-silicon interface are relatively complex and depend on the nature of the metal as well as substrate orientation. Pd-Si is a model system because of the formation of a single silicide phase, Pd2Si, below 700°C. Extensive studies have been carried out to identify the dominant diffusing species and study the growth kinetics as well as stress development/relaxation processes during solid state reaction; however, the growth dynamics and stress build-up during thin film deposition of Pd on Si remains still largely unexplored.

In the present work, we have used in situ and real-time multiple beam optical stress sensor (MOSS) and four-probe resistivity measurements, combined with ex-situ (XRD, AFM, TEM) structural characterization, to investigate the early growth stages of sputter-deposited Pd thin films. The nucleation conditions were varied by depositing the Pd films on Si(001) wafers covered either by native SiO2 (~2 nm), amorphous a-Si (2 to 20 nm) or chemically etched with dilute HF. We also deposited Pd/Si and Pd/Ge multilayers to highlight the role of the interface. The influence of substrate temperature, up to 200°C, will be also discussed.

From the non-monotonous stress evolution recorded at room temperature (RT), different growth regimes have been evidenced: a 3D growth mode (islands nucleation and coalescence) for films grown on SiO2, and the formation of interfacial layer prior to the steady-state growth of pure Pd for films grown on a-Si. In all cases, the Pd films are strongly (111)-textured, the lowest mosaicity (2.2°) being surprisingly obtained on a-Si. XRD investigations on (a-Si/Pd)n [resp. (a-Ge/Pd)n] multilayers reveals that the interfacial layer corresponds to crystalline Pd2Si [resp. Pd2Ge] phase of ~2-3 nm thickness when deposition occurs at RT. At higher substrate temperature, competition between interfacial silicide formation and growth of fcc Pd takes place, the former process being limited by the initial thickness of a-Si layer.

TSP-13 Analysis of the Formation of Iron Oxides on Surfaces by Diffuse Reflectance Spectroscopy Technique
Catalina Melo Piraquive, OscarEdwin Piamba Tulcan (National University of Colombia, Colombia)
The characterization of corrosion products on surfaces of materials that are expose to different conditions of operation, demand the development of a technique cheap, fast and portable. This work describes optical technique that have been analysed to study the products of corrosion on surfaces. The Diffuse Reflectance Spectroscopy (DRS) is a novel technique where the analysis of spectra has proved useful to identify and characterize different types of oxides. The analysis of the spectrum within the visible and near-infrared (Vis/NIR, 400-2500nm) regions were studied to assess the presence of these oxides and identify it. The spectral data were transformed and then analyzed. The results indicate that the DRS technique allow to predict the relationship between spectrum and different oxides present on surfaces.
TSP-15 Plasma Electrolytic Oxidation Process Diagnostics Using Microdischarge Video Imaging
Evgeniy Parfenov, Denis Lazarev, Michail Gorbatkov (Ufa State Aviation Technical University, Russian Federation); Aleksey Yerokhin (The University of Sheffield, UK)

Plasma electrolytic oxidation (PEO) is a modern knowledge-based technology for applying protective coatings on surfaces of light metals and their alloys. The PEO process is held at high voltages (400-1000V) which results in the coatings with high wear and corrosion resistance. To design PEO process control system, it is necessary to solve the diagnostics problem for the coating thickness; this is a challenge because a direct measurement of the surface layer properties during the treatment using conventional techniques is infeasible.

In this paper a solution for this problem is proposed based on the analysis of microdischarge video image processing and the process modelling. On the first stage using multifactorial experimental design a set of experimental data regarding the coating thickness, surface roughness and microdischarge images was acquired for DC PEO in the voltage range from 450 to 600V. With a help of a general regression neural network F1 a connection between the output characteristics and the input variables (U, t) was established. An algorithm for microdischarge image processing and assessing the statistical characteristics of their population was developed and implemented into a software. The software allows automatic identification of the microdischarge location and size, as well as calculation of statistical characteristics of their population. With the help of neural network F2 a connection between the microdischarge characteristics, inputs (U, t) and image exposure was formalized. It was shown that for the surface state diagnostics it is enough to use histogram characteristics: microdischarge population density and average size of micro-discharges.

According to the analysis of change in the characteristics of microdischarge populations, two ways to diagnose the coating thickness during PEO process were developed. The first method is based on the application of an integral information parameter, which does not depend explicitly on the voltage and time, but uses the properties of the microdischarge population. This parameter has a physical meaning of the surface covered by microdischarges, integrated over time. The coating thickness is further calculated from piecewise linear calibration curves. The second method is based on the application of neural network F3 transforming the set of informative parameters of microdischarges into the set of the coating thickness and surface roughness.

It was shown that the developed methods can be used for indirect measurements of the coating thickness during plasma electrolytic oxidation, and applied in the PEO process control system with a new feedback loop considering the surface state parameters.

TSP-16 Transient Calorimetric Plasma Diagnostics Utilizing Passive Probes
Sven Bornholdt, Holger Kersten (Institute of Experimental and Applied Physics, Kiel University, Germany)

We present our recent progress in utilizing calorimetric probes for plasma diagnostic purposes in thin film deposition. The developed technique - called the transient method – allows for a faster calibration of the probe and energy flux measurements as well as for simultaneous and more precise determination of plasma parameters like plasma and floating potential and plasma density [1].

By combining the conventional method of passive calorimetric probes [2] with the well-established electrostatic probe, it is now possible to build a model of the energy influx and its contributions by electrons, ions, recombination and other surface processes.

The presentation includes the basic principle of calorimetric measurements as it was already used by J.A. Thornton in the 1970’s [3]. By addressing the drawbacks of the conventional method, we developed a method to shorten the time needed for the calibration process, which is necessary for a quantitative determination of the total energy influx from plasmas towards a surface. By using this procedure in a capacitively coupled RF plasma using Argon as process gas we demonstrate the applicability in a plasma environment. Argon was chosen in order to keep the number of different contribution to the integral energy influx small. However, the method can also be used in more complex situations, e.g. magnetron sputtering. In this case contributions from the neutral sputtered particles as well as the film formation itself have to be included.

Plasma parameters are determined from the electrical currents as it is typical for electrostatic probes. By using the same probe for current end energy flux measurements we avoid discrepancies caused by different geometries and conditions. Using the currents and the plasma parameters, one can calculate the various contributions caused by the different species and surface processes easily. Comparing the sum of all calculated contributions with the energy influx determined from the temperature curve obtained during the probe voltage sweep allows for verification of the model.

[1] S. Bornholdt and H. Kersten, Eur. Phys. J. D. 67(8):167 (2013)

[2] S. Bornholdt et al, Surf. Coat. Tech. 205:388-392 (2011)

[3] J.A. Thornton, Thin Solid Films, 54:23-31 (1978)
TSP-17 Tensile Creep Rate Analysis of a Dental Feldspathic Porcelain Veneer
Alexander Lunt (University of Oxford, UK); Saurabh Kabra, Joe Kelleher, Shu Yan Zhang (ISIS, Science and Technology Facilities Council, UK); Alexander Korsunsky (University of Oxford, UK)

In dental prostheses, metallic alloy and all ceramic copings, e.g. of Yttria Partially Stabilised Zirconia (YPSZ) are coated with feldspathic porcelain veneers to deliver an aesthetically pleasing finish and to produce a surface of similar hardness to human teeth. A prominent failure mode of such coatings is associated with the chipping of the near-interface porcelain. Studies into failure at the porcelain-YPSZ interface have revealed that there is a complex interplay between tempering, phase transformation and coefficient of thermal expansion mismatch at this location. Recent Transmission Electron Microscopy has also provided evidence that the interaction between tensile stresses and high temperatures at the interface region are sufficient to induce creep in the porcelain coating at sub-micron length scales. Several previous studies have focused on the bending and compression creep rate behaviour in silica-alumina ceramics. These fail to account directly for the importance of pure tensile loading that is likely to induce micro-cavitation and promote fracture. We report the development of a new experimental technique capable of loading a specially designed tensile creep specimen. Tensile creep rate analysis was performed on porcelain samples made from Cerec Mark II Vitablocs over a range of temperatures (between 650°C and 800°C) and stresses (50MPa to 125MPa) that are similar to the conditions that arise during veneer sintering. The steady state power law creep rate equation was found to be representative of the strain behaviour observed. The activation energy was evaluated to be equal to 243.4 ± 3.3 kJmol-1 and the stress exponent ranged from 1.24 to 1.52 across the range of temperatures. This variation may be an indicative of varying stress sensitivity at different thermal energy levels. The results provide an important quantified basis for numerical modelling of the temperature dependent stress evolution in porcelain veneers due to creep.

TSP-18 Cross-sectional Analysis of AlCr Composite Cathodes after Erosion in Cathodic Arc Plasma with Inert and Reactive Gas Atmosphere
Robert Franz, Francisca Mendez-Martin (Montanuniversität Leoben, Austria); Peter Polcik (Plansee Composite Materials GmbH, Germany)

Hard and wear-resistant coatings based on the system aluminium and chromium represent the state of the art in the protection of tools used in metal cutting operations. Using physical vapour deposition techniques, nitrogen and/or oxygen can be added to the plasma to synthesise nitrides, oxides or oxynitrides. A frequently employed method is cathodic arc deposition which is characterised by a high degree of ionisation, enabling an optimisation of the growth condition. In addition high deposition rates can be achieved which reduces the process time and, hence, the production costs. Multi-element cathodes containing both elements are employed to facilitate an easier process control and reproducibility. However, the plasma conditions in the cathodic arc plasma using multi-element cathodes and the erosion behaviour of theses cathodes in the different gaseous atmospheres are scarcely studied.

In the present investigation, AlCr composite cathodes with composition of 75/25, 50/50 and 25/75 at.% were exposed to a cathodic arc plasma in Ar, N2 and O2 atmosphere. Due to periodic heating and cooling of the cathode’s near-surface region in the cathode spots, an intermixing of the elements Al and Cr occurred and was analysed by cross-sectional analysis using focused ion beam and scanning electron microscopy. Recording the spatial distribution of the elements revealed regions of virgin Cr grains embedded in the Al matrix as well as regions of partial or complete intermixing of both elements. Due to exposure of the cathode surface to nitrogen or oxygen atoms or molecules, nitride and oxide phases were noticed which is typically referred to as cathode poisoning. The results regarding the cathode erosion are put in context with recently reported ion charge state distributions and ion energy distribution functions obtained with the same AlCr cathodes and gas atmospheres [1, 2].

References:

[1] R. Franz, P. Polcik, A. Anders; IEEE Trans. Plasma Sci. 41 (2013) 1929–1937

[2] R. Franz, P. Polcik, A. Anders; Surf. Coat. Technol. (2015) under review, arXiv:1412.5772

TSP-19 Two-dimensional Material for Perovskite Solar Cells
Mulong Yang, Kung Po-Kai, Jyh-Ming Ting, Kai-Chun Huang (National Cheng Kung University, Taiwan)
Hybrid organic/inorganic perovskite for use as a light absorber in solar cell has attracted recently great attentions in photovoltaic research. In this article, a novel two-dimensional material serving as a charge transport layer was used in lead iodide (CH3NH3PbI3) perovskite solar cell. This thin layer was synthesized and deposited on the perovskite layer by various processes. The perovskite layer was also deposited on the substrate using different methods. X-ray diffractometry, scanning electron microscopy, energy dispersive spectrometry, and UV-visible spectroscopy were used to characterize the materials. The resulting solar cells were evaluated using a sun light simulator, current-voltage measurement, incident photon-to-electron conversion efficiency, intensity modulated photocurrent/photovoltage spectroscopy, and electrochemical impedance spectroscopy. The effects of material properties on the cell performance are addressed.
Time Period ThP Sessions | Topic TS Sessions | Time Periods | Topics | ICMCTF2015 Schedule