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Paper-based PbS photodetector sensitive in the visible spectrum is reported. Nanocrystalline PbS-on-paper devices are fabricated by a spin coating method on white paper (300 GSM) from a methanolic precursor solution. Photodetector cells of gap 0.2 cm and length 0.5 cm are prepared by drawing contacts by monolithic cretacolor 8B pencil. X-ray diffractometer confirmed the deposition of nanocrystalline PbS films with 14 nm crystallites. The SEM illustrated the uniform coating of nanocrystalline PbS thin films on cellulose fibres of papers having an average thickness of fibres are 10 µm. The linear J-V characteristics in dark and under illumination of light using graphite trace on nanocrystalline PbS-on-paper shows good ohmic contact. The resistivity of pencil trace is 30 Ω·cm. Spectral response measurements of photodetector reveal the excellent sensitivity from 400 to 700 nm with a peak at 550 nm. The best responsivity anddetectivity are 0.7 A/W and 1.4 × 1012 Jones respectively. These paper-based low-cost photodetectors devices have fast photoresponse and recovery without baseline deviation.

Here, we presented a novel, cost effective approach to fabricate flexible piezoelectric nanogenerator (NG) consisting of ZnS nanowires (NWs) grown upon cellulose. An output voltage of 4 V is generated from the nanocomposite paper (NC-paper) based NG. Subsequently, it has the capability to power Light Emitting Diode (LED) and charging up capacitor. The corresponding energy stored in the capacitor (1 µF) is 16 µJ. Thus, the fabricated NC-paper based NG can be used for smart textile structures, wearable and self-powered nanodevices.

The commercial telecommunication system in future would explore the electromagnetic spectrum with higher frequency than used now, because it requires higher speed of transmission data. Using the millimeter waves (mmW) with frequency ranging from 30 to 300 GHz, such requirement could be fulfilled. The upcoming 5G cellular technology is expected to use frequency 30 GHz or higher. Then materials with a specific characteristic at the mmW range are interesting to be explored and investigated. Here, we report the synthesis process of graphene/TiO2 deposited on paper and their transmission characteristics to the electromagnetic energy at frequency 27-40 GHz (Ka-Band). The reduced graphene oxide (rGO) was synthesized by a modified Hummers method with introduction of microwave irradiation in the process. rGO and TiO2 were mixed in ethanol solution and deposited on the paper by a spraying technique. Transmission coefficient of electromagnetic wave energy at Ka-Band was measured by using the millimeter vector networ...

CdSe quantum dot has great potential in various applications especially for emitting devices. One example potential application of CdSe quantum dot is security label for anti-counterfeiting. In this work, we present a practical approach of security label on paper using one and two colors of colloidal CdSe quantum dot, which is used as stamping ink on various types of paper. Under ambient condition, quantum dot is almost invisible. The quantum dot security label can be revealed by detecting emission of quantum dot using photoluminescence and cnc machine. The recorded quantum dot emission intensity is then analyzed using home-made program to reveal quantum dot pattern stamp having the word ’RAHASIA’. We found that security label using quantum dot works well on several types of paper. The quantum dot patterns can survive several days and further treatment is required to protect the quantum dot. Oxidation of quantum dot that occurred during this experiment reduced the emission intensity of quantum dot patterns.

We successfully developed a method utilizing colloidal CdSe nanocrystalline quantum dot for anti-counterfeiting label on a piece of glossy paper. We deposited numbers and lines patterns of toluene soluble CdSe quantum dot using rubber stamper on a glossy paper. The width of line pattern was about 1-2 mm with 1-2 mm separation between lines. It required less than one minute for deposited CdSe quantum dot on glossy paper to dry and become invisible by naked eyes. However, patterned quantum dot become visible using long-pass filter glasses upon excitation of UV lamp or blue laser. We characterized photoluminescence of line patterns of quantum dot, and we found that emission boundaries of line patterns were clearly observed. The error of line size and shape were mainly due to defect of the original stamper. The emission peak wavelength of CdSe quantum dot was 629 nm. The emission spectrum of deposited quantum dot has full width at half maximum (FWHM) of 30-40 nm. The spectra similarity between deposited quant...

Thin films of graphene oxide (or reduced graphene oxide) recently drawn a huge attention because of their several applications which are based on properties of graphene. The aim of the present paper is twofold: to find the straightforward, simple and cheap method for the preparation of thin film of graphene oxide and to study the effect of electron beam irradiation on the GO thin film. GO film was made by drop casting method from commercially procured aqueous solution of GO (concentration - 5 g/L). Electron beam irradiation were done in SEM obtain from MIRA II LMH from TESCAN. Irradiation of GO film was done at 25 keV electron beam energy. The authors have measured I-V characteristic of pristine as well as irradiated GO thin film in two probe configuration. Irradiation time were chosen 1 min, 33 min and 100 min which corresponds to 3×1011 e-/cm2, 1×1013 e-/cm2 and 3×1013 e-/cm2 fluence of electron beam. The samples were characterized using SEM and Raman methods. I-V spectra show that the resistance of fil...

In this paper we have shown enhanced supercapacitive property of electrochemically reduced graphene oxide (ERGO) and manganese dioxide (MnO2) based heterostructure over single MnO2 thin film grown by electrochemical deposition on indium tin oxide (ITO). ERGO improves the electrical conduction leading to decrease of the internal resistance of the heterostructure.

Using plane wave pseudo potential density functional theory, we studied the electronic properties of graphene with different C:O ratio. In this work, we discussed the changes that occur in electronic band structure of graphene functionalized with different amount of epoxy group. Electronic band gap depends on C:O ratio in graphene oxide containing epoxy group. The present work will have its implication for making devices with tunable electronic properties by oxidizing graphene.

Here, we report electronic properties of graphene field-effect transistor in a magnetic field of 9.0 tesla. Raman spectroscopy on graphene sample prepared by anodic bonding method shows it to be of the highest quality. The observation of charge neutrality point at a positive gate voltage is due to hole doping in the sample from the immobile oxygen ions created during anodic bonding process. Hysteresis observed in the longitudinal resistance (between source and drain) while sweeping voltage at gate in a loop may be due to high viscosity of polythene oxide matrix for mobile Li ions. The longitudinal resistance as a function of gate voltage Vg shows that both kind of charge carriers (electron and hole) can be doped in graphene, which is further ascertained by the Hall measurements.

Few layer graphene (FLG) had been successfully grown on polycrystalline Ni films or foils on a large scale using DC Plasma Enhanced Chemical Vapor Deposition (DC PE‐CVD) as a result of the Raman spectra drawn out of the sample. The size of graphene films is dependent on the area of the Ni film as well as the DC PE‐CVD chamber size. Synthesis time has an effect on the quality of graphene produced. However, further analysis and experiments must be pursued to further identify the optimum settings and conditions of producing better quality graphene. Applied plasma voltage on the other hand, had an influence on the minimization of defects in the graphene grown. It has also presented a method of producing a free standing PMMA/graphene membrane on a FeCl3(aq) solution which could then be transferred to a desired substrate.

The micromechanically exfoliated monolayer graphene on SiO2, Al2O3, and HfO2 are investigated by Raman spectroscopy and AFM measurement. The pristine graphene seems to have stronger adhesion and higher carrier concentration when the dielectric constant of the underlying oxide is higher. It is found that high vacuum annealing significantly increases the interaction between graphene and the oxides and Raman G and 2D bands shift to higher wavelength. The high vacuum annealing for graphene on HfO2 increases carrier concentration of up to ∼10 times with a corresponding Fermi level shift of ∼0.65 eV although that of graphene on SiO2 induces a biaxial compressive stress as high as 4 GPa on graphene. As the three dielectrics evaluated in this work are the most commonly used gate dielectrics in field‐effect transistors, these findings will be useful in fabrication of graphene based field‐effect transistors.

Using the pulsed deposition technique, the growth of GaN on graphite substrate is possible. Because of the two‐dimensionality of graphite, the strain for the lattice mismatch due to the growth of GaN is absorbed by the topmost layer of graphite. We confirm that the electronic and the atomic structure for the interface of the grown GaN on graphite is almost similar to the interface of GaN on a single graphene layer using the density functional theory.

This paper presents a short review on terahertz imaging systems based on several types of technology used in the terahertz detection schemes. Some commercial products from ThruVision Systems Limited Company have utilized GaAs Schottky diode detector at 0.25 THz to produce passive terahertz images for public and homeland security. On the other hand, TeraSense Group Incorporated Company has developed and invented a ground-breaking technology which employs sensor consisting of a matrix of plasmonic semiconductor detectors in their latest products to generate terahertz images in the 0.1 – 1.0 THz frequency range. Recently, the utilization of two-terminal unipolar nanodiodes, known as the self-switching diodes (SSDs), as terahertz detectors has shown promising results. The planar structure of SSD not only enables the device to operate at high frequencies due to low intrinsic parasitic capacitance, but also allows the realization of the device using only a single lithography step. This makes the fabrication process of SSDs faster, more simple, and at lower cost when compared to other electronic devices such as Schottky diodes. The development and recent achievement of SSDs as terahertz detectors are also presented in this paper.

This paper presents the fabrication of Interdigitated Electrodes (IDEs) towards the detection of glucose. The transducer is constructed based on IDE because of its single layer electrode structure. Majority of IDE used metal such as gold and nickel as the electrodes because of their excellent electrical performances. However, in this paper, aluminium is applied as metal of electrodes not only because of its stable material but also trying to investigate the interaction between aluminium metal and Titanium dioxide, TiO2 with glucose detection. Titanium dioxide has been utilized as thin film on the deposited aluminium electrodes to increase the interaction between aluminium electrodes with different concentration of glucose solution. The designs of IDEs interdigitated array (IDBA) and interdigitated ring array (IDRA) are performed by using AUTOCAD and it is printed on a transparency paper as a mask. Customary photolithography methods with positive resist are applied to transfer the pattern on a silicon wafer in this fabrication process. Then, the fabricated IDEs are viewed and examined under Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) to verify the surface morphology and topology. The electrochemical performance of IDEs is observed through cyclic voltammogram characteristics performed using potentiostat. In the nut shell, both IDBA and IDRA are tested within 0 to 100 mM range of glucose concentration.

In the present paper, we have simulated the high performing SnS based solar cell by using SCAPS. SCAPS is one dimensional simulating software which is used for the simulation of solar cell. The solar cell consists of SnS based absorber layer, Zn (O, S): N buffer layer and ZnS as window layer. The p-SnS/Zn (O, S): N/ZnS is device structure of solar cell. The effect of absorber layer thickness and temperature on electrical parameter of solar cell have been reported in the present paper.

The presence of lead material in lead halide perovskite absorber is always remains a major obstacle due to its toxic nature. The emergence of tin halide perovskite absorber will overcome this toxicity issue and due to its extraordinary properties such as direct band gap and compatible visible spectrum of solar cells attracts a wide attention to researchers to focus on the development of lead free perovskite solar cells. This paper comprises of the device simulation of lead-free perovskite material. In addition, effect of various hole transport layers, and the effect of absorber band gap have been studied. It has been observed from the results that along with the proper band alignment of HTM layer with perovskite layer, the mobility of HTM layer plays an important role to achieve better device performance. Furthermore, it has been concluded that Cu2O layer as a hole transport material exhibits better device performance as compare to the other HTM layer used in this paper.

This paper presents the structural and optoelectronic behavior of ZnSiP2 compound theoretically. The calculations are performed using full potential linearized augmented plane wave method (FP-LAPW) within density functional theory (DFT) as embodied in WIEN2K code. For the accuracy of calculation, Perdew-Burke generalized gradient approximation (PBE-GGA) is used. Based on the energy bands, the forbidden band gap of ZnSiP2 was found to be 1.37 eV which is suitable for photovoltaic applications. The formation of bands are explained with the help of spectra of density of states (DOS) to determine the effect of Ge doping at Si site on the electronic structure. We have also performed the computations for ZnSi0.875Ge0.125P2. Energy dependent absorption spectra is also reported in this paper to highlight the possible utilization of these compounds in optoelectronic devices.

An imaging system operated at millimeter (MM) waves and terahertz (THz) frequencies can be used in many applications such as safety monitoring, public security, medical, healthcare and manufacturing. Typically, these systems utilize rectifying antenna (rectenna) to convert electromagnetic radiation into usable DC power which will be used to generate images. One of the main components of rectenna is the rectifier. Hence, this paper explores the current review on several semiconductor rectifiers that have been significantly deployed for MM-wave/THz imaging systems. This includes Schottky diodes, metal-insulator-metal (MIM) diodes, self-switching diodes (SSDs) and ballistic rectifiers (BRs). The rectifying performance of these devices are discussed in terms of their voltage responsivity and noise-equivalent power (NEP). The standard fabrication process of each device is also presented in this paper as well as their recent development and achievement as high-frequency rectifiers for MM-wave/THz imaging systems.

Printhead with microscale nozzle is very important for electrohydrodynamic jet (E-jet) printing, that decides output performance of system. It is challenge and necessary to design and fabricate a protruding Si-based nozzle strucure for E-jet prining. In this paper, a protruding Si-based nozzle structure is designed and the corresponding fabricating flow chart is introduced based on photolithography, wet etching, magnetron sputtering, inductively coupled plasma. Then, the effect of etching ratio between big area and small section is analyzed and discussed in details. The failure in first time fabrication shows that it is indipensable to not only achieve the process parameters, but also design a set of reasonable fabricating flow chart for manufacturing a Si-baesd nozzle structure sucessfully. Finally, a protruding Si-based nozzle structue is successfully fabricated for E-jet printing.Printhead with microscale nozzle is very important for electrohydrodynamic jet (E-jet) printing, that decides output performance of system. It is challenge and necessary to design and fabricate a protruding Si-based nozzle strucure for E-jet prining. In this paper, a protruding Si-based nozzle structure is designed and the corresponding fabricating flow chart is introduced based on photolithography, wet etching, magnetron sputtering, inductively coupled plasma. Then, the effect of etching ratio between big area and small section is analyzed and discussed in details. The failure in first time fabrication shows that it is indipensable to not only achieve the process parameters, but also design a set of reasonable fabricating flow chart for manufacturing a Si-baesd nozzle structure sucessfully. Finally, a protruding Si-based nozzle structue is successfully fabricated for E-jet printing.

This paper investigates the reduction of the parasitic absorption in solar cells with poly-silicon based passivating contacts. We analyze the transparency of poly-Si films fabricated at various deposition temperatures. We observe different surface morphologies by scanning electron microscopy and model their spectroscopic ellipsometry reflection data. Based on the measured optical parameters (n and k) we perform ray tracing simulations for quantifying the expected increase of short-circuit current density of a cell. Our study shows that the poly-Si deposition at 530 °C leads to an increase of the photo-generated current density by up to 0.76 mA/cm² when compared to poly-Si films deposited at 610 °C.This paper investigates the reduction of the parasitic absorption in solar cells with poly-silicon based passivating contacts. We analyze the transparency of poly-Si films fabricated at various deposition temperatures. We observe different surface morphologies by scanning electron microscopy and model their spectroscopic ellipsometry reflection data. Based on the measured optical parameters (n and k) we perform ray tracing simulations for quantifying the expected increase of short-circuit current density of a cell. Our study shows that the poly-Si deposition at 530 °C leads to an increase of the photo-generated current density by up to 0.76 mA/cm² when compared to poly-Si films deposited at 610 °C.

This paper uses optical whispering galley modes (WGM) cavities to construct a new electrical sensing interface between prosthetic limb and the brain. The sensing element will detect the action potential signal in the neural membrane and the prosthetic limb will be actuated accordingly. The element is a WGM dielectric polymeric cavity. WGM based optical cavities can achieve very high values of sensitivity and quality factor; thus, any minute perturbations in the morphology of the cavity can be captured and measured. The action potential signal will produce an applied external electric field on the dielectric cavity causing it to deform due to the electrostriction effect. The resulting deformation will cause WGM shifts in the transmission spectrum of the cavity. Thus, the action potential or the applied electric field can be measured using these shifts. In this paper the action potential signal will be simulated through the use of a function generator and two metal electrodes. The sensing element will be si...

This paper is concerned with analyzing the role of polymer swelling induced surface stress in MEMS chemical sensors. The objective is to determine the impact of surface stress on the chemical discrimination ability of MEMS resonator sensors. We considered a case study of hypoxia detection by MEMS sensor array and performed several types of simulation experiments for detection of oxidative stress volatile organic markers in human breath. Both types of sensor response models that account for the surface stress effect and that did not were considered for the analyses in comparison. It is found that the surface stress (hence the polymer swelling) provides better chemical discrimination ability to polymer coated MEMS sensors.This paper is concerned with analyzing the role of polymer swelling induced surface stress in MEMS chemical sensors. The objective is to determine the impact of surface stress on the chemical discrimination ability of MEMS resonator sensors. We considered a case study of hypoxia detection by MEMS sensor array and performed several types of simulation experiments for detection of oxidative stress volatile organic markers in human breath. Both types of sensor response models that account for the surface stress effect and that did not were considered for the analyses in comparison. It is found that the surface stress (hence the polymer swelling) provides better chemical discrimination ability to polymer coated MEMS sensors.

A next generation heavy ion accelerator complex HIAF (High Intensity heavy ion Accelerator Facility) was proposed by IMP and officially approved for nuclear physics and high energy density physics research. HIAF requests ion source that is able to deliver 50 pμA of 238U35+ pulsed beam and 25 pμA of 238U35+ CW beam for injector of a superconducting heavy ion linac. In order to meet the beam intensity requirements of highly charged heavy ions, a 45 GHz superconducting ECR ion source FECR (a Fourth generation ECR ion source) is under intense R&D at IMP. The effective power absorption form the microwaves to the plasma is key issue for increasing the beam intensity. Therefore, we introduced a 45 GHz gyrotron system which is capable for providing output power up to 20 kW in both CW and pulse modes as a microwave power source for FECR. Other than the gyrotron oscillator, the microwave power transmission coupling and ECR heating are critical issues for FECR. Since the wavelength of 45 GHz microwave is about 6.67 mm and the maximum power level is 20 kW, the quasi-optical transmission scheme is utilized for high power transmission. The technical details of transmission line and coupling system will be presented in this paper. After off-line tests of microwave transmission efficiency and mode purity, 45 GHz gyrotron microwave source will be commissioned with SECRAL II (a superconducting ECR ion source optimized for 28 GHz operation), and some preliminary results of ECR heating and intense beam production will be discussed in this paper.

This paper focuses on the impact towards the performance of silicon nanowire field-effect transistor (SiNW-FET) for biosensing application based on different channel lengths of the nanowire. A device numerical modelling tool, Silvaco ATLAS was used to design three p-type SiNW-FET biosensors with different lengths of 0.5, 1.0, and 10.0 μm. The designed devices were simulated in order to observe and compare the effect of different channel length towards the electrical characteristic of the devices. Increase of the nanowire channel length had caused reduction of drain current, ID flowed through the channel from drain to source region. This is related to the increase of electrical resistance, R of the nanowire with the increase of nanowire length, L. In a way to study the effect of different channel lengths on the performance of the SiNW-FET biosensor, several negatively interface charge densities, QF (i.e. −0.1×1012, −0.5×1012, and −1×l012 cm−2) were introduced on the surface of the SiNW channel to represent as the actual target deoxyribonucleic acid (DNA) captured by the bioreceptor of the biosensor. Based on the results, these negatively QF attracted the hole carriers below the surface of p-type nanowire to form an accumulation of charge carriers in the channel, causing an increase in the device output ID. Increase of the applied negative charge density had allowed for more ID to flow across the channel between drain and source region. The changes of ID with the applied QF are utilized to determine the sensitivities and limit of detections (LOD) for all designed biosensor with different channel lengths. In comparison, the smallest nanowire length of 0.5 μm produced the highest sensitivity and lowest LOD of 2.17 μA/cm−2 and 7.85×1010 cm−2, respectively, hence demonstrates better performance of SiNW-FET biosensor for the detection of specific charged DNA in analyte.This paper focuses on the impact towards the performance of silicon nanowire field-effect transistor (SiNW-FET) for biosensing application based on different channel lengths of the nanowire. A device numerical modelling tool, Silvaco ATLAS was used to design three p-type SiNW-FET biosensors with different lengths of 0.5, 1.0, and 10.0 μm. The designed devices were simulated in order to observe and compare the effect of different channel length towards the electrical characteristic of the devices. Increase of the nanowire channel length had caused reduction of drain current, ID flowed through the channel from drain to source region. This is related to the increase of electrical resistance, R of the nanowire with the increase of nanowire length, L. In a way to study the effect of different channel lengths on the performance of the SiNW-FET biosensor, several negatively interface charge densities, QF (i.e. −0.1×1012, −0.5×1012, and −1×l012 cm−2) were introduced on the surface of the SiNW channel to represent...

Group II-VI Compounds have emerged out as most suitable in the class of photo sensitive material. They represent a strong position in terms of their applications in the field of detectors as well as photo voltaic devices. Cadmium telluride is the prime member of this Group, because of high acceptance of this material as active component in opto-electronic devices. In this paper we report preparation and characterization of CdTe thin films by using a most economical screen printing technique in association with sintering at 510°C temperature. Surface morphology and smoothness are prime parameters of any deposited to be used as an active region of devices. Thus, we studied of the screen printed thin film by means of atomic force microscopy (AFM) and scanning electron microscopy (SEM) for this purpose. However, growth processes induced intrinsic defects in fabricated films work as charge traps and affect the conduction process significantly. So the conduction mechanism of deposited CdTe thin film is studied under dark as well as illuminated conditions. It is found that the deposited films showed the space charge limited conduction (SCLC) mechanism and hence various parameters of space charge limited conduction (SCLC) of CdTe film were evaluated and discussed and the photo responsive resistance is also presented in this paper.

This paper demonstrates a Junction-less Double Gate n-p-n Impact ionization MOS transistor (JLDG n-IMOS) on a very light doped p-type silicon body. Device structure proposed in the paper is based on charge plasma concept. There is no metallurgical junctions in the proposed device and does not need any impurity doping to create the drain and source regions. Due to doping-less nature, the fabrication process is simple for JLDG n-IMOS. The double gate engineering in proposed device leads to reduction in avalanche breakdown via impact ionization, generating large number of carriers in drain-body junction, resulting high ION current, small IOFF current and great improvement in ION/IOFF ratio. The simulation and examination of the proposed device have been performed on ATLAS device simulatorsoftware.This paper demonstrates a Junction-less Double Gate n-p-n Impact ionization MOS transistor (JLDG n-IMOS) on a very light doped p-type silicon body. Device structure proposed in the paper is based on charge plasma concept. There is no metallurgical junctions in the proposed device and does not need any impurity doping to create the drain and source regions. Due to doping-less nature, the fabrication process is simple for JLDG n-IMOS. The double gate engineering in proposed device leads to reduction in avalanche breakdown via impact ionization, generating large number of carriers in drain-body junction, resulting high ION current, small IOFF current and great improvement in ION/IOFF ratio. The simulation and examination of the proposed device have been performed on ATLAS device simulatorsoftware.

The near infra-red CuInSeS/ZnS core/shell quantum dots have been investigated toward luminescent solar concentration applications. This quantum dots possess advantages of Stocks shift as large as more than 0.43eV and high photoluminescence quantum yield of 70%. The paper presents the effect of large stock shift CuInSeS/ZnS quantum dots on reducing the reabsorption losses in Luminescent solar concentrators by using experimental investigation. The Luminescent solar concentrators sheet was fabricated in dimension of 40 mm × 30 mm × 3mm by dispersing 0.03 % wt. CuInSeS/ZnS quantum dots particles in a polymethylmethacrylate waveguide and their optical properties (absorptions/emissions) were characterized. Results are showing that the CuInSeS/ZnS quantum dots - Luminescent solar concentrators provides a promising way for the reduction of reabsorption losses in Luminescent solar concentrators.The near infra-red CuInSeS/ZnS core/shell quantum dots have been investigated toward luminescent solar concentration applications. This quantum dots possess advantages of Stocks shift as large as more than 0.43eV and high photoluminescence quantum yield of 70%. The paper presents the effect of large stock shift CuInSeS/ZnS quantum dots on reducing the reabsorption losses in Luminescent solar concentrators by using experimental investigation. The Luminescent solar concentrators sheet was fabricated in dimension of 40 mm × 30 mm × 3mm by dispersing 0.03 % wt. CuInSeS/ZnS quantum dots particles in a polymethylmethacrylate waveguide and their optical properties (absorptions/emissions) were characterized. Results are showing that the CuInSeS/ZnS quantum dots - Luminescent solar concentrators provides a promising way for the reduction of reabsorption losses in Luminescent solar concentrators.

In this paper, the photonic band gap structure in the visible and near infrared for a ternary metal dielectric photonic crystal has been theoretically investigated. At the normal incidence, the high reflectance range can be significantly enlarged at a thicker metal film. The transmission of the structure containing Cu has large compared to the other metals like Al and Ag metals. The transmission properties of the metal are dependent upon the value of the plasma frequency. In this paper we consider the effect of the variation of the thickness of the metal on the reflection bands of ternary metallic-dielectric photonic crystal (MDPC). Finally we find that the enlargement of band gap in MDPC is due to the addition of increase of the thickness of metallic film at normal incidence. All the theoretical calculations are made based on the transfer matrix method together with the Drude model of metal.In this paper, the photonic band gap structure in the visible and near infrared for a ternary metal dielectric photonic crystal has been theoretically investigated. At the normal incidence, the high reflectance range can be significantly enlarged at a thicker metal film. The transmission of the structure containing Cu has large compared to the other metals like Al and Ag metals. The transmission properties of the metal are dependent upon the value of the plasma frequency. In this paper we consider the effect of the variation of the thickness of the metal on the reflection bands of ternary metallic-dielectric photonic crystal (MDPC). Finally we find that the enlargement of band gap in MDPC is due to the addition of increase of the thickness of metallic film at normal incidence. All the theoretical calculations are made based on the transfer matrix method together with the Drude model of metal.

In this paper, simulation of double loop mirrors multi-wavelength Brillouin fiber laser utilizing semiconductor optical amplifier based on single mode fiber as gain medium was demonstrated. In optical communications, the fiber laser with nonlinear optical loop mirror multi-wavelength Brillouin fiber laser is expected to play a key role in optical signal processing applications. This paper presents the use of double loop in order to produce a stable multi -wavelength comb signals. This fiber laser configuration was integrated a semiconductor optical amplifier with 0.8A of injected current and polarization controller in both loop mirror placed after a 6km of single mode fiber, a tunable laser sources with different of injected Brillouin pump power from -12 dBm up to 12 dBm are demonstrated. From the results, by using -1 dBm of BP input power, 7 output signals at 1550 nm can be obtained with average optical signal to noise ratio at 22 dB.

Interdigitated electrodes (IDEs) are made of two individually addressable interdigitated comb-like electrode structures. IDEs are one of the most favored transducers, widely utilized in technological applications especially in the field of biological and chemical sensors due to their inexpensive, ease of fabrication process and high sensitivity. In order to detect and analyze a biochemical molecule or analyte, the impedance and capacitance signal need to be obtained. This paper investigates the working principle and influencer of the impedance and capacitance biosensors. The impedance biosensor depends on the resistance and capacitance while the capacitance biosensor influenced by the dielectric permittivity. However, the geometry and structures of the interdigitated electrodes affect both impedance and capacitance biosensor. The details have been discussed in this paper.

In LED-based visible light communication, the choice of light source device is an important issue. In this paper, the frequency response (FR) of different types of blue LEDs and phosphors is measured. On the basis of that, this paper proposes the FR model of phosphor and supplements the FR model of blue LED. And also, a method is proposed to calculate the FR of phosphor coated LEDs using FR of blue LED and that of phosphor. On this basis, this paper analyses the influencing factors of the FR of blue LED and FR of phosphor respectively. It provides guidance for not only selecting the light source device but also selecting and blending phosphor in visible light communication based on LED.

In this paper we present construction and analysis of nuclear micro battery driven by Strontium 90 (Sr-90). Our design based on charge deposition on the plates of a capacitor and polarization of dielectric materials between the plates. In the construction we have used liquid Sr-90 with activity 100 mCi in cylindrical ampoule coiled up by thin film graphene as one plate and Manganase dioxide (MnO2) as other plate of the capacitor. A dielectric material (paper) is inserted between the plates. The high energetic beta particles from the Sr-90 penetrate graphene to produce ionization and then electrons are removed from graphene to dielectric material. Electrons inside the dielectric material cause polarization of dipoles. Consequently the radiation from the isotope produces an external current. We discuss effect of beta particles on dielectrics and electrodes beside advantage and disadvantage of a battery of this type.

The paper presents the results of development and investigation of film panoramic pressure sensors on the base of the oxygen sensitive porphyrin platinum complex, photo-curable polymer, and nematic liquid crystals. Pressure sensitive films are formed by two methods: photo-polymerization of the initial composition under the action of the laser radiation of the uniform intensity, and reflective holography method. Spectral and dynamic characteristics of the films are given. The effect of the film structure, initial composition content, and formation technology on the dependence of the film luminescence intensity on the pressure is considered.The paper presents the results of development and investigation of film panoramic pressure sensors on the base of the oxygen sensitive porphyrin platinum complex, photo-curable polymer, and nematic liquid crystals. Pressure sensitive films are formed by two methods: photo-polymerization of the initial composition under the action of the laser radiation of the uniform intensity, and reflective holography method. Spectral and dynamic characteristics of the films are given. The effect of the film structure, initial composition content, and formation technology on the dependence of the film luminescence intensity on the pressure is considered.

This paper presents the simple fabrication of interdigital capacitor (IDC) using print circuit board (PCB) for glucose biosensor. PCB type FR04 laminated with Cu as electrode was used as sensor base. The IDC pattern of sensor was designed by computer aided design program and printed with a laser printer on plastic polymers. Then, the IDC pattern was transferred into PCB by a laminating machine. The etching process of PCB was done by immersing in ferric chloride liquid to form Cu pattern. There were five patterns of sensors including 5, 10, 15, 20 and 25 patterns. The capacitance value of PCB was measured with RCL meter when IDC biosensor was put in air, aquades, and glucose liquid with various moles of glucose (0.02, 0.04, 0.06, 0.08, 0.1M). In air medium, the increase of pattern number of IDC sensor (from 5 to 25) caused the sensor capacitance rose from 22 pf to 46 pf. In addition, the capacitance of sensor was dramatically increased until 0.36 µf while IDC sensor with 25 patterns was put in aquades medium. In liquid glucose medium, the capacitance of IDC biosensor with 25 patterns increased until 0.58 µf on 0.1 M glucose liquid.This paper presents the simple fabrication of interdigital capacitor (IDC) using print circuit board (PCB) for glucose biosensor. PCB type FR04 laminated with Cu as electrode was used as sensor base. The IDC pattern of sensor was designed by computer aided design program and printed with a laser printer on plastic polymers. Then, the IDC pattern was transferred into PCB by a laminating machine. The etching process of PCB was done by immersing in ferric chloride liquid to form Cu pattern. There were five patterns of sensors including 5, 10, 15, 20 and 25 patterns. The capacitance value of PCB was measured with RCL meter when IDC biosensor was put in air, aquades, and glucose liquid with various moles of glucose (0.02, 0.04, 0.06, 0.08, 0.1M). In air medium, the increase of pattern number of IDC sensor (from 5 to 25) caused the sensor capacitance rose from 22 pf to 46 pf. In addition, the capacitance of sensor was dramatically increased until 0.36 µf while IDC sensor with 25 patterns was put in aquades medi...

This paper presents the miniaturization of the microstrip antenna on ferrimagnetic substrate for operate at a frequency of 2.5 GHz, where the full wave method Transverse Transmission Line-TTL is used it for obtain resonance frequency. For validate this method in these substrates, the results as function of DC magnetic field are shown. When the field is 132.6 AT/m, the value of reference is 151.7 MHz and the value of TTL is 151.3 MHz. The dimensions are obtained for the frequency of 2.5 GHz and a comparison is done with ferrites and conventional substrate, showing a reduction in volume of the antenna of 2808.96 mm3 for 0.39 mm3 when the ferrites are used.This paper presents the miniaturization of the microstrip antenna on ferrimagnetic substrate for operate at a frequency of 2.5 GHz, where the full wave method Transverse Transmission Line-TTL is used it for obtain resonance frequency. For validate this method in these substrates, the results as function of DC magnetic field are shown. When the field is 132.6 AT/m, the value of reference is 151.7 MHz and the value of TTL is 151.3 MHz. The dimensions are obtained for the frequency of 2.5 GHz and a comparison is done with ferrites and conventional substrate, showing a reduction in volume of the antenna of 2808.96 mm3 for 0.39 mm3 when the ferrites are used.

In this paper, we numerically investigate CdTe/CdS PV cell properties using a simulation program Solar Cell Capacitance Simulator in 1D (SCAPS-1D). A simple structure of CdTe PV cell has been optimized to study the effect of temperature, absorber thickness and work function at very low incident power. Objective of this research paper is to build an efficient and cost effective solar cell for portable electronic devices such as portable computers and cell phones that work at low incident power because most of such devices work at diffused and reflected sunlight. In this report, we simulated a simple CdTe PV cell at very low incident power, which gives good efficiency.

In this paper we report our experimental results from the preparation of large-scale sub-modules polymer solar cells, which comprise of a series-interconnected of three single cells on a flexible substrate. The cells have the structure of PET/ITO/PEDOT:PSS/MDMOPPV:nc-ZnO/Ag/PET. The sub-modules are prepared using two different geometries of cells, 6 × 1 cm and 3 × 2 cm, respectively, where the active area of these modules is the same. The electrical characteristics of the sub-modules were investigated under Air Mass (AM) 1.5G illumination with light intensity of 600 W/m2. The best electrical characteristic is resulted by sub-module with the cells in dimension of 6 × 1 cm, which yielded an open circuit voltage of 0.65 V, a short circuit current of 0.87 mA, a maximum power of 0.28 mW, and a power conversion efficiency of 0.26%.In this paper we report our experimental results from the preparation of large-scale sub-modules polymer solar cells, which comprise of a series-interconnected of three single cells on a flexible substrate. The cells have the structure of PET/ITO/PEDOT:PSS/MDMOPPV:nc-ZnO/Ag/PET. The sub-modules are prepared using two different geometries of cells, 6 × 1 cm and 3 × 2 cm, respectively, where the active area of these modules is the same. The electrical characteristics of the sub-modules were investigated under Air Mass (AM) 1.5G illumination with light intensity of 600 W/m2. The best electrical characteristic is resulted by sub-module with the cells in dimension of 6 × 1 cm, which yielded an open circuit voltage of 0.65 V, a short circuit current of 0.87 mA, a maximum power of 0.28 mW, and a power conversion efficiency of 0.26%.

FBAR (Thin Film Bulk Acoustic Wave Resonator) devices are commonly used as application of RF (Radio Frequency) filters for the cell phones and other communication devices. This paper reports about the measurement of the efficiency of FBAR devices. The efficiency is commonly measured in terms of the EMCC (Electromechanical coupling coefficient) and QF (Quality factor). Since the FBAR devices are designed in many shapes and sizes which depend on their working frequency range. So every shape and size has a different value of QF and EMCC. This paper compares the various shapes in terms of QF, EMCC and spurious modes of L-Band (1-2 GHz) resonator. Once the best shape is selected, the study of different metal electrode materials coupling with piezoelectric layer and the effect of the thickness ratio (td) of electrode layer and the piezoelectric layer is discussed.

This paper deals with temperature dependent study on material gain of InGaAsP/InP lasing nano-heterostructure with in TE mode. The model is based on simple separate confinement heterostructure (SCH). Material gain for the structure has been simulated for below and above the room temperatures. Different behaviors of the material gain for both ranges of the temperature have been reported in this paper. The results obtained in the simulation of the heterostructures suggest that only the shift in maximum gain takes place that appears at the lasing wavelength ∼ 1.40 μm.

The preliminary assessment of a Lower Hybrid Current Drive (LHCD) system for the DEMOnstration power plant (DEMO) is mainly focused on the R&D needs of the less conventional RF components of the Main Transmission Line (MTL) and of the launcher. 500 kW, CW klystrons will be used to deliver the RF power to independent Passive Active Multijunction (PAM) launcher modules at 5 GHz. This paper describes the criteria followed to investigate the optimum solution for the RF window used as vacuum barrier between the MTL and the launcher, an open issue in the LHCD system for ITER too. The best candidate, capable of withstanding a power level of, or above, 0.5 MW in CW operation and to satisfy the electrical and thermonuclear requirements, is a Pill-Box assembly, based on a thin single disk of CVD-diamond as dielectric, water cooled at the edge. A thickness of 3 mm, much shorter than half a wavelength of the TE°11 mode in the dielectric as in the conventional window (unfeasible and too expensive with CVD-diamond at these frequencies), is sufficient to limit the exerted stress at the edge under the fracture stress for a maximum pressure applied of 0.9 MPa. In this paper the simulation results of conventional and thin CVD-diamond vacuum windows are presented comparing S-parameters, losses and electric fields in both matching condition and with VSWR = 2, using WR284 and WR229 as input/output rectangular waveguide. © 2014 American Institute of Physics.

This paper presents comparison on the different intrinsic width of InGaAs PIN Photodiode. Intrinsic region is a pure semiconductor without any significant dopant species present. In this paper, it will present two different sizes of the intrinsic region for InGaAs PIN Photodiode. This photodiode will be designed by using Atlas Silvaco TCAD Tools. From the structure, the characteristics of the photodiode will be analyzed. The I-layer thickness (or width) is varied from 5μm × 20μm to 8μm × 20μm in order to investigate its effects on the current-voltage (IV) characteristics. These papers are separated into several sections consists of the basic principle, characteristics, advantages and the recent technologies of PIN Photodiode. There will be a specific section on comparison between different intrinsic widths of InGaAs PIN Photodiode.

Avalanche Photodiode based on InGaAs/InP was chosen because of the needs of high speed optical receivers and have their own advantages on high sensitivity. In this project, we focused on the effect of guard ring on InGaAs/InP avalanche photodiodes and its performance. Three types of guard ring structures are designed in APD and their current-voltage (I-V) characteristics (electric field profiles) are simulated and analyzed. In this paper, the characteristics of guard ring in InGaAs/InP are investigated using Silvaco software, TCAD tools. This paper investigates the effects of guard-ring (GR) structures on the performance of InGaAs/InP avalanche photodiode (APDs) designed in Silvaco TCAD. Three type InGaAs/InP-APDs based on P+/N-well guard ring, n+/p-substrate guard ring and no presence guard ring are designed and their electric field profiles are simulated. In others to know the best structures of InGaAs/InP avalanche photodiode structures, the current-voltage characteristics (I-V characteristics) are measured and compared. Overall, the project includes the effect and relationship of avalanche photodiode between substrate concentrations and doping, type of materials, with the breakdown voltage and leakage current were investigated. Then, the structure is applied with guard ring structure. At the end, we choose the best optimized design of avalanche photodiode based on current-voltage characteristics. From the theoretical, they conclude the important of guard ring presence in the avalanche photodiode structure in order to avoid premature breakdown and also leakage current. From the experiment, we can conclude that the best structures of InGaAs/InP avalanche photodiode is by using P+/N-well guard ring because this structure give the higher breakdown voltage and lowest leakage current.

This paper shows Electrical characterization of Dye Sensitized Solar Cell using natural dye, extracted from the pomegranate as a photo sensitizer and ZnO nanoparticles as semiconductor. The constituents of fabricated dye sensitized solar cell were working electrode, dye, electrolyte and counter electrode. ZnO nanoparticles were synthesized and used as semiconductor in working electrode. Carbon soot was used as counter electrode. The resistance of ZnO film on ITO film was found out. There was an increase in the resistance of the film and film changes from conducting to semiconducting. Photovoltaic parameters of the fabricated cell like Short circuit current, open circuit voltage, Fill factor and Efficiency were found out. This paper shows that usage of natural dyes like pomegranate juice as sensitizer enables faster and simpler production of cheaper and environmental friendly solar cell.

The present paper reports the influence in dielectric properties caused by gamma radiation. The dielectric parameters have been measured for both unirradiated and gamma irradiated 5CB nematic liquid crystal with temperature variation in the frequency range 100 Hz to 10 MHz. Dielectric permittivity with variation in temperature has also been observed. The dielectric permittivity is found to increase for gamma irradiated sample as compared to the unirradiated sample with variation in temperature and frequency and well explained in this paper.

Thermal Barrier Coatings (TBC) are used to reduce the working temperature of the high pressure turbine blade metal surface and hence permit engines to operate at higher temperatures/ efficiencies. A sensor TBC is an adaptation of existing TBCs to enhance their functionality, such that they become sensors and allow measurement of component temperatures. The sensing capability is introduced by embedding optically active materials into the TBC and by illuminating these coatings with excitation light phosphorescence can be observed. The phosphorescence carries temperature and structural information about the coating. This paper describes the first ever implementation of a sensor coating system on a full-scale jet engine. The system consists of three main components: industrially manufactured coatings, advanced remote detection optics with large stand-off distances and tailored control and readout software. The majority of coatings were based on yttrium stabilized zirconia doped with Dy and Eu, although other coatings were manufactured, too. Coatings were produced on a production line using atmospheric plasma spraying. An advanced optical system was designed, manufactured and operated permitting scanning of coated components using a wide acceptance angle. Successful measurements were taken from the nozzle guide vanes at the inlet to the turbine section and are reported in the paper.

In this paper, performance of quantum dot floating gate MOSFET memory is simulated by replacing the SiO2 tunnel oxide with high-Κ material. There are three high-k material simulated in this paper, HfO2, ZrO2, and Y2O3. As we know that high-Κ material is used nowadays to reduce leakage current, so this paper demonstrates the application of high-Κ material to reduce leakage current in non-volatile memory quantum dot based floating gate MOSFET. Simulation results of this paper show the leakage current can be suppressed by using high-Κ material as tunnel oxide up to 10 times. Furthermore, this paper also shows that the memory performance can be properly sustained. The writing and erasing time are depend on tunneling current probability which calculated using transfer matrix method. The writing time and erasing time for HfO2 and ZrO2 are 150 nanosecond and 15 nanosecond.

SEN Corporation has developed a very flexible dose pattern modulation system called “MIND+”. This system can be used for yield enhancement by compensating for variation induced by other processes. In this paper, another important feature of SEN’s single-wafer implanters is introduced. The system is called the “MILD” system, standing for “Maskless Implantation for Local Doping.” MILD provides the capability to implant dopants at any positions on a wafer without hard masks or photo-resist patterns. In this paper, MILD system operation and results will be described.

Multilayer thin films structures have received wide-spread attention due to their fast response and high efficiency. In this paper, we report the properties of PbSe/ZnSe multilayer thin films prepared by vacuum evaporation technique by sequential deposition of individual compounds. The prominent peak corresponding to (2 0 0) plane was observed in the Xray diffractogram with cubic crystal structure. The size of the crystallites are found to be 8 nm and 14 nm for the three-layer and five-layer films respectively. The absorption edge starts at 430 nm for the three-layer structures while that for the fivelayer film starts at 480 nm. The calculated optical band gaps of the three-layer and five-layer PbSe/ZnSe multilayer films are found to be 1.7 eV and 1.9 eV respectively. The electrical resitivities are found to be 2.8 × 107 Ω-cm for the three-layer film and 1.02 Ω cm for the five-layer film. The various electrical properties of the films such as mobility, carrier concentration and sheet resistance also are discussed in this paper.

Metal-Semiconductor-Metal Photodetector (MSM-PD) is a well known structure for its higher response speed due to its ultralow capacitance per area compare to other type of photodetectors. It is also compatible with FET technology and is a potential candidate as a photodetector in receiver optoelectronics integrated circuits (OEICs) [1]. Conventional MSM-PD structures have a major disadvantage of high dark current which results in higher power consumption. This problem is particularly serious for low-bandgap material. Many works have been done to suppress dark current of MSM-PD. A common approach is to incorporate Schottky barrier enhancement layer. Recent paper has reported the use of silicon-carbon (Si:C) Schottky barrier enhancement layer to suppress dark current in Ge-on-SOI MSM photodetector by more than four orders of magnitude and leading to dark current of ∼11.5 nA for an applied bias of 1.0 V [2]. Another way of reducing dark current is by using passivation layer such as a-Si:H layer. Deposition of a single or multiple layers of amorphous Si or amorphous Si alloy on crystalline silicon substrate to suppress dark current were also reported [3], [4]. In this paper, the effect of a thin un-hydrogenated amorphous silicon layer (a-Si) on the performance of Si-based MSM photodetector (MSM-PD) was studied. Thermal evaporation technique was used to deposit the a-Si layer on crystalline silicon substrate. a-Si layer was shown to decrease dark current of Si-based MSM-PD up to five orders of magnitude. a-Si layer was used as barrier enhancement layer in one MSM structure and capping layer in another structure. At applied bias of 5V, the latter structure exhibits lower dark current leading to photocurrent-to-dark current ratio of ∼ 800 (white light 15W).

This paper presents a solution to the temperature issue in High Concentration Photovoltaic (HCPV) module device by using different thermal conductive material and packing structure. In general, the open‐circuited voltage of a device reduces with the increase of temperature and therefore degrades its efficiency. The thermal conductive material we use in this paper, silicon, has a high thermal conductive coefficient (149 W/m⋅K) and steady semiconductor properties which are suitable for the application of solar receiver in HCPV module. Solar cell was soldered on a metal‐plated Si substrate with a thicker SiO2 film which acts as an insulating layer. Then it was mounted on an Al‐based plate to obtain a better heat dissipating result.