Characterization of electrostatic discharge threshold voltage of phase-shift mask reticle

A reticle is a stencil used in lithography process for forming integrated circuit (IC) on silicon substrate. It consists of a thin (100 nm) coating of masking metallic patterned (features) with critical dimension (CD) of nanometers on a thicker quartz substrate. The features can be damaged by electrostatic discharge (ESD) when exposed to the environment electrostatic charge and caused deformed IC and eventually device difunctional. Semiconductor equipment materials industry (SEMI) standard established the allowable electrostatic charge on reticle based on the characterization of ESD threshold voltage on binary reticle. However, there is another type of reticle which is phase-shift mask (PSM), has not been characterized for its ESD threshold voltage. A direct current (DC) voltage is applied directly to the structures with CD of 80 nm, 110 nm, and 160 nm. The surface current is recorded at all levels of stress from 1 to 100 V. The current–voltage (IV) curve and physical inspection results for each cell are then reviewed and classified. The results yielded which no electric field induced migration (EFM) defect and breakdown voltage occurred at any of the structures. The cathode’s metal work function has been identified as the factor that influences the PSM reticle ESD threshold voltage.

A Dual/Single Wideband Switchable Metamaterial Absorber at Low Frequency

Based on PIN diode and resistive film, a dual/single wideband switchable metamaterial absorber at low frequency is presented in this paper. Its absorption is over 90% from 0.8GHz to 1.5GHz and from 4.2GHz to 5.2GHz while the PIN diode operates in forward biased condition. On the contrary, with the PIN diode acting in reverse biased condition, the above 90% absorption occurs from 1.1GHz to 3.2GHz. The surface current distributions at the absorption frequencies are monitored to explain the reason of wideband absorption. The simulation results show that the absorption property of the metamaterial absorber is polarization-sensitive. The metamaterial absorber possesses the advantages of simple structure, wideband, dual/single band, and switchable performance.

Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow

The theory of surface wave generation, in viscous flows, is modified by replacing the linear-logarithmic shear velocity profile, in the air, with a model which links smoothly the linear and logarithmic layers through the buffer layer. This profile includes the effects of air flow turbulence using a damped mixing-length model. In the water, an exponential shear velocity profile is used. It is shown that this modified and coupled shear-velocity profile gives a better agreement with experimental data than the coupled linear-logarithmic, non smooth profile, (in the air)–exponential profile (in the water), widely used in the literature. We also give new insights on retrograde modes that are Doppler shifted by the surface velocity at the air-sea interface, namely on the threshold value of the surface current for the occurrence of a second unstable mode.

Постростовые технологии каскадных фотоэлектрических преобразователей на основе A-=SUP=-3-=/SUP=-B-=SUP=-5-=/SUP=--гетероструктур

Investigation and development of the post-growth technology for fabricating multi-junction photovoltaic converters based on GaInP/GaInAs/Ge heterostructure has been carried out. Antireflection coating, ohmic contacts and mesa-structure forming stages have been reviewed. The technology of n+-GaAs contact layer etching with the help of plasma-chemical, liquid and ion-beam etching has been investigated. Antireflection coefficient of radiation from the heterostructure with TiOx/SiO2 (x close to 2) antireflection coating surface was less then 3% in wavelength range 450-850 nm. The value of contact resistance for n- and p-type conductivity was 3E−5 − 3E−6 ohm · cm2, the decrease of photosensitive region shading degree at increased bus-bar conductivity has been archived. The mesa-structure surface current leakage decreased to the value of E-9 A at voltage less then 1 V.

Thermo-diffusion impacts on the flow of an elastico-viscous fluid over an inclined heated plane with magnetized wall

The focus is in this article is to scrutinize the simultaneous significances of magnetic diffusion, thermo-diffusion and angular location on the hydromagnetic flow of an elastico-viscous fluid over an inclined heated plane with magnetized wall. The flow medium is considered to be uniformly permeable (Darcy-Brinkman porous medium) and the flow of the fluid is considerably affected due to the appearance of a strong magnetic field in the direction normal to the flow surface. The significances of Hall current, induced magnetic field and Coriolis force on flow nature is also included in the study. The leading non-dimensionalized equations are explored by regular perturbation analysis. Ultimately, the expressions for velocity field, induced magnetic field, temperature and concentration are obtained. We further derived the surface skin friction, surface current density, heat and mass fluxes. The computation of results is performed with the aid of Mathematica software and results are presented in graphical and tabular forms for distinct flow impacting parameters. Numerical simulation explores that mass diffusion factor brings growth in the fluid velocity, temperature and normal induced magnetic field while it reduces the main induced magnetic field. Magnetic diffusion develops the primary flow and primary induced magnetic field and lessens the normal flow and normal induced magnetic field. Inclination angle of the heated plane upgrades primary induced magnetic field while downgrading normal induced magnetic field.

Effect of Seawater and Fly Ash Contaminants on Insulator Surfaces Made of Polymer Based on Finite Element Method

Polymer is an insulating substance that has become increasingly popular in recent years due to its benefits. Light density, superior dielectric and thermal properties, and water-resistant or hydrophobic properties are only a few of the benefits. The presence of impurities or pollutants on the insulator’s surface lowers its dielectric capacity, which can lead to current leakage. The influence of seawater and fly ash pollutants on the distribution of the electric field and the current density of the insulator was simulated in this study. The finite element method was used to execute the simulation (FEM). Polymer insulators are subjected to testing in order to gather current leakage statistics. The tested insulator is exposed to seawater pollution, which varies depending on the equivalent salt density deposit value (ESDD). The pollutant insulator for fly ash varies depending on the value of non-soluble deposit density (NSDD). The existence of a layer of pollutants increased the value of the electric field and the value of the surface current density, according to the findings. Both in simulation and testing, the ESDD value of seawater pollutants and the NSDD value of fly ash contaminants influenced the value of the leakage current that flowed. The greater the ESDD and NSDD values are, the bigger the leakage current will be.

Assimilating realistically simulated wide-swath altimeter observations in a high-resolution shelf-seas forecasting system

The impact of assimilating simulated wide-swath altimetry observations from the upcoming Surface Water and Ocean Topography (SWOT) mission is assessed using observing system simulation experiments (OSSEs). These experiments use the Met Office 1.5 km resolution North West European Shelf analysis and forecasting system. In an effort to understand the importance of future work to account for correlated errors in the data assimilation scheme, we simulate SWOT observations with and without realistic correlated errors. These are assimilated in OSSEs along with simulated observations of the standard observing network, also with realistic errors added. It was found that while the assimilation of SWOT observations without correlated errors reduced the RMSE (root mean squared error) in sea surface height (SSH) and surface current speeds by up to 20 %, the inclusion of correlated errors in the observations degraded both the SSH and surface currents, introduced an erroneous increase in the mean surface currents and degraded the subsurface temperature and salinity. While restricting the SWOT data to the inner half of the swath and applying observation averaging with a 5 km radius negated most of the negative impacts, it also severely limited the positive impacts. To realise the full benefits in the prediction of the ocean mesoscale offered by wide-swath altimetry missions, it is crucial that methods to ameliorate the effects of correlated errors in the processing of the SWOT observations and account for the correlated errors in the assimilation are implemented.

Design and prototyping of GSM-bluetooth based solar energy remote monitoring system

Purpose The purpose of this study is to monitor the surface cooling of the photovoltaic (PV) panel and the effect of the dust accumulated on the panel surface on the electrical efficiency remotely and instantaneously. Design/methodology/approach An autonomous system has been designed that can measure and record the PV surface temperature, the amount of dust on the surface, current, voltage and power values at certain intervals. It can also perform surface cooling and cleaning with water cycle when the temperature and dust amount reach certain threshold values and transmit these values to the user via global system for mobile communications module, Bluetooth module and graphically with a touchscreen liquid crystal display panel. Thus, it is aimed to benefit from PV at the maximum level, and it was installed in Kahramanmaras Sütçü Imam University Faculty of Engineering and Architecture. Findings An increase in power was observed for PV surface cooling and surface dust removal by 3.78% and 45.99%, respectively. Originality/value This system is of vital importance in terms of time and energy-saving, especially for solar plants far from the city center, which are difficult to access because of climatic conditions. In other hand for future studies, it is foreseen that more efficiency gains can be achieved by using artificial intelligence and image processing techniques.

Dual Band Patch Antenna Based on Letter Slotted DGS for 5G Sub-6GHz Application

To design a multiband microstrip patch antenna, the Defected Ground Structure (DGS) technique is applied to add a disturbance effect in the surface current distribution and create a multi-resonance frequency. Furthermore, and in the aim to achieve a high gain, a high superstrate is added above the basic antenna design. The developed antenna is dedicated to the 5G sub 6GHz band application. The proposed antenna is based on RO5880 dielectric substrate of ɛ=2.2 and has an overall dimension of 77×70.11×1.6 mm3. The antenna operates at a sub 6GHz frequency range (at 4.53 to 4.97 GHz) and fits in 5G band application standard. Using CST Studio Suite Electromagnetics (EM) Solver, antenna’s performances are investigated; an average gain of 5 dB with acceptable radiation efficiency is obtained at the operating frequencies, suitable for sub-6GHz 5G application. The proposed antenna is fabricated, and experimental analysis is conducted using ROHDE & SCHWARZ ZVB20 network analyser, which shows a good agreement with the simulation analysis.