K. Anwar

Nuclear matter properties, phenomenological theory of clustering at the nuclear surface, and symmetry energy

We present a phenomenological theory of nuclei which incorporates clustering at the nuclear surface in a general form. The theory explains the recently extracted large symmetry energy at low densities of nuclear matter and is consistent with the static properties of nuclei. In phenomenological way clusters of all sizes, shapes along with medium modifications are included. The importance of quartic term in symmetry energy is demonstrated at and below the equilibrium density in nuclear matter. It is shown that it is related both to clustering as well as to the contribution of three-nucleon interaction to the equation of state of neutron matter. Reasons for these are discussed. Due to clustering the neutron skin thickness in nuclei reduces significantly.

WSS Investigation in Microfluidic FFS Channel at Re 500

Wall shear stress (WSS) is one of the important variables in microfluidic devices. In this paper WSS distribution for a microfluidic device in Forward Facing Step (FFS) configuration has been investigated using Reynolds number 500 and step height 1μm. Numerical simulation was performed usingAnsys-CFX software with the assumption of Newtonian fluid and laminar condition. The simulation result showed that wall shear stress distribution increased after the fluid passing through the step.

Natural Heat Convection Analysis on Cylindrical Al Slug of LED

This paper presents the characterization of a single chip high power LED package through simulation. Ansys version 11 was used for the simulation. The characterization of the LED package with aluminum cylindrical heat slug was carried out under natural convection condition at ambient temperature of 25°C. The junction temperature and the stress of the LED chip was assesed. The LED chip was powered with input power of 0.1 W and 1 W and the heat dissipation was assesed. Results showed that that the junction temperature and the Von Mises Stress of the single chip LED package increases with the increased input power.

Investigation of Surface Roughness on Platinum Deposited Wafer after Reactive Ion Etching Using SF6+Argon Gaseous

This paper investigates the factors that affect the surface roughness on a Platinum deposited wafer after reactive ion etching (RIE) using a combination of SF6 and Argon gaseous. A total of three controllable process variables, with 8 sets of experiments were scrutinized using a systematically designed design of experiment (DOE). The three variables in the investigation are ICP power, Bias power, and working pressure. The estimate of the effect calculated for ICP power, Bias power, and working pressure are-4.9288, -6.2383, and-4.7223 respectively. All three factors gave negative effects. This implies that the surface roughness decreases when ICP power, Bias power, and working pressure is high. The Bias Power is the most influential factor followed by ICP Power, and working pressure.

Fibrous Material Density Difference Analysis Using Light Reflectance

The objective of this work is designed and fabricated a lab module tester to differentiate the different type of printing paper quality which available commercially was done. Laser light source was used to differentiate the quality of printing paper. The concept light reflectance on surface material was used in this study. The photodiode was used as photo detector to detect the reflected light from the surface of printing paper. The laser diode and photodiode were placed in a box which the box named light box. The laser was used to emit light on the sample and the photodiode detects light intensity from the surface printing paper in the light box. Different level of intensity will have different value of voltage output. The differentiation on the different type of printing paper including of 70 g/m2, 80 g/m2 and 100 g/m2 were done respectively. The result showed that the 100 g/m2 printing paper has a higher reflected voltage output compared to 80 g/m2 and 70 g/m2 printing paper.

Fibrous Material Surface Reflectance Analysis

The light inspection on surface finishing of most product measurement is an important feature in the industries. In this study, a lab module tester for examination on the different type quality of tissue paper quality was done. The light reflectance element was used in this study to differentiate the quality of tissue paper. The laser diode and photodiode was used as manipulator to differentiate the tissue paper and photo detector to detect the reflected light from the surface of tissue paper. The both of laser diode and photodiode were placed in a light box. Different level of intensity reflected from the surface material will have different voltage output. The result showed that the total ply high quality tissue paper has a higher reflected voltage output compared to low quality tissue paper.

Velocity Profile Investigation of FFS Microchannel at Re 100

Recently, microfluidics system has been widely employed in various areas for instance biomedical,pharmaceuticals and cell biological researchdue to its advantages. The flow behavior in microchannels with different cross-sections has been topic in previous studies. In this paper, numerical simulation of fluid flow in Forward Facing Step (FFS) configuration was performed to investigate velocity profile after the step. Reynolds numbers (Re) 100 with different step heights, 1μm and 3μm were used to observe trend occurs in the flow characteristics. The result illustrated an increase of velocity distribution with the increase of the step height.

Physical Characterization of BST with Different (x’) Ratios

Nowdays Barium strontium titanate (BST) can be applied into many fields of engineering. Its properties attracted more researchers to research and apply it into many fields of study. In this work, sol-gel method of preparing barium strontium titanate (BST) has been used. This work was done with 4 different ratio of x with 4 different deposition layers. The main purpose of this work is to investigate the relation between the ratio of barium (Ba) with different deposition layer and the surface of the substrate. Atomic force microscopy (AFM) was used in whole work to investigate the crystalline structure and surface roughness of the BST thin films.

BaxSr1-x TiO3 Different Thickness Analysis Using Sol Gel Approach

Barium Strontium Titanate (BST) a common topic in the microelectronic field for many devices which is mainly on dynamic random access memories (DRAM). There are many methods of preparing BaxSr1-xTiO3; barium strontium titanate. In this work, sol-gel method was used as it has some advantages like better homogeneity, lower cost, lower processing temperature and easier fabrication. BaxSr1-xTiO3 solution was deposited on the silicon substrate of 4 different thicknesses with different ratio of the concentration of Barium (Ba). The thickness of the thin film has a linear increase as the Ba content increases.

Surface Roughness and Wettability Correlation on Etched Platinum Using Reactive Ion Ecthing

As the world of semiconductor is moving towards smaller and high-end applications, the quality of the bonding adhesion for wire bonding is very critical. Although aluminium has been the metallization of choice in integrated circuits, it can be easily oxidized during high temperature and pressure. On the other hand, Platinum metallization layer has high thermal coefficient resistance and inert to oxygen. This paper reports the correlation between surface roughness and the wettability in the form of contact angle for Platinum deposited wafer etched using Inductively Couple Plasma-Reactive Ion Etching (ICP-RIE). Surface roughness was measured using AFM while contact angle was obtained via droplet test. The results clearly suggested that both surface roughness and wettabily, calculated by its contact angle value has the same trend. Surface roughness is directly proportional to the contact angle. This indicates that surface roughness have great influence on the surface wettability. Therefore, the adhesion for wire bonding process on platinum metallization which can be used in high end applications can be controlled by its surface roughness and wettability.