Garuda - Garba Rujukan Digital

Comprehensive identification of sensitive and stable ISFET sensing layer high-k gate based on ISFET/electrolyte models Ahmed M. Dinar; A. S. Mohd Zain; F. Salehuddin
International Journal of Electrical and Computer Engineering (IJECE) Vol 9, No 2: April 2019
Publisher : Institute of Advanced Engineering and Science

The ISFET sensing membrane is in direct contact with the electrolyte solution, determining the starting sensitivity of these devices. A SiO2 gate dielectric shows a low response sensitivity and poor stability. This paper proposes a comprehensive identification of different high-k materials which can be used for this purpose, rather than SiO2. The Gouy-Chapman and Gouy-Chapman-Stern models were combined with the Site-binding model, based on surface potential sensitivity, to achieve the work objectives. Five materials, namely Al2O3, Ta2O5, Hfo2, Zro2 and SN2O3, which are commonly considered for micro-electronic applications, were compared. This study has identified that Ta2O5 have a high surface potential response at around 59mV/pH, and also exhibits high stability in different electrolyte concentrations. The models used have been validated with real experimental data, which achieved excellent agreement. The insights gained from this study may be of assistance to determine the suitability of different materials before progressing to expensive real ISFET fabrication.

Side lobe reduction in array antenna by using novel design of EBG Muhannad Kaml Abdulhameed; M. S. Mohamad Isa; I. M. Ibrahim; Z. Zakaria; Mowafak K. Mohsen; Mothana L. Attiah; Ahmed M. Dinar
International Journal of Electrical and Computer Engineering (IJECE) Vol 10, No 1: February 2020
Publisher : Institute of Advanced Engineering and Science

A novel design of EBG is used to replace the mushroom like EBG for surrounding the array patch antenna. In order to improve its radiation performances, Electromagnetic band stop for reducing the surface waves effects is presented. The novel design of Triple Side Slotted EBG (TSSEBG) showed an improvement in the antenna efficiency, directivity and gain as compared to the reference antenna without using EBG, due to reduce the surface waves effects which leads to decrease the side lobes. TSSEBG has been introduced by some modifications in conventional mushroom-like EBG structure. Reducing the complexity was achieved by reducing the number of unit cells and vias, in case of used TSSEBG instead of mushroom like EBG. Additionally, the TSSEBG provided triple band gap compared with mushroom like EBG structure which had only one band gap frequency at 6 GHz. The placement of TSSEBG is a flexible structure which provides a good choice in the antenna applications. The simulation results of array patch antenna with and without mushroom like EBG and TSSEBG are arranged in Table 1. This structure has vast applications in satellite communications.

Performance analysis of high-k materials as stern layer in ion-sensitive field effect transistor using commercial TCAD Ahmed M. Dinar; AS Mohd Zain; F. Salehuddin; Mowafak K. Mohsen; Mothana L. Attiah; M. K. Abdulhameed
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 6: December 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i6.12852

High-k materials as a STERN Layer for Ion-Sensitive-Field-Effect-Transistor (ISFET) have improved ISFET sensitivity and stability. These materials decrease leakage current and increase capacitance of the ISFET gate toward highest current sensitivity. So far, many high-k materials have been utilized for ISFET, yet they were examined individually, or using numerical solutions rather than using integrated TCAD environment. Exploiting TCAD environment leads to extract ISFET equivalent circuit parameters and performs full analysis for both device and circuit. In this study we introduce a comprehensive investigation of different high-k material, Tio2, Ta2O5, ZrO2, Al2O3, HfO2 and Si3N4 as well as normal silicon dioxide and their effects on ISFET sensitivity and stability. This was implemented by developing commercial Silvaco TCAD rather than expensive real fabrication. The results confirm that employing high-k materials in ISFET outperform normal silicon dioxide in terms of sensitivity and stability. Further analysis revealed that Titanium dioxide showed the highest sensitivity followed by two groups HfO2, Ta2O5 and ZrO2, Al2O3 respectively. Another notable exception of Si3N4 that is less than other materials, but still have higher sensitivity than normal silicon dioxide. We believe that this study opens new directions for further analysis and optimization prior to the real cost-ineffective fabrication.

Electronically controlled radiation pattern leaky wave antenna array for (C band) application Mowafak K. Mohsen; M. S. M. Isa; Z. Zakaria; A. A. M. Isa; M. K. Abdulhameed; Mothana L. Attiah; Ahmed M. Dinar
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 2: April 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i2.11126

This paper provides an insight of a new, leaky-wave antenna (LWA) array. It holds the ability to digitally steer its beam at a fixed frequency by utilizing only two state of bias voltage. This is done with acceptable impedance matching while scanning and very little gain variation. Investigation is carried out on LWAs’ control radiation pattern in steps at a fixed frequency via PIN diodes switches. This study also presents a novel half-width microstrip LWA (HWMLWA) array. The antenna is made up of the following basic structures: two elements and reconfigurable control cell with each being comprised of two diodes and two triangle patches. A double gap capacitor in each unit cell is independently disconnected or connected via PIN diode switch to achieve fixed-frequency control radiation pattern. The reactance profile at the microstrip’s free edge and thus the main beam direction is changed once the control-cell states are changed. The main beam may be directed by the antenna between 61o and 19o at 4.2 GHz. C band achieved the measured peak gain of the antenna of 15 dBi at 4.2 GHz beam scanning range.

Energy-efficient user association mechanism enabling fully hybrid spectrum sharing among multiple 5G cellular operators Mothana L. Attiah; A. A. Md Isa; Zahriladha Zakaria; Ahmed M. Dinar; M . K. Abdulhameed; Mowafak K. Mohsen
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 6: December 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i6.13058

Spectrum sharing (SS) is a promising solution to enhance spectrum utilization in future cellular systems. Reducing the energy consumption in cellular networks has recently earned tremendous attention from diverse stakeholders (i.e., vendors, mobile network operators (MNOs), and government) to decrease the CO2 emissions and thus introducing an environment-friendly wireless communication. Therefore, in this paper, joint energy-efficient user association (UA) mechanism and fully hybrid spectrum sharing (EE-FHSS) approach is proposed considering the quality of experience QoE (i.e., data rate) as the main constraint. In this approach, the spectrum available in the high and low frequencies (28 and 73 GHz) is sliced into three portions (licensed, semi-shared, and fully-shared) aims to serve the users (UEs) that belong to four operators in an integrated and hybrid manner. The performance of the proposed QoE-Based EE UA-FHSS is compared with the well-known maximum signal-to-interference-plus-noise ratio (max-SINR UA-FHSS). Numerical results show that remarkable enhancement in terms of EE for the four participating operators can be achieved while maintaining a high degree of QoE to the UEs.

Novel design of triple-bands EBG M. K. Abdulhameed; M. S. Mohamad Isa; Z. Zakaria; I. M. Ibrahim; Mowafak K. Mohsen; Ahmed M. Dinar; Mothana L. Attiah
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 4: August 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i4.12616

This paper presents a novel design for a triple band electromagnetic band gap (EBG) structures that provides three band gaps, with operating frequency of below 10 GHz, while the ordinary mushroom like EBG structure gives only one band gap. Complexity reduction (reduce the number of unit cells and Vias) was achieved by replacing each four cells of the Mushroom like EBG by the one of double slotted type EBG (DSTEBG) or triple side slotted EBG (TSSEBG). The Mushroom like EBG was further modified by increasing its size and inserting the slots to gain more capacitance and inductance which resulted into triple band stop.The new designs wer compared with bandwidths expressed by other EBGs and -20 dB cut-off frequencies. The size of EBG element and the gap between EBG elements, and slot width were investigated to analyse their effect on the transmission response. The structures were designed from 2.54 mm Rogers RT/Duroid 6010 substrate with relative permittivity of 10.2 and loss tangent of 0.0023. Among the investigated EBGs, the single band mushroom like EBG and the triple band of the TSSEBG demonstrated better bandwidth and lower resonance frequency performance, whereas the DSTEBG showed larger bandwidth for the first and third band. The proposed EBGs could be useful in the antenna design and other microwave circuits.

Enhancement of boresight radiation for leaky wave antenna array Mowafak K. Mohsen; M. S. M Isa; A. A. M. Isa; M. K. Abdulhameed; Mothana L. Attiah; Ahmed M. Dinar
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 5: October 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i5.12631

An array of half-width microstrip leaky-wave antennas (HW-MLWAs) of two uniform elements was designed to obtain maximum boresight radiation. Achieve this, two uniform of HW-MLWAs are placed at 180◦ and fed by a probe located at the center between the elements, two uniforms of HW-MLWAs, loaded terminated by 50Ω lumped element. Two beams from two branches individual merge to form the resultant directive beam. The simulation represents the susceptibility of the proposed array of uniform HW-MLWAs to the radiation broadside direction effectively. The predict bandwidth matched of the array is 582 MHz (4.18–4.76 GHz). The direction of its main beam in boresight happens over a wide 13%, relatively (4.18-4.76 GHz) band. The proposed peak gain at the boresight direction of the array is 9.91 dBi.

Hybrid multi-independent mmWave MNOs assessment utilising spectrum sharing paradigm for 5G networks Mothana L. Attiah; A. A. Md Isa; Zahriladha Zakaria; M. K. Abdulhameed; Mowafak K. Mohsen; Ahmed M. Dinar
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 3: June 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i3.11131

Spectrum sharing paradigm (SSP) has recently emerged as an attractive solution to provide capital expenditure (CapEx) and operating expenditure (OpEx) savings and to enhance spectrum utilization (SU). However, practical issues concerning the implementation of such paradigm are rarely addressed (e.g., mutual interference, fairness, and mmWave base station density). Therefore, in this paper, we proposed ultra-reliable and proportionally fair hybrid spectrum sharing access strategy that aims to address the aforementioned aspects as a function of coverage probability (CP), average rate distributions (ARD), and the number of mmWave base stations (mBSs). In this strategy, the spectrum is sliced into three parts (exclusive, semi-pooled, and fully pooled). A typical user that belongs to certain operator has the right to occupy a part of the spectrum available in the high and low frequencies (28 and 73 GHz) based on an adaptive multi-state mmWave cell selection scheme (AMMC-S) which associates the user with the tagged mBS that offers a highest SINR to maintain more reliable connection and enrich the user experience. Numerical results show that significant improvement in terms of ARD, CP, fairness among operators, and maintain an acceptable level of mBSs density.

Impact of Gouy-Chapman-Stern model on conventional ISFET sensitivity and stability Ahmed M. Dinar; AS Mohd Zain; F. Salehuddin; M.K. Abdulhameed; Mowafak K. Mohsen; Mothana L. Attiah
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 6: December 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i6.12838

Utilizing Gouy-Chapman-Stern model can improve ISFET sensitivity and stability using Stern layer in direct contact with electrolyte in ISFET sensing window. However, this model remains a challenge in mathematical way, unless it’s re-applied using accurate simulation approaches. Here, we developed an approach using a commercial Silvaco TCAD to re-apply Gouy-Chapman-Stern model as ISFET sensing membrane to investigate its impact on sensitivity and stability of conventional ISFET. Sio2 material and high-k Ta2O5 material have been examined based on Gouy-Chapman and Gouy-Chapman-Stern models. Results shows that the ISFET sensitivity of SiO2 sensing membrane is improved from ~38 mV/pH to ~51 mV/pH and the VTH shift stability is also improved. Additionally, the results indicate that the sensitivity of Ta2O5 is 59.03 mV/pH that hit the Nearnst Limit 59.3 mV/pH and achieves good agreements with mathematical model and previous experimental results. In conclusion, this investigation introduces a real validation of previous mathematical models using commercial TCAD approach rather than expensive fabrication that paves the way for further analysis and optimization.

Title

Found 9 Documents
Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title Search

Found 9 Documents Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title

Found 9 Documents
Search