Design Optimization of the graded AlGaN/GaN HEMT device performance based on material and physical dimensions

Design optimization of the traditional AlGaN/GaN HEMT device has been comprehensively conducted in achieving improved performance and current handling capability using the Synopsys’ Sentaurus TCAD tool. Varying material and physical considerations, specifically investigating the effects of graded barriers, spacer interlayer, material selection for the channel as well as study of the effects in the physical dimensions of the HEMT have been extensively carried out. Critical figure-of-merits (FOMs) specifically the DC characteristics, 2DEG concentrations and mobility of the heterostructure device have been evaluated. Significant observations include enhancement of maximum current density by 63% while the electron concentration was found to propagate by 1020 cm-3 in the channel. This work aims to provide tactical optimization to traditional HFETs, rendering its application as power amplifiers, MMICs and RADAR, which requires low noise performance and very high RF design operations. Analysis in covering the breadth and complexity of heterostructure devices has been carefully executed through extensive TCAD modelling and the end structure obtained has been optimized to provide best performance

Mapping the field of microbial fuel cell: a quantitative literature review (1970–2020)

Microbial fuel cell (MFC) has received much attention in the last decade as a promising technology to simultaneously generate electricity and decontaminate wastewater. This study aims to quantitatively review the published literature on MFC, published in the period of 1970–2020, based on the Web of Science (WoS) database. For the first time in literature, a comprehensive quantitative review of MFC has been conducted by employing the technique of bibliometric and content analyses. A total of 11,397 publications have been retrieved from WoS, out of which 81.6% are research articles. The evaluation in the field of MFC has been mapped in various categories, such as publication history, publication distribution, subject category distribution, leading journals, leading countries and leading organizations in MFC research. Additionally, content analysis has been conducted to unearth the research trends in MFC; and some hot research topics in MFC have been spotted. Results depict that the period 2011–2020 has been the most appreciating era for MFC research, as it contributed 87% of the total publications. Among the subject categories, energy fuel and microbiology lead with contributions of 26.5% for each, butthe overall growth of the energy fuel category in the last decade has been the highest. Out of 1,147 journals publishing MFC research, Bioresource Technology is the leading one; and countries like China, USA and India are the main hub of MFC research with 26.47%, 16.95% and 7.69% contributions in publications, respectively. The hottest topics in MFC research are nanoparticles, catalysts, air electrodes, graphene electrodes, power enhancement, air cathode and nitrogen removal. Moreover, major research areas are engineering, energy fuels and biotechnology with each contribution 26.5% of the total publications

Effects of Gate Stack Structural and Process Defectivity on High-k Dielectric Dependence of NBTI Reliability in 32 nm Technology Node PMOSFETs

We present a simulation study on negative bias temperature instability (NBTI) induced hole trapping in E′ center defects, which leads to depassivation of interface trap precursor in different geometrical structures of high-k PMOSFET gate stacks using the two-stage NBTI model. The resulting degradation is characterized based on the time evolution of the interface and hole trap densities, as well as the resulting threshold voltage shift. By varying the physical thicknesses of the interface silicon dioxide (SiO2) and hafnium oxide (HfO2) layers, we investigate how the variation in thickness affects hole trapping/detrapping at different stress temperatures. The results suggest that the degradations are highly dependent on the physical gate stack parameters for a given stress voltage and temperature. The degradation is more pronounced by 5% when the thicknesses of HfO2 are increased but is reduced by 11% when the SiO2 interface layer thickness is increased during lower stress voltage. However, at higher stress voltage, greater degradation is observed for a thicker SiO2 interface layer. In addition, the existence of different stress temperatures at which the degradation behavior differs implies that the hole trapping/detrapping event is thermally activated

Proceedings of International Technical Postgraduate Conference 2022

This conference proceedings contains articles on the various research ideas of the academic & research communities presented at the International Technical Postgraduate Conference 2022 (TECH POST 2022) that was held at Universiti Malaya, Kuala Lumpur, Malaysia on 24-25 September 2022. TECH POST 2022 was organized by the Faculty of Engineering, Universiti Malaya. The theme of the conference is “Embracing Innovative Engineering Technologies Towards a Sustainable Future”.  TECH POST 2022 conference is intended to foster the dissemination of state-of-the-art research from five main disciplines of Engineering: Electrical Engineering, Biomedical Engineering, Civil Engineering, Mechanical Engineering, and Chemical Engineering. The objectives of TECH POST 2022 are to bring together innovative researchers from all engineering disciplines to a common forum, promote R&D activities in Engineering, and promote the dissemination of scientific knowledge and research know-how between researchers, engineers, and students. Conference Title: International Technical Postgraduate Conference 2022Conference Acronym: TECH POST 2022Conference Date: 24-25 September 2022Conference Location: Faculty of Engineering, Universiti Malaya, Kuala Lumpur Malaysia (Hybrid Mode)Conference Organizers: Faculty of Engineering, Universiti Malaya, Kuala Lumpur, Malaysia