Now showing 1 - 3 of 3
  • Publication
    Thermal diffussion: a simulation based study on shallow junction formation
    ( 2012-07) ;
    N. Hamat N. H,
    ;
    Siti Fatimah
    ;
    Ultra shallow junction fabrication in future ultra large scaled integrated (ULSI) technology is one of the difficult challenges in device manufacturing. Low energy ion implantation is hte most widely used technique at present to form ultra shallow junction but research has been to overcome its limitations such as crystal damage. In this research paper, thermal diffusion from spin-on dopant (SOD) into silicon has been studied in order to form shallow junction. This study was done by simulation using TSUPREM-4 from Synopsys Inc to determine the junction depth and the sheet resistance in order to fulfill the ITRS requirements. Ultra shallow junction which is defined to be less than 30 nm in depth has been obtained through this simulation using this easy and simple spin-on dopant technique. This economical spon-on dopant (SOD) technique has been proven as one promising method for shallow junction formation in future generations.
  • Publication
    Insight on the structural aspect of ENR-50/TiO2 hybrid in KOH/C3H8O medium revealed by NMR spectroscopy
    ( 2020)
    Omar S. Dahham
    ;
    ;
    Mohamad Abu Bakar
    ;
    ;
    Abdulkader M. Alakrach
    ;
    ; ; ;
    Awad A. Al-rashdi
    The ring-opening reactions (ROR) of epoxide groups in epoxidized natural rubber/titania (ENR-50/TiO2) hybrid in potassium hydroxide/isopropanol medium were examined using NMR spectroscopy and supported by the FTIR technique. The thermal behaviour of the hybrid was also studied using TG/DTG and DSC analyses. The 1H NMR results suggested that 16.82% of ROR occurred in the hybrid, while the 13C NMR results exhibited five new peaks at δ 19.5, 71.0, 73.7, 91.7 and 94.4 ppm in the hybrid. 2D NMR, such as HMQC, HMBC and COSY techniques, further scrutinized these assignments. The FTIR spectrum exhibited Ti-O-C characteristics via the peak at 1028 cm−1. The TG/DTG results showed four steps of thermal degradation at 44–148, 219–309, 331–489 and 629–810 °C due to the existence of Ti moieties along with a polymer chain mixture (intact and ring-opened epoxide groups) of ENR-50, which in turn led to an increase in the Tg value of the hybrid to 27 °C compared to that of purified ENR-50 at −17.72 °C.
  • Publication
    Magnetic induction tomography for brain tissue imaging based on conductivity distribution for parkinson’s disease diagnosis
    Parkinson's disease is a prevalent neurodegenerative complication defined by the accumulation of alpha synuclein lewy bodies in the brain. Misdiagnosis results widespread of Parkinson’s disease because clinical diagnosis is challenging, underlining a need of a better detection technique, such as non-invasive magnetic induction tomography (MIT) technique. Non-invasive techniques for biological tissues imaging are becoming popular in biomedical engineering field. Therefore, MIT technology as a non-invasive technique has been encouraged in a medical field due to its advancement of technology in diagnosing diseases. The measurement parameters in MIT are passive electromagnetic properties (conductivity, permittivity, permeability) for biological tissue and the most dominant parameter in MIT is conductivity properties. It is uses a phase shift between a primary magnetic field and an induced field caused by a target object's conductivity. As a function of conductivity, the phase shift between the applied and secondary fields is expressed. Thus, the phase shift can be used to characterize the conductivity of a target object. The phase shift between the excitation and induced magnetic fields (EMF and IMF) reflects the change in conductivity in biological tissues. This paper focuses on the virtual simulation by using COMSOL Multi-physics for the design and development of MIT system that emphasizes on single channel magnetic induction tomography for biological tissue (bran tissue) imaging based on conductivity distribution for Parkinson’s disease diagnosis. The develop system employs the use of excitation coils to induce an electromagnetic field (e.m.f) in the brain tissue, which is then measured at the receiving side by sensors. The proposed system is capable of indicating Parkinson’s disease based on conductivity distribution. This method provides the valuable information of the brain abnormality based on differences of conductivities of normal brain and Parkinson’s disease brain tissues.