Muammar Mohamad Isa
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Muammar Mohamad Isa
Official Name
Muammar , Mohamad Isa
Alternative Name
Isa, M. M.
Mohamad Isa, M.
Isa, Muammar Mohamad
Mohamad Isa, Muammar
Isa, M. Mohamad
Main Affiliation
Scopus Author ID
57202563525
Researcher ID
N-2105-2017

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  • Publication
    Remazol orange dye sensitized solar cell
    ( 2017-01-03)
    Siti Salwa Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Muda M.R.
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Nurul Izza Mohd Nor
    ;
    Norhawati Ahmad
    ;
    Nazuhusna Khalid
    ;
    Nur M. Selamat
    ;
    Nur Asyikin Mohd Anhar
    Water based Remazol Orange was utilized as the dye sensitizer for dye sensitized solar cell. The annealing temperature of TiO2 working electrode was set at 450 °C. The performance of the device was investigated between dye concentrations of 0.25 mM and 2.5 mM at three different immersion times (3, 12 and 24 hours). The adsorption peak of the dye sensitizer was evaluated using UV-Vis-Nir and the device performance was tested using solar cell simulator. The results show that the performance was increased at higher dye concentration and longer immersion time. The best device performance was obtained at 0.2% for dye concentration of 2.5 mM immersed at 24 hours.
  • Publication
    Application of Taguchi method in optimization of structural parameters in self-switching diode to improve the rectification performance
    ( 2020-01-08)
    Nor Farhani Zakaria
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Zarimawaty Zailan
    ;
    Mokhar M.B.M.
    ;
    Juhari N.
    This paper presents the use of Taguchi method in the optimization process of a Self-switching Diode (SSD) as a Terahertz rectifier to obtain the optimal parameters for rectification. The rectification performance is mainly contributed by a parameter known as curvature coefficient, γ which is derived from the current-voltage (I-V) behavior of the device and can be altered by varying the device's geometrical structure. The parameters involved are the channel length, channel width and trenches width of the device, and the rectification performance are observed based on the peak of γand its corresponding bias voltage. Using Taguchi method for design of experiment (DOE), effects on the interaction among these parameters are investigated by employing the orthogonal array and evaluation of the signal-to-noise (S/N) ratio both in the peak of γand its corresponding bias voltage. The proposed parameters using this method showed γ peak of 32 V-1 and 30 V-1 at DC bias of 30 mV and zero-bias, respectively.
  • Publication
    Numerical Simulation and Parameters Variation of Silicon Based Self-Switching Diode (SSD) and the Effect to the Physical and Electrical Properties
    ( 2020-12-14)
    Tan Y.L.
    ;
    Zakaria N.F.
    ;
    Shahrir Rizal Kasjoo
    ;
    Safizan Shaari
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Rahim A.F.A.
    Investigation of SOI based self-switching diode (SSD) by numerical simulation for RF -DC harvesting application is presented. The rectification performance of the SSD is based on the curvature coefficient, ? and current responsivity, ß which are closely related to the I-V characteristic of a non-linear device. In this work, the structural parameters are varied to observe the electrical and physical characteristics with the aid of ATLAS Silvaco simulation tools. The rectification performance in each variation is then compared, with the highest value of ? and ß observed at 25.20 V and 12.60 V, respectively. By identifying and understanding these control factors and their effects, distinctive variations of the structural parameters by using a more deliberate optimization method can be proposed for further improvement on the rectification performance.
  • Publication
    Linear modelling of novel InGaAs/InAlAs/InP pHEMT for low noise applications
    ( 2017-01-03)
    En A.Y.
    ;
    Norhawati Ahmad
    ;
    Muammar Mohamad Isa
    ;
    Siti Salwa Mat Siti
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nazuhusna Khalid
    ;
    Nurul Izza Mohd Nor
    ;
    Shahrir Rizal Kasjoo
    ;
    Missous M.
    Linear modelling of novel InGaAs/InAlAs/InP pHEMT for low noise applications is substantial to the future transistors that will operate in high speed and low noise conditions. The novel pHEMT is constructed by sandwiching two different materials together with different lattice constants, for instance InGaAs and InAlAs in order to form a heterojunction in between. However, InP is only utilised to be the substrate base of pHEMT. In the modelling process, extrinsic and intrinsic parameters need to be extracted. Briefly, a high accuracy transistor modelling enables designers to predict the real output of a circuit before it can be fabricated onto an actual chip.
  • Publication
    Low voltage low power FGMOS based current mirror
    ( 2017-11-22)
    Nurulain D.
    ;
    Musa F.A.S.
    ;
    Muammar Mohamad Isa
    ;
    Norhawati Ahmad
    ;
    Shahrir Rizal Kasjoo
    This paper presents the comparison of a conventional current mirror with the one utilizing floating gate MOSFET transistors (FGMOS) to achieve low power (LP) and low voltage (LV) design. The device structure has been simulated with 0.1μ CMOS technology and 1.2V voltage supply by using SAED 90nm PDK with the Synopsys Custom Designer tool. The FGMOS circuit has shown to have low power consumption of 9.62mW, smaller threshold voltage of 0.2V and Iout of 20 mA. The improvement of 40.1% from conventional current mirror has shown the LV and LP capability of FGMOS transistor.
  • Publication
    Small signal modelling of novel InGaAs/InAlAs/InP pHEMT for high frequency applications
    ( 2017-01-03)
    Xian O.J.
    ;
    Norhawati Ahmad
    ;
    Muammar Mohamad Isa
    ;
    Siti Salwa Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nazuhusna Khalid
    ;
    Nurul Izza Mohd Nor
    ;
    Shahrir Rizal Kasjoo
    ;
    Missous M.
    HEMT is a GaAs based field effect transistor that retains higher cutoff frequency compared to silicon based transistors. Alternatively, pHEMT enhance the performance of the HEMT in term of leakage, current conduction and the cutoff frequency of the device. The heterostructure of pHEMT improve the performance two-dimension electron gas (2DEG) in the channel layer. With these, pHEMT is believed could be perfectly used in the most of the high frequency application. In this project, small signal models of InGaAs/InAlAs/InP pHEMT with 7 extrinsic parameters and 8 intrinsic parameters are modelled.
  • Publication
    Non-linear analysis of Self-Switching Diodes as microwave rectifiers
    ( 2017-01-01)
    Shahrir Rizal Kasjoo
    ;
    Zulfadhli Zailan
    ;
    Sanna Taking
    ;
    Wan Zuki Azman Wan Muhamad
    ;
    Muammar Mohamad Isa
    ;
    Arshad M.
    A planar device known as the Self-Switching Diode (SSD) has been demonstrated as a high-speed rectifier, up to terahertz frequencies. The rectifying properties of SSD are dependent on a nonlinear current-voltage characteristic of the device. In this research, the rectification of two SSD rectifiers has been reported and their performances were evaluated. The observed results showed a good agreement with the nonlinear theoretical analysis of both rectifiers by means of a Taylor series which can be utilized in improving the rectifying performance of any diode-based rectifier specifically for diodes with tunable threshold voltage such as SSDs.
  • Publication
    Silicon Self-Switching Diode (SSD) as a Full-Wave Bridge Rectifier in 5G Networks Frequencies
    ( 2022-12-01)
    Yi Liang T.
    ;
    Nor Farhani Zakaria
    ;
    Shahrir Rizal Kasjoo
    ;
    Safizan Shaari
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Singh A.K.
    The rapid growth of wireless technology has improved the network’s technology from 4G to 5G, with sub-6 GHz being the centre of attention as the primary communication spectrum band. To effectively benefit this exclusive network, the improvement in the mm-wave detection of this range is crucial. In this work, a silicon self-switching device (SSD) based full-wave bridge rectifier was proposed as a candidate for a usable RF-DC converter in this frequency range. SSD has a similar operation to a conventional pn junction diode, but with advantages in fabrication simplicity where it does not require doping and junctions. The optimized structure of the SSD was cascaded and arranged to create a functional full-wave bridge rectifier with a quadratic relationship between the input voltage and outputs current. AC transient analysis and theoretical calculation performed on the full-wave rectifier shows an estimated cut-off frequency at ~12 GHz, with calculated responsivity and noise equivalent power of 1956.72 V/W and 2.3753 pW/Hz1/2, respectively. These results show the capability of silicon SSD to function as a full-wave bridge rectifier and is a potential candidate for RF-DC conversion in the targeted 5G frequency band and can be exploited for future energy harvesting application.
  • Publication
    Review of mixer design for low voltage - Low power applications
    ( 2017-09-26)
    Nurulain D.
    ;
    Musa F.A.S.
    ;
    Muammar Mohamad Isa
    ;
    Norhawati Ahmad
    ;
    Shahrir Rizal Kasjoo
    A mixer is used in almost all radio frequency (RF) or microwave systems for frequency translation. Nowadays, the increase market demand encouraged the industry to deliver circuit designs to create proficient and convenient equipment with very low power (LP) consumption and low voltage (LV) supply in both digital and analogue circuits. This paper focused on different Complementary Metal Oxide Semiconductor (CMOS) design topologies for LV and LP mixer design. Floating Gate Metal Oxide Semiconductor (FGMOS) is an alternative technology to replace CMOS due to their high ability for LV and LP applications. FGMOS only required a few transistors per gate and can have a shift in threshold voltage (VTH) to increase the LP and LV performances as compared to CMOS, which makes an attractive option to replace CMOS.
  • Publication
    Hybrid Statistical and Numerical Analysis in Structural Optimization of Silicon-Based RF Detector in 5G Network
    ( 2022-02-01)
    Yi Liang T.
    ;
    Nor Farhani Zakaria
    ;
    Shahrir Rizal Kasjoo
    ;
    Safizan Shaari
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Singh A.K.
    ;
    Sobri S.A.
    In this study, a hybrid statistical analysis (Taguchi method supported by analysis of variance (ANOVA) and regression analysis) and numerical analysis (utilizing a Silvaco device simulator) was implemented to optimize the structural parameters of silicon-on-insulator (SOI)-based self-switching diodes (SSDs) to achieve a high responsivity value as a radio frequency (RF) detector. Statistical calculation was applied to study the relationship between the control factors and the output performance of an RF detector in terms of the peak curvature coefficient value and its corresponding bias voltage. Subsequently, a series of numerical simulations were performed based on Taguchi’s experimental design. The optimization results indicated an optimized curvature coefficient and voltage peak of 26.4260 V−1 and 0.05 V, respectively. The alternating current transient analysis from 3 to 10 GHz showed the highest mean current at 5 GHz and a cut-off frequency of approximately 6.50 GHz, indicating a prominent ability to function as an RF detector at 5G related frequencies.