Zarimawaty Zailan
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Zarimawaty Zailan
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Zarimawaty, Zailan
Alternative Name
Zailan, Z.
Zailan, Zarimawaty
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Scopus Author ID
55603553500
Researcher ID
EHB-9502-2022

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  • Publication
    Improved rectification performance and terahertz detection in hybrid structure of self-switching device (SSD) and planar barrier diode (PBD) using two-dimensional device simulation
    ( 2020-01-01)
    Nor Farhani Zakaria
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Zarimawaty Zailan
    ;
    Mohd Khairuddin Md Arshad
    ;
    Song A.
    Recently, simulations of In0.48Ga0.52As-based Planar Barrier Diode (PBD) and Self- Switching Device (SSD) as millimeter-wave rectifiers were reported. Both PBD and SSD have a planar structure, but with different insulating shapes and working principles. In this work, a hybrid structure of the reported PBD and SSD in a parallel configuration is proposed, to exploit the advantages of each device. The advantages of high rectifying properties in the SSD and fast switching rate of the PBD are combined in this hybrid structure in order to obtain an improved rectification performance at zero-bias in the near terahertz frequency region. Analysis of the curvature co-efficient, γ, which is defined as the ratio of the second order to the first order derivative of the device’s I-V function was performed to evaluate the rectification performance. AC transient analyses were then executed in various frequencies to imitate the high-frequency signal inputs. By using this hybrid structure, the highest value of γ achieved has been improved to ~19 V-1 at 70 mV, and ~6 V-1 at zero- bias (compared to the previous results on PBDs). The estimated cut-off frequency obtained was ~360 GHz (0.36 THz), operating at zero-bias.
      5  38
  • Publication
    Self-switching diodes as RF rectifiers: Evaluation methods and current progress
    ( 2019-06-01)
    Zakaria N.
    ;
    Shahrir Rizal Kasjoo
    ;
    Isa M.
    ;
    Zarimawaty Zailan
    ;
    Arshad M.
    ;
    Sanna Taking
    In the advancement of the Internet of Things (IoT) applications, widespread uses and applications of devices require higher frequency connectivity to be explored and exploited. Furthermore, the size, weight, power and cost demands for the IoT ecosystems also creates a new paradigm for the hardware where improved power efficiency and efficient wireless transmission needed to be investigated and made feasible. As such, functional microwave detectors to detect and rectify the signals transmitted in higher frequency regions are crucial. This paper reviewed the practicability of self switching diodes as Radio Frequency (RF) rectifiers. The existing methods used in the evaluation of the rectification performance and cut-off frequency are reviewed, and current achievements are then concluded. The works reviewed in this paper highlights the functionality of SSD as a RF rectifier with design simplicity, which may offer cheaper alternatives in current high frequency rectifying devices for application in low-power devices.
      31  3
  • Publication
    Fabrication and simulation of silicon nanogaps pH sensor as preliminary study for Retinol Binding Protein 4 (RBP4) detection
    (Universiti Malaysia Perlis (UniMAP), 2025-01)
    M. I. Hashim
    ;
    Mohammad Nuzaihan Md Nor
    ;
    Mohamad Faris Mohamad Fathil
    ;
    M. Shaifullah A.S
    ;
    C. Y. Chean
    ;
    Nur Hamidah Abdul Halim
    ;
    Zarimawaty Zailan
    ;
    Mohd Khairuddin Md Arshad
    ;
    Muzamir Isa
    ;
    Ayu Wazira Azhari
    ;
    M. Syamsul
    ;
    Rozaimah A.T.
    In this research, a silicon nanogap biosensor has the potential to play a significant role in the field of biosensors for detecting Retinol Binding Protein 4 (RBP4) molecules due to its unique nanostructure morphology, biocompatibility features, and electrical capabilities. Additionally, as preliminary research for RBP4, a silicon nanogap biosensor with unique molecular gate control for pH measurement was developed. Firstly, using conventional lithography followed by the Reactive-ion etching (RIE) technique, a nanofabrication approach was utilized to produce silicon nanogaps from silicon-on-insulator (SOI) wafers. The critical aspects contributing to the process and size reduction procedures were highlighted to achieve nanometer-scale size. The resulting silicon nanogaps, ranging from 100 nm to 200 nm, were fabricated precisely on the device. Secondly, pH level detection was performed using several types of standard aqueous pH buffer solutions (pH 6, pH 7, pH 12) to test the electrical response of the device. The sensitivity of the silicon nanogap pH sensor was 7.66 pS/pH (R² = 0.97), indicating that the device has a wide range of pH detecting capacity. This also includes the silicon nanogap biosensor validated by simulation, with the sensitivity obtained being 3.24 μA/e.cm² (R² = 0.98). The simulation of the sensitivity is based on the interface charge (Qf) that represents the concentration of RBP4. The results reveal that the silicon nanogap biosensor has excellent characteristics for detecting pH levels and RBP4 with outstanding sensitivity performance. In conclusion, this silicon nanogap biosensor can be used as a new electrical RBP4 biosensor for biomedical diagnostic applications in the future.
      3  21
  • Publication
    Simulation of unipolar planar device with asymmetrical barrier profile: a planar barrier diode
    (AIP Publishing, 2017-09-26)
    Zarimawaty Zailan
    ;
    Shahrir Rizal Kasjoo
    ;
    Nor Farhani Zakaria
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Sanna Taking
    By introducing a funnel-shape semiconductor channel to create an asymmetrical energy barrier profile, a type of nonlinear device has been proposed and simulated which is referred as planar barrier diode (pbd). An applied voltage v across a pbd provides different height of the barrier depending on the sign of v. This results in a nonlinear current-voltage characteristic that resembles a typical diode behavior and therefore it can be used in signal rectification. The intrinsic cut-off frequency obtained in the simulation of the p-type silicon pbd rectifier was ∼15 ghz.
      5  19
  • Publication
    Design and characterization of self-switching diode and planar barrier diode as high-frequency rectifiers
    ( 2018)
    Zarimawaty Zailan
    The development of high-speed rectifying devices has become one of major research areas which can be utilized in many applications, including radio-frequency (RF) and detection systems. Examples of these devices are Schottky diode and planar-doped barrier diode. However, all these excellent devices require a very challenging in fabrication process due to their complex structures and a precise doping concentration for each critical layers which are relatively high cost. The prospects of using electronic devices with planar structure are therefore become increasingly promising. These planar devices provide additional advantages of being not only simple but also able to operate at high frequencies. As such, in this research work, the feasibility of utilizing two silicon-based planar nanodevices of self-switching diode (SSD) and planar barrier diode (PBD) for microwave and terahertz rectification has been demonstrated using simulations. SSD has recently been demonstrated as room-temperature rectifiers operating at terahertz frequencies. In this research work, the rectifying performance of SSD is evaluated using a parameter known as the curvature coefficient, derived from the current-voltage (I-V) characteristic of the device. The effects of varying the geometrical structure and the insulator dielectric relative permittivity (from 1 – 9.3) of SSD on the curvature coefficient of the device are studied and analyzed by means of a two-dimensional device simulator. The simulations are also performed under temperature range of 250 – 500 K. The results show that the highest cut-off frequency attained in this research work is approximately 19 GHz, operating at unbiased condition. By implementing similar simulation settings used in demonstrating siliconbased SSDs, a new unipolar planar nanodiode as a rectifier is introduced and developed in this research work. This new device is referred as PBD which has a funnel-shaped geometrical channel that allows current to flow across the device. At zero bias, the nonuniform depletion region, developed at the neck of the funnel-shape channel due to surface charges at semiconductor/insulator interface, is predicted to create an energy barrier along the channel with asymmetrical profile. An external voltage applied across a PBD is expected to produce different height of the energy barrier depending either the voltage given is positive or negative. As a result, a nonlinear I-V characteristic is realized which can be utilized in signal rectification. This operating principle of PBD has been demonstrated and validated in the simulations of this research work. It has also been described using thermionic emission theory which may govern the flow of current across the device. Similar to SSD, the rectification performance of PBD is characterized and evaluated based on the curvature coefficient and cut-off frequency of the device. By varying the geometrical design and insulator dielectric relative permittivity (from 1-9.3) of PBD, curvature coefficient of the device can be optimized in order to improve the rectification performance. The highest cut-off frequency obtained in the simulation of this work is approximately 0.8 THz. Both SSD and PBD have a planar architecture that can therefore be realized in a single lithography step which makes the whole fabrication process of the devices simpler, faster and at lower cost when compared with other conventional electronic devices.
      1  67
  • Publication
    Rectification performance of self-switching diodes in silicon substrate using device simulator
    (Institute of Electrical and Electronics Engineers (IEEE), 2017-01-03)
    Zarimawaty Zailan
    ;
    Shahrir Rizal Kasjoo
    ;
    Nor Farhani Zakaria
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Sanna Taking
    A planar nanodevice, known as the self-switching diode (SSD) has been demonstrated to rectify electromagnetic signals at microwave and terahertz frequencies. This diode has a non-linear current-voltage (I-V) characteristic due to the structure of the device which consists of asymmetric nanochannel. To further explore the properties of SSD rectifiers, in this work, silicon-based SSDs with different dielectric materials that filled up the trenches of the devices were simulated using ATLAS device simulator under the temperature range of 250 K-500 K. The results showed that the rectification performance of the SSDs was deteriorated with increasing temperature for all dielectric materials which might be due to the thermal-activated electronic transport behavior of the devices.
      8  16
  • Publication
    Fabrication and simulation of silicon nanowire pH sensor for Diabetes Mellitus detection
    ( 2023-04)
    C. Y. Chean
    ;
    Mohammad Nuzaihan Md Nor
    ;
    Mohamad Faris Mohamad Fathil
    ;
    M. I. Hashim
    ;
    Nur Hamidah Abdul Halim
    ;
    Zarimawaty Zailan
    ;
    Mohd Khairuddin Md Arshad
    ;
    Syamsul Syahrun Awang@Hashim
    ;
    Rozaimah A.T
    Diabetes Mellitus (DM) is a disease failed to control the balance of blood sugar level due to lack of insulin thereby it effect human health. In Malaysia, there are around 3.9 millions people aged 18 years old and above have diabetes according to National Health and Morbidity Survey 2019. Silicon Nanowire is a nanostructure which has ultra-high sensitivity and non-radioactive that has potential given good performances when applied on pH sensor and biosensor. Silicon nanowire pH sensor and biosensor is an electronic sensor that investigated to improve the sensitivity and accuracy for detecting DM. This project consists of two parts, which are fabrication of silicon nanowire pH sensor and simulation of silicon nanowire biosensor as preliminary study. In fabrication, silicon nanowire of pH sensor is fabricated by conventional lithography process, reaction ion etching (RIE) and metallization to achieved the width of 100 nm silicon nanowire. The pH6, pH7, pH10 and DI water as analytes to analysis the current-voltage (I-V) characteristics of silicon nanowire pH sensor. In second part, the silicon nanowire biosensor as preliminary study is done simulation by Silvaco ATLAS devices simulator. The silicon nanowire with 30 nm in height and 20 nm in width of biosensor is designed and simulated to analyze the performance in terms of sensitivity. I-V characteristics of silicon nanowire biosensor according to different concentration of negative interface charge is determined. The negative interface charge represent as the Retinol Binding Protein 4 (RBP4) which is used to diagnose DM. The I-V characteristic based on the change in current, resistance and conductance to determine sensitivity. Lastly, the sensitivity of silicon nanowire pH sensor obtained 23.9 pS/pH while the sensitivity of simulated silicon nanowire biosensor obtained 3.91 nS/e.cm2. The results shown the more negative charge of concentration analyte attached on surface silicon nanowire has been accumulated more current flow from drain terminal to source terminal. It leads to the resistance becomes highest and obtained good sensitivity. In summary, the silicon nanowire pH sensor exhibited good performance and high sensitivity in detection pH level. The simulated silicon nanowire biosensor is capable of detecting biomolecular interactions charges to obtained high sensitive and accuracy result.
      3  25
  • Publication
    Effect of channel length to the frequency response of Si-based Self-Switching Diodes using two-dimensional simulation
    ( 2020-12-18)
    Zarimawaty Zailan
    ;
    Shahrir Rizal Kasjoo
    ;
    Nurul Bariah Idris
    ;
    Khairul Affendi Rosli
    ;
    Nor Farhani Zakaria
    ;
    Muammar Mohamad Isa
    A planar nanodevice, known as the self-switching diode (SSD) which can be exploited as a high-speed rectifier in a wide range of applications. The non-linearity in the I-V characteristic of the SSD structure has been aimed for rectification application at GHz frequencies is reported. In this work simulation has been conducted on Si-based SSD structure with 230 nm L-shaped channels using ATLAS device simulator under the channel length range of 0.5 μm to 1.3 μm. Furthermore, the validity of the cut-off frequency has also been described using a theoretical value of f t at zero bias. The results showed that the optimization in the channel length of the SSD can assist the high cut-off frequency of SSD rectifying behavior to efficiently operate as microwave rectifier.
      5  42
  • Publication
    Rectification performance of self-switching diode in various geometries using ATLAS simulator
    (IEEE, 2017-01-03)
    Nor Farhani Zakaria
    ;
    Shahrir Rizal Kasjoo
    ;
    Zarimawaty Zailan
    ;
    Muammar Mohamad Isa
    ;
    Mohd Khairuddin Md Arshad
    ;
    Sanna Taking
    Characterization on a planar nano-device, known as self-switching diode (SSD) aimed for rectification application at high frequencies is reported. Simulation has been conducted on InGaAs-based SSD with 70 nm L-shaped channels using twodimensional (2D) ATLAS simulator. The current-voltage (I-V) characteristic of the device is found asymmetrical, similar to I-V behavior of a diode. The structure geometries of the channel are varied in term of channel length, channel width, and trenches width to observe the I-V behavior of the device. Furthermore, the curvature co-efficient of the SSD has been evaluated by extrapolating the simulated I-V graphs and the rectification performance of each configuration has been observed and concluded. The results obtained can assist the optimization in the design of the SSD to efficiently operate as microwave rectifier, especially in radio frequency harvesting application.
      5  20
  • Publication
    An overview of self-switching diode rectifiers using green materials
    (AIP Publishing, 2017-09-26)
    Shahrir Rizal Kasjoo
    ;
    Zarimawaty Zailan
    ;
    Nor Farhani Zakaria
    ;
    Muammar Mohamad Isa
    ;
    Syahrun Nizam Md Arshad @ Hashim
    ;
    Sanna Taking
    A unipolar two-terminal nanodevice, known as the self-switching diode (SSD), has recently been demonstrated as a room-temperature rectifier at microwave and terahertz frequencies due to its nonlinear current-voltage characteristic. The planar architecture of SSD not only makes the fabrication process of the device faster, simpler and at a lower cost when compared with other rectifying diodes, but also allows the use of various materials to realize and fabricate SSDs. This includes the utilization of 'green' materials such as organic and graphene thin films for environmental sustainability. This paper reviews the properties of current 'green' SSD rectifiers with respect to their operating frequencies and rectifying performances, including responsivity and noise-equivalent power of the devices, along with the applications.
      4  18