Uda Hashim
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Preferred name
Uda Hashim
Official Name
Uda, Hashim
Alternative Name
Hashimb, U.
Hashim, Uda
Hashim, U.
Uda, Hashim
Main Affiliation
Scopus Author ID
22633937800
Researcher ID
CVC-6955-2022

Research Output

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  • Publication
    Investigation of the absorption coefficient, refractive index, energy band gap, and film thickness for Al0.11Ga0.89N, Al0.03Ga0.97N, and GaN by optical transmission method
    ( 2009-07)
    Naser M. Ahmed
    ;
    Zaliman Sauli
    ;
    Uda Hashim
    ;
    Yarub Al-Douri
    The design of optoelectronic devices fabricated from III-Nitride materials is aided by knowledge of refractive index and absorption coefficient of these materials .The optical properties of Al0.11Ga0.89N, Al0.03Ga0.97N, and GaN grown by MOVPE on sapphire were investigated by means of transmittance measurements .The optical transmission method is successfully used to determine the refractive index (n), absorption coefficient (α), film thickness and energy gap of three samples of film over the spectral range of (1-5 eV)
  • Publication
    Fabrication of nano and micrometer structures using electron beam and optical mixed lithography process
    ( 2011-01)
    S. F. Abd Rahman
    ;
    Uda Hashim
    ;
    Mohammad Nuzaihan Md Nor
    ;
    M. E. A. Shohini
    In this paper, the fabricated pattern of nanometer and micrometer structures created with electron beam lithography (EBL) and optical lithography on silicon on insulator (SOI) material are presented. The resist used to demostrate this EBL pattern creation is ma-V 2403 which is a negative tone photoresist series, while positive resist PRI-2000A is used to transform photomask design using optical lithography. Three different patterns structures are fabricated on each sample namely alignment mark, silicon, nanowire and metal pad. The JEOL scanning electron microscopy (SEM) has been modified to integrate with RAITH software to be used for electron beam lithography. Nano-scaled nanowires were first patterned by EBL and formed by ICP ething followed by micro-sized-contact pads were defined bt photolithography process. The approachICP etching followed by micro-sized -pad were defined by photlithography process. The approach describe in this paper is a mix-and-match techniques uising both conventional photholilthography and advanced nanolithoragraphy, making use of an alignment strategy.
  • Publication
    Improvement in processing of micro and nano structure fabrication using O2 plasma
    ( 2011-01)
    Th. S. Dhahi
    ;
    Uda Hashim
    ;
    N. M. Ahmed
    Plasma has frequently been used by the industry as a last step surface preparation technique in an otherwise wet-etched process. Recent research of the chemistry of plasma led to a great understanding of plasma processes. It is by controlling the plasma conditions and gas mixture, ultra-fast plasma cleaning and etching is possible. With enhanced organic removal rates, plasma processed become more desirable as an environmentally sound alternative to traditional solvent or acid dominated process, not only as a cleaning tool, but also as a patterning and machining tool. In this paper, improvement in the processing of nanogap fabrication using Oâ‚‚ plasma is discussed including the parameters for PR patterning with two times limited in the Oâ‚‚ plasma process. For applications that have not been possible with limited usefulness, plasma processes are now approaching the realm of possibility. We introduce this work to fabricate and characterize the nanogap device fabrication Oâ‚‚ plasma technique for biosensor fabrication. In this review, two masks design are proposed. The first mask is for the lateral nanogap and the second mask is for a gold pad electrode pattern, and the lateral nanogap is introduced in the fabrication process using silicon, and gold as an electrode. Conventional photolithography technique is used to fabricate this nanogap (NG) based on the plasma etching technique. The increase in etching time when we apply the Oâ‚‚ plasma means an increase in the amount of etching, while in the case of reducing the time of etching means reducing the amount of etching, as shown in the results.
  • Publication
    Fabrication of nano and micrometer structures using electron beam and optical mixed lithography process
    ( 2011-01)
    S. F. Abd Rahman
    ;
    Uda Hashim
    ;
    Mohammad Nuzaihan Md Nor
    ;
    M. E. A. Shohini
    In this paper, the fabricated pattern of nanometer and micrometer structures created with electron beam lithography (EBL) and optical lithography on silicon on insulator (SOI) material are presented. The resist used to demostrate this EBL pattern creation is ma-V 2403 which is a negative tone photoresist series, while positive resist PRI-2000A is used to transform photomask design using optical lithography. Three different patterns structures are fabricated on each sample namely alignment mark, silicon, nanowire and metal pad. The JEOL scanning electron microscopy (SEM) has been modified to integrate with RAITH software to be used for electron beam lithography. Nano-scaled nanowires were first patterned by EBL and formed by ICP ething followed by micro-sized-contact pads were defined bt photolithography process. The approachICP etching followed by micro-sized -pad were defined by photlithography process. The approach describe in this paper is a mix-and-match techniques uising both conventional photholilthography and advanced nanolithoragraphy, making use of an alignment strategy.
  • Publication
    Design and fabrication of quantum dot single electron transistor structure using e-beam nanolithography
    ( 2011-07)
    Uda Hashim
    ;
    S. Madnasri
    ;
    Zul Azhar Zahid Jamal
    Quantum dot single electron transistor (QD SET) is fabricated using e-beam nanolithography (EBL) and is continued with the combination process of pattern dependent oxidation (PADOX) and high density plasma etching. EBL was used to pattern the whole masks of SET fabrication which consist of mask for doped area separator and the rest are for the formation of: source-quantum dot-drain, poly-Si gate, point contact and metal pad respectively. All of these masks were designed using offline GDSII Editor Software and later been exposed by EBL integrated using the scanning electron microscopy (SEM). In this paper, the whole designs of SET masks which are successively patterned are demonstrated and their nanostructures characterizations using SEM and atomic force microscopy (AFM) are reported. We found that the shape and dimension biases of schematic and SEM images of masks were caused by proximity effect. Therefore, while designing the SET masks, proximity effect, used resist and EBL equipment resolution were considered.
  • Publication
    Improvement in processing of micro and nano Structure fabrication using Oâ‚‚ plasma
    ( 2011-01)
    Th. S. Dhahi
    ;
    Uda Hashim
    ;
    N. M. Ahmed
    Plasma has frequently been used by the industry as a last step surface preparation technique in an otherwise wet-etched process. Recent research of the chemistry of plasma led to a great understanding of plasma processes. It is by controlling the plasma conditions and gas mixture, ultra-fast plasma cleaning and etching is possible. With enhanced organic removal rates, plasma processed become more desirable as an environmentally sound alternative to traditional solvent or acid dominated process, not only as a cleaning tool, but also as a patterning and machining tool. In this paper, improvement in the processing of nanogap fabrication using Oâ‚‚ plasma is discussed including the parameters for PR patterning with two times limited in the Oâ‚‚ plasma process. For applications that have not been possible with limited usefulness, plasma processes are now approaching the realm of possibility. We introduce this work to fabricate and characterize the nanogap device fabrication Oâ‚‚ plasma technique for biosensor fabrication. In this review, two masks design are proposed. The first mask is for the lateral nanogap and the second mask is for a gold pad electrode pattern, and the lateral nanogap is introduced in the fabrication process using silicon, and gold as an electrode. Conventional photolithography technique is used to fabricate this nanogap (NG) based on the plasma etching technique. The increase in etching time when we apply the Oâ‚‚ plasma means an increase in the amount of etching, while in the case of reducing the time of etching means reducing the amount of etching, as shown in the results.
  • Publication
    Thermal diffussion: a simulation based study on shallow junction formation
    ( 2012-07)
    Uda Hashim
    ;
    N. Hamat N. H,
    ;
    Siti Fatimah
    ;
    Tijjani Adam
    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
    SOI based nanowire single-electron transistors: design, simulation and process development
    ( 2008-01)
    Uda Hashim
    ;
    A. Rasmi
    ;
    Samsudi Sakrani
    One of the great problems in current large-scale integrated circuits is increasing power dissipation in a small silicon chip. Single-electron transistors which operate by means of oneby-one electron transfer, is relatively small and consume very low power and suitable for achieving higher levels of integration. In this research, the four masks step are involved namely source and drain mask, Polysilicon gate mask, contact mask, and metal mask. The masks were designed using ELPHY Quantum GDS II Editor with a nanowire length and nanowire width of approximately 0.10µm and 0.010 µm respectively. In addition, the process flow development of SET and the process and device simulation of SET are also explained in this paper. The Synopsys TCAD simulation tools are utilized for process and device simulation. The results from the device simulation showed that the final SET was operating at room temperature (300K) with a capacitance estimated around 0.4297 aF.
  • Publication
    Biotechnological processes in microbial amylase production
    ( 2017)
    Subash C. B. Gopinath
    ;
    Periasamy Anbu
    ;
    M. K. Md Arshad
    ;
    Thangavel Lakshmipriya
    ;
    Chun Hong Voon
    ;
    Uda Hashim
    ;
    Suresh V. Chinni
    Amylase is an important and indispensable enzyme that plays a pivotal role in the field of biotechnology. It is produced mainly from microbial sources and is used in many industries. Industrial sectors with top-down and bottom-up approaches are currently focusing on improving microbial amylase production levels by implementing bioengineering technologies. The further support of energy consumption studies, such as those on thermodynamics, pinch technology, and environment-friendly technologies, has hastened the large-scale production of the enzyme. Herein, the importance of microbial (bacteria and fungi) amylase is discussed along with its production methods from the laboratory to industrial scales.
  • Publication
    Preliminary studies on antimicrobial activity of extracts from aloe vera leaf, citrus hystrix leaf, zingiber officinale and Sabah snake grass against bacillus subtilis
    ( 2018)
    M.N.A. Uda
    ;
    Subash Chandra Bose Gopinath
    ;
    Nur Hulwani Ibrahim
    ;
    Mohd Khairul Rabani Hashim
    ;
    Nuradibah Mohd Amer
    ;
    Midhat Nabil Ahmad Salimi
    ;
    Tan Ewe Shen
    ;
    Ong Yee Fen
    ;
    Maisara A. M. Akhir
    ;
    Uda Hashim
    Herbal plants have several potential antimicrobial activities either as antifungal or antibacterial to fight against the disease and pathogen that attack the plants. The extractions of the Aloe vera leaf, Citrus hystrix leaf, Zingiber officinale rhizome and Sabah snake grass were selected in this study to fight against Bacillus subtilis. B. subtilis is a Gram-positive bacterium, rodshaped and catalase-positive that lives on decayed organic material. It is known as Gram-positive bacteria because of its thick peptidoglycan and would appear purple when subjected to Gram test. This species is commonly found in the upper layers of the soil, in meat or vegetables, in pastry, cooked meat, in bread or poultry products. The extracts of Sabah Snake Grass found to be most effective than A.vera leaf, Z. officinale, and C. hystrix against the B. subtilis.