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Article
Publication date: 20 January 2012

T.S. Dhahi, U. Hashim, M.E. Ali and Nazwa Taib

Nanogap electrodes have important applications in power saving devices, electrochemical sensors and dielectric detections of biomolecules. The purpose of this paper is to report…

Abstract

Purpose

Nanogap electrodes have important applications in power saving devices, electrochemical sensors and dielectric detections of biomolecules. The purpose of this paper is to report on the fabrication and characterization of polysilicon nanogap patterning using novelties technique.

Design/methodology/approach

Polysilicon material is used to fabricate the nanogap structure and gold is used for the electrode and two chrome masks are used to complete this work; the first mask for the nanogap pattern and a second mask for the electrode. The method is based on the control of the coefficients (temperature and time) with an improved pattern size resolution thermal oxidation.

Findings

Physical characterization by scanning electron microscopy (SEM) demonstrates such nanogap electrodes could be produced with high reproducibility and precision. Electrical characterization shows that nanogap enhanced the sensitivity of the device by increase the capacitance and the conductivity as well. They have also good efficiency of power consumption with high insulation properties.

Originality/value

With this technique, there are no principal limitations to fabricating nanostructures with different layouts down to several different nanometer dimensions. The paper documents the fabrication of nanogaps electrodes on a polysilicon, using low‐cost techniques such as vacuum deposition and conventional lithography. Polysilicon is a low‐cost materials and has desirable properties for semiconductor applications. A method of preparing a nanogap electrode according to the present innovation has an advantage of providing active surface that can easily be modified for immobilizations of biomolecules.

Details

Microelectronics International, vol. 29 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 26 April 2013

T.S. Dhahi, U. Hashim and M.E. Ali

The purpose of this paper was to systematically study the electrical properties of 5‐, 42‐ and 75‐nm gap polysilicon structures to evaluate the potentiality of these structures to…

Abstract

Purpose

The purpose of this paper was to systematically study the electrical properties of 5‐, 42‐ and 75‐nm gap polysilicon structures to evaluate the potentiality of these structures to be used in biomolecular sensing devices.

Design/methodology/approach

The authors previously reported the fabrication and morphological characterization of these structures. In this report, they electrically probed the presence of nanogap through current measurement. The effects of electrolytes on the capacitance profiles of these structures were systematically studied with air, water and various dilutions of phosphate buffer saline.

Findings

An increment in capacitance was found with the increment in electrolyte concentration. Improvement in current flow, capacitance, permittivity, and conductivity were observed with the smaller size nanogaps, suggesting their applications in low power consuming devices.

Originality/value

Since nanogap‐based dielectric biosensing devices need to be operated with a low level of current to avoid biomolecular damage, these structures should have potential applications in dielectric‐based biomolecular detection using a low cost dielectric analyser.

Details

Microelectronics International, vol. 30 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 20 June 2016

Yijun Teh, Asral Bahari Jambek and Uda Hashim

This paper aims to discuss a nanoscale biosensor and its signal analysis algorithms.

1113

Abstract

Purpose

This paper aims to discuss a nanoscale biosensor and its signal analysis algorithms.

Design/methodology/approach

In this work, five nanoscale biosensors are reviewed, namely, silicon nanowire field-effect-transistor biosensors, polysilicon nanogap capacitive biosensors, nanotube amperometric biosensors, gold nanoparticle-based electrochemical biosensors and quantum dot-based electrochemical biosensors.

Findings

Each biosensor produces a different output signal depending on its electrical characteristics. Five signal analysers are studied, with most of the existing signal analyser analyses based on the amplitude of the signal. Based on the analysis, auto-threshold peak detection is proposed for further work.

Originality/value

Suitability of the signal processing algorithm to be applied to nano-biosensors was reported.

Details

Sensor Review, vol. 36 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 2 October 2017

Roungdao Klinjapo, Kamonchanok Areerat and Pornpong Sutthirak

The purpose of this paper is to investigate the potential of fruit waste materials from fruit industry as sources of powerful natural antioxidants.

Abstract

Purpose

The purpose of this paper is to investigate the potential of fruit waste materials from fruit industry as sources of powerful natural antioxidants.

Design/methodology/approach

The peels of mango, rambutan, and santol were extracted and analyzed for their antioxidant activity. Pork ball samples were prepared and treated with different natural extracts at various concentrations, namely 0.05, 0.10, 0.15, and 0.20% (v/w), compared with the control (no natural extract), and then stored at 4°C. The samples were investigated at the zeroth, third, fifth, eighth and tenth day to find out the antioxidant activity of the total phenolic content and lipid oxidation including the evaluation of the change of rancid flavor and color during storage. All statistical results were analyzed by RCBD using SPSS at p⩽0.05.

Findings

During storage, the amount of phenolic compound in a pork ball by adding fruit extracts at various concentrations slightly decreased, while the lipid oxidation slightly increased. Mango extract showed the best efficiency to delay lipid oxidation in the pork ball for ten days followed by santol extract and rambutan extract. For sensory evaluation, the pork ball with fruit extract at various concentrations showed the lower rancidity development than control, and mango extract at 0.20% (v/w) showed the best delaying rancidity during ten-day storage. Thus, mango peel extract at 0.20% (v/w) showed the highest effectiveness of antioxidant activity against lipid oxidation in pork ball.

Originality/value

This study was continued from the previous research which investigated the best extraction condition for by-products of mango, rambutan, and santol. From that study, the authors found that the crude extracts need further research on their antioxidant property in foods. The research findings have provided information regarding the interesting new natural antioxidant that can be applied into lipid-containing foods to delay the rancidity and extend the shelf life.

Details

British Food Journal, vol. 119 no. 10
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 2 August 2011

Uda Hashim, Nazwa Taib, Thikra S. Dhahi and Azizullah Saifullah

Nanobiosensors based on nanogap capacitor are widely used for measuring dielectric properties of DNA, protein and biomolecule. The purpose of this paper is to report on the…

Abstract

Purpose

Nanobiosensors based on nanogap capacitor are widely used for measuring dielectric properties of DNA, protein and biomolecule. The purpose of this paper is to report on the fabrication and characterization polysilicon nanogap patterning using novelties technique.

Design/methodology/approach

Overall, the polysilicon nanogap pattern was fabricated based on conventional lithographic techniques. For size expansion technique, by employing simple dry thermal oxidation, the couple of nanogap pattern has been expanded to lowest nanogap value. The progress of nanogap pattern expansion was verified by using scanning electron microscopy (SEM). Conductivity, resistivity, and capacitance test were performed to characterize and to measure electrical behavior of full device fabrication.

Findings

SEM characterization emphasis on the expansion of polysilicon nanogap pattern increasing with respect to oxidation time. Electrical characterization shows that nanogap enhanced the sensitivity of the device at the value of nano ampere of current.

Originality/value

These simple least‐cost method does not require complicated nanolithography method of fabrication but still possible to serve as biomolecular junction. This approach can be applied extensively to different design of nanogap structure down to several nanometer levels of dimensions. A method of preparing a nanogap electrode according to the present innovation has an advantage of providing active surface that can be easily modified for immobilizations of biomolecules.

Details

Microelectronics International, vol. 28 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 23 January 2024

Anas A. Al Bakri and Nazzal M. Kisswani

This study aims to provides the insights on the advantages and disadvantages of international franchising and licensing from the perspectives of legal and business considerations…

Abstract

Purpose

This study aims to provides the insights on the advantages and disadvantages of international franchising and licensing from the perspectives of legal and business considerations in the Gulf Cooperation Council (GCC).

Design/methodology/approach

Using a quantitative research approach, the authors conducted a survey with 150 business owners and franchisees in the GCC and analyzed the data using descriptive statistics, structural equation modeling and frequency analysis.

Findings

The findings reveal that while international franchising and licensing offer significant benefits for business expansion and revenue growth, they also pose risks related to legal compliance, cultural differences and intellectual property protection. Indeed, the results of this study provide valuable insights into the advantages and disadvantages of international franchising and licensing in the GCC from both legal and business perspectives.

Originality/value

There is limited research on the legal and business perspectives of international franchising and licensing in the GCC. This study contributes to the literature by providing a comprehensive analysis of the legal and business perspectives of international franchising and licensing in the GCC.

Details

International Journal of Law and Management, vol. 66 no. 3
Type: Research Article
ISSN: 1754-243X

Keywords

Article
Publication date: 29 April 2014

Tijjani Adam and U. Hashim

The purpose of this study is to present reports on fabrication of silicon (Si) nanowires (NWs). The study consists of microwire formation on silicon-on-insulator (SOI) that was…

Abstract

Purpose

The purpose of this study is to present reports on fabrication of silicon (Si) nanowires (NWs). The study consists of microwire formation on silicon-on-insulator (SOI) that was fabricated using a top-down approach which involved conventional photolithography coupled with shallow anisotropic etching.

Design/methodology/approach

A 5-inch p-type silicon-on-insulator (SOI) coated with 250nm layer and Photoresist (PR) with thickness of 400nm is coated in order to make pattern transfer via binary mask, after the exposure and development, a resist pattern between 3 μm-5 μm were obtained, Oxygen plasma spreen was used to reduce the size of the PR to 800 μm, after this, the wafer with 800 μm was loaded into SAMCO inductively coupled plasma (ICP)-RIE and got silicoon microwire was obtained. Next, the sample was put into an oxidation furnace for 15, 30, 45 and 60 minutes and the sample was removed and dipped into a buffered oxide etch solution for five minutes to remove all the SiO2 ashes.

Findings

The morphological characterization was conducted using scanning electron microscopy and atomic force microscopy. At terminal two, gold electrodes which were designated as source and drain were fabricated on top of individual NWs using conventional lithography electrical and chemical response. Once the trimming process has been completed, the device's current–voltage (I-V) characteristic was measured by using a Keithley 4200 semiconductor parameter analyser. Devices with different width of wires approximately 20, 40, 60 and 80 nm were characterized. The wire current variation as a function of the pH variation in voltage was investigated: pH monitoring for variations of pH values between 5 and 9.

Originality/value

This paper provides useful information on novel and yet simple cost-effective fabrication of SiNW; as such, it should be of interest to a broad readership, especially those interested in micro/nanofabrication.

Details

Microelectronics International, vol. 31 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 11 January 2024

Dingyu Shi, Xiaofei Zhang, Libo Liu, Preben Hansen and Xuguang Li

Online health question-and-answer (Q&A) forums have developed a new business model whereby listeners (peer patients) can pay to read health information derived from consultations…

Abstract

Purpose

Online health question-and-answer (Q&A) forums have developed a new business model whereby listeners (peer patients) can pay to read health information derived from consultations between askers (focal patients) and answerers (physicians). However, research exploring the mechanism behind peer patients' purchase decisions and the specific nature of the information driving these decisions has remained limited. This study aims to develop a theoretical model for understanding how peer patients make such decisions based on limited information, i.e. the first question displayed in each focal patient-physician interaction record, considering argument quality (interrogative form and information details) and source credibility (patient experience of focal patients), including the contingent role of urgency.

Design/methodology/approach

The model was tested by text mining 1,960 consultation records from a popular Chinese online health Q&A forum on the Yilu App. These records involved interactions between focal patients and physicians and were purchased by 447,718 peer patients seeking health-related information until this research.

Findings

Patient experience embedded in focal patients' questions plays a significant role in inducing peer patients to purchase previous consultation records featuring exchanges between focal patients and physicians; in particular, increasingly detailed information is associated with a reduced probability of making a purchase. When focal patients demonstrate a high level of urgency, the effect of information details is weakened, while the interrogative form is strengthened.

Originality/value

The originality of this study lies in its exploration of the monetization mechanism forming the trilateral relationship between askers (focal patients), answerers (physicians) and listeners (peer patients) in the business model “paying to view others' answers” in the online health Q&A forum and the moderating role of urgency in explaining the mechanism of how first questions influence peer patients' purchasing behavior.

Details

Aslib Journal of Information Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2050-3806

Keywords

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