Centre of Excellence for Advanced Sensor Technology (CEASTech) (Articles)http://dspace.unimap.edu.my:80/xmlui/handle/123456789/254412024-03-28T20:15:58Z2024-03-28T20:15:58ZEffect of substrate bias in copper sputtering plasma measured by Langmuir ProbeJia Wei, LowNafarizal, NayanMohd Zainizan, SahdanMahamad, Abd KadirMohd Khairul, AhmadAli Yeon, Md ShakaffAmmar, ZakariaFathinul Syahir, Ahmad SaadAhmad Faizal, Mohd Zainhttp://dspace.unimap.edu.my:80/xmlui/handle/123456789/391252015-03-05T08:00:18Z2014-04-01T00:00:00ZEffect of substrate bias in copper sputtering plasma measured by Langmuir Probe
Jia Wei, Low; Nafarizal, Nayan; Mohd Zainizan, Sahdan; Mahamad, Abd Kadir; Mohd Khairul, Ahmad; Ali Yeon, Md Shakaff; Ammar, Zakaria; Fathinul Syahir, Ahmad Saad; Ahmad Faizal, Mohd Zain
There are several techniques to deposit the metal oxide thin film such as electron beam evaporator, pulse laser deposition and reactive magnetron sputtering deposition. In this experiment, magnetron sputtering deposition techniques will be used to produce a copper oxide thin film due to its simplicity and repeatability performance. Recently, copper oxide thin film has been studied because of its low cost material, sensitivity to ambient condition and easiness to produce oxide thin film. It is one of the p-type semiconductor oxides materials that are suitable to be used as a gas sensing material. In order to increase the sensitivity and to optimize the properties of copper oxide thin film, it is essential to study on the plasma properties during the deposition of copper oxide. In current studies, Langmuir probe was used to investigate the effect of substrate bias towards the fabrication of copper oxide thin film at rf dissipation power of 400 W. The oxygen flow rate was fixed at 8sccm. The Langmuir probe tip was focus at roughly 2 cm above the substrate holder. The ion and electron current were collected from the plasma environment. Then the electron temperature, electron density, ion density, ion flux, Debye length and plasma potential at various substrate biases were evaluated from the current-voltage curve. The electron temperature at various oxygen flow rates was almost unchanged. The effect of substrate bias toward the electron temperature was also almost unseen, except that the electron temperature at-40 V bias voltage was slightly lower than others. In addition, the ion flux at the same plasma condition shows that the ion flux was higher at-40 V substrate bias voltage. The results suggest that the ion bombardment effect toward the deposited copper oxide thin film would be higher at low oxygen flow rate. Thus it will create a rough surface morphology or nanostructured copper oxide thin film. This is a potential ways to improve the sensitivity of copper oxide gas sensor.
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2014-04-01T00:00:00ZInfluence of dissipation power in copper sputtering plasma measured by optical emission spectroscopyKevin, LowNafarizal, Nayan, Prof. Madya Dr.Mohd Zainizan, Sahdan, Dr.Abd Kadir, Mahamad, Dr.Mohd Khairul, Ahmad, Dr.Ali Yeon, Md Shakaff, Prof. Dr.Ammar, ZakariaFathinul Syahir, Ahmad Sa'adAhmad Faizal, Mohd Zainhttp://dspace.unimap.edu.my:80/xmlui/handle/123456789/335322014-04-08T07:36:31Z2014-01-01T00:00:00ZInfluence of dissipation power in copper sputtering plasma measured by optical emission spectroscopy
Kevin, Low; Nafarizal, Nayan, Prof. Madya Dr.; Mohd Zainizan, Sahdan, Dr.; Abd Kadir, Mahamad, Dr.; Mohd Khairul, Ahmad, Dr.; Ali Yeon, Md Shakaff, Prof. Dr.; Ammar, Zakaria; Fathinul Syahir, Ahmad Sa'ad; Ahmad Faizal, Mohd Zain
Copper oxide is a low cost material, easy process fabrication and sensitivity to ambient conditions. Therefore, it is a suitable p-type semiconductor oxides material to be used as a gas sensing material. In order to raise the sensitivity of the copper oxide gas sensor, study on the correspondence in between the coated thin film with coating parameters is an important part. In current study, optical emission spectroscopy is used to investigate the reactive magnetron sputtering plasma during the deposition of copper oxide thin film. The measurement point was focused at roughly 2cm above the substrate holder. The emission of copper, oxygen and argon in the reactive magnetron sputtering were observed at various plasma conditions. In general, the emission of copper, oxygen and argon increased when the discharge rf power is increased. On the other hand, oxygen line intensity was found to be excess when the oxygen flow rate is above 8sccm. The result suggests the best condition to deposit the copper oxide thin film using solid 3 copper target.
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2014-01-01T00:00:00ZHighly selective molecular imprinted polymer (MIP) based sensor array using interdigitated electrode (IDE) platform for detection of mango ripenessHuzein Fahmi, HawariNurul Maisyarah, SamsudinAli Yeon, Md Shakaff, Prof. Dr.Yufridin, Wahab, Dr.Uda, Hashim, Prof. Dr.Ammar, ZakariaSupri, Abdul Ghani, Prof. Madya Dr.Mohd Noor, Ahmad, Prof. Dr.http://dspace.unimap.edu.my:80/xmlui/handle/123456789/331772014-03-27T14:03:51Z2013-01-01T00:00:00ZHighly selective molecular imprinted polymer (MIP) based sensor array using interdigitated electrode (IDE) platform for detection of mango ripeness
Huzein Fahmi, Hawari; Nurul Maisyarah, Samsudin; Ali Yeon, Md Shakaff, Prof. Dr.; Yufridin, Wahab, Dr.; Uda, Hashim, Prof. Dr.; Ammar, Zakaria; Supri, Abdul Ghani, Prof. Madya Dr.; Mohd Noor, Ahmad, Prof. Dr.
Detection of mango ripeness was performed by developing a highly selective molecularly imprinted polymers (MIP) layer combined with interdigitated electrode (IDE) as sensor. Mango volatiles from different week of ripeness stage were studied and volatiles such as α-pinene, 7-terpinene and terpinolene were selected as markers to indicate different stages of fruit maturity. Through computational modelling, an optimum composition ratio of cross linker, functional monomer and target molecule for IDE-MIP sensor has been successfully determined. Utilizing this optimum ratio, the MIPs templates were then synthesized and deposited onto an array of IDE platform. When the sensor array was exposed to mango volatiles, the IDE-MIP sensor will then exhibit a shift in capacitance compared to a non target IDE-MIP sensor. In an array, the difference capacitance shift of each IDE-MIP sensor would create a specific profile of ripeness identification. The use of polyethylene terephthalate (PET) as a substrate would allow a "low cost and flexible" sensor implementations. This study provides a potential non destructive solution to discriminate the mango ripeness stage hence improving the quality of harvest.
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2013-01-01T00:00:00ZDevelopment of interdigitated electrode molecular imprinted polymer sensor for monitoring alpha pinene emissions from mango fruitHuzein Fahmi, HawariNurul Maisyarah, SamsudinAli Yeon, Md Shakaff, Prof. Dr.Supri, Abdul Ghani, Prof. Madya Dr.Mohd Noor, Ahmad, Prof. Dr.Yufridin, Wahab, Dr.Uda, Hashim, Prof. Dr.http://dspace.unimap.edu.my:80/xmlui/handle/123456789/331762014-03-27T13:46:08Z2013-01-01T00:00:00ZDevelopment of interdigitated electrode molecular imprinted polymer sensor for monitoring alpha pinene emissions from mango fruit
Huzein Fahmi, Hawari; Nurul Maisyarah, Samsudin; Ali Yeon, Md Shakaff, Prof. Dr.; Supri, Abdul Ghani, Prof. Madya Dr.; Mohd Noor, Ahmad, Prof. Dr.; Yufridin, Wahab, Dr.; Uda, Hashim, Prof. Dr.
Alpha Pinene is a type of terpene hydrocarbons commonly emitted in substantial amounts by plants such as mango. Using Interdigitated Electrode (IDE) structure, a sensor for detecting Alpha Pinene volatile by using molecular imprinted polymer (MIP) was fabricated. The MIP membrane contained methacrylic acid, which formed specific cavities originated by target molecule. The use of Polyethylene Terephthalate (PET) as a substrate would allow a "low cost and flexible" sensor implementations. The IDE MIP sensor is capable to detect Alpha Pinene contained gas. The sensor characteristics were strongly influenced by the composition ratio of cross-linker, functional monomer and template molecule. The remained molecule on MIP can be removed by immersing thus the sensor can be used repeatedly. By determining Alpha Pinene volatile released during pre-matured until matured period, one could use this as a data point as potential non destructive solution to discriminate the mango ripeness stage hence improving the quality of harvest
Link to publisher's homepage at http://www.elsevier.com/
2013-01-01T00:00:00Z