Universal Mobility-Field Curves For Electrons In Polysilicon Inversion Layer

This paper reports the studies on the inversion-layer mobility in n-channel Poly-Si TFT’s with 1016cm-3 substrate impurity concentration. The validity and limitations of the universal relationship between the inversion layer mobility and the effective normal field (Eeff) was examined

Design consideration of N-drift region doping concentration in high voltage VDMOS transistor

N-drift doping concentration has important contribution in determining the breakdown voltage and on-resistance of the device. It should be well considered because higher N- drift doping concentration can minimize the on-resistance of the device, but also lowering breakdown voltage of the device that expected to be high. It also has a proportional relationship with threshold voltage degradation caused by hot carrier injection. So the variation of N-drift doping concentration can be used to optimize the VDMOS transistor performance

Modelling of Swarm Communication

Swarm communication is a communication process of sending data within a certain area via agents.. Data will be sent to all the agents in this process. This is also closely related to the way of broadcasting via “short communication” as a way to find out the data among their agents. This field involved an in -depth study of the behaviour of the agents and by using a homogeneous approach, inspect the process of sending data. This includes investigation of independence of agents and the characteristics of sending and receiving data for a random process in a swarm. In this paper, techniques useful for swarm implemented bit-communication behaviour will be presented. There are two approaches that are used to send and receive signals. The reverse approach is where data can be resend to the sender for the next cycle, where the program randomly selects the nearest agents t o send data to. While for the nonreversing approach data is not able to return to the sender in the previous cycle. The non -reversing approach can improve system performance and efficiency. This paper presents the development of a swarm communication mode l and how it can be used to illustrate the communication process

Optical microbottle resonator with polyvinyl alcohol coating for sodium alginate concentration sensing

The research paper defined the effect of polyvinyl alcohol (PVA) coating on optical microbottle resonator (MBR) for sodium alginate concentration sensor. The resonator made from silica fiber SMF28 used a technique known as “soften-and compress”. The MBRs size is based on the three parameters, which is bottle diameter (Db), stem diameter (Ds) and bottle length (Lb). The MBR was then coated with PVA and named MBR-PVA-A, MBR-PVA-B and MBR-PVA-C. The coated MBR-PVA was then coupled with microfiber for characterisation and able to have Q-factor >105 for all conditions. The MBR-PVAs were then used for the sodium alginate sensor with liquid concentrations ranging from 1% to 6%. The MBR-PVAs performance is ultimately excellent, where the results are based on transmitted power and wavelength shift analysis. The MBR-PVAs are promising as sodium alginate concentration sensors by the sensitivity, linearity, stability, and repeatability performance

Compatibility Analysis of Silicon Nitride and Silicon Dioxide on HCI induced LDD MOSFET

Hot-carrier-injection (HCI) is one of important reliability issue under short-channel effect in modern MOSFET devices especially in nano-scaled CMOS technology circuits. The effect of the hot carrier can be reduced by introducing Lightly-Doped-Drain (LDD) structure on the device. The objective of this project is to study the effect of hot carrier in the LDD n-MOSFET. The LDD n-MOSFET is stressed with bias voltage at intervals of stressing time to determine the degradation model in the threshold voltage and drain current. From the parametrical analysis, it shows that the shift in threshold voltage and degradation in the drain current occurred after the MOSFET device is stressed with hot carrier stress test. The rate of threshold voltage shift and degradation of the drain current are dependence to the stressing time applied to the MOSFET device. The hot carrier stress test shows that the device with Si3N4 has smaller voltage shift compared to SiO2 material

ZnO Nanorods Coated Microfiber Loop Resonator For Relative Humidity Sensing

This paper reported a new humidity sensor, employing microfiber loop resonator (MLR) coated with Zinc Oxide (ZnO) as a probe. The MLR was constructed from a silica tapered fiber with a waist diameter of 7 µm, which was prepared using flame brushing technique. The self-touching loop was coated by ZnO using sol–gel method. A significant response to humidity changes from 35%RH to 85%RH was observed due to the changeable refractive index of the ZnO coating material which modified the light propagation at the output of the MLR. The result shows that the sensitivity of the proposed sensor increases by a factor of 2 as compared to the uncoated MLR. The output power of the ZnO coated MLR drops linearly from −29.3 dBm to −43 dBm when relative humidity increases from 35%RH to 85%RH. The linearity and resolution of the ZnO coated MLR also outperformed the uncoated MLR with 99.4% and 0.013%RH respectively

Formaldehyde sensing using tapered u-shape plastic optical fiber coated with zinc oxide nanorods

Continuous exposure to formaldehyde may cause injury to the central nervous, respiratory, blood, and immunological systems. Tapered U-shape plastic optical fiber (POF) coated with zinc oxide nanorods was evaluated at wavelength of 645 nm for formaldehyde vapor sensing within a concentration range from 5% to 20%. The tapered POF with 500 µm waist diameter was prepared using chemical etching technique. Zinc oxide nanorods were synthesized using hydrothermal method and growth for 12 hours on the tapered POF. The proposed sensor exhibited a good response to formaldehyde concentration ranging from 5% to 20% with sensitivity and linearity measured to be 0.00543V/% and 98.58%, respectively. Excellent measurement stability was observed when the concentrations from 5% and above are maintain over a 600 second period. Highest difference voltage was produced by 0.0958V due to the more scattering effect of ZnO nanorods at 20% of formaldehyde concentration. This proposed sensor might be also used to detect air pollution produced not just by formaldehyde vapor, but also by other dangerous or poisonous vapors or gases

ZnO nanorods coated tapered u-shape plastic optical fiber for relative humidity detection

A relative humidity sensor was fabricated by exploiting an evanescent wave (EW) on a U-bent tapered plastic optical fiber (POF) coated with zinc oxide (ZnO) nanorods. The POF was tapered manually using a polishing method to a diameter of 0.5 mm, a length of 5 cm, and a radius of 5 cm. ZnO nanorods were synthesized using a hydrothermal method and grown on the POF by a seeding process for 12 h. A significant response of the sensor was observed when the sensor was exposed to 35 to 90%RH due to the intense chemisorption process and changeable relative index in the POF. The sensitivity and resolution of the sensor have been improved by factors of 1.23 and 2.18, respectively, compared to the conventional tapered POF sensor without ZnO coating. Besides, the ZnO-coated sensor also exhibited better repeatability properties in terms of output voltage when exposed to 35 to 90%RH for three repeated measurements. The obtained results revealed that the proposed new POF sensor has an excellent sensing performance as an RH sensor in terms of sensitivity, repeatability, and stability propertie

Effect of HEC/PVDF coating on glass substrate for formaldehyde concentration sensing

This paper has reported demonstration of simple and low cost formaldehyde sensor utilizing Hydroxyethyl cellulose/Polyvinylidene fluoride (HEC/PVDF) coated glass substrate. It was integrated with Arduino microcontroller for data acquisition of the variation of the transmitted light during the sensing. The formaldehyde detection is based on the change in refractive index (RI) of the HEC/PVDF as a sensitive material which modulate the output light intensity when the concentration level of the formaldehyde increases. A significant response towards formaldehyde concentrations level was observed with the output voltage reduced linearly from 1.5V to 0.8V. The sensitivity of the proposed sensor improves by a factor of 1.09 as compared to uncoated glass substrate. It also performed better in term of stability, response time and hysteresis. The proposed sensor evades the used of costly optical sensor fabrication and manufacturing process which are more practical for large production while maintaining a good sensing performances. Based on the experiment results, the proposed approach has exhibited convincing potential as a formaldehyde sensor

Uric acid sensing using tapered silica optical fiber coated with zinc oxide nanorods

In this paper, fiber-optic sensors by different tapered lengths of silica optical fiber (SOF) coated with zinc oxide (ZnO) nanorods were fabricated and demonstrated to detect different concentrations of uric acid. The SOFs were tapered in the length of 1 cm, 3 cm, 5 cm, and 7 cm using flame brushing technique. ZnO nanorods were coated on the surface of the tapered SOFs for 24 hours using sol-gel immersion method. The sensing experiment was performed by dipping the SOF in the uric acid solution. One end of the SOF was connected to a light source and while the other end to an optical analyzer. The output of the sensor was analyzed for different uric acid concentration from 0 ppm to 500 ppm with the different tapered lengths of SOF sensors. The result shows that the sensor with tapered length of 7 cm had the highest sensitivity response of 0.0006 mV/ppm with linearity of 98.52%. In addition, all tapered size of sensor shows significant improvement of sensing performance with sensitivity consistently improved from 1 cm to 7 cm with good linearity as ZnO nanorods coated the tapered lengths. The detection limit was found to be at 0.2 ppm in the range of uric acid concentration