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The purpose of this paper is to elucidate the aging effect in dye-sensitized solar cells (DSSCs) sealed with thermoplastic film and to compare it with unsealed DSSCs.

The paper presents the steps of the fabrication of standard DSSC, as well as the DSSC-sealing processes, by using thermoplastic film. Current-voltage characterization was performed to observe the changes in efficiency, fill factor, short circuit current density and open circuit voltage for both unsealed and sealed DSSCs for aging time up to 336 h.

The unsealed DSSC showed significant drop in efficiency from 4.26 to 2.42 per cent within the first 5.5 h of aging time because of the leakage and volatilization of the solvent in the electrolyte. On the other hand, the sealed DSSC exhibited a gradual improvement of efficiency from 4.16 to 4.73 per cent after the first 216 h of aging time. The initial efficiency increment can be ascribed to the improved adsorption of electrolyte into the titanium dioxide film because of the gradual desorption of excess dye from TiO2 with increasing aging time.

This paper demonstrates the importance of the proper sealing process for the long-term operation of DSSC.

This paper aims to develop a low-cost hot-point which can facilitate the conductivity type of N-type and P-type zinc oxide (ZnO) films. In this study, a diode was made out of the N-type and P-type ZnO films, and current-voltage (I-V) characteristic measurements were conducted.

A low-cost hot-point probe consists of a soldering iron station, digital multimeter and a pair of probes. The setup is adopted to identify N-type and P-type ZnO films. In particular, P-type films have been deployed for the first time.

Hot-point probe setup has been successfully developed. Measurements of N-type films give a positive voltage reading, whereas P-type films give a negative voltage reading. The measured voltage dominates at 1 per cent for N-type Ga and at 15 per cent for P-type Na. I-V characteristics of the fabricated diode showed a similar trend to the conventional diode.

N-type has been often attempted. However, P-type has rarely been attempted because of the self-compensation effect in ZnO. There is a need to verify the conductivity type of ZnO films, especially P-type, as P-type films are not stable. The hot-point probe setup serves as a quick means to verify P-type ZnO films.

To the best of the authors’ understanding, this verification tool was developed and deployed to verify the N-type and P-type ZnO films. The P-type films are coated on top of the N-type films for diode I-V measurements.

The purpose of this paper is to address the influence of deposition process parameters. The substrate heating mechanisms are also discussed.

Deposition duration, sputtering power, working gas pressure, and substrate heater temperature on substrate heating in the direct current (DC) magnetron sputtering deposition process were investigated.

Results from the experiments show that, in DC magnetron sputtering deposition process, substrate heating is largely influenced by the process parameters and conditions.

This paper usefully demonstrates that substrate heating effects can be minimized by adjusting and selecting the proper sputtering process parameters; the production cost can be reduced by employing a higher sputtering power, lower working gas pressure and shorter deposition duration.

The purpose of this paper is to share valuable information about metallization in microelectronic industries by implementing tungsten silicide (WSi) thin film materials.

Direct current plasma magnetron sputtering technique was employed for the WSi film growth. Different sputtering parameters were investigated, and the WSi films were characterized using four‐point probe electrical measurement method.

The experimental results reveal that the sputtering parameters such as deposition pressure and substrate temperature exert significant influence on the electrical properties of the WSi films.

By tuning the sputtering parameters, the electrical properties of the WSi films can be optimized and the film resistivity can be reduced significantly.

The investigation results presented in this paper are useful information for microelectronic industries in the area of microelectronic devices metallization.

The fabrication method described in this paper allows fabricating low‐resistivity WSi films by employing a lower deposition pressure and a lower substrate temperature.

Die edge quality with its corresponding die strength are two important factors for excellent dicing quality especially for low-k wafers due to their weak mechanical properties and fragile structures. It is shown in past literatures that laser dicing or grooving does yield good dicing quality with the elimination of die mechanical properties. This is due to the excess heat energy that the die absorbs throughout the procedure. Within the internal structure, the mechanical properties of low-k wafers can be further enhanced by modification of the material. The purpose of this paper is to strengthen the mechanical properties of wafers through the heat-treatment process.

The methodology of this approach is by heat treating several low-k wafers that are scribed with different laser energy densities with different laser micromachining parameters, i.e. laser power, frequency, feed speed, defocus reading and single/multibeam setup. An Nd:YAG ultraviolet laser diode that is operating at 355 nm wavelength was used in this study. The die responses from each wafer are thoroughly visually inspected to identify any topside chipping and peeling. The laser grooving profile shape and deepest depth are analysed using a laser profiler, while the sidewalls are characterized by scanning electron microscopy (SEM) to detect cracks and voids. The mechanical strength of each wafer types then undergoes three-point bending test, and the performance data is analyzed using Weibull plot.

The result from the experiment shows that the standard wafers are most susceptible to physical defects as compared to the heat-treated wafers. There is improvement for heat-treated wafers in terms of die structural integrity and die strength performance, which revealed a 6% increase in single beam data group for wafers that is processed using high energy density laser output but remains the same for other laser grooving settings. Whereas for multibeam data group, all heat-treated wafer with different laser settings receives a slight increase at 4% in die strength.

Heat-treatment process can yield improved mechanical properties for laser grooved low-k wafers and thus provide better product reliability.

Zinc oxide (ZnO) is an emerging optoelectronic material due to its various functional behaviors. The purpose of this paper is to report on the fabrication and characterizations of ZnO microrods.

ZnO microrods were synthesized using sol‐gel immerse technique on oxidized silicon (Si) substrates. The oxidized Si substrates were immersed in ZnO aqueous solution for different times ranging from three to five hours. The surface morphologies of the ZnO microrods were examined using scanning electron microscope (SEM). In order to investigate the structural properties, the ZnO microrods were measured using an X‐ray diffractometer (XRD). The optical properties were measured using a photoluminescence (PL) spectrophotometer.

Characterization from SEM shows an enhanced growth of the ZnO rods with increasing immerse time. XRD characterizations demonstrate sharp and narrow diffraction peaks peculiar to ZnO, which implies that the rod is of high crystallinity. Based on the PL spectra, long immerse time results in the high peak in the UV region.

This paper concludes that the immerse time exerts an influence on the ZnO microrods. A longer immerse duration is preferred in the fabrication of the ZnO microrod, which is considered an emerging material for many advanced electronic and optoelectronic applications.

Power management of a wireless sensor node is important and needs to be designed efficiently without wasting excessive energy. The purpose of this paper is to report on the improvement of the power management of a wireless sensor node.

The design involves the implementation of solar recharging technology with single‐ended primary inductance converter (SEPIC) on a wireless sensor node in order to achieve the improvement in power management.

The combination of the solar recharging technology with SEPIC converter shows promising results for efficiently supplying the power to the wireless sensor node.

The design idea can be extended for many other electronic sensor applications, which can help to ensure an efficient power management of the sensor nodes.

The proposed design model demonstrates a new idea towards reduction of energy usage for wireless sensor nodes.