Relatively little information is available on the growth patterns of gold aluminide compound in accurate 3D measurement as compared with 2D images of the projected surface. A 3D surface imaging technique by using infinite focus microscope (IFM) was proposed in this study to observe and explain the effects of bonding parameters on growth pattern of gold aluminide compound formed between a 25.48 μm 4N gold wire and an aluminum pad metallization. Two bonding factors, which were varied, were ball bonding force and ultrasonic current while bonding time and temperature were kept constant. The 3D surface measurement provides topographical and color information of the bonded region, which indicates that optimum bonding condition has a significant effect on uniform growth and wide coverage area of gold aluminide compound. Results illustrated by this technique were used as additional information to the results produce by the conventional methods such as cross section optical image and scanning electron microscope (SEM) micrographs, to gain a better understanding on the physical behavior of gold aluminide compound.

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Dye sensitized solar cell (DSSC) is a new class of low-cost solar cell, that belongs to third generation solar cells in thin film based. It is based on a semiconductor formed between a photo-sensitized anode and an electrolyte, known as photoelectrochemical system. A lot of research has been conducted due to their interesting potential for low-cost, lightweight, disposable and having cell efficiency up to 10%. This paper reports the fabrication of dye sensitized solar cells using TiO2 nanoparticles and chlorophyll as active layer. TiO2 nanoparticles were prepared by sol-gel method while the chlorophyll was extracted from Pandanus amaryllifolius (Pandan leaf). TiO2 film was prepared on ITO coated glass using dip coating technique and then immersed overnight in the chlorophyll solution. An electrolyte solution composed of PC-LiClO4 was injected into the cell before sealed using glass that was coated with Pt as top electrode. An active area of 4.48 cm2 was fabricated by black masking the front side. The performance of the device was studied by observing the current-voltage characteristics of the device in dark at ambient temperature and under illumination of 100 mW/cm2 light. It was found that the device showed rectifier property in the dark and able to generate electrical current under light.

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