Synthesis and Characterization of Thin Films

Au in its bulk form is useful for many electronic applications because it is a good electrical and thermal conductor; however, at nanoscale, gold's properties change. For example as Au gets thinner its density decreases, it absorbs green light and appears red, and becomes less electrically conductive. Some of these characteristics make it a good candidate for developing optical biosensors. The purpose of this research is to synthesize and characterize nanoscale Au films at varying thicknesses, for future use in developing biosensors. The Au thin films were synthesized using a SPI-Module sputter coater and were characterized through atomic force microscopy, X-ray photoelectron spectroscopy, optical absorbance, and Hall effect measurement system. Our results showed that after annealing, the Au thin films presented a peak in absorbance. A shift in this peak when introduced to biological mediums could be utilized as a sensor.