Processing Temperature Dependence on Surface Morphology and Microstructure of Gold Films

Abstract

AbstractMicrostructure properties, and surface morphology of gold films processed at different temperature were investigated by transmission electron microscopy (TEM) and atomic force microscope (AFM). The film thickness was chosen less than several hundreds angstrong. Previous electrical measurement found that the low temperature (LT=77K) film showed several orders lower resistance compared to the film obtained at room temperature with very thin (about 100Å) thickness. This indicated potential application of these LT films on electronic and optoelectronic devices. TEM study found that the LT films showed much smaller density of grain boundaries than that of the room temperature (RT=300K) samples. In AFM observation, for film thickness of 100Å, LT film showed smoother, and continuous surface while the RT film consisted of discrete islands. When the thickness was increased to 200Å, the LT film showed much larger-sized grains compare to that of the RT film. For LT deposition, 2-dimensional larger-sized grains were first formed at low temperature deposition which later extended to be 3-dimension. The low grain boundary density of the LT film is consistent with its lower resistivity observation.