Low Homologous Temperature (0.2) Sputtering of Indium Films on Silicon (POSTPRINT)

Abstract : Substrate temperature is used to control the film morphology and packing of indium metal deposited by DC sputtering. Indium is sputtered on silicon at room- and liquid nitrogen cryogenic-temperatures resulting in very different homologous temperatures of 0.7 and 0.17. The deposition of the indium film at 0.2 homologous temperature results in increased film packing density, reduced voids, and a near specular indium surface which is very different from the extremely rough room temperature sample. The samples are characterized using atomic force microscope, scanning electron microscopy, transmission electron microscopy, and selective area electron diffraction. This technique for achieving low surface roughness indium has many potential uses for microelectronic packaging.