Conformity of aluminum thin films deposited onto micro-patterned silicon wafers by pulsed laser deposition, magnetron sputtering, and CVD

Complex materials, exhibiting a cocktail of properties, are currently needed for many applications. In this context, new requirements arise in terms of materials processing, such as the synthesis of sub-micrometer objects, or the coating and functionalization of complex surfaces of powders, porous materials, or micro-patterned devices. Depending on the requirements, the aim may be to duplicate the original design of the surface, or to modify it (filling of holes etc.). Physical vapor deposition (PVD) and CVD are promising techniques for the deposition of thin films on such substrates. In order to compare the ability of various deposition techniques to coat complex surfaces, a micro-patterned silicon wafer has been developed. In the present work, aluminum thin films are deposited on this model substrate by two PVD techniques; pulsed laser deposition (PLD) and magnetron sputtering (MS), and by metal-organic (MO)CVD. Scanning electron microscopy (SEM) is performed in order to determine the microstructure and study the thickness conformit