Formation of thin films of monocrystalline CoSi2 on (100) Si

Abstract The formation of monocrystalline (100) CoSi 2 layers is obtained by a thin-film reaction of sputtered Co with the top Si layer of Si/CoSi 2 /Si heterostructures, formed by ion implantation. The buried CoSi 2 layer serves as an excellent seed for imposing its crystal structure on the newly grown top CoSi 2 . A noncontinuous buried layer can also serve as a seed, hereby reducing the required implanted dose. The combination of ion implantation and regular silicide formation, therefore, becomes an attractive technique to form surface layers of monocrystalline (100) CoSi 2 on (100) Si. Patterned layers can be obtained by a masked ion implantation and a self-aligned Co-silicidation. In order to understand the relation between the amount of Co to be implanted versus the thickness and quality of the overgrown layer, a detailed study has been performed, for a wide range of implanted doses. Parameters of interest are the implantation energy to define the initial CoSi 2 precipitate distribution, the thickness of the sputtered Co layer and the anneal cycle for silicidation.