Development of an ion beam sputtering system for Si/Ge multi-layer deposition

A V-shaped Si target which consists of two Si planes is designed for an Ion beam sputter deposition (IBSD) system where Ar+ is generated in a Kaufman type ion source. The deposition rate of Si increases from 7.63 A/min to 10.23 A/min with the V-shaped target. Using this system, two types of structures with 5 and 20 Si and Ge layers are formed. High energy (1.0 MeV) Ge+ are irradiated on these films to doses of 1.0x1016 ions/cm2 and 2.0x1016 ions/cm2 at a substrate temperature of 350degC. Rutherford Backscattering Spectroscopy (RBS) reveals that a 20-layered Si and Ge film changes into a graded SiGe mixture film by the ion mixing, but the crystallization does not occur. (author)