Characterizing copper nanoparticle DC sputtering with oxygen interference

The properties of a material are directly dictated by its size, shape and internal structure. In a time where research on nanoscale is widely practiced and the demand for the smallest possible electronics grows, new challenges emerge in the creating and usage of nanomaterials. In this thesis the workings of a new Nanosys550 Deposition System from MANTIS Deposition LTD for creation of nanoparticles is described with in the present work a specific focus on copper clusters. First the basics of direct current (DC) magnetron sputtering are explained. This form of sputtering works by accelerating argon plasma against a copper target, thereby breaking of single copper atoms which form a gas. By cooling this gas into supersaturation, copper nanoclusters are formed by condensation processes. Although, these processes are controlled by only a few system settings, together they comprise a complex system. These settings and their effects are discussed and have been investigated by experimentation. The latter has been done in a first experiment series by Half Factorial Design (HFD) with Center Point Experiments (CPE) to characterize the standard operation window of the new system. A second experiment series on Energetic Cluster Impact (ECI) has been performed to examine the charge character of the sputtered copper clusters by attempting cluster acceleration with an applied bias voltage to the substrate holder. The copper clusters were deposited on TEM grids and silicon wafer pieces for both experiment series. The results of the HFD experiments were imaged with the use of a Transmission Electron Microscope (TEM) and analyzed by statistical software, which calculated the effects of the separate system variables. Assessment of these effects revealed that they behaved according to a-priori (qualitative) expectations but were non-significant. This led to the discovery of oxygen leakage into the vacuum system and several attempts to prevent this problem. At the end, the oxygen problems have been solved and the observed HFD results are explained by literature research. Simultaneous with the preventive measures the ECI experiments were performed. The results were imaged also by TEM and an Atomic Force Microscope (AFM). The obtained data from both imaging techniques revealed no support or proof for ECI, although the absence of cluster charge seems unlikely from literature research.