Experimental determination and simulation of the angular distribution of the metal flux during magnetron sputter deposition

To understand the film growth during magnetron sputter deposition a detailed knowledge of the flux of sputtered species from the target towards the substrate is vital. One important parameter is the angular distribution of the impinging neutral target atoms on the substrate, since it is responsible for, for example, self-shadowing effects. The determination of the angular distribution of the metal flux at an arbitrary point in the deposition chamber is achieved by a pinhole camera, where the information of the angular distribution is converted into a thickness profile. This paper describes the construction of such a pinhole camera which is capable of differential pumping, the determination of the angular distribution for a wide variety of target materials, and which can easily be inserted into a deposition chamber. The angular distributions of different materials (Cu, W, Al, Ti, Mg) at different parameters (pressure, lateral position and vertical position) are experimentally determined and compared with simulations obtained from a newly developed Monte Carlo code. It was also investigated whether parameters derived from the angular distribution are related to the degree of thermalization of the impinging particles