화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.26, No.1, 103-113, 2008
Numerical investigation via three-dimensional Monte Carlo modeling of sputtering and deposition processes in a direct current unbalanced magnetron discharge
A linked set of Monte Carlo applications has been developed in order to investigate the sputtering, deposition, and ionization processes in a circular direct current unbalanced magnetron discharge. Particles respond to prescribed electric and magnetic fields, the former taken from experimental measurements, and self-consistent plasma behavior resulting in changes in the fields is not accounted for. The motion of energetic electrons emitted from the target surface by ion impacts is followed in the gas phase in order to characterize ionization and excitation collisions and elastic scattering with argon filling gas. The inhomogeneous erosion, track profile is computed and compared with experimental measurements. The transport of titanium sputtered neutrals between the target and substrate surfaces is then analyzed using both a rigid sphere collision model and an interatomic potential model to describe collisions between sputtered neutrals and background gas atoms. The radial emission distribution of sputtered atoms is taken from the electron transport model. The mean arrival energy and the angular distribution of titanium neutrals impinging on the substrate surface, and the metal density profile between target and substrate are calculated. Finally, the electron impact ionization of titanium neutrals in a plasma formed by a mixture of titanium (10% of argon density) and argon atoms is simulated, motivated by the promising possibility of controlling the deposition process by influencing the direction of the ion flux. (C) 2008 American Vacuum Society.