TiN deposition and morphology control by scalable plasma-assisted surface treatments

Abstract

A method to modify the mechanical properties and morphology of thin TiN films by controlling the ion fluxes via purposefully shaped magnetic field is developed to enhance the effectiveness of plasma-enhanced deposition of TiN on a large (up to 400 mm in diameter) substrate. For this purpose, the two main schemes of the plasma control are examined. When the substrate is a part of the plasma-generating circuit, TiN is deposited in the magnetron-like arc configuration of the magnetic field. This configuration is used to control ion fluxes for cleaning, etching, and heating of the substrate, and eventually, to control the mechanical properties and morphology of the deposits. When exposing the substrate to the plasma of an external plasma source, the magnetic traps of the bottle configuration with mirrors near the plasma source and substrate surface are created. It is shown that the ion fluxes from the external plasma source can be controlled by the location and powering of the control magnetic coils, which direct nitrogen and Ti ions to the surface. The proposed method is generic and could be used for controlling various nitride materials including but not limited to BN, NbN, W2N and TaN.