The effect of plasma density on the deposition and ion implantation to thematerials with three-dimensional topologies in metal d.c. plasma-based ionimplantation

Titanium and nitrogen ions were implanted into the silicon substrates, whic h were adhered to the materials of three-dimensional shapes such as trench and sphere, and the titanium nitride films were deposited on the substrate by plasma-based ion implantation using a titanium vacuum are in nitrogen ga s. The applied pulse voltage formed nearly uniform implanted layer of the t itanium and nitrogen ions all over the surfaces of the materials of three-d imensional shape. The distribution of the electron density in the plasma sp ace was measured with a Langmuir probe. The deposition rate of titanium nit ride film was closely connected with the electron density, which is equal t o the density of titanium and nitrogen ions. The electron density decreased with increasing distance from the are-source cathode due to a divergent fl ow of titanium ions. The variation in thickness of the implanted layer with position was small compared to that of the deposited layer. For the trench with the width of 16 mm, the maximum ratio of the thickness of the implant ed layer was 2.5, whereas that of the thickness of the deposited layer was 10. (C) 2000 Elsevier Science B.V. All rights reserved.