| AVS 54th International Symposium | |
| Advanced Surface Engineering | Monday Sessions |
| Session SE+PS-MoA |
| Session: | Pulsed Plasmas in Surface Engineering |
| Presenter: | M. Lattemann, Linköping University, Sweden |
| Authors: | M. Lattemann, Linköping University, Sweden D. Jädernäs, Linköping University, Sweden U. Helmersson, Linköping University, Sweden |
| Correspondent: | Click to Email |
Transition metal (TM) nitrides are well known for their remarkable physical properties including high hardness and mechanical strength, chemical inertness, high temperature stability, low resistivity, and good optical properties. As a result they have become of high technological and scientific importance and are used in a wide range of applications. NaCl δ-TiN has received by far the most attention and is therefore often used as a model system. In this work, TiN thin films were deposited onto MgO(100) and MgO(111) substrates in an Ar/N2 atmosphere using high power impulse magnetron sputtering (HIPIMS). HIPIMS has earlier been proven to produce a highly ionized metal flux exhibiting a broad ion energy distribution with energies up to 100 eV advancing surface processes. It was shown that these ion energies are sufficient to produce fully dense films even at ambient temperature. However, the high amount of metal species with an energy around 1 eV promote the formation of underdense grain boundaries as the energy only allows the ions to interact with the nearest neighbor sites by single hop events. At ambient temperature and grounded substrate, the TiN thin films show a columnar structure with almost random orientation of the crystals as a result of combination of arriving species with high and low mobility as well as highly energetic ions creating defects and nucleation sites. The window for epitaxial growth of TiN for a variety of different process parameters was investigated. E.g. a more monoenergetic ion energy distribution can be achieved by tailoring the substrate bias and process conditions. In addition to the metal ion energy and substrate temperature, also the effect of assisting gas ion irradiation was investigated both during the pulse and in between the pulses, where no deposition occurred. In this way, the onset and breakdown of structure relation towards polycrystalline morphology can be monitored. The resulting structure of the TiN thin films was investigated by x-ray diffraction and high resolution transmission electron microscopy.