LOW-TEMPERATURE DEPOSITION OF TITANIUM NITRIDE

A new technique for depositing hard, dense, well-adhering TiN with exc ellent adhesion is described. Taking advantage of the high degree of i onization of the material emitted from a cathodic are source, a short, very high voltage pulse (the order of 5-20 kV for 1-3 mu s at a frequ ency of some 1-2 kHz) is applied to the substrate in addition to the u sual d.c. bias during reactive deposition. The high bias accelerates t he ions located within the sheath during the short pulse and their mom entum modifies the properties of the coatings as indicated above. The technology, termed Hyper-Ion, is readily retrofitted to existing physi cal vapor deposition systems equipped with cathodic are sources. The p resent work presents results on titanium nitride deposited onto temper ature-sensitive materials including low alloy steel, and aluminum 6061 -T6 at a substrate temperature of 150 degrees C. The coating has a typ e-T microstructure and the substrates do not lose mechanical strength.